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Sample records for floods case northeastern

  1. Land-use, climate and floods dynamics in Northeastern Italy (Veneto)

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    Sofia, Giulia; Roder, Giulia; Tarolli, Paolo

    2016-04-01

    The Veneto Region in North-eastern Italy is today one of the most extensive inhabited and economically competitive urban landscapes in Europe, where infrastructure transformations have been recently accompanied by a number of serious hydraulic dysfunctions. Major concerns arise for frequent rainfall events which can couple with land-use changes with consequences on flooding (Sofia et al. 2014). The aim of this work is to propose a preliminary long-term, region-scale analysis of land-use, rainfall regime and flood dynamics in the region. To investigate the changes in floods, we considered the events registered in Veneto starting from the ~1900 to the year 2000 (Guzzetti and Tonelli, 2004). For this time frame, we analyzed trends in the number of flooded locations, flood events, as well as trends in the number of flooding days. We then investigated the accumulated percentages of flooded sites contributed by the accumulated percentage of flooding days in each year. The idea is to investigate, for the given period, the presence of drastic changes in the curve steepness (knickpoints), implying that less days of flood contribute to a notable increase in the percentage of the flooded locations. For the land-use dynamics we considered the urban area extent for three timeframes in the last century (60s, 90s, 2000s). From these, we created area cartograms in which the sizes of each drainage catchment in Veneto was deformed in proportion to the urban areas in each municipality, as well as in proportion to changes in soil sealing, and we related these maps to the number of flooded locations. For the climatic characterization, we considered a measure of the aggressivity and irregularity of the rainfall regime, to quantify the incidence of intense rainfall events on the yearly amount of precipitation. In spite of the limitations due to the different awareness of the impact of floods on the territory during the years, the floods analysis shows some recent knickpoints, indicating

  2. Improving Coastal Flood Risk Assessments for the Northeastern United States: New York City to Boston

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    Woodruff, J. D.; Stromer, Z.; Talke, S. A.; Orton, P. M.

    2015-12-01

    Interest in extreme flood vulnerability in the Northeastern U.S. has increased significantly since Hurricane Sandy caused more than $50 billion dollars in damages. Despite increased focus there is still no overall consensus regarding the true return period in the region for flood events of Sandy's magnitude. The application of Generalized Extreme Value (GEV) theory to water level data is one of the most common techniques for estimating the return period for these rare events. Here we assess the skill of this popular technique by combining modeled, instrumental and sedimentologically derived records of flooding for the region. We show that GEV derived return periods greatly and consistently underappreciate risk for sites from New York City east to southern Cape Cod. This is in part because at these locations maximum annual flood data represents a mixture of two very different populations of storms, i.e. tropically derived disturbances and extratropical Nor'easters. Nor'easters comprise a majority of floods with 10-yr return periods and shorter, hurricanes for 100-yr floods or longer, and a combination in between. In contrast, the GEV technique functions better in estimating the 100-yr flood for points north of Cape Cod including Boston. At these locations flooding occurs more often from just one type of disturbance, i.e. Nor'easters. However, modeled and sedimentary reconstructions of storms indicate hurricanes likely still dominate flood distribution at northern location like Boston for 500 yr or greater events. Results stress the need for separating storm populations before applying the GEV technique, especially where flood behavior can vary depending on the type of disturbance.

  3. Flood hazard and flood risk assessment at the local spatial scale: a case study

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    Matej Vojtek

    2016-11-01

    Full Text Available With regard to minimizing flood damage, there are measures of different character each of which has its justification and plays an important role in flood protection. Implementation of traditional flood protection measures is still very important; however, an increasing role should be played particularly by flood prevention and flood risk management. The paper presents a case study on flood hazard and flood risk assessment at the local spatial scale using geographic information systems, remote sensing, and hydraulic modelling. As for determining flood hazard in the model area, which has 3.23 km2, the estimation of maximum flood discharges and hydraulic modelling were important steps. The results of one-dimensional hydraulic modelling, which are water depth and flow velocity rasters, were the basis for determining flood hazard and flood risk. In order to define flood risk, the following steps were applied: determining flood intensity on the basis of water depth and flow velocity rasters, determining flood hazard using three categories (low, medium, and high based on flood intensity, defining vulnerability for the classes of functional areas using three categories of acceptable risk (low, medium, and high, and lastly determination of flood risk which represents a synthesis of flood hazard and vulnerability of the model area.

  4. Geomorphic response to an extreme flood in two Mediterranean rivers (northeastern Sardinia, Italy): Analysis of controlling factors

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    Righini, Margherita; Surian, Nicola; Wohl, Ellen; Marchi, Lorenzo; Comiti, Francesco; Amponsah, William; Borga, Marco

    2017-08-01

    A high-magnitude, low-frequency flash flood affected two ungauged rivers (northeastern Sardinia, Italy) on 18 November 2013. This study investigates the response of channel reaches in a Mediterranean environment featuring different morphological settings (i.e., alluvial, semialluvial, and bedrock boundaries) with the aims of (i) detecting the morphological effects of this large flood and (ii) analyzing a range of morphological and hydraulic variables as potential controlling factors of channel response. Channel widening was the dominant geomorphic response observed, and it occurred at different magnitudes among the study subreaches. Within individual subreaches, channel width increased from 1.1 to 6.2 times the pre-flood width. A significant trend in channel widening is observed, especially in alluvial subreaches where the narrowest channels were prone to enlarge more compared to the widest channels. Considerable erosion of valley sides also occurred in confined and partly confined semialluvial and bedrock subreaches. A range of parameters influenced the geomorphic role of the flood, and a series of selected morphological and hydraulic controlling factors showed robust correlations with changes in channel width, although correlations were stronger in alluvial subreaches. Analysis and documentation of channel response and its variability through different morphological settings is crucial to provide a basis from which to forecast future river sensitivity to geomorphic adjustment to high-magnitude floods and improve flood management strategies.

  5. The use of a flood index to characterise flooding in the north-eastern region of Bangladesh

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    Bhattacharya B.

    2016-01-01

    Full Text Available Flooding in the Haor region in the north-east of Bangladesh is presented in this paper. A haor is a saucershaped depression, which is used during the dry period (Dec to mid-May for agriculture and as a fishery during the wet period (Jun-Nov. Pre-monsoon flooding till mid-May causes agricultural loss. The area is bordering India, and is fed by some flashy Indian catchments. The area is drained mainly by the Surma-Kushiyara river system. The terrain generally is flat and the flashy characteristics die out within a short distance from the border. Limited studies on the region, particularly with the help of numerical models, have been carried out in the past. Therefore, an objective of the current research was to set up numerical models capable of reasonably emulating the physical system. Such models could, for example, associate different gauges to the spatio-temporal variation of hydrodynamic variables and help in carrying out a systemic study on the flood propagation. A 1D2D model, with one-dimensional model for the rivers (based on MIKE 11 from DHI and a two-dimensional model for the haors (based on MIKE 21 from DHI were developed. In order to characterize flooding in the large area a flood index is proposed, which is computed based on the hydrograph characteristics such as the rising curve gradient, flood magnitude ratio and time to peak. The index was used in characterising flooding in the Haor region. In general, two groups of rivers were identified. The study enabled identifying the hot-spots in the study area with risks from flooding.

  6. Case studies of extended model-based flood forecasting: prediction of dike strength and flood impacts

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    Stuparu, Dana; Bachmann, Daniel; Bogaard, Tom; Twigt, Daniel; Verkade, Jan; de Bruijn, Karin; de Leeuw, Annemargreet

    2017-04-01

    Flood forecasts, warning and emergency response are important components in flood risk management. Most flood forecasting systems use models to translate weather predictions to forecasted discharges or water levels. However, this information is often not sufficient for real time decisions. A sound understanding of the reliability of embankments and flood dynamics is needed to react timely and reduce the negative effects of the flood. Where are the weak points in the dike system? When, how much and where the water will flow? When and where is the greatest impact expected? Model-based flood impact forecasting tries to answer these questions by adding new dimensions to the existing forecasting systems by providing forecasted information about: (a) the dike strength during the event (reliability), (b) the flood extent in case of an overflow or a dike failure (flood spread) and (c) the assets at risk (impacts). This work presents three study-cases in which such a set-up is applied. Special features are highlighted. Forecasting of dike strength. The first study-case focusses on the forecast of dike strength in the Netherlands for the river Rhine branches Waal, Nederrijn and IJssel. A so-called reliability transformation is used to translate the predicted water levels at selected dike sections into failure probabilities during a flood event. The reliability of a dike section is defined by fragility curves - a summary of the dike strength conditional to the water level. The reliability information enhances the emergency management and inspections of embankments. Ensemble forecasting. The second study-case shows the setup of a flood impact forecasting system in Dumfries, Scotland. The existing forecasting system is extended with a 2D flood spreading model in combination with the Delft-FIAT impact model. Ensemble forecasts are used to make use of the uncertainty in the precipitation forecasts, which is useful to quantify the certainty of a forecasted flood event. From global

  7. Flood Seasonality in a Changing Climate - A Comparison Between Northern Europe and Northeastern North America

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    Matti, B.; Dahlke, H. E.; Dieppois, B.; Lawler, D.; Lyon, S. W.

    2016-12-01

    Fluvial flood events have a large impact on humans, both socially and economically. Concurrent with climate change flood seasonality in cold environments is expected to shift from a snowmelt-dominated to a rainfall-dominated flow regime. This would have profound impacts on water management strategies, i.e. flood risk mitigation, drinking water supply and hydro power. In addition, cold climate hydrological systems exhibit complex interactions with catchment properties and large-scale climate fluctuations making the manifestation of changes difficult to detect and predict. Understanding a possible change in flood seasonality is essential to mitigate risk and to keep management strategies viable under a changing climate. This study explored changes in flood seasonality across near-natural catchments in cold environments of the North Atlantic region (40 - 70° N) using circular statistics and trend tests. Results indicate strong seasonality in flooding for snowmelt-dominated catchments with a single peak occurring in spring (March through May), whereas flood peaks are more equally distributed throughout the year for catchments located close to the Atlantic coast and in the south of the study area. Flood seasonality has changed over the past century seen as decreasing trends in summer maximum daily flows and increasing winter and spring maximum daily flows. Mean daily flows corroborate those findings with approximately 50% of the catchments showing significant changes. Comparing Scandinavia to North America the same trends could be detected with a stronger signal at the west coast of Scandinavia due to the Westerlies. Contrasting trends were detected for spring flows, for which North American catchments showed decreasing trends whereas increasing trends were observed across Scandinavia. Such changes in flood seasonality have clear implications for management strategies such as the estimation of design floods for flood prevention measures.

  8. Periodic 18.6-year and cyclic 11-year induced drought and flood in northeastern China and some global implications

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    Currie, Robert Guinn; Fairbridge, Rhodes W.

    The general patterns of climatic evolution in China during the Holocene are reviewed, and following the postglacial eustatic rise of sea-level and the institution of the East Asian Monsoon, the systems and principal fluctuations are found to be concordant with those operating elsewhere in the globe. China's unique wealth of written history provides an abundance of proxy data on the climatic record and that record now furnishes a basis for analysing both long-term and short-term fluctuations, as well as sunspot behavior, that together provide an insight into extraterrestrial forcing. Recent Chinese work suggests a solar forcing, but our own studies suggest rather that a lunar tidal component, reinforced at times by the solar element may prove more important. Analysis of a drought-flood index for Peking (Beijing) in northeastern China since A.D. 1470 supports evidence (Hameed et al., 1983) for both periodic lunar nodal 18.6-year and solar cyclic 11-year induced drought-flood in the region. The nodal term exhibits bistable phasing with respect to epochs of tidal maxima (for our century epochs occurred at 1917.5, 1936.1, 1954.7 and 1973.3), a phenomenon previously found in drought-flood proxy data for South America (Currie, 1983), India (Currie, 1984a), North America (Currie, 1984d), and Africa (Hameed and Currie, 1985; Currie and Hameed, 1985). Solar cycle epochs of drought-flood are tabulated for the past two centuries, and compared with those from North America and Africa.

  9. Floods, Habitat Hydraulics and Upstream Migration of Neritina virginea (Gastropoda: Neritidae) in Northeastern Puerto Rico.

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    JUAN F. BLANCO; FREDERICK N. SCATENA

    2005-01-01

    Massive upstream migrations of neritid snails (Neritidae: Gastropoda) occur in tropical and subtropical streams worldwide, but their seasonality and proximate causes are unknown. We monitored massive upstream migrations of Neritina virginea for 99 weeks, and conducted a detailed study of snail density, size, and hydraulic descriptors in lower Río Mameyes, northeastern...

  10. Assessing fluvial flood risk in urban environments: a case study

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    Longo Elisa

    2016-01-01

    Full Text Available Nowadays, floods are among the most impactful calamities regarding costs. Looking at the natural hazards damage data collected in the International Disaster Database (EM-DAT, it is observable a significant increase over the past four decades of both frequency of floods and associated costs. Similarly, dramatic trends are also found by analyzing other types of flood losses, such as the number of people affected by floods, homeless, injured or killed.To deal with the aforementioned rise of flood risk, more and more efforts are being made to promote integrated flood risk management, for example, the Flood Directive 2007/60/EC. The main goals of this research are the estimation of flood damages using the KULTURisk methodology and the comparing of the projected costs with the observed one. The case study is the 2002 flood in Eilenburg. According to KULTURisk methodology, two major classes of data are considered to evaluate flood risk damage: hydraulic data as regards Hazard and economic information to assess Exposure and Vulnerability This study shows the possibility to extend the lesson learned with the Eilenburg case study in other similar contexts.

  11. Flood Response System—A Case Study

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    Yogesh Kumar Singh

    2017-06-01

    Full Text Available Flood Response System (FRS is a network-enabled solution developed using open-source software. The system has query based flood damage assessment modules with outputs in the form of spatial maps and statistical databases. FRS effectively facilitates the management of post-disaster activities caused due to flood, like displaying spatial maps of area affected, inundated roads, etc., and maintains a steady flow of information at all levels with different access rights depending upon the criticality of the information. It is designed to facilitate users in managing information related to flooding during critical flood seasons and analyzing the extent of damage. The inputs to FRS are provided using two components: (1 a semi-automated application developed indigenously, to delineate inundated areas for Near-Real Time Flood Monitoring using Active Microwave Remote Sensing data and (2 a two-dimensional (2D hydrodynamic river model generated outputs for water depth and velocity in flooded areas for an embankment breach scenario. The 2D Hydrodynamic model, CCHE2D (Center for Computational Hydroscience and Engineering Two-Dimensional model, was used to simulate an area of 600 km2 in the flood-prone zone of the Brahmaputra basin. The resultant inundated area from the model was found to be 85% accurate when validated with post-flood optical satellite data.

  12. Small river plumes off the northeastern coast of the Black Sea under average climatic and flooding discharge conditions

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    Osadchiev, Alexander; Korshenko, Evgeniya

    2017-06-01

    This study focuses on the impact of discharges of small rivers on the delivery and fate of fluvial water and suspended matter at the northeastern part of the Black Sea under different local precipitation conditions. Several dozens of mountainous rivers flow into the sea at the study region, and most of them, except for several of the largest, have little annual runoff and affect adjacent coastal waters to a limited extent under average climatic conditions. However, the discharges of these small rivers are characterized by a quick response to precipitation events and can significantly increase during and shortly after heavy rains, which are frequent in the considered area. The delivery and fate of fluvial water and terrigenous sediments at the study region, under average climatic and rain-induced flooding conditions, were explored and compared using in situ data, satellite imagery, and numerical modeling. It was shown that the point-source spread of continental discharge dominated by several large rivers under average climatic conditions can change to the line-source discharge from numerous small rivers situated along the coast in response to heavy rains. The intense line-source runoff of water and suspended sediments forms a geostrophic alongshore current of turbid and freshened water, which induces the intense transport of suspended and dissolved constituents discharged with river waters in a northwestern direction. This process significantly influences water quality and causes active sediment load at large segments of the narrow shelf at the northeastern part of the Black Sea compared to average climatic discharge conditions.

  13. 2009 Spring floods in North Dakota, western Minnesota, and northeastern South Dakota

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    Macek-Rowland, Kathleen M.; Gross, Tara A.

    2011-01-01

    In 2009, record-breaking snowfalls and additional spring moisture caused severe flooding in parts of the Missouri River and Red River of the North (Red River) Basins in North Dakota, Minnesota, and South Dakota. There were 48 peak of record stages and 36 discharges recorded at U.S. Geological Survey streamgages located in both basins between March 20 and May 15, 2009. High water continued to affect many communities up and down the rivers' main stems and tributaries for nearly 2 months. Record snowfall for single-day totals, as well as monthly totals, occurred throughout the Missouri River and Red River of the North Basins. Additional moisture in the spring as well as the timing of warmer temperatures caused record flooding in many places in both basins with many locations reporting two flood crests. Ice jams on the Missouri River, located north and south of Bismarck, N. Dak., caused flooding. Southwest Bismarck was evacuated as rising waters first began inundating homes in low-lying areas along the river and then continued flowing into the city's lower south side. On March 24, 2009, the peak stage of the Missouri River at Bismarck, N. Dak. streamgage was 16.11 feet, which was the highest recorded stage since the completion of Garrison Dam in 1954. South of Bismarck, the Missouri River near Schmidt, N. Dak. streamgage recorded a peak stage of 24.24 feet on March 25, 2009, which surpassed the peak of record of 23.56 feet that occurred on December 9, 1976. While peak stage reached record levels at these streamgages, the discharge through the river at these locations did not reach record levels. The record high stages resulted from ice jams occurring on the Missouri River north and south of the cities of Bismarck and Mandan. At the Red River of the North at Fargo, N. Dak. streamgage, the Red River reached a record stage of 40.84 feet surpassing the previous peak of record stage of 39.72 feet set in 1997. The associated peak streamflow of 29,500 cubic feet per second

  14. Flood analysis using HEC-RAS model: a case study for Hafr Al-Batin, Saudi Arabia

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    Al-Zahrani Muhammad

    2016-01-01

    Full Text Available Hafr Al-Batin is a Saudi Arabian city located in the northeastern part of the kingdom. The city lies in the dry valley of Wadi Al-Batin, part of Wadi Al-Rummah, which leads inland towards Medina and formerly emptied into the Arabian Gulf. Hafr Al-Batin is located in an area where three valleys meet, which makes the city under high risk of flooding, especially when intense rain occurs during short duration as in the case of arid and semi-arid regions. The yearly average rainfall intensity of Hafr Al-Baten is estimated to be 125 mm. Recently, extreme rainfall events occurred, generating flood water to flow from all valleys towards the city, causing serious damage to public and private properties. In this study, HEC-HMS and HEC-RAS models are used to simulate flood occurrence in the city. The results indicate that the average flow depths within the part of the main channel passing through Hafr Al-Batin city were 3.02 m, 3.26 m, 3.45 m, 3.76 m, 4.04 m and 4.34 m for the simulated 2, 5, 10, 25, 50 and 100-year design floods, respectively. Flood hazard maps are also generated to identify the areas within the city with high risk of flooding.

  15. Floods

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    Floods are common in the United States. Weather such as heavy rain, thunderstorms, hurricanes, or tsunamis can ... is breached, or when a dam breaks. Flash floods, which can develop quickly, often have a dangerous ...

  16. Health protection and risks for rescuers in cases of floods.

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    Janev Holcer, Nataša; Jeličić, Pavle; Grba Bujević, Maja; Važanić, Damir

    2015-03-01

    Floods can pose a number of safety and health hazards for flood-affected populations and rescuers and bring risk of injuries, infections, and diseases due to exposure to pathogenic microorganisms and different biological and chemical contaminants. The risk factors and possible health consequences for the rescuers involved in evacuation and rescuing operations during the May 2014 flood crisis in Croatia are shown, as well as measures for the prevention of injuries and illnesses. In cases of extreme floods, divers play a particularly important role in rescuing and first-response activities. Rescuing in contaminated floodwaters means that the used equipment such as diving suits should be disinfected afterwards. The need for securing the implementation of minimal health and safety measures for involved rescuers is paramount. Data regarding injuries and disease occurrences among rescuers are relatively scarce, indicating the need for medical surveillance systems that would monitor and record all injuries and disease occurrences among rescuers in order to ensure sound epidemiological data. The harmful effects of flooding can be reduced by legislation, improvement of flood forecasting, establishing early warning systems, and appropriate planning and education.

  17. Flood hazard and flood risk assessment using a time series of satellite images: a case study in Namibia.

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    Skakun, Sergii; Kussul, Nataliia; Shelestov, Andrii; Kussul, Olga

    2014-08-01

    In this article, the use of time series of satellite imagery to flood hazard mapping and flood risk assessment is presented. Flooded areas are extracted from satellite images for the flood-prone territory, and a maximum flood extent image for each flood event is produced. These maps are further fused to determine relative frequency of inundation (RFI). The study shows that RFI values and relative water depth exhibit the same probabilistic distribution, which is confirmed by Kolmogorov-Smirnov test. The produced RFI map can be used as a flood hazard map, especially in cases when flood modeling is complicated by lack of available data and high uncertainties. The derived RFI map is further used for flood risk assessment. Efficiency of the presented approach is demonstrated for the Katima Mulilo region (Namibia). A time series of Landsat-5/7 satellite images acquired from 1989 to 2012 is processed to derive RFI map using the presented approach. The following direct damage categories are considered in the study for flood risk assessment: dwelling units, roads, health facilities, and schools. The produced flood risk map shows that the risk is distributed uniformly all over the region. The cities and villages with the highest risk are identified. The proposed approach has minimum data requirements, and RFI maps can be generated rapidly to assist rescuers and decisionmakers in case of emergencies. On the other hand, limitations include: strong dependence on the available data sets, and limitations in simulations with extrapolated water depth values.

  18. Legitimate adaptive flood risk governance beyond the dikes: The cases of Hamburg, Helsinki and Rotterdam

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    Mees, H.L.P.

    2013-01-01

    This research entailed an international comparative case study on adaptive flood risk governance arrangements for urban waterfront regeneration projects. These projects apply flood risk strategies that aim to reduce the impacts of a flood in addition to preventing the occurrence of a flood so as to

  19. DERIVING FLASH FLOODS IN THE CASE OF SIMULATED PRECIPITATIONS

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    GYŐRI MARIA-MIHAELA

    2013-01-01

    Full Text Available Deriving flash floods in the case of simulated precipitations. The present study sets to determine the historical flash-floods on the Petriș watershed making use of the implemented mathematical models in a Hydrological Modeling System. In order to simulate the 1%, 2% and 10% exceedance probability flash-floods, the Intensity-Frequency-Duration (IDF curves have been built on the basis of 22 years of precipitation records (1988-2009. They serve as input data together with the hydrological parameters identified by the means of a Geographic Information Systems. The results, computed mainly on the basis of the Soil Conservation Service (SCS method, consist of hyetographs and hydrographs at the outlet of the main watershed, as well as to that of the ungauged tributaries of the Petriș River.

  20. Flood risk management: cases studies in French Mediterranean area

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    Defossez Stéphanie

    2016-01-01

    Full Text Available In France, for a long time, flood risk management has only oriented to controlling flood hazard with structural measures such as dikes. But since 1990’s many events have proved they have not totally efficient measures. So, institutions decided it’s necessary to manage flood risk with others ways like prevention. Risk management is so organize about holistic policies with different stakeholders and societies exposed at risk. Our study have the aim to demonstrate through several examples how flood risk is manage in French Mediterranean area. Post event feedback permit us to evaluate damage and crisis management. This method is use for show if this strategies is efficient or not. This study demonstrate how is risk management in France. Regulations are they efficient, so have they an influence about the reduction of deaths and damages? Individual measures are they more important than collective action? Finally, what policies and strategies are used and effective? The main results about cases studies show that natural event has most important that publics policies and it determines preventive policies.

  1. Using LiDAR surveys to document floods: A case study of the 2008 Iowa flood

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    Chen, Bo; Krajewski, Witold F.; Goska, Radek; Young, Nathan

    2017-10-01

    Can we use Light Detection and Ranging (LiDAR), an emergent remote sensing technology with wide applications, to document floods with high accuracy? To explore the feasibility of this application, we propose a method to extract distributed inundation depths from a LiDAR survey conducted during flooding. This method consists of three steps: (1) collecting LiDAR data during flooding; (2) classifying the LiDAR observational points as flooded water surface points and non-flooded points, and generating a floodwater surface elevation model; and (3) subtracting the bare earth Digital Terrain Model (DTM) from the flood surface elevation model to obtain a flood depth map. We applied this method to the 2008 Iowa flood in the United States and evaluated the results using the high-water mark measurements, flood extent extracted from SPOT (Small Programmable Object Technology) imagery, and the near-simultaneously acquired aerial photography. The root mean squared error of the LiDAR-derived floodwater surface profile to high-water marks was 30 cm, the consistency between the two flooded areas derived from LiDAR and SPOT imagery was 72% (81% if suspicious isolated ponds in the SPOT-derived extent were removed), and LiDAR-derived flood extent had a horizontal resolution of ∼3 m. This work demonstrates that LiDAR technology has the potential to provide calibration and validation reference data with appreciable accuracy for improved flood inundation modeling.

  2. Geomorphic response to an extreme flood in two mountain rivers (northeastern Sardinia, Italy): the role of geomorphic and hydraulic controlling factors

    Science.gov (United States)

    Righini, Margherita; Surian, Nicola; Wohl, Ellen; Amponsah, William; Marchi, Lorenzo; Borga, Marco

    2016-04-01

    Geomorphic response to an extreme flood in two mountain rivers (northeastern Sardinia, Italy): the role of geomorphic and hydraulic controlling factors Margherita Righini (1), Nicola Surian (1), Ellen Wohl (2), William Amponsah (3, 4), Lorenzo Marchi (3), Marco Borga (4) (1) Department of Geosciences, University of Padova, Italy, (2) Department of Geosciences, Colorado State University, Fort Collins, Colorado, USA, (3) CNR IRPI, Padova, Italy, (4) Department of Land, Environment, Agriculture and Forestry, University of Padova, Italy. The investigation of geomorphic effectiveness of extreme floods is crucial to improve tools for assessing channel dynamics and our capability of forecasting geomorphological hazard. This work deals with geomorphic response of two mountain rivers in the Posada catchment (northeastern Sardinia, Italy), considering a range of morphological (i.e., lateral channel confinement, channel gradient, channel sinuosity, sediment sources, and vegetation) and hydraulic variables (i.e., cross-sectional stream power, unit stream power, flow duration and total energy expenditure) as possible controlling factors. On November 18th 2013, northeastern Sardinia was affected by an extreme meteorological event with hourly rainfall intensities up to 100 mm/h and a peak in rain accumulation up to 450 mm in 24 hours, with 18 casualties and damages to infrastructure and buildings. In the Posada and Mannu di Bitti Rivers, the geomorphic response (i.e., bank erosion, channel aggradation and incision, vegetation and wood dynamics, hillslope failure) was analyzed at different spatial scales. The observed dominant geomorphic change was channel widening. Therefore, channel width changes have been analyzed in detail by remote sensing and GIS tools integrated by field surveys. The study focuses on reaches (i.e., 22.5 km in the Posada River, upstream of Maccheronis dam; 18.2 km in the Mannu di Bitti River) affected by evident and significant geomorphic responses in terms

  3. Winter and summer-autumn flash floods as "drivers" of drought and seasonal flood characteristics (case study of European Russia)

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    Kireeva, Maria; Frolova, Natalia; Rets, Ekaterina; Ezerova, Natalia

    2016-04-01

    The presence of occasional flood periods on rivers is a typical feature of the hydrological regime of European Russia. Despite the fact that the main high-water phase of a hydrological year here is related to spring, flash floods in other seasons play an equally important role. For example, increased water content during autumn determines soil moisture content that determines the loss of runoff during spring flood. Winter floods caused by thaws result in a significant drawdown of a snow pack. And when it is followed by a return of cold weather an ice crust is formed on the surface of snowpack that significantly reduces rates of melt water filtration process.In recent decades, most of the rivers in the European part of Russia have experienced a significant increase of occasional flood flow share in total annual runoff. For example, in the Don basin this parameter has increased by almost 2 times, in the basin of Oka by 1.5. Though less intense, these trends can be traced in the eastern part of the region - in the basins of Kama and Vyatka. The increase here can is approximately 15-20%. In the north of the Eastern Plain (North Dvina, etc.) this tendency isn't observed. The number of flood waves has several times increased. Until 1970s 1-3 occasional floods a year were generally observed on the rivers of Central and Southern Russia. In the past three decades almost every year there are from 4 to 8 or more periods of high water. They are superimposed on each other, as well as the phase of the spring flood and low flow period. The ratio of the maximum discharge of occasional flood to maximum discharge of seasonal flood has increased several times. Now some outstanding floods can be compared with the spring flood wave or even exceed it.Thus, through winter floods an "interception" of spring flood runoff occurs. Spring floods have a lower height and volume and as a result they don't fully recharge a basin. Dry period in this case begins much earlier and though the moisture

  4. Hydrological simulation of flood transformations in the upper Danube River: Case study of large flood events

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    Mitková Veronika Bačová

    2016-12-01

    Full Text Available The problem of understand natural processes as factors that restrict, limit or even jeopardize the interests of human society is currently of great concern. The natural transformation of flood waves is increasingly affected and disturbed by artificial interventions in river basins. The Danube River basin is an area of high economic and water management importance. Channel training can result in changes in the transformation of flood waves and different hydrographic shapes of flood waves compared with the past. The estimation and evolution of the transformation of historical flood waves under recent river conditions is only possible by model simulations. For this purpose a nonlinear reservoir cascade model was constructed. The NLN-Danube nonlinear reservoir river model was used to simulate the transformation of flood waves in four sections of the Danube River from Kienstock (Austria to Štúrovo (Slovakia under relatively recent river reach conditions. The model was individually calibrated for two extreme events in August 2002 and June 2013. Some floods that occurred on the Danube during the period of 1991–2002 were used for the validation of the model. The model was used to identify changes in the transformational properties of the Danube channel in the selected river reach for some historical summer floods (1899, 1954 1965 and 1975. Finally, a simulation of flood wave propagation of the most destructive Danube flood of the last millennium (August 1501 is discussed.

  5. Economic Shocks and Civil Conflict: The Case of Large Floods

    OpenAIRE

    Ghimire, Ramesh; Ferreira, Susana

    2013-01-01

    We investigate the impact of large floods on the risk of civil conflict in a sample of 125 countries between 1985 and 2009. We control for endogeneity of floods and the potential spatial and temporal dependency of civil conflict. We find that floods increase the probability of conflict incidence through a negative impact on short-run GDP growth.

  6. Measuring flood footprint of a regional economy - A case study for the UK flooding

    Science.gov (United States)

    Guan, D.

    2013-12-01

    Analysis of the urban economy and society is central to understanding the broad impacts of flooding and to identify cost-effective adaptation and mitigation measures. Assessments of the flooding impacts on cities have traditionally focused on the initial impact on people and assets. These initial estimates (so-called ';direct damage') are useful both in understanding the immediate implications of damage, and in marshalling the pools of capital and supplies required for re-building after an event. Since different economies as well as societies are coupled, especially under the current economic crisis, any small-scale damage may be multiplied and cascaded throughout wider economic systems and social networks. The direct and indirect damage is currently not evaluated well and could be captured by quantification of what we call the flood footprint. Flooding in one location can impact the whole UK economy. Neglecting these knock-on costs (i.e. the true footprint of the flood) means we might be ignoring the economic benefits and beneficiaries of flood risk management interventions. In 2007, for example, floods cost the economy about £3.2 bn directly, but the wider effect might actually add another 50% to 250% to that. Flood footprint is a measure of the exclusive total socioeconomic impact that is directly and indirectly caused by a flood event to the flooding region and wider economic systems and social networks. We adopt the UK 2012 flooding. An input-output basic dynamic inequalities (BDI) model is used to assess the impact of the floodings on the level of a Yorkshire economy, accounting for interactions between industries through demand and supply of intermediate consumption goods with a circular flow. After the disaster the economy will be unbalanced. The recovery process finishes when the economy is completely balance, i.e., when labour production capacity equals demands and production and all the variables reach pre-disaster levels. The analysis is carried out

  7. Rainfall thresholds and flood warning: an operative case study

    Directory of Open Access Journals (Sweden)

    V. Montesarchio

    2009-02-01

    Full Text Available An operative methodology for rainfall thresholds definition is illustrated, in order to provide at critical river section optimal flood warnings. Threshold overcoming could produce a critical situation in river sites exposed to alluvial risk and trigger the prevention and emergency system alert. The procedure for the definition of critical rainfall threshold values is based both on the quantitative precipitation observed and the hydrological response of the basin. Thresholds values specify the precipitation amount for a given duration that generates a critical discharge in a given cross section and are estimated by hydrological modelling for several scenarios (e.g.: modifying the soil moisture conditions. Some preliminary results, in terms of reliability analysis (presence of false alarms and missed alarms, evaluated using indicators like hit rate and false alarm rate for the case study of Mignone River are presented.

  8. A press database on natural risks and its application in the study of floods in Northeastern Spain

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    M. C. Llasat

    2009-12-01

    Full Text Available The aim of this work is to introduce a systematic press database on natural hazards and climate change in Catalonia (NE of Spain and to analyze its potential application to social-impact studies. For this reason, a review of the concepts of risk, hazard, vulnerability and social perception is also included. This database has been built for the period 1982–2007 and contains all the news related with those issues published by the oldest still-active newspaper in Catalonia. Some parameters are registered for each article and for each event, including criteria that enable us to determine the importance accorded to it by the newspaper, and a compilation of information about it. This ACCESS data base allows each article to be classified on the basis of the seven defined topics and key words, as well as summary information about the format and structuring of the new itself, the social impact of the event and data about the magnitude or intensity of the event. The coverage given to this type of news has been assessed because of its influence on construction of the social perception of natural risk and climate change, and as a potential source of information about them. The treatment accorded by the press to different risks is also considered. More than 14 000 press articles have been classified. Results show that the largest number of news items for the period 1982–2007 relates to forest fires and droughts, followed by floods and heavy rainfalls, although floods are the major risk in the region of study. Two flood events recorded in 2002 have been analyzed in order to show an example of the role of the press information as indicator of risk perception.

  9. A press database on natural risks and its application in the study of floods in Northeastern Spain

    Science.gov (United States)

    Llasat, M. C.; Llasat-Botija, M.; López, L.

    2009-12-01

    The aim of this work is to introduce a systematic press database on natural hazards and climate change in Catalonia (NE of Spain) and to analyze its potential application to social-impact studies. For this reason, a review of the concepts of risk, hazard, vulnerability and social perception is also included. This database has been built for the period 1982-2007 and contains all the news related with those issues published by the oldest still-active newspaper in Catalonia. Some parameters are registered for each article and for each event, including criteria that enable us to determine the importance accorded to it by the newspaper, and a compilation of information about it. This ACCESS data base allows each article to be classified on the basis of the seven defined topics and key words, as well as summary information about the format and structuring of the new itself, the social impact of the event and data about the magnitude or intensity of the event. The coverage given to this type of news has been assessed because of its influence on construction of the social perception of natural risk and climate change, and as a potential source of information about them. The treatment accorded by the press to different risks is also considered. More than 14 000 press articles have been classified. Results show that the largest number of news items for the period 1982-2007 relates to forest fires and droughts, followed by floods and heavy rainfalls, although floods are the major risk in the region of study. Two flood events recorded in 2002 have been analyzed in order to show an example of the role of the press information as indicator of risk perception.

  10. EXPOSURE AND VULNERABILITY TO FLOODS IN URBAN AREAS. CASE STUDY OF GALAȚI CITY (ROMANIA

    Directory of Open Access Journals (Sweden)

    GEORGIANA BĂNUC

    2014-05-01

    Full Text Available Exposure and vulnerability to floods in urban areas. Case study of Galai city (Romania. Urban flooding is among the most severe ones, since it acts on highly populated areas, with high density of socio-economic objectives. After presenting the general context of urban flooding and the specific meaning of exposure/vulnerability, the first part of this paper contextualizes the case study area: Galati city, the most important Romanian river port. The authors created a geographical information system for multilayer analysis based on simulations of potential flooding at different characteristic levels: defense, attention, flooding and danger. On this base, the main elements at risk were inventoried and interpreted according to their significance and in relation with the consequences of a real historical flooding (occurred in 2010.

  11. Coastal flood protection management under uncertainty – the Danish case

    DEFF Research Database (Denmark)

    Jumppanen Andersen, Kaija; Sørensen, Carlo Sass; Piontkowitz, Thorsten

    Local stakeholders responsible for coastal management. In Denmark, the responsibility of defining, planning and implementing coastal flood protection lies with the local stakeholders, such as landowners and municipalities. Similarly, it is a municipal responsibility to define building foundation...... and flood protection levels in urban planning and long term development. These planning and protection levels are most often defined from the hazard instead of a risk perspective.The Danish Coastal Authority (DCA) guides local stakeholders on general coastal flood protection and implements the EU Flood...... Directive on flood risk reduction in appointed areas of significant flood risk. DCA is obligated to communicate the concept of risk and, in a thorough and easily comprehendible way, the hazards and uncertainties relating to this today and in the future....

  12. The near-term prediction of drought and flooding conditions in the northeastern United States based on extreme phases of AMO and NAO

    Science.gov (United States)

    Berton, Rouzbeh; Driscoll, Charles T.; Adamowski, Jan F.

    2017-10-01

    A series of hydroclimatic teleconnection patterns were identified between variations in either Atlantic or Pacific oceanic indices with precipitation and discharge anomalies in the northeastern United States. We hypothesized that temporal annual or seasonal changes in discharge could be explained by variations in extreme phases of the Atlantic Multi-decadal Oscillation (AMO index, SST: Sea Surface Temperature anomalies) and the North Atlantic Oscillation (NAO index, SLP: Sea-Level Pressure anomalies) up to three seasons in advance. The Merrimack River watershed, the fourth largest basin in New England, with a drainage area of 13,000 km2, is a compelling study site because it not only provides an opportunity to investigate the teleconnection between hydrologic variables and large-scale climate circulation patterns, but also how those patterns may become obscured by anthropogenic disturbances such as river regulation or urban development. We considered precipitation and discharge data of 21 gauging stations within the Merrimack River watershed, including the Hubbard Brook Experimental Forest (HBEF), NH, with a median record length of 55 years beginning as early as 1904. The discharge anomalies were statistically significant (p-value ≤ 0.2) between extreme positive and negative phases of AMO (1857-2011) and NAO (1900-2011) and revealed the potential teleconnectivity of climate circulation patterns with discharge. Annual and seasonal correlations of discharge were examined with the extreme phases of AMO and NAO at zero-, one-, or two- year/season lags (total of 30 scenarios). When AMO was greater than 0.2, the strongest correlations of AMO and NAO with discharge were observed at headwater catchments. This correlation weakened downstream towards larger regulated and/or developed sub-basins. We introduced a simple approach for near-term prediction of drought and flooding events. An exponential decay function was regressed through the historic occurrence of the relative

  13. Flood Risk Assessment as a Part of Integrated Flood and Drought Analysis. Case Study: Southern Thailand

    Science.gov (United States)

    Prabnakorn, Saowanit; Suryadi, Fransiscus X.; de Fraiture, Charlotte

    2015-04-01

    Flood and drought are two main meteorological catastrophes that have created adverse consequences to more than 80% of total casualties universally, 50% by flood and 31% by drought. Those natural hazards have the tendency of increasing frequency and degree of severity and it is expected that climate change will exacerbate their occurrences and impacts. In addition, growing population and society interference are the other key factors that pressure on and exacerbate the adverse impacts. Consequently, nowadays, the loss from any disasters becomes less and less acceptable bringing about more people's consciousness on mitigation measures and management strategies and policies. In general, due to the difference in their inherent characteristics and time occurrences flood and drought mitigation and protection have been separately implemented, managed, and supervised by different group of authorities. Therefore, the objective of this research is to develop an integrated mitigation measure or a management policy able to surmount both problems to acceptable levels and is conveniently monitored by the same group of civil servants which will be economical in both short- and long-term. As aforementioned of the distinction of fundamental peculiarities and occurrence, the assessment processes of floods and droughts are separately performed using their own specific techniques. In the first part of the research flood risk assessment is focused in order to delineate the flood prone area. The study area is a river plain in southern Thailand where flooding is influenced by monsoon and depression. The work is mainly concentrated on physically-based computational modeling and an assortment of tools was applied for: data completion, areal rainfall interpolation, statistical distribution, rainfall-runoff analysis and flow model simulation. The outcome from the simulation can be concluded that the flood prone areas susceptible to inundation are along the riparian areas, particularly at the

  14. Flash flood hazard mapping: a pilot case study in Xiapu River Basin, China

    Directory of Open Access Journals (Sweden)

    Da-wei Zhang

    2015-07-01

    Full Text Available Flash flood hazard mapping is a supporting component of non-structural measures for flash flood prevention. Pilot case studies are necessary to develop more practicable methods for the technical support systems of flash flood hazard mapping. In this study, the headwater catchment of the Xiapu River Basin in central China was selected as a pilot study area for flash flood hazard mapping. A conceptual distributed hydrological model was developed for flood calculation based on the framework of the Xinanjiang model, which is widely used in humid and semi-humid regions in China. The developed model employs the geomorphological unit hydrograph method, which is extremely valuable when simulating the overland flow process in ungauged catchments, as compared with the original Xinanjiang model. The model was tested in the pilot study area, and the results agree with the measured data on the whole. After calibration and validation, the model is shown to be a useful tool for flash flood calculation. A practicable method for flash flood hazard mapping using the calculated peak discharge and digital elevation model data was presented, and three levels of flood hazards were classified. The resulting flash flood hazard maps indicate that the method successfully predicts the spatial distribution of flash flood hazards, and it can meet the current requirements in China.

  15. An Ecological Flood Control System in Phoenix Island of Huzhou, China: A Case Study

    Directory of Open Access Journals (Sweden)

    Zhuowen Wang

    2013-09-01

    Full Text Available Traditional flood control systems always have a conflict with natural ones, i.e., rivers in cities are usually straight and smooth, whereas natural ones are according to ecological mechanisms. Social and economic developments in the modern world require a new system combining ecological needs and traditional flood control system. Ecological flood control systems were put forward and defined as flood control systems with full consideration of ecological demands for sustainable development. In such systems, four aspects are promoted: connectivity of water system, landscapes of river and lakes, mobility of water bodies, and safety of flood control. In Phoenix Island, Huzhou, needs for ecological flood controls were analyzed from the four aspects above. The Water system layout was adjusted with the water surface ratio, which is the ratio of water surface area (including rivers, lakes, and other water bodies to the total drainage area, and connectivity as controlling indicators. The designed water levels provided references for landscape plant selection. Mobility of the adjusted water system was analyzed, including flow direction and residence time. On the bases mentioned above, ecological flood control projects were planned with comprehensive consideration of the ecological requirements. The case study indicates that ecological needs can be integrated with flood control to develop ecological flood control systems that do not only prevent floods but also retain the ecological functions of water bodies.

  16. Urban Flood Vulnerability and Risk Mapping Using Integrated Multi-Parametric AHP and GIS: Methodological Overview and Case Study Assessment

    OpenAIRE

    2014-01-01

    This study aims at providing expertise for preparing public-based flood mapping and estimating flood risks in growing urban areas. To model and predict the magnitude of flood risk areas, an integrated Analytical Hierarchy Process (AHP) and Geographic Information System (GIS) analysis techniques are used for the case of Eldoret Municipality in Kenya. The flood risk vulnerability mapping follows a multi-parametric approach and integrates some of the flooding causative factors such as rainfall d...

  17. Trends in flash flood events versus convective precipitation in the Mediterranean region: The case of Catalonia

    Science.gov (United States)

    Llasat, Maria Carmen; Marcos, Raul; Turco, Marco; Gilabert, Joan; Llasat-Botija, Montserrat

    2016-10-01

    The aim of this paper is to analyse the potential relationship between flash flood events and convective precipitation in Catalonia, as well as any related trends. The paper starts with an overview of flash floods and their trends in the Mediterranean region, along with their associated factors, followed by the definition of, identification of, and trends in convective precipitation. After this introduction the paper focuses on the north-eastern Iberian Peninsula, for which there is a long-term precipitation series (since 1928) of 1-min precipitation from the Fabra Observatory, as well as a shorter (1996-2011) but more extensive precipitation series (43 rain gauges) of 5-min precipitation. Both series have been used to characterise the degree of convective contribution to rainfall, introducing the β parameter as the ratio between convective precipitation versus total precipitation in any period. Information about flood events was obtained from the INUNGAMA database (a flood database created by the GAMA team), with the aim of finding any potential links to convective precipitation. These flood data were gathered using information on damage where flood is treated as a multifactorial risk, and where any trend or anomaly might have been caused by one or more factors affecting hazard, vulnerability or exposure. Trend analysis has shown an increase in flash flood events. The fact that no trends were detected in terms of extreme values of precipitation on a daily scale, nor on the associated ETCCDI (Expert Team on Climate Change Detection and Indices) extreme index, could point to an increase in vulnerability, an increase in exposure, or changes in land use. However, the summer increase in convective precipitation was concentrated in less torrential events, which could partially explain this positive trend in flash flood events. The β parameter has been also used to characterise the type of flood event according to the features of the precipitation. The highest values

  18. Urbanism, climate change and floods: Case of Tlemcen city

    Directory of Open Access Journals (Sweden)

    Hayat Adjim

    2018-03-01

    Full Text Available After a drought during the 1990s, Tlemcen has experienced heavy rainfall in recent years which caused several floods. They have become frequent and usually cause large damage. We then asked ourselves questions about the reasons for this deregulation of rainfall and floods. We have assumed that climate change has led to deregulation of precipitation and that the urbanization and morphology of the site are the causes of the floods. For this, we analyzed the rainfall data and study the configuration of the town of Tlemcen. We noticed then that Tlemcen town undergoes the climate changes effects per a diminution of the multi-annual mean of rainfall between 1974 and 2008, and a slight displacement of the rainfall from April to November after 2008. Finally, the principal reason of floods is the thoughtless urban sprawl on the water courses also favored by an unfavourable topography.

  19. Flood marks of the 1813 flood in the Central Europe

    Science.gov (United States)

    Miklanek, Pavol; Pekárová, Pavla; Halmová, Dana; Pramuk, Branislav; Bačová Mitková, Veronika

    2014-05-01

    In August 2013, 200 years have passed since the greatest and most destructive floods known in the Slovak river basins. The flood affected almost the entire territory of Slovakia, northeastern Moravia, south of Poland. River basins of Váh (Orava, Kysuca), Poprad, Nitra, Hron, Torysa, Hornád, upper and middle Vistula, Odra have been most affected. The aim of this paper is to map the flood marks documenting this catastrophic flood in Slovakia. Flood marks and registrations on the 1813 flood in the Váh river basin are characterized by great diversity and are written in Bernolák modification of Slovak, in Latin, German and Hungarian. Their descriptions are stored in municipal chronicles and Slovak and Hungarian state archives. The flood in 1813 devastated the entire Váh valley, as well as its tributaries. Following flood marks were known in the Vah river basin: Dolná Lehota village in the Orava river basin, historical map from 1817 covering the Sučany village and showing three different cross-sections of the Váh river during the 1813 flood, flood mark in the city of Trenčín, Flood mark in the gate of the Brunovce mansion, cross preserved at the old linden tree at Drahovce, and some records in written documents, e.g. Cifer village. The second part of the study deals with flood marks mapping in the Hron, Hnilec and Poprad River basins, and Vistula River basin in Krakow. On the basis of literary documents and the actual measurement, we summarize the peak flow rates achieved during the floods in 1813 in the profile Hron: Banská Bystrica. According to recent situation the 1813 flood peak was approximately by 1.22 m higher, than the flood in 1974. Also in the Poprad basin is the August 1813 flood referred as the most devastating flood in last 400 years. The position of the flood mark is known, but the building was unfortunately removed later. The water level in 1813 was much higher than the water level during the recent flood in June 2010. In Cracow the water level

  20. Flood monitoring and damage assessment using water indices: A case study of Pakistan flood-2012

    Directory of Open Access Journals (Sweden)

    Akhtar Ali Memon

    2015-06-01

    Full Text Available This paper uses Normalized Difference Water Index (NDWI of McFeeters (1996, Water Index (WI introduced by Rogers and Kearney (2004, referred to as Red and Short Wave Infra-Red (RSWIR and WI suggested as the best by Ji et al. (2009, referred to as Green and Short Wave Infra-Red (GSWIR for delineating and mapping of surface water using MODIS (Terra near real time images during 2012 floods in Pakistan. The results from above indices have been compared with Landsat ETM+ classified images aiming to assess the accuracy of the indices. Accuracy assessment has been performed using spatial statistical techniques and found NDWI, RSWIR and GSWIR with kappa coefficient (κ of 46.66%, 70.80% and 60.61% respectively. It has been observed using statistical analysis and visual interpretation (expert knowledge gained by past experience that the NDWI and GSWIR have tendencies to underestimate and overestimate respectively the inundated area. Keeping in view the above facts, RSWIR has proved to be the best of the three indices. In addition, assessment of the damages has been carried out considering accumulated flood extent obtained from RSWIR. The information derived proved to be essential and valuable for disaster management plan and rehabilitation.

  1. How Multilevel Societal Learning Processes Facilitate Transformative Change: A Comparative Case Study Analysis on Flood Management

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    Claudia Pahl-Wostl

    2013-12-01

    Full Text Available Sustainable resources management requires a major transformation of existing resource governance and management systems. These have evolved over a long time under an unsustainable management paradigm, e.g., the transformation from the traditionally prevailing technocratic flood protection toward the holistic integrated flood management approach. We analyzed such transformative changes using three case studies in Europe with a long history of severe flooding: the Hungarian Tisza and the German and Dutch Rhine. A framework based on societal learning and on an evolutionary understanding of societal change was applied to identify drivers and barriers for change. Results confirmed the importance of informal learning and actor networks and their connection to formal policy processes. Enhancing a society's capacity to adapt is a long-term process that evolves over decades, and in this case, was punctuated by disastrous flood events that promoted windows of opportunity for change.

  2. A framework for the case-specific assessment of Green Infrastructure in mitigating urban flood hazards

    Science.gov (United States)

    Schubert, Jochen E.; Burns, Matthew J.; Fletcher, Tim D.; Sanders, Brett F.

    2017-10-01

    This research outlines a framework for the case-specific assessment of Green Infrastructure (GI) performance in mitigating flood hazard in small urban catchments. The urban hydrologic modeling tool (MUSIC) is coupled with a fine resolution 2D hydrodynamic model (BreZo) to test to what extent retrofitting an urban watershed with GI, rainwater tanks and infiltration trenches in particular, can propagate flood management benefits downstream and support intuitive flood hazard maps useful for communicating and planning with communities. The hydrologic and hydraulic models are calibrated based on current catchment conditions, then modified to represent alternative GI scenarios including a complete lack of GI versus a full implementation of GI. Flow in the hydrologic/hydraulic models is forced using a range of synthetic rainfall events with annual exceedance probabilities (AEPs) between 1-63% and durations from 10 min to 24 h. Flood hazard benefits mapped by the framework include maximum flood depths and extents, flow intensity (m2/s), flood duration, and critical storm duration leading to maximum flood conditions. Application of the system to the Little Stringybark Creek (LSC) catchment shows that across the range of AEPs tested and for storm durations equal or less than 3 h, presently implemented GI reduces downstream flooded area on average by 29%, while a full implementation of GI would reduce downstream flooded area on average by 91%. A full implementation of GI could also lower maximum flow intensities by 83% on average, reducing the drowning hazard posed by urban streams and improving the potential for access by emergency responders. For storm durations longer than 3 h, a full implementation of GI lacks the capacity to retain the resulting rainfall depths and only reduces flooded area by 8% and flow intensity by 5.5%.

  3. Neurocysticercosis in Ceará State, northeastern Brazil: a review of 119 cases.

    Science.gov (United States)

    Sousa, A Q; Sa, H L; Queiroz, T R; Horta, W G; Pearson, R D

    1998-06-01

    Relatively little is known about the occurrence of neurocysticercosis in northeastern Brazil. There have been no published reports from the state of Ceará, but a review of the records at the Hospital São José in Fortaleza, Brazil identified 119 patients with neurocysticercosis diagnosed between January 1988 and April 1994. Patients came from 43 municipalities in Ceará. Their ages ranged from five to 74 years; the greatest number of cases were in persons 10-40 years of age; 63% were males. Seizures were the presenting complaint in 64% of the patients and headache in 22%. Two patients, each with several hundred intracranial lesions, presented with mental status changes; one was initially given the clinical diagnosis of viral meningoencephalitis. Computed tomography scans showed that 44% of the patients had five or more lesions. Cysts were found throughout the brain. The parietal lobe was the most frequent site of involvement; 85% of patients had one or more lesions there. The brain stem was involved in 8%. There was no consistent association between the severity of the clinical abnormalities and the radiologic findings. Computed tomography of the thighs was done in 10 persons; cysts were identified in nine.

  4. Amyotrophic lateral sclerosis: clinical analysis of 78 cases from Fortaleza (Northeastern Brazil

    Directory of Open Access Journals (Sweden)

    CASTRO-COSTA CARLOS M. DE

    1999-01-01

    Full Text Available We report on the clinical characteristics of amyotrophic lateral sclerosis (ALS in Fortaleza (Northeastern Brazil. For this, we analyzed retrospectively (from 1980 to 1999 78 cases of ALS from the Service of Neurology of the University Hospital of Fortaleza diagnosed clinically and laboratorially (EMG, muscle biopsy, myelography, blood biochemistry, muscle enzymes and cranio-cervical X-ray. The results showed that they were mostly sporadic ALS (76/78, and they were divided into definite (n= 36, probable (n= 20, possible (n= 15 and suspected (n= 7, according to the level of diagnostic certainty. They were also subdivided into juvenile (n= 17, early-onset adult (n= 18, age-specific (n= 39 and late-onset (n= 4 groups. Clinically, they presented as initials symptoms, principally, asymmetrical (30/78 and symmetrical (24/78 weakness of extremities, besides bulbar signs, fasciculations, and atrophy. Curiously, pain as first symptom occurred in an expressive fashion (17/78. The predominant initial anatomic site, in this series, was the spinal cord, and mainly affecting the arms. As to the symptom accrual from region to region, this occurs more quickly in contiguous areas, and fasciculations are predominant when bulbar region was associated.

  5. Flooding and emergency room visits for gastrointestinal illness in Massachusetts: a case-crossover study.

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    Timothy J Wade

    Full Text Available INTRODUCTION: Floods and other severe weather events are anticipated to increase as a result of global climate change. Floods can lead to outbreaks of gastroenteritis and other infectious diseases due to disruption of sewage and water infrastructure and impacts on sanitation and hygiene. Floods have also been indirectly associated with outbreaks through population displacement and crowding. METHODS: We conducted a case-crossover study to investigate the association between flooding and emergency room visits for gastrointestinal illness (ER-GI in Massachusetts for the years 2003 through 2007. We obtained ER-GI visits from the State of Massachusetts and records of floods from the National Oceanic and Atmospheric Association's Storm Events Database. ER-GI visits were considered exposed if a flood occurred in the town of residence within three hazard periods of the visit: 0-4 days; 5-9 days; and 10-14 days. A time-stratified bi-directional design was used for control selection, matching on day of the week with two weeks lead or lag time from the ER-GI visit. Fixed effect logistic regression models were used to estimate the risk of ER-GI visits following the flood. RESULTS AND CONCLUSIONS: A total of 270,457 ER-GI visits and 129 floods occurred in Massachusetts over the study period. Across all counties, flooding was associated with an increased risk for ER-GI in the 0-4 day period after flooding (Odds Ratio: 1.08; 95% Confidence Interval: 1.03-1.12; but not the 5-9 days (Odds Ratio: 0.995; 95% Confidence Interval: 0.955-1.04 or the 10-14 days after (Odds Ratio: 0.966, 95% Confidence Interval: 0.927-1.01. Similar results were observed for different definitions of ER-GI. The effect differed across counties, suggesting local differences in the risk and impact of flooding. Statewide, across the study period, an estimated 7% of ER-GI visits in the 0-4 days after a flood event were attributable to flooding.

  6. Urban and peri-urban flood impact change: the case of the Metropolitan Area of Barcelona

    Science.gov (United States)

    Cortès, Maria; Gilabert, Joan; Llasat-Botija, Montserrat; Marcos, Raül; Llasat, Maria del Carmen

    2017-04-01

    Floods are the most important natural hazard in the world. Nowadays, mitigation and adaptation strategies to reduce the impact that climate change will have on them, are a priority in most government agendas. Recent reports from the IPCC (2012, 2014) still show significant uncertainty associated with future projections of precipitation extremes. This uncertainty is higher when referred to floods and even larger when interactions with society and the changes in vulnerability are considered. Consequently, there is now a call to treat floods from a holistic perspective that integrates bottom-up (from impact and vulnerability) and top-down (from hazard) approaches (Hall et al., 2014). The study of flood risk in urban and peri-urban areas is complex and involves multiple factors. This is the case of the Metropolitan Area of Barcelona (AMB), which concentrates 43% of total population of Catalonia in less than 2% of the whole territory. The impervious soil has grown more than 200% from 1956 to 2009 (resulting in higher values of runoff), the population has increased more than 80% in the same period and, simultaneously, an improvement of the drainage system and flood prevention has been developed. As a result, we have seen that the flood risk evolution in the area holds a strong link to these human changes. Actually, floods in this region are usually due to drainage problems, flash floods in ungauged torrential catchments and, only in some occasions, river floods are produced (i.e. the Llobregat River on September 1971). But, in all the cases they are due to heavy precipitations. The main objective of the contribution is assessing the relationship between precipitation in the AMB and the social impacts produced. In order to do it, different impact indicators have been proposed, such as the population affected or the duration of the flood event (Merz et al., 2010). These indicators have been implemented for the different cases analyzed, which affected AMB for the period

  7. THE ASSESSMENT OF ECONOMICAL LOSS CAUSED BY FLOODS AND FLASH-FLOODS BY USING COMPUTER TECHNIQUES. CASE STUDY: LOPĂTARI VILLAGE, SLĂNIC RIVER

    Directory of Open Access Journals (Sweden)

    COSTACHE R.

    2015-03-01

    Full Text Available The present study aims to provide an example of the assessment of economical loss caused by floods and flash-floods, by integrating GIS techniques of hydraulic and hydrological modelling. The case study was performed in Lopătari village, which is located in the upper area of Slănic River, one of the most affected areas by floods and flash-floods. The flood event produced on 29.V.2012 was considered in order to perform this study. Thus, a flood hydrograph was simulated by using software HEC-HMS 3.5, based on hourly precipitation data from Bisoca meteorological station from 29.V.2012. The peak discharge resulting from the hydrological modelling software was used in HEC-RAS 4.1 hydraulic modelling software in order to determine the extent of flooding band, the number of the affected elements and the local economical loss. Finally, 21 flooded buildings were identified and 550 m of affected road, the estimated economical damage being about 800,000 RON.

  8. From holy war to opium war? A case study of the opium economy in north-eastern Afghanistan.

    Science.gov (United States)

    Goodhand, J

    2000-06-01

    This paper examines the recent growth of the opium economy in north-eastern Afghanistan. A detailed analysis of one village in Badakshan Province reveals profound changes in the local economy and social institutions. The paper describes two major shifts in the local economy: first, the switch from wheat to poppy cultivation; and second, the shift from the livestock trade to the opium trade. It then examines the underlying causes and impacts of the opium economy on social relations in the village. Although a case study of a community living on the margins of the global economy, it is argued that these changes have important implications for international policymakers. The emergence of the opium economy in north-eastern Afghanistan is symptomatic of new and expanding forms of trans-border trade associated with the restructuring of the global political economy.

  9. Impacts of a flash flood on drinking water quality: case study of areas most affected by the 2012 Beijing flood.

    Science.gov (United States)

    Sun, Rubao; An, Daizhi; Lu, Wei; Shi, Yun; Wang, Lili; Zhang, Can; Zhang, Ping; Qi, Hongjuan; Wang, Qiang

    2016-02-01

    In this study, we present a method for identifying sources of water pollution and their relative contributions in pollution disasters. The method uses a combination of principal component analysis and factor analysis. We carried out a case study in three rural villages close to Beijing after torrential rain on July 21, 2012. Nine water samples were analyzed for eight parameters, namely turbidity, total hardness, total dissolved solids, sulfates, chlorides, nitrates, total bacterial count, and total coliform groups. All of the samples showed different degrees of pollution, and most were unsuitable for drinking water as concentrations of various parameters exceeded recommended thresholds. Principal component analysis and factor analysis showed that two factors, the degree of mineralization and agricultural runoff, and flood entrainment, explained 82.50% of the total variance. The case study demonstrates that this method is useful for evaluating and interpreting large, complex water-quality data sets.

  10. Impacts of a flash flood on drinking water quality: case study of areas most affected by the 2012 Beijing flood

    Directory of Open Access Journals (Sweden)

    Rubao Sun

    2016-02-01

    Full Text Available In this study, we present a method for identifying sources of water pollution and their relative contributions in pollution disasters. The method uses a combination of principal component analysis and factor analysis. We carried out a case study in three rural villages close to Beijing after torrential rain on July 21, 2012. Nine water samples were analyzed for eight parameters, namely turbidity, total hardness, total dissolved solids, sulfates, chlorides, nitrates, total bacterial count, and total coliform groups. All of the samples showed different degrees of pollution, and most were unsuitable for drinking water as concentrations of various parameters exceeded recommended thresholds. Principal component analysis and factor analysis showed that two factors, the degree of mineralization and agricultural runoff, and flood entrainment, explained 82.50% of the total variance. The case study demonstrates that this method is useful for evaluating and interpreting large, complex water-quality data sets.

  11. Case study: A severe hailstorm and strong downbursts over northeastern Slovenia on June 16th 2009

    Science.gov (United States)

    Korosec, M.

    2009-09-01

    Introduction A strong isolated storm complex with bow echo feature crossed northeastern Slovenia in the late afternoon hours and caused extensive damage due to severe wind gusts near 30m/s, excessive rainfalls and large hail. Synoptic situation On June 16th 2009, an upper-level ridge persists over southern Europe while a positively tilted short-wave trough, connected to a complex deep trough over northern Europe, crosses central Europe. Accompanied by this trough, a cold front is extending southwestwards towards the Alps. A relatively strong jet steak wraps around the trough axis and creates strong shear environment which overlaps with a narrow band of unstable airmass present ahead of the coming frontal boundary. Behind this trough/front over central Europe, a high pressure area is developing with stable conditions. Over Slovenia, strong surface heating was on going through the day but lack of near-surface convergence zones, limited moisture and strong capping inversion surpressed any storm initiation in the afternoon. Presentation of research This case study will go through a research of damaging bow echo which caused extensive damage due to severe winds, excessive rainfalls and large hail over much of northeastern Slovenia. Numerous trees were down or uprooted and numerous roofs were blown off or were seriously damaged due to severe wind gusts near or exceeding 30m/s. At first stages, when an isolated severe storm entered Slovenia, it had classic high precipitation supercell features while it transformed into a powerful bow echo later on. Very large hail up to 6cm in diameter was first observed in southeast Austria and near the border with Slovenia, while later on the main threat was very strong wind gusts and intense rainfalls. This research paper will show a detailed analysis of the synoptic situation including analysis of satellite, radar and surface observations. Radar imagery clearly showed isolated storm trailing along the near-surface frontal boundary as

  12. MODIS-based multi-parametric platform for mapping of flood affected areas. Case study: 2006 Danube extreme flood in Romania

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    Craciunescu Vasile

    2016-12-01

    Full Text Available Flooding remains the most widely distributed natural hazard in Europe, leading to significant economic and social impact. Earth observation data is presently capable of making fundamental contributions towards reducing the detrimental effects of extreme floods. Technological advance makes development of online services able to process high volumes of satellite data without the need of dedicated desktop software licenses possible. The main objective of the case study is to present and evaluate a methodology for mapping of flooded areas based on MODIS satellite images derived indices and using state-of-the-art geospatial web services. The methodology and the developed platform were tested with data for the historical flood event that affected the Danube floodplain in 2006 in Romania. The results proved that, despite the relative coarse resolution, MODIS data is very useful for mapping the development flooded area in large plain floods. Moreover it was shown, that the possibility to adapt and combine the existing global algorithms for flood detection to fit the local conditions is extremely important to obtain accurate results.

  13. Patterns of nutrient transfer in lowland catchments : A case study from northeastern Europe

    NARCIS (Netherlands)

    Mourad, D.S.J.

    2008-01-01

    Although nitrogen (N) and phosphorus (P) emissions from agricultural diffuse sources and point emissions decreased dramatically after the political and economic changes in northeastern Europe in the beginning of the 1990s, the reaction of stream water quality is often limited or absent. This holds i

  14. The Impact of the Extreme Amazonian Flood Season on the Incidence of Viral Gastroenteritis Cases.

    Science.gov (United States)

    Vieira, Carmen Baur; de Abreu Corrêa, Adriana; de Jesus, Michele Silva; Luz, Sérgio Luiz Bessa; Wyn-Jones, Peter; Kay, David; Rocha, Mônica Simões; Miagostovich, Marize Pereira

    2017-06-01

    During the Amazonian flood season in 2012, the Negro River reached its highest level in 110 years, submerging residential and commercial areas which appeared associated with an elevation in the observed gastroenteritis cases in the city of Manaus. The aim of this study was to evaluate the microbiological water quality of the Negro River basin during this extreme flood to investigate this apparent association between the illness cases and the population exposed to the contaminated waters. Forty water samples were collected and analysed for classic and emerging enteric viruses. Human adenoviruses, group A rotaviruses and genogroup II noroviruses were detected in 100, 77.5 and 27.5% of the samples, respectively, in concentrations of 10(3)-10(6) GC/L. All samples were compliant with local bacteriological standards. HAdV2 and 41 and RVA G2, P[6], and P[8] were characterised. Astroviruses, sapoviruses, genogroup IV noroviruses, klasseviruses, bocaviruses and aichiviruses were not detected. Statistical analyses showed correlations between river stage level and reported gastroenteritis cases and, also, significant differences between virus concentrations during this extreme event when compared with normal dry seasons and previous flood seasons of the Negro River. These findings suggest an association between the extreme flood experienced and gastrointestinal cases in the affected areas providing circumstantial evidence of causality between the elevations in enteric viruses in surface waters and reported illness.

  15. Performance of the ARPA-SMR limited-area ensemble prediction system: two flood cases

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    A. Montani

    2001-01-01

    Full Text Available The performance of the ARPA-SMR Limited-area Ensemble Prediction System (LEPS, generated by nesting a limited-area model on selected members of the ECMWF targeted ensemble, is evaluated for two flood events that occurred during September 1992. The predictability of the events is studied for forecast times ranging from 2 to 4 days. The extent to which floods localised in time and space can be forecast at high resolution in probabilistic terms was investigated. Rainfall probability maps generated by both LEPS and ECMWF targeted ensembles are compared for different precipitation thresholds in order to assess the impact of enhanced resolution. At all considered forecast ranges, LEPS performs better, providing a more accurate description of the event with respect to the spatio-temporal location, as well as its intensity. In both flood cases, LEPS probability maps turn out to be a very valuable tool to assist forecasters to issue flood alerts at different forecast ranges. It is also shown that at the shortest forecast range, the deterministic prediction provided by the limited area model, when run in a higher-resolution configuration, provides a very accurate rainfall pattern and a good quantitative estimate of the total rainfall deployed in the flooded regions.

  16. The KULTURisk Regional Risk Assessment methodology for flood risk: the case of Sihl river in Zurich

    Science.gov (United States)

    Ronco, Paolo; Bullo, Martina; Gallina, Valentina; Torresan, Silvia; Critto, Andrea; Zabeo, Alex; Semenzin, Elena; Buchecker, Matthias; Marcomini, Antonio

    2014-05-01

    In recent years, the frequency of catastrophes induced by natural hazard has increased and flood events in particular have been recognized as one of the most threatening water-related disasters. Severe floods have occurred in Europe over the last decade causing loss of life, displacement of people and heavy economic losses. Flood disasters are growing as a consequence of many factors both climatic and non-climatic. Indeed, the current increase of water-related disasters can be mainly attributed to the increase of exposure (elements potentially at risk in floodplains area) and vulnerability (i.e. economic, social, geographic, cultural, and physical/environmental characteristics of the exposure). Besides these factors, the strong effect of climate change is projected to radically modify the usual pattern of the hydrological cycle by intensifying the frequency and severity of flood events both at local, regional and global scale. Within this context, it is necessary to develop effective and pro-active strategies, tools and actions which allow to assess and (possibly) to reduce the risk of floods. In light of the recent European Flood Directive (FD), the KULTURisk-FP7 Project developed a state-of-the-art Regional Risk Assessment (RRA) methodology for assessing the risk imposed by floods events. The KULTURisk RRA methodology is based on the concept of risk being function of hazard, exposure and vulnerability. It is a flexible that can be adapted to different case studies (i.e. large rivers, alpine/mountain catchments, urban areas and coastal areas) and spatial scales (i.e. from the large river to the urban scale) that integrates the outputs of various hydrodynamics models (hazard) with sito-specific geophysical and socio-economic indicators (exposure and vulnerability factors such as land cover, slope, soil permeability, population density, economic activities, etc.). The main outputs of the methodology are GIS-based risk maps that identify and prioritize relative hot

  17. How do we best estimate fluvial flood risk in urban environments? : The case of the city of Eilenburg, Germany

    Science.gov (United States)

    Longo, Elisa; Tito Aronica, Giuseppe; Di Baldassarre, Giuliano; Mukolwe, Micah

    2015-04-01

    Flooding is one of the most impactful natural hazards. In particular, by looking at the data of damages from natural hazards in Europe collected in the International Disaster Database (EM-DAT) one can see a significant increase over the past four decades of both frequency of floods and associated economic damages. Similarly, dramatic trends are also found by analyzing other types of flood losses, such as the number of people affected by floods, homeless, injured or killed. To deal with the aforementioned increase of flood risk, more and more efforts are being made to promote integrated flood risk management, for instance, at the end of 2007, the European Community (EC) issued the Flood Directive (F.D.) 2007/60/EC. One of the major innovations was that the F.D. 2007/60/C requires Member State to carry out risk maps and then take appropriate measures to reduce the evaluated risk. The main goal of this research was to estimate flood damaging using a computer code based on a recently developed method (KULTURisk, www.kulturisk.eu) and to compare the estimated damage with the observed one. The study area was the municipality of Eilenburg, which in 2002 was subjected to a destructive flood event. Were produced flood damage maps with new procedures (e.g. KULTURisk) and compared the estimates with observed data. This study showed the possibility to extend the lesson learned with the Eilenburg case study in other similar contexts. The outcomes of this test provided interesting insights about the flood risk mapping, which are expected to contribute to raise awareness to the flooding issues,to plan (structural and/or non-structural) measures of flood risk reduction and to support better land-use and urban planning.

  18. Development of regional growth centres and impact on regional growth: A case study of Thailand’s Northeastern region

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    Nattapon Sang-arun

    2013-01-01

    Full Text Available This study investigates the spatial economic structure and inequality in Thailand at the national and regional levels, with a particular focus on the Northeastern region in the period from 1987 to 2007. The study has three main points: 1 examination of the economic structure and inequality at the national level and in the Northeastern region according to the Theil index, 2 determination of regional growth centres and satellite towns by using growth pole theory as a conceptual framework and incorporating spatial interaction analysis and 3 analysis of the relationship between regional growth centres and satellite towns with regard to the impact on growth and inequality. The results show that the Northeastern region is definitely the lagging region in the nation, by both gross domestic product (GDP and gross regional product (GRP per capita. It was therefore selected for a case study. Spatial analysis identified Nakhon Ratchasima, Khon Kaen, Udon Thani and Ubon Ratchathani as regional growth centres. Each of them has its own sphere of influence (or satellite towns, and the total area of regional growth centres and satellite towns are classified as sub-regions. The development of regional growth centres has a direct impact on sub-regional economic growth through economic and social relationships: urbanisation, industrial development, per capita growth, the number of higher educational institutes and so on. However, such growth negatively correlates with economic equality among the provinces in a sub-region. The inequality trend is obviously on an upswing. This study suggests that industrial links between regional growth centres and their satellite towns should be improved in order for regional growth centre development to have a consistently desirable effect on both economic growth and equality. Such a strong process means that the growth of regional growth centres will spread, leading to the development of their surrounding areas.

  19. A Mediterranean case study of flood evolution: the Metropolitan Area of Barcelona

    Science.gov (United States)

    Llasat, Maria Carmen; Gilabert, Joan; Llasat-Botija, Montserrat; Cortès, Maria; Marcos, Raül; Martín-Vide, Juan Pedro; Turco, Marco; Falcón, Lluis

    2016-04-01

    ensemble of regional models (ENSEMBLES project) have been also considered. Flood events have been obtained from newspapers, reports and insurance data. The role played by prevention measures, particularly in the specific case of Barcelona, which has been recognized by UNISDR (United Nations International Strategy for Disaster Reduction) as resilient city in front of floods, is also presented. Results confirm the strong role played by the increase of urban surface (from less than 15% in 1956 to near 40% in 2009) and explore future adaptation measures in the context of the 2030 Agenda for Sustainable Development. This work has been supported by the Spanish project HOPE and the Metropolitan Area of Barcelona, and developed by an interdisciplinary team that include experts from hydrology, meteorology, geography, environmental sciences and architecture.

  20. Watershed basin management and agriculture practices: an application case for flooding areas in Piemonte.

    Science.gov (United States)

    Bianco, G.; Franzi, L.; Valvassore, U.

    2009-04-01

    Watershed basin management in Piemonte (Italy) is a challenging issue that forces the local Authorities to a careful land planning in the frame of a sustainable economy. Different and contrasting objectives should be taken into account and balanced in order to find the best or the most "reasonable" choice under many constraints. Frequently the need for flood risk reduction and the demand for economical exploitation of floodplain areas represent the most conflicting aspects that influence watershed management politics. Actually, flood plains have been the preferred places for socio-economical activities, due to the availability of water, fertility of soil and the easiness of agricultural soil exploitation. Sometimes the bed and planform profile adjustments of a river, as a consequence of natural processes, can impede some anthropogenic activities in agriculture, such as the erosion of areas used for crops, the impossibility of water diversion, the deposition of pollutants on the ground, with effects on the economy and on the social life of local communities. In these cases watershed basin management should either balance the opposite demands, as the protection of economic activities (that implies generally canalized rivers and levees construction) and the need of favouring the river morphological stability, allowing the flooding in the inundation areas. In the paper a case study in Piemonte region (Tortona irrigation district) is shown and discussed. The effects of the Scrivia river planform adjustment on water diversion and soil erodibility force the local community and the authority of the irrigation district to ask for flood protection and river bed excavation. A mathematical model is also applied to study the effects of local river channel excavation on flood risk. Some countermeasures are also suggested to properly balance the opposite needs in the frame of a watershed basin management.

  1. Interventionist and participatory approaches to flood risk mitigation decisions: two case studies in the Italian Alps

    Science.gov (United States)

    Bianchizza, C.; Del Bianco, D.; Pellizzoni, L.; Scolobig, A.

    2012-04-01

    Flood risk mitigation decisions pose key challenges not only from a technical but also from a social, economic and political viewpoint. There is an increasing demand for improving the quality of these processes by including different stakeholders - and especially by involving the local residents in the decision making process - and by guaranteeing the actual improvement of local social capacities during and after the decision making. In this paper we analyse two case studies of flood risk mitigation decisions, Malborghetto-Valbruna and Vipiteno-Sterzing, in the Italian Alps. In both of them, mitigation works have been completed or planned, yet following completely different approaches especially in terms of responses of residents and involvement of local authorities. In Malborghetto-Valbruna an 'interventionist' approach (i.e. leaning towards a top down/technocratic decision process) was used to make decisions after the flood event that affected the municipality in the year 2003. In Vipiteno-Sterzing, a 'participatory' approach (i.e. leaning towards a bottom-up/inclusive decision process) was applied: decisions about risk mitigation measures were made by submitting different projects to the local citizens and by involving them in the decision making process. The analysis of the two case studies presented in the paper is grounded on the results of two research projects. Structured and in-depth interviews, as well as questionnaire surveys were used to explore residents' and local authorities' orientations toward flood risk mitigation. Also a SWOT analysis (Strengths, Weaknesses, Opportunities and Threats) involving key stakeholders was used to better understand the characteristics of the communities and their perception of flood risk mitigation issues. The results highlight some key differences between interventionist and participatory approaches, together with some implications of their adoption in the local context. Strengths and weaknesses of the two approaches

  2. Floods and Flash Flooding

    Science.gov (United States)

    Floods and flash flooding Now is the time to determine your area’s flood risk. If you are not sure whether you ... If you are in a floodplain, consider buying flood insurance. Do not drive around barricades. If your ...

  3. Spatio-temporal patterns of leptospirosis in Thailand: is flooding a risk factor?

    Science.gov (United States)

    Suwanpakdee, S; Kaewkungwal, J; White, L J; Asensio, N; Ratanakorn, P; Singhasivanon, P; Day, N P J; Pan-Ngum, W

    2015-07-01

    We studied the temporal and spatial patterns of leptospirosis, its association with flooding and animal census data in Thailand. Flood data from 2010 to 2012 were extracted from spatial information taken from satellite images. The incidence rate ratio (IRR) was used to determine the relationship between spatio-temporal flooding patterns and the number of human leptospirosis cases. In addition, the area of flood coverage, duration of waterlogging, time lags between flood events, and a number of potential animal reservoirs were considered in a sub-analysis. There was no significant temporal trend of leptospirosis over the study period. Statistical analysis showed an inconsistent relationship between IRR and flooding across years and regions. Spatially, leptospirosis occurred repeatedly and predominantly in northeastern Thailand. Our findings suggest that flooding is less influential in leptospirosis transmission than previously assumed. High incidence of the disease in the northeastern region is explained by the fact that agriculture and animal farming are important economic activities in this area. The periodic rise and fall of reported leptospirosis cases over time might be explained by seasonal exposure from rice farming activities performed during the rainy season when flood events often occur. We conclude that leptospirosis remains an occupational disease in Thailand.

  4. Development of a New Generation of Flood Inundation Maps—A Case Study of the Coastal City of Tainan, Taiwan

    Directory of Open Access Journals (Sweden)

    Dong-Jiing Doong

    2016-11-01

    Full Text Available Flood risk management has become a growing priority for city managers and disaster risk prevention agencies worldwide. Correspondingly, large investments are made towards data collection, archiving and analysis and technologies such as geographic information systems (GIS and remote sensing play important role in this regard. GIS technologies offer valuable means for delineation of flood plains, zoning of areas that need protection from floods and identification of plans for development and scoping of various kinds of flood protection measures. Flood inundation maps (FIMs are particularly useful in planning flood disaster risk responses. The purpose of the present paper is to describe efforts in developing new generation of FIMs at the city scale and to demonstrate effectiveness of such maps in the case of the coastal city of Tainan, Taiwan. In the present work, besides pluvial floods, the storm surge influence is also considered. The 1D/2D coupled model SOBEK was used for flood simulations. Different indicators such as Probability of Detection (POD and Scale of Accuracy (SA were applied in the calibration and validation stages of the work and their corresponding values were found to be up to 88.1% and 68.0%, respectively. From the overall analysis, it came up that land elevation, tidal phase, and storm surge are the three dominant factors that influence flooding in Tainan. A large number of model simulations were carried out in order to produce FIMs which were then effectively applied in the stakeholder engagement process.

  5. The influence of gender and age on choice of flood adaptation strategies: A case study of Zambia and Namibia..

    Science.gov (United States)

    Mabuku, Monde

    2017-04-01

    It is reported that flood events will increase due to variability and change in climate, thus increasing the number of people exposed to flooding disasters. This exposure negatively impacts rural households' livelihoods. Women, men, young, old has distinctive vulnerability and this shapes the choice of flood adaptation strategies. This calls for a need to adopt group specific interventions to strengthen local adaptive capacity to flooding for the affected population. The purpose of this case study was to determine the adaptation strategies to floods adopted by rural households in the Zambezi region of Namibia and Mwandi district of Zambia. The study further examined how gender and age influenced the choice of different adaptation strategies. Six focus group meetings and a questionnaire survey of 207 randomly sampled households were conducted in the flood prone areas of the study. Descriptive statistics results on the adaptation strategies indicated that a majority of the households in Namibia learnt to live with floods (86%),practiced mafisa cattle trade (86%), flood water harvesting (68%), practiced early and late planting (63%), prayed (55%), practiced conservation agriculture (54%) and fish farming (53%). In Zambia the adaptation strategies were; conservation agriculture (91%), acquiring better skills on preparedness (66%), flood water harvesting (63%), praying (60%), and flood proofing (52%). Logistic regression analysis showed that age positively and significantly influenced the likelihood of taking up adaptation strategies such as tree planting, relocation to higher ground, flood water harvesting, early and late planting. The older the respondents the more likely they were to adopt the strategies mentioned. More young ones were more likely to adopt acquiring better skills on flood preparedness and mafisa cattle trading than the old ones. Gender positively and significantly influenced mafisa cattle trade (pdisaster risk reduction and management in the two

  6. Building the ensemble flood prediction system by using numerical weather prediction data: Case study in Kinu river basin, Japan

    Science.gov (United States)

    Ishitsuka, Y.; Yoshimura, K.

    2016-12-01

    Floods have a potential to be a major source of economic or human damage caused by natural disasters. Flood prediction systems were developed all over the world and to treat the uncertainty of the prediction ensemble simulation is commonly adopted. In this study, ensemble flood prediction system using global scale land surface and hydrodynamic model was developed. The system requests surface atmospheric forcing and Land Surface Model, MATSIRO, calculates runoff. Those generated runoff is inputted to hydrodynamic model CaMa-Flood to calculate discharge and flood inundation. CaMa-Flood can simulate flood area and its fraction by introducing floodplain connected to river channel. Forecast leadtime was set 39hours according to forcing data. For the case study, the flood occurred at Kinu river basin, Japan in 2015 was hindcasted. In a 1761 km² Kinu river basin, 3-days accumulated average rainfall was 384mm and over 4000 people was left in the inundated area. Available ensemble numerical weather prediction data at that time was inputted to the system in a resolution of 0.05 degrees and 1hour time step. As a result, the system predicted the flood occurrence by 45% and 84% at 23 and 11 hours before the water level exceeded the evacuation threshold, respectively. Those prediction lead time may provide the chance for early preparation for the floods such as levee reinforcement or evacuation. Adding to the discharge, flood area predictability was also analyzed. Although those models were applied for Japan region, this system can be applied easily to other region or even global scale. The areal flood prediction in meso to global scale would be useful for detecting hot zones or vulnerable areas over each region.

  7. Role the Local Population in Ecotourism Development – Attitudes of Citizens Northeastern Montenegro: a Case Study

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    Goran Rajović

    2015-06-01

    Full Text Available Contemporary trends in world tourism seek spaces of the original or at least altered the environment and the chance of northeastern Montenegro, in the example of municipalities Berane, Petnjica, Andrijevica, Plav and Gusinje the choosy market may to be a destination with undisturbed ambient wholes. This paper explores the role of local people in the development of eco-tourism, and analyzed the results of surveys of environmental awareness. The survey showed the population desire for the development of eco-tourism and that they look forward to that notion. In achieving a better and higher quality of eco-tourism destination in just planning must be integrated with the local population because what is tourist’s product that is offered to the tourist market, it is the local population living space in which takes place an everyday life.

  8. Severe coinfection of melioidosis and dengue fever in northeastern Brazil: first case report

    Directory of Open Access Journals (Sweden)

    Rafael Nogueira Macedo

    2012-02-01

    Full Text Available This report focuses on a fatality involving severe dengue fever and melioidosis in a 28-year-old truck driver residing in Pacoti in northeastern Brazil. He exhibited long-term respiratory symptoms (48 days and went through a wide-ranging clinical investigation at three hospitals, after initial clinical diagnoses of pneumonia, visceral leishmaniasis, tuberculosis, and fungal sepsis. After death, Burkholderia pseudomallei was isolated in a culture of ascitic fluid. Dengue virus type 1 was detected by polymerase chain reaction in cerebrospinal fluid (CSF; this infection was the cause of death. This description reinforces the need to consider melioidosis among the reported differential diagnoses of community-acquired infections where both melioidosis and dengue fever are endemic.

  9. SOURCES OF POLLUTION AS A HAZARD FOR RIVER ENVIRONMENT IN CASE OF FLOOD

    Directory of Open Access Journals (Sweden)

    M. ZELENAKOVA

    2016-03-01

    Full Text Available In the case of flood the main damages on the environment may occur as a consequence of accidents at sources of pollution. The issue of pollution sources is a key area of environmental protection. While pollution from point sources can be disposed by suitable technology, for diffuse pollution are essential proposals of preventive measures, that creating conditions to prevent contamination. The paper presents results of evaluation the sources of pollution in Hornad river basin in the eastern Slovakia in flooded area. Environmental risk assessment methods can be particularly useful in evaluating whether uses are threatened when a stressor of concern is not expressed as a numeric criterion in water quality standards. The risk assessment framework can add value to watershed-based management.

  10. The relationship between Urbanisation and changes in flood regimes: the British case.

    Science.gov (United States)

    Prosdocimi, Ilaria; Miller, James; Kjeldsen, Thomas

    2013-04-01

    This pilot study investigates if long-term changes in observed series of extreme flood events can be attributed to changes in climate and land-use drivers. We investigate, in particular, changes of winter and summer peaks extracted from gauged instantaneous flows records in selected British catchments. Using a Poisson processes framework, the frequency and magnitude of extreme events above a threshold can be modelled simultaneously under the standard stationarity assumptions of constant location and scale. In the case of a non-stationary process, the framework was extended to include covariates to account for changes in the process parameters. By including covariates related to the physical process, such as increased urbanization or North Atlantic Oscillation (NAO) Index levels, rather than just time, an enhanced understanding of the changes in high flows is obtainable. Indeed some variability is expected in any natural process and can be partially explained by large scale measures like NAO Index. The focus of this study is to understand, once natural variability is taken into account, how much of the remaining variability can be explained by increased urbanization levels. For this study, catchments are selected that have experienced significant growth in urbanisation in the past decades, typically 1960s to present, and for which concurrent good quality high flow data are available. Temporal change in the urban extent within catchments is obtained using novel processing of historical mapping sources, whereby the urban, suburban and rural fractions are obtained for decadal periods. Suitable flow data from localised rural catchments are also included as control cases to compare observed changes in the flood regime of urbanised catchments against, and to provide evidence of changes in regional climate. Initial results suggest that the effect of urbanisation can be detected in the rate of occurrence of flood events, especially in summer, whereas the impact on flood

  11. Flood modeling using WMS model for determining peak flood discharge in southwest Iran case study: Simili basin in Khuzestan Province

    Science.gov (United States)

    Hoseini, Yaser; Azari, Arash; Pilpayeh, Alireza

    2016-10-01

    It is of high importance to determine the flood discharge of different basins, in studies on water resources. However, it is necessary to use new models to determine flood hydrograph parameters. Therefore, it will be beneficial to conduct studies to calibrate the models, keeping in mind the local conditions of different regions. Therefore, this study was carried out to determine the peak flood discharge of a basin located in Southwest Iran, using the TR-20, TR55, and HEC-1 methods of the WMS model (watershed modeling system). The obtained results were compared with empirical values, as well as those of the soil conservation service (SCS) approach. Based on the results obtained, the TR55 method of the WMS model recorded the highest agreement with empirical values in Southwest Iran.

  12. Study on effectiveness of flood control based on risk level: case study of Kampung Melayu Village and Bukit Duri Village

    Directory of Open Access Journals (Sweden)

    Farid Mohammad

    2017-01-01

    Full Text Available Jakarta, the capital city of Indonesia, experiences flood which causes activities disruption and losses almost every year. Many studies have been done to mitigate the impact of flooding. Most of them focus on reducing the inundated area as an indicator of the effectiveness of flood control. This study aims to evaluate the effectiveness of several flood control alternatives based on risk level reduction. The case study is located in Kampung Melayu Village and Bukit Duri Village which are densely populated with several economic area and almost every year experiencing severe flooding in Jakarta. Risk level analysis was carried out by the method based on guidelines issued by the Head of National Disaster Management Agency (BNPB No. 2/2012 with few modifications. The analysis is conducted on five alternatives of flood control which are diversion channel to East Flood Canal (KBT, diversion channel to the West Flood Canal (KBB in Pasar Minggu, river improvement, capacity enhancement on all components, and capacity enhancement focusing on one component. From the results, it is showed that enhancing capacity which focus on preparedness component by two levels are the best in terms of investment value to risk level reduction.

  13. Deriving Design Flood Hydrograph Based on Conditional Distribution: A Case Study of Danjiangkou Reservoir in Hanjiang Basin

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    Changjiang Xu

    2016-01-01

    Full Text Available Design flood hydrograph (DFH for a dam is the flood of suitable probability and magnitude adopted to ensure safety of the dam in accordance with appropriate design standards. Estimated quantiles of peak discharge and flood volumes are necessary for deriving the DFH, which are mutually correlated and need to be described by multivariate analysis methods. The joint probability distributions of peak discharge and flood volumes were established using copula functions. Then the general formulae of conditional most likely composition (CMLC and conditional expectation composition (CEC methods that consider the inherent relationship between flood peak and volumes were derived for estimating DFH. The Danjiangkou reservoir in Hanjiang basin was selected as a case study. The design values of flood volumes and 90% confidence intervals with different peak discharges were estimated by the proposed methods. The performance of CMLC and CEC methods was also compared with conventional flood frequency analysis, and the results show that CMLC method performs best for both bivariate and trivariate distributions which has the smallest relative error and root mean square error. The proposed CMLC method has strong statistical basis with unique design flood composition scheme and provides an alternative way for deriving DFH.

  14. Flooding, flood risks and coping strategies in urban informal residential areas: The case of Keko Machungwa, Dar es Salaam, Tanzania

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    Tumpale Sakijege

    2012-06-01

    Full Text Available This article presents findings from a study carried out in Keko Machungwa informal settlement in Dar es Salaam under the auspices of the Disaster Management Training Centre of Ardhi University, Tanzania. The settlement has experienced frequent flooding in the past five years, and this study explores the causes, risks, extent of flooding and coping strategies of residents as well as municipality and city officials. Key methods employed in capturing empirical evidence included mapping of zones by severity of flooding, interviews with households, sub-ward leaders, and municipal and city officials. Non-participant observation, primarily taking photographs, complemented these methods. Laboratory tests of water samples taken from shallow wells in the settlement were performed to establish the level of pollution. In addition, records of prevalence of water-borne diseases were gathered from a dispensary within the settlement to corroborate flooding events, water pollution and occurrence of such diseases. Findings show that flooding is contributed to by the lack of a coordinated stormwater drainage system; haphazard housing development within the valley; and blocking of the water stream by haphazard dumping of solid waste and construction. Risks associated with flooding include water and air pollution, diseases, waterlogging and blocked accessibility. The most common coping strategies at household level are use of sandbags and tree logs; raised pit latrines and doorsteps; provision of water outlet pipes above plinth level; construction of embankments, protection walls and elevation of house foundations; seasonal displacement; and boiling and chemical treatment of water. Recommendations for future action at household, community and city level are made.

  15. Flooding and Flood Management

    Science.gov (United States)

    Brooks, K.N.; Fallon, J.D.; Lorenz, D.L.; Stark, J.R.; Menard, Jason; Easter, K.W.; Perry, Jim

    2011-01-01

    Floods result in great human disasters globally and nationally, causing an average of $4 billion of damages each year in the United States. Minnesota has its share of floods and flood damages, and the state has awarded nearly $278 million to local units of government for flood mitigation projects through its Flood Hazard Mitigation Grant Program. Since 1995, flood mitigation in the Red River Valley has exceeded $146 million. Considerable local and state funding has been provided to manage and mitigate problems of excess stormwater in urban areas, flooding of farmlands, and flood damages at road crossings. The cumulative costs involved with floods and flood mitigation in Minnesota are not known precisely, but it is safe to conclude that flood mitigation is a costly business. This chapter begins with a description of floods in Minneosta to provide examples and contrasts across the state. Background material is presented to provide a basic understanding of floods and flood processes, predication, and management and mitigation. Methods of analyzing and characterizing floods are presented because they affect how we respond to flooding and can influence relevant practices. The understanding and perceptions of floods and flooding commonly differ among those who work in flood forecasting, flood protection, or water resource mamnagement and citizens and businesses affected by floods. These differences can become magnified following a major flood, pointing to the need for better understanding of flooding as well as common language to describe flood risks and the uncertainty associated with determining such risks. Expectations of accurate and timely flood forecasts and our ability to control floods do not always match reality. Striving for clarity is important in formulating policies that can help avoid recurring flood damages and costs.

  16. Hydraulic modelling for flood mapping and prevention: the case study of Cerfone River

    Science.gov (United States)

    Di Francesco, Silvia; Venturi, Sara; Manciola, Piergiorgio

    2016-04-01

    The research focuses on the hydraulic risk evaluation and danger estimation for different extreme flood events, in order to correctly implement mitigation measures in an anthropized basin. The Cerfone River (Tuscany, Italy), due to the several floods that have affected the neighbouring villages in recent years, is selected as case of study. A finite volume numerical model that solves the shallow water equations all over the computational domain, was used to simulate the unsteady evolution of the maximum extent of flooded areas for different scenarios. The one - dimensional approach (still widespread in engineering projects) can be inaccurate in complex flows, which are often two or three dimensional and sometimes does not manage to capture the flood spatial extents in terms of flow depth and velocity. The use of a two-dimensional numerical model seems to be the suitable instrument in terms of computational efficiency and adequacy of results. In fact it overcomes the limits of a one-dimensional modeling in terms of prediction of hydraulic variables with a less computational effort respect to a full 3d model. An accurate modeling of the river basin leads to the evaluation of the present hydraulic risk. Structural and non- structural measures are then studied, simulated and compared in order to define the optimal risk reduction plan for the area of study. At this aim, different flooding scenarios were simulated through the 2D mathematical model: i) existing state of the river and floodplain areas; ii) design of a levee to protect the most vulnerable populated areas against the flooding risk; iii) use of off - stream detention basins that strongly amplify the lamination capacity of floodplains. All these scenarios were simulated for different return periods: 50, 100, 200 and 500 years. The inputs of the hydraulic models are obtained in accordance with the legislative requirement of Tuscany Region; in particular discharge hydrographs are evaluate through the ALTo

  17. The uncertainty cascade in flood risk assessment under changing climatic conditions - the Biala Tarnowska case study

    Science.gov (United States)

    Doroszkiewicz, Joanna; Romanowicz, Renata

    2016-04-01

    Uncertainty in the results of the hydraulic model is not only associated with the limitations of that model and the shortcomings of data. An important factor that has a major impact on the uncertainty of the flood risk assessment in a changing climate conditions is associated with the uncertainty of future climate scenarios (IPCC WG I, 2013). Future climate projections provided by global climate models are used to generate future runoff required as an input to hydraulic models applied in the derivation of flood risk maps. Biala Tarnowska catchment, situated in southern Poland is used as a case study. Future discharges at the input to a hydraulic model are obtained using the HBV model and climate projections obtained from the EUROCORDEX project. The study describes a cascade of uncertainty related to different stages of the process of derivation of flood risk maps under changing climate conditions. In this context it takes into account the uncertainty of future climate projections, an uncertainty of flow routing model, the propagation of that uncertainty through the hydraulic model, and finally, the uncertainty related to the derivation of flood risk maps. One of the aims of this study is an assessment of a relative impact of different sources of uncertainty on the uncertainty of flood risk maps. Due to the complexity of the process, an assessment of total uncertainty of maps of inundation probability might be very computer time consuming. As a way forward we present an application of a hydraulic model simulator based on a nonlinear transfer function model for the chosen locations along the river reach. The transfer function model parameters are estimated based on the simulations of the hydraulic model at each of the model cross-section. The study shows that the application of the simulator substantially reduces the computer requirements related to the derivation of flood risk maps under future climatic conditions. Acknowledgements: This work was supported by the

  18. Decadal flood frequency analyses: Case study of station Litija on the Sava river

    Science.gov (United States)

    Bezak, Nejc; Brilly, Mitja; Sraj, Mojca

    2013-04-01

    The objective of the study was (1) to perform decadal flood frequency analyses for the nine 30 years long data series, (2) to compare some commonly used distribution functions, (3) to compare the method of moments and the method of L-moments, and (4) to evaluate changes in the Q-T curves for the different hydrological periods. Decadal flood frequency analyses can be useful in climate changes or climate variability assessment. Investigation of the influence of the selected period for flood frequency analyses is important for the observation of changes in the discharge data. To reach the optimal flood frequency analyses results one should choose the best fitting distribution function and appropriate parameter estimation technique. The hydrological station Litija on the river Sava is one of the oldest gauging stations in Slovenia. 116 years of the daily discharge data were used for decadal flood frequency analyses. Data was separated in nine parts, each part contained 30 years of annual maximums. The normal, log-normal, Pearson 3, log-Pearson 3, Gumbel, generalized extreme value (GEV) and generalized logistic (GL) distributions were used for flood frequency analyses. The method of moments and the method of L-moments were used for parameters estimation. The root mean square error (RMSE), mean absolute error (MAE), Probability plot correlation coefficient (PPCC), Kolmogorov-Smirnov (K-S), Anderson-Darling (A-D) and AIC (Akaike information criterion) tests were used to compare distribution functions and different data samples. The L-moments ratio diagram was also used to assess differences between distribution functions. The GEV, Pearson 3 and log-Pearson 3 distributions gave better results as the normal, log-normal, Gumbel and GL distributions. The Gumbel and log-normal distributions had larger dispersion of tests results as other considered distributions. When distribution parameters were estimated with the method of L-moments test results were better as in case of the

  19. Flash floods in the Sahara: a case study for the 28 January 2013 flood in Qena, Egypt

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    Moawad Badawy Moawad

    2016-01-01

    Full Text Available Understanding the torrential rainfall and its consequent surface runoff in the Sahara is a crucial issue for better flood protection and water management plans. This is often hampered by the lack of appropriate in situ measurements. Even now the satellite-derived rainfall suffers from great uncertainty. Thus, we adjusted the data obtained from real-time satellite rainfall coverage (HYDIS using the in situ observed rainfall (Robs. Hydro-morphological parameters were then integrated with the empirical curve number (CN approach to estimate the surface runoff in Qena, Egypt during the 28 January 2013 flash flood event. We deduced that the study area received a total precipitation (∑Rcum of ∼35.6 × 106 [mm] and a total rain volume (∑Rvol of ∼88.9 × 109 [m3] mainly from wadi Qena (89.8%. The majority of the rainfalls fell at light intensity (<2.5 [mm hr−1]. The estimated total surface runoff (∑Qsur was 26.5 × 106 mm and the total runoff volume (∑Qvol was 66.2 × 106 [m3]. The total surface transmission losses (∑Tlos were calculated as 9.1 × 106 [mm], which represents about 25.6% of the total precipitation (∑Rcum and creates substantial opportunities for alluvial aquifer recharge. The total surface runoff (∑Qsur and flood magnitude were generally low, therefore, flood influences were restricted to the destruction of some roads in Qena but no fatalities were involved, nevertheless. Most of the running water was contained by El Sail Canal and poured into the Nile River. It is expected that the applied method in this study will be helpful for our understanding and quantification of flood hydrology and contribute to better risk management plan in the arid and hyper-arid regions.

  20. A strategy-based framework for assessing the flood resilience of cities : a Hamburg case study

    NARCIS (Netherlands)

    Restemeyer, Britta; Woltjer, Johannes; van den Brink, Margaretha

    2015-01-01

    Climate change and continuous urbanization contribute to an increased urban vulnerability towards flooding. Only relying on traditional flood control measures is recognized as inadequate, since the damage can be catastrophic if flood controls fail. The idea of a flood-resilient city – one which can

  1. Multiple Scedosporium apiospermum abscesses in a woman survivor of a tsunami in northeastern Japan: a case report

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    Nakamura Yutaka

    2011-10-01

    Full Text Available Abstract Introduction Scedosporium apiospermum is increasingly recognized as a cause of localized and disseminated mycotic infections in near-drowning victims. Case presentation We report the case of a 59-year-old Japanese woman who was a survivor of a tsunami in northeastern Japan and who had lung and brain abscesses caused by S. apiospermum. Initially, an aspergillus infection was suspected, so she was treated with micafungin. However, computed tomography scans of her chest revealed lung abscesses, and magnetic resonance images demonstrated multiple abscesses in her brain. S. apiospermum was cultured from her bronchoalveolar lavage fluid, and antimycotic therapy with voriconazole was initiated. Since she developed an increase in the frequency of premature ventricular contractions, an adverse drug reaction to the voriconazole was suspected. She was started on a treatment of a combination of low-dose voriconazole and liposomal amphotericin B. After combination therapy, further computed tomography scans of the chest and magnetic resonance images of her brain showed a demarcation of abscesses. Conclusions Voriconazole appeared to have a successful record in treating scedosporiosis after a near drowning but, owing to several adverse effects, may possibly not be recommended. Thus, a combination treatment of low-dose voriconazole and liposomal amphotericin B may be a safe and effective treatment for an S. apiospermum infection. Even though a diagnosis of scedosporiosis may be difficult, a fast and correct etiological diagnosis could improve the patient's chance of recovery in any case.

  2. Remote Sensing and Geographic Information Systems (GIS Contribution to the Inventory of Infrastructure Susceptible to Earthquake and Flooding Hazards in North-Eastern Greece

    Directory of Open Access Journals (Sweden)

    Ioanna Papadopoulou

    2012-09-01

    Full Text Available For civil protection reasons there is a strong need to improve the inventory of areas that are more vulnerable to earthquake ground motions or to earthquake-related secondary effects, such as landslides, liquefaction or soil amplifications. The use of remote sensing and Geographic Information Systems (GIS methods along with the related geo-databases can assist local and national authorities to be better prepared and organized. Remote sensing and GIS techniques are investigated in north-eastern Greece in order to contribute to the systematic, standardized inventory of those areas that are more susceptible to earthquake ground motions, to earthquake-related secondary effects and to tsunami-waves. Knowing areas with aggregated occurrence of causal (“negative” factors influencing earthquake shock and, thus, the damage intensity, this knowledge can be integrated into disaster preparedness and mitigation measurements. The evaluation of satellite imageries, digital topographic data and open source geodata contributes to the acquisition of the specific tectonic, geologic and geomorphologic settings influencing local site conditions in an area and, thus, estimate possible damage to be suffered.

  3. Exploring adaptation pathways in terms of flood risk management at a city scale – a case study for Shanghai city

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    Ke Qian

    2016-01-01

    Full Text Available Cities are vulnerable to flooding and historical events, for instance Hurricane Sandy in 2012, have showed that losses in the cities are costly. In the context of climate change and socio-economic development, future flood risk will inevitably rise; adaptive measures, for instance upgrading of sea dikes and floodwalls, improving drainage systems and implementing green infrastructures, are proposed under the changing environment in the cities. A question of when to implement what measures in the cities over time is then brought up. The approach of dynamic adaptive policy pathways is applied to formulate adaptation pathways for a case study of Shanghai to explore the optimal investment strategy in context of deep uncertainties. Adaptation concept is not only aiming to achieve optimal strategy but also to determine when to implement the measures. The adaptation pathways for three types of floods (coastal flood, river flood and pluvial flood in Shanghai were formulated through a preliminary qualitative analysis. This could provide an insight to the long-term feasibility of adaptive flood risk strategies. This research could provide a rational indication for policy/decision makers on future adaptation strategy at the city scale.

  4. Association between flood and the morbidity of bacillary dysentery in Zibo City, China: a symmetric bidirectional case-crossover study.

    Science.gov (United States)

    Zhang, Feifei; Ding, Guoyong; Liu, Zhidong; Zhang, Caixia; Jiang, Baofa

    2016-12-01

    This study examined the relationship between daily morbidity of bacillary dysentery and flood in 2007 in Zibo City, China, using a symmetric bidirectional case-crossover study. Odds ratios (ORs) and 95 % confidence intervals (CIs) on the basis of multivariate model and stratified analysis at different lagged days were calculated to estimate the risk of flood on bacillary dysentery. A total of 902 notified bacillary dysentery cases were identified during the study period. The median of case distribution was 7-year-old and biased to children. Multivariable analysis showed that flood was associated with an increased risk of bacillary dysentery, with the largest OR of 1.849 (95 % CI 1.229-2.780) at 2-day lag. Gender-specific analysis showed that there was a significant association between flood and bacillary dysentery among males only (ORs >1 from lag 1 to lag 5), with the strongest lagged effect at 2-day lag (OR = 2.820, 95 % CI 1.629-4.881), and the result of age-specific indicated that youngsters had a slightly larger risk to develop flood-related bacillary dysentery than older people at one shorter lagged day (OR = 2.000, 95 % CI 1.128-3.546 in youngsters at lag 2; OR = 1.879, 95 % CI 1.069-3.305 in older people at lag 3). Our study has confirmed that there is a positive association between flood and the risk of bacillary dysentery in selected study area. Males and youngsters may be the vulnerable and high-risk populations to develop the flood-related bacillary dysentery. Results from this study will provide recommendations to make available strategies for government to deal with negative health outcomes due to floods.

  5. Association between flood and the morbidity of bacillary dysentery in Zibo City, China: a symmetric bidirectional case-crossover study

    Science.gov (United States)

    Zhang, Feifei; Ding, Guoyong; Liu, Zhidong; Zhang, Caixia; Jiang, Baofa

    2016-12-01

    This study examined the relationship between daily morbidity of bacillary dysentery and flood in 2007 in Zibo City, China, using a symmetric bidirectional case-crossover study. Odds ratios (ORs) and 95 % confidence intervals (CIs) on the basis of multivariate model and stratified analysis at different lagged days were calculated to estimate the risk of flood on bacillary dysentery. A total of 902 notified bacillary dysentery cases were identified during the study period. The median of case distribution was 7-year-old and biased to children. Multivariable analysis showed that flood was associated with an increased risk of bacillary dysentery, with the largest OR of 1.849 (95 % CI 1.229-2.780) at 2-day lag. Gender-specific analysis showed that there was a significant association between flood and bacillary dysentery among males only (ORs >1 from lag 1 to lag 5), with the strongest lagged effect at 2-day lag (OR = 2.820, 95 % CI 1.629-4.881), and the result of age-specific indicated that youngsters had a slightly larger risk to develop flood-related bacillary dysentery than older people at one shorter lagged day (OR = 2.000, 95 % CI 1.128-3.546 in youngsters at lag 2; OR = 1.879, 95 % CI 1.069-3.305 in older people at lag 3). Our study has confirmed that there is a positive association between flood and the risk of bacillary dysentery in selected study area. Males and youngsters may be the vulnerable and high-risk populations to develop the flood-related bacillary dysentery. Results from this study will provide recommendations to make available strategies for government to deal with negative health outcomes due to floods.

  6. Relations between rainfall and triggering of debris-flow: case study of Cancia (Dolomites, Northeastern Italy

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    M. Bacchini

    2003-01-01

    Full Text Available Debris-flows occurring in the area of Cancia (Dolomites, Northeastern Italy in recent years have exposed the population to serious risk. In response to the recurring hazard, an alarm and monitoring system was installed to provide a sufficient level of safeguard for inhabitants and infrastructures. The data recorded at three rain gauges during debris-flow events has been analysed, taking into consideration the different elevation of the gauges to delineate the storm rainfall distributions. Rainfall data is compared with the occurrence of debris-flows to examine relations between debris-flow initiation and rainfall. In addition, the data is compared with that recorded during debris-flows which occurred under similar or different geological settings in the Eastern Italian Alps, in order to define triggering thresholds. A threshold for debris-flow activity in terms of mean intensity, duration and mean annual precipitation (M.A.P. is defined for the study area The normalised rainfall and the normalised intensity are expressed as a per cent with respect to M.A.P. This threshold is compared with thresholds proposed by other authors, and the comparison shows that a lower value is obtained, indicating the debris-flow susceptibility of the area. The threshold equations are:  R/M.A.P. = - 1.36 · ln(I + 3.93  where I > 2 mm/h  I /M.A.P. = 0.74 · D-0.56.  The determination of a debris-flow threshold is linked to the necessity of a fast decisional phase in a warning system for debris-flow protection. This threshold cannot be used as a predictive tool, but rather as a warning signal for technicians who manage the monitoring/warning system.

  7. Spatial Profile of Poverty.Case Study:The North-Eastern Development Region in Romania

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    Andrei SCHVAB

    2015-06-01

    Full Text Available In the present study the authors try to em-phasize the interdependent relations that are established between space and poverty, as well as the modalities through which poverty policies can be optimized and implemented at the territo-rial systems level in accordance to the polycen-tric development model.The f rst goal of the study is to understand the way in which the complexity of the territory, in its structure and relations, inf uences in un-equal ways the territorial pattern of poverty and development. The concept of territorial poverty that we use in the present study transcends the usual connotation of poverty as a simple lack of different kind of resources towards the incapacity of the system to offer a wide range of impulses and solutions to the encountered problems and thus induce a state of underdevelopment.The second goal is to understand in which ways the polycentric development theory can play a role in reducing poverty. In this sense the authors created a poverty index, and based on this index a polycentric development model was created for the North-Eastern region. This poly-centric development model has direct implica-tions for policy makers, as it highlights the areas that require the most attention and the develop-ment pole that should inf uence its development. By taking into consideration the results of this study, the next logical step for policy makers is to implement the necessary measures by consider-ing the relations between the development pole and the underdeveloped area that is under its in-f uence area. In this respect tailor-f t policies and measures can be applied in the effort to reduce poverty levels.

  8. Damages caused by floods and flash-floods upon critical infrastructures. Case study: Maramureş county (Romania

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    Eugen Nour

    2011-08-01

    Full Text Available Critical infrastructure is defined as a network including telecommunications, informationservices, energy transport (electrical lines, natural gas and oil pipes, water supply, goods and personstransportation, financial, banking and emergency response services. All these are so significant that adisequilibrium or interruption of their operation would have a disturbing effect upon the daily life.Estimating the damage done by natural hazards to certain critical infrastructure sectors is considered animportant interest topic. The main purpose of this research is the estimation of the damages generatedby floods and flash-floods on the critical infrastructure in Maramureş County during 2005-2010. Thedamages analysis is based mainly on observations and quantitative data, obtained after a thoroughanalysis of literature and reports from the Ministry of Environment and Forests and the Inspectorate forEmergency Situation of Maramureş County. The results of the study were alarming. The damages causedby floods during the period subjected to study reach approximately 32 million dollars, highlighting theneed for an integrated management system for critical infrastructure protection.

  9. Simplification approach to detect urban areas vulnerable to flash floods using GIS: a case study Warsaw

    Science.gov (United States)

    Wicht, Marzena; Osińska-Skotak, Katarzyna

    2016-04-01

    The aim of this study is to develop a consistent methodology to determine urban areas that are particularly vulnerable to the effects of torrential rains. They are, as a result of climate change, more and more prevalent in the temperate climate, usually spring - summer from mid-May to late August - and involve the risk of flash floods. In recent years, the increase in the incidence of such phenomena is noticeable throughout the whole Europe. It is assumed that through the analysis of environmental and infrastructural conditions, using the developed methodology, it is possible to determine areas vulnerable to flooding due to torrential rains. This may lead to a better management, quicker response in case of a phenomenon, and even to take measures to prevent the occurrence of adverse effects of torrential rains (for instance modernization of the urban drainage system and development of methods to get rid of rapidly collected water). Designation of areas particularly vulnerable to the effects of heavy rains can be achieved by adapting hydrological models, but they require an appropriate adjustment and highly accurate input data: (based on spot or radar measurements of precipitation, land cover, soil type, humidity, wind speed, vegetation species in a given area, growing season, the roughness and porosity of the cover and soil moisture) but such detailed data are generally hard to obtain or not available for less developed areas. It could also be achieved by performing spatial analysis in GIS, which is a more simplified form of modelling, but it gives results more quickly and the methodology can be adapted to the commonly available data. A case study of Warsaw's district Powiśle has been undertaken for three epochs - from 2008 to 2010 and areas, that are particularly vulnerable to the effects of flash floods and heavy rains, have been designated.

  10. Driver Sleepiness and Risk of Car Crashes in Shenyang, a Chinese Northeastern City: Population-based Case-control Study

    Institute of Scientific and Technical Information of China (English)

    GAI-FEN LIU; SONG HAN; DUO-HONG LIANG; FENG-ZHI WANG; XIN-ZHU SHI; JIAN YU; ZHENG-LAI WU

    2003-01-01

    To estimate the association of driver sleepiness with the risk of car crashes.Methods A population-based case-control study was conducted in Shenyang, a northeastern city in China, between November 2001 and July 2002. The case group comprised 406 car drivers involved in crashes, and 438 car drivers recruited at randomly selected sites, and on the day of week, and the time of day when they were driving on highways in the study region during the study period were used as control groups. Face-to-face interviews with drivers were conducted according to a well-structured questionnaire covering the circumstances of their current trip and their background information.Stanford sleepiness scale and Epworth sleepiness scale were used to quantify acute sleepiness and chronic sleepiness respectively. Results There was a strong association between chronic sleepiness and the risk of car crash. Significantly increased risk of crash was associated with drivers who identified themselves as sleepy (Epworth sleepiness score ≥ 10 vs <10; adjusted odds ratio 2.07, 95%confidence interval 1.30 to 3.29), but no increased risk was associated with measures of acute sleepiness. Conclusions Chronic sleepiness in car drivers significantly increases the risk of car crash. Reductions in road traffic injuries may be achieved if fewer people drive when they are sleepy.

  11. Flood resilience in the context of shifting patterns of risk, complexity and governance: An exploratory case study

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    Johnson Noel

    2016-01-01

    Full Text Available This paper presents a case study of an industrial locale in the United Kingdom which has come together in an innovative governance structure to respond to the risk of flooding. Public and private sector bodies have joined together to establish a ‘business improvement district’ (BID, the sole purpose of which is to build resilience to future flooding events. More specifically, we examine the effectiveness of this strategy as a mechanism for capacity building within the small and medium sized enterprise sector. This is an important area of study as small and medium sized enterprises (SMEs are particularly vulnerable to the negative impacts of a flood event, as they possess fewer resources than their larger counterparts leaving them with less capacity and organisational slack to respond to a major disruption. Drawing upon primary and secondary data, we identify both institutional barriers and enablers to the development of novel responses to flooding.

  12. The impact of flooding on people living with HIV: a case study from the Ohangwena Region, Namibia.

    Science.gov (United States)

    Anthonj, Carmen; Nkongolo, Odon T; Schmitz, Peter; Hango, Johannes N; Kistemann, Thomas

    2015-01-01

    can be transferred to any flood-affected region that has a high HIV prevalence and relies mainly on subsistence agriculture. They serve as a model case for analysing vulnerabilities related to health and health service provision under disaster conditions. The impact will vary according to the physical, geographical, climatological, social, and behavioural characteristics of the region and the people affected. In the Ohangwena region, a disaster risk management mechanism is already in place which addresses people with HIV during flooding. However, preparedness could be improved further by applying the HIV and Flooding Framework.

  13. The impact of flooding on people living with HIV: a case study from the Ohangwena Region, Namibia

    Directory of Open Access Journals (Sweden)

    Carmen Anthonj

    2015-03-01

    the HIV and Flooding Framework are not specific to Ohangwena and can be transferred to any flood-affected region that has a high HIV prevalence and relies mainly on subsistence agriculture. They serve as a model case for analysing vulnerabilities related to health and health service provision under disaster conditions. The impact will vary according to the physical, geographical, climatological, social, and behavioural characteristics of the region and the people affected. In the Ohangwena region, a disaster risk management mechanism is already in place which addresses people with HIV during flooding. However, preparedness could be improved further by applying the HIV and Flooding Framework.

  14. Prescriptions for adaptive comanagement: the case of flood management in the German Rhine basin

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    Gert Becker

    2015-09-01

    Full Text Available Centrally administered bureaucracies are ill suited to managing the environmental resources of complex social-ecological systems. Therefore management approaches are required that can better deal with its complexity and uncertainty, which are further exacerbated by developments such as climate change. Adaptive comanagement (ACM has emerged as a relatively novel governance approach and potential solution to the challenges arising. Adaptive comanagement hinges on certain institutional prescriptions intended to enhance the adaptability of management by improving the comprehension of and response to the complex context and surprises of social-ecological systems. The ACM literature describes that for enhanced adaptability, institutional arrangements should be polycentric, aligned with the scale of ecosystems (the bioregional approach, feature open and participatory governance, and involve much experimentation. The case of flood management in the German part of the Rhine basin is used to provide an assessment of these ideas. We analyze whether and to what degree the prescriptions have been implemented and whether or not certain fundamental changes seen in German flood management can be traced back to the application of the prescriptions. Our study demonstrates a transition from the traditional engineering and "flood control" approach to a more holistic management concept based on a risk perspective. In this process, the four ACM prescriptions have made an important contribution in preparing or facilitating policy changes. The findings suggest that the application of the prescriptions requires the right supporting context before they can be applied to the fullest extent possible, such as a high problem pressure, new discourses, or leading actors. A major constraint arises in the misalignment of political power and of the different interests of the actors, which contribute to reactive management and inadequate interplay. To address this, we recommend

  15. Water supply management using an extended group fuzzy decision-making method: a case study in north-eastern Iran

    Science.gov (United States)

    Minatour, Yasser; Bonakdari, Hossein; Zarghami, Mahdi; Bakhshi, Maryam Ali

    2015-09-01

    The purpose of this study was to develop a group fuzzy multi-criteria decision-making method to be applied in rating problems associated with water resources management. Thus, here Chen's group fuzzy TOPSIS method extended by a difference technique to handle uncertainties of applying a group decision making. Then, the extended group fuzzy TOPSIS method combined with a consistency check. In the presented method, initially linguistic judgments are being surveyed via a consistency checking process, and afterward these judgments are being used in the extended Chen's fuzzy TOPSIS method. Here, each expert's opinion is turned to accurate mathematical numbers and, then, to apply uncertainties, the opinions of group are turned to fuzzy numbers using three mathematical operators. The proposed method is applied to select the optimal strategy for the rural water supply of Nohoor village in north-eastern Iran, as a case study and illustrated example. Sensitivity analyses test over results and comparing results with project reality showed that proposed method offered good results for water resources projects.

  16. An Ecological Flood Control System in Phoenix Island of Huzhou, China: A Case Study

    OpenAIRE

    Zhuowen Wang; Jun Liu; Cheng Gao

    2013-01-01

    Traditional flood control systems always have a conflict with natural ones, i.e., rivers in cities are usually straight and smooth, whereas natural ones are according to ecological mechanisms. Social and economic developments in the modern world require a new system combining ecological needs and traditional flood control system. Ecological flood control systems were put forward and defined as flood control systems with full consideration of ecological demands for sustainable development. In ...

  17. Effective Integration of Earth Observation Data and Flood Modeling for Rapid Disaster Response: The Texas 2015 Case

    Science.gov (United States)

    Schumann, G.

    2016-12-01

    Routinely obtaining real-time 2-D inundation patterns of a flood event at a meaningful spatial resolution and over large scales is at the moment only feasible with either operational aircraft flights or satellite imagery. Of course having model simulations of floodplain inundation available to complement the remote sensing data is highly desirable, for both event re-analysis and forecasting event inundation. Using the Texas 2015 flood disaster, we demonstrate the value of multi-scale EO data for large scale 2-D floodplain inundation modeling and forecasting. A dynamic re-analysis of the Texas 2015 flood disaster was run using a 2-D flood model developed for accurate large scale simulations. We simulated the major rivers entering the Gulf of Mexico and used flood maps produced from both optical and SAR satellite imagery to examine regional model sensitivities and assess associated performance. It was demonstrated that satellite flood maps can complement model simulations and add value, although this is largely dependent on a number of important factors, such as image availability, regional landscape topology, and model uncertainty. In the preferred case where model uncertainty is high, landscape topology is complex (i.e. urbanized coastal area) and satellite flood maps are available (in case of SAR for instance), satellite data can significantly reduce model uncertainty by identifying the "best possible" model parameter set. However, most often the situation is occurring where model uncertainty is low and spatially contiguous flooding can be mapped from satellites easily enough, such as in rural large inland river floodplains. Consequently, not much value from satellites can be added. Nevertheless, where a large number of flood maps are available, model credibility can be increased substantially. In the case presented here this was true for at least 60% of the many thousands of kilometers of river flow length simulated, where satellite flood maps existed. The next

  18. Governance in support of integrated flood risk management? The case of Romania

    NARCIS (Netherlands)

    Vinke-de Kruijf, Joanne; Kuks, Stefanus M.M.; Augustijn, Dionysius C.M.

    2015-01-01

    Building on an existing model of governance, this paper aims to assess the supportiveness of Romania׳s structural flood risk governance context towards integrated flood risk management. We assert that a governance structure supports the development and implementation of integrated flood risk

  19. Modelling the benefits of flood emergency management measures in reducing damages: a case study on Sondrio, Italy

    Directory of Open Access Journals (Sweden)

    D. Molinari

    2013-08-01

    Full Text Available The European "Floods Directive" 2007/60/EU has produced an important shift from a traditional approach to flood risk management centred only on hazard analysis and forecast to a newer one which encompasses other aspects relevant to decision-making and which reflect recent research advances in both hydraulic engineering and social studies on disaster risk. This paper accordingly proposes a way of modelling the benefits of flood emergency management interventions calculating the possible damages by taking into account exposure, vulnerability, and expected damage reduction. The results of this model can be used to inform decisions and choices for the implementation of flood emergency management measures. A central role is played by expected damages, which are the direct and indirect consequence of the occurrence of floods in exposed and vulnerable urban systems. How damages should be defined and measured is a key question that this paper tries to address. The Floods Directive suggests that mitigation measures taken to reduce flood impact need to be evaluated also by means of a cost–benefit analysis. The paper presents a methodology for assessing the effectiveness of early warning for flash floods, considering its potential impact in reducing direct physical damage, and it assesses the general benefit in regard to other types of damages and losses compared with the emergency management costs. The methodology is applied to the case study area of the city of Sondrio in the northern Alpine region of Italy. A critical discussion follows the application. Its purpose is to highlight the strengths and weaknesses of available models for quantifying direct physical damage and of the general model proposed, given the current state of the art in damage and loss assessment.

  20. Modelling the benefits of flood emergency management measures in reducing damages: a case study on Sondrio, Italy

    Science.gov (United States)

    Molinari, D.; Ballio, F.; Menoni, S.

    2013-08-01

    The European "Floods Directive" 2007/60/EU has produced an important shift from a traditional approach to flood risk management centred only on hazard analysis and forecast to a newer one which encompasses other aspects relevant to decision-making and which reflect recent research advances in both hydraulic engineering and social studies on disaster risk. This paper accordingly proposes a way of modelling the benefits of flood emergency management interventions calculating the possible damages by taking into account exposure, vulnerability, and expected damage reduction. The results of this model can be used to inform decisions and choices for the implementation of flood emergency management measures. A central role is played by expected damages, which are the direct and indirect consequence of the occurrence of floods in exposed and vulnerable urban systems. How damages should be defined and measured is a key question that this paper tries to address. The Floods Directive suggests that mitigation measures taken to reduce flood impact need to be evaluated also by means of a cost-benefit analysis. The paper presents a methodology for assessing the effectiveness of early warning for flash floods, considering its potential impact in reducing direct physical damage, and it assesses the general benefit in regard to other types of damages and losses compared with the emergency management costs. The methodology is applied to the case study area of the city of Sondrio in the northern Alpine region of Italy. A critical discussion follows the application. Its purpose is to highlight the strengths and weaknesses of available models for quantifying direct physical damage and of the general model proposed, given the current state of the art in damage and loss assessment.

  1. Flood Hazard Mapping using Hydraulic Model and GIS: A Case Study in Mandalay City, Myanmar

    Directory of Open Access Journals (Sweden)

    Kyu Kyu Sein

    2016-01-01

    Full Text Available This paper presents the use of flood frequency analysis integrating with 1D Hydraulic model (HECRAS and Geographic Information System (GIS to prepare flood hazard maps of different return periods in Ayeyarwady River at Mandalay City in Myanmar. Gumbel’s distribution was used to calculate the flood peak of different return periods, namely, 10 years, 20 years, 50 years, and 100 years. The flood peak from frequency analysis were input into HEC-RAS model to find the corresponding flood level and extents in the study area. The model results were used in integrating with ArcGIS to generate flood plain maps. Flood depths and extents have been identified through flood plain maps. Analysis of 100 years return period flood plain map indicated that 157.88 km2 with the percentage of 17.54% is likely to be inundated. The predicted flood depth ranges varies from greater than 0 to 24 m in the flood plains and on the river. The range between 3 to 5 m were identified in the urban area of Chanayetharzan, Patheingyi, and Amarapua Townships. The highest inundated area was 85 km2 in the Amarapura Township.

  2. Flood risk assessment in The Netherlands: a case study for dike ring South Holland.

    Science.gov (United States)

    Jonkman, Sebastiaan N; Kok, Matthijs; Vrijling, Johannes K

    2008-10-01

    Large parts of The Netherlands are below sea level. Therefore, it is important to have insight into the possible consequences and risks of flooding. In this article, an analysis of the risks due to flooding of the dike ring area South Holland in The Netherlands is presented. For different flood scenarios the potential number of fatalities is estimated. Results indicate that a flood event in this area can expose large and densely populated areas and result in hundreds to thousands of fatalities. Evacuation of South Holland before a coastal flood will be difficult due to the large amount of time required for evacuation and the limited time available. By combination with available information regarding the probability of occurrence of different flood scenarios, the flood risks have been quantified. The probability of death for a person in South Holland due to flooding, the so-called individual risk, is small. The probability of a flood disaster with many fatalities, the so-called societal risk, is relatively large in comparison with the societal risks in other sectors in The Netherlands, such as the chemical sector and aviation. The societal risk of flooding appears to be unacceptable according to some of the existing risk limits that have been proposed in literature. These results indicate the necessity of a further societal discussion on the acceptable level of flood risk in The Netherlands and the need for additional risk reducing measures.

  3. Spatial Modeling of Flood Sea Tides (Case Study: East Coast Semarang

    Directory of Open Access Journals (Sweden)

    Muhammad Aris Marfai

    2004-01-01

    Full Text Available The aims of this research are 1 to construct a spatial model of tidal flood hazard, 2 to do hazard analysis of tidal flood. Spatial modelling has been generated using Geographic Information System (GIS software and ILWIS software was seleccted to do the model operation. Neighborhood function and digital elevation model (DEM have been applied on the modelling calculation process. DEM data was correted and menipulated using map calculation on the digital form. Tidal flood hazard analysis has been done by means of map calulation on the tidal flood hazard map and detail landuse map. Histogram and tabulation from the result of the map calculation have been analyzed to identify the impact of the tidal flood hazard on the landuse. The highest impact of the tidal flood hazard occurs on the 1 meter of tidal flood level, where in the inundation occurs mainly on the fishpond and yard/ open space area.

  4. Post-Flood Profile of Leptospirosis Cases at Teaching Hospital of Municipal Medical College in Surat City

    Directory of Open Access Journals (Sweden)

    Prasad Rachna, Srivastava Vipul, Bansal RK, Pawar AB, Desai Vandana, Desai Kalpana, Jain Mannu

    2010-06-01

    Full Text Available This study reports the clinical profile, pattern of organ involvement and the case fatality of 112 cases of Leptospirosis admitted during an outbreak in the post flood period from August to September 2006 in Surat city. The study reveals the necessity for early detection of cases in an epidemic situation, chemoprophylaxis of those exposed and prompt referral and management with excellent ICU support for decreasing the mortality associated with the disease.

  5. The Use of Geospatial Technologies in Flood Hazard Mapping and Assessment: Case Study from River Evros

    Science.gov (United States)

    Mentzafou, Angeliki; Markogianni, Vasiliki; Dimitriou, Elias

    2016-11-01

    Many scientists link climate change to the increase of the extreme weather phenomena frequency, which combined with land use changes often lead to disasters with severe social and economic effects. Especially floods as a consequence of heavy rainfall can put vulnerable human and natural systems such as transboundary wetlands at risk. In order to meet the European Directive 2007/60/EC requirements for the development of flood risk management plans, the flood hazard map of Evros transboundary watershed was produced after a grid-based GIS modelling method that aggregates the main factors related to the development of floods: topography, land use, geology, slope, flow accumulation and rainfall intensity. The verification of this tool was achieved through the comparison between the produced hazard map and the inundation maps derived from the supervised classification of Landsat 5 and 7 satellite imageries of four flood events that took place at Evros delta proximity, a wetland of international importance. The comparison of the modelled output (high and very high flood hazard areas) with the extent of the inundated areas as mapped from the satellite data indicated the satisfactory performance of the model. Furthermore, the vulnerability of each land use against the flood events was examined. Geographically Weighted Regression has also been applied between the final flood hazard map and the major factors in order to ascertain their contribution to flood events. The results accredited the existence of a strong relationship between land uses and flood hazard indicating the flood susceptibility of the lowlands and agricultural land. A dynamic transboundary flood hazard management plan should be developed in order to meet the Flood Directive requirements for adequate and coordinated mitigation practices to reduce flood risk.

  6. The Use of Geospatial Technologies in Flood Hazard Mapping and Assessment: Case Study from River Evros

    Science.gov (United States)

    Mentzafou, Angeliki; Markogianni, Vasiliki; Dimitriou, Elias

    2017-02-01

    Many scientists link climate change to the increase of the extreme weather phenomena frequency, which combined with land use changes often lead to disasters with severe social and economic effects. Especially floods as a consequence of heavy rainfall can put vulnerable human and natural systems such as transboundary wetlands at risk. In order to meet the European Directive 2007/60/EC requirements for the development of flood risk management plans, the flood hazard map of Evros transboundary watershed was produced after a grid-based GIS modelling method that aggregates the main factors related to the development of floods: topography, land use, geology, slope, flow accumulation and rainfall intensity. The verification of this tool was achieved through the comparison between the produced hazard map and the inundation maps derived from the supervised classification of Landsat 5 and 7 satellite imageries of four flood events that took place at Evros delta proximity, a wetland of international importance. The comparison of the modelled output (high and very high flood hazard areas) with the extent of the inundated areas as mapped from the satellite data indicated the satisfactory performance of the model. Furthermore, the vulnerability of each land use against the flood events was examined. Geographically Weighted Regression has also been applied between the final flood hazard map and the major factors in order to ascertain their contribution to flood events. The results accredited the existence of a strong relationship between land uses and flood hazard indicating the flood susceptibility of the lowlands and agricultural land. A dynamic transboundary flood hazard management plan should be developed in order to meet the Flood Directive requirements for adequate and coordinated mitigation practices to reduce flood risk.

  7. Bacillary angiomatosis in HIV-positive patient from Northeastern Brazil: a case report

    Directory of Open Access Journals (Sweden)

    Renata Félix da Justa

    2011-10-01

    Full Text Available It is a report of disseminated bacillary angiomatosis (BA in a 23-year-old female patient, who is HIV-positive and with fever, weight loss, hepatomegaly, ascites, and papular-nodular skin lesions. The clinical and diagnostic aspects involved in the case were discussed. Bacillary angiomatosis must always be considered in the diagnosis of febrile cutaneous manifestations in AIDS.

  8. Geoethical considerations in early warning of flooding and landslides: Case study from Norway

    Science.gov (United States)

    Devoli, Graziella; Kleivane Krøgli, Ingeborg; Dahl, Mads Peter; Colleuille, Hervé; Nykjær Boje, Søren; Sund, Monica

    2015-04-01

    The Norwegian Water Resources and Energy Directorate (NVE) runs the national early warning systems (EWS) for flooding and shallow landslides in Norway. The two EWSs have been operational since the late 1980s and 2013 respectively, and are based on weather forecasts, various hydro-meteorological prognosis and expert evaluation. Daily warning levels and related information to the public is prepared and presented through custom build internet platforms. In natural hazards sciences, the risk of a specific threat is defined as the product of hazard and consequence. In this context an EWS is intended to work as a mitigation measure in lowering the consequence and thus the risk of the threat. One of several factors determining the quality of such an EWS, is how warnings are communicated to the public. In contrary to what is common practice in some other countries, experts working with EWS in Norway cannot be held personally responsible for consequences of warnings being issued or not. However, the communication of warnings for flooding and landslides at NVE still implies many considerations of geoethical kind. Which are the consequences today for the forecasters when erroneous warning messages are sent because based on a poorly documented analysis? What is for example the most responsible way to describe uncertainties in warnings issued? What is the optimal compromise between avoiding false alarms and not sending out a specific warning? Is it responsible to rely on a "gut feeling"? Some authorities complain in receiving warning messages too often. Is it responsible to begin notifying these, only in cases of "high hazard level" and no longer in cases of "moderate hazard level"? Is it acceptable to issue general warnings for large geographical areas without being able to pinpoint the treat on local scale? What responsibility lies within the EWS in recommending evacuation or other practical measures to local authorities? By presenting how early warnings of flooding and

  9. The role of water and sediment connectivity in integrated flood management: a case study on the island of Saint Lucia

    Science.gov (United States)

    Jetten, Victor; van Westen, Cees; Ettema, Janneke; van den Bout, Bastian

    2016-04-01

    Disaster Risk Management combines the effects of natural hazards in time and space, with elements at risk, such as ourselves, infrastructure or other elements that have a value in our society. The risk in this case is defined as the sum of potential consequences of one or more hazards and can be expressed as potential damages. Generally, we attempt to reduce risk by better risk management, such as increase of resilience, protection and spatial planning. Caribbean islands are hit by hurricanes and tropical storms with a frequency of 1 to 2 every 10 years, with devastating consequences in terms of flash floods and landslides. The islands basically consist of a central (volcanic) mountain range, with medium and small sized catchments radiating outward towards the ocean. The coastal zone is inhabited, while the ring road network is essential for functioning of the island. An example of a case study is given for the island of Saint Lucia. Recorded rainfall intensities during tropical storms of 12 rainfall stations surpass 200 mm/h, causing immediate flash floods. Very often however, sediment is a forgotten variable in flash flood management: protection and mitigation measures as well as spatial planning all focus on the hydrology, the extent and depth of flood water, and sometimes of flood velocities. With recent developments, the opensource model LISEM includes hydrology and runoff, flooding, and erosion, transport and deposition both in runoff, channel flow and flood waters. We will discuss the practical solutions we implemented in connecting slopes, river channels and floodplains in terms of water and sediment, and the strength and weaknesses we have encountered so far. Catchment analysis shows two main effects: on the one hand in almost all cases upstream flooding serves as a temporary water storage that prevents further damage downstream, while on the other hand, erosion upstream often blocks bridges and decreases channel storage downstream, which increases the

  10. Flood disaster risk assessment of rural housings--a case study of Kouqian Town in China.

    Science.gov (United States)

    Zhang, Qi; Zhang, Jiquan; Jiang, Liupeng; Liu, Xingpeng; Tong, Zhijun

    2014-04-03

    Floods are a devastating kind of natural disaster. About half of the population in China lives in rural areas. Therefore, it is necessary to assess the flood disaster risk of rural housings. The results are valuable for guiding the rescue and relief goods layout. In this study, we take the severe flood disaster that happened at Kouqian Town in Jilin, China in 2010 as an example to build an risk assessment system for flood disaster on rural housings. Based on the theory of natural disaster risk formation and "3S" technology (remote sensing, geography information systems and global positioning systems), taking the rural housing as the bearing body, we assess the flood disaster risk from three aspects: hazard, exposure and vulnerability. The hazard presented as the flood submerging range and depth. The exposure presented as the values of the housing and the property in it. The vulnerability presented as the relationship between the losses caused by flood and flood depth. We validate the model by the field survey after the flood disaster. The risk assessment results highly coincide with the field survey losses. This model can be used to assess the risk of other flood events in this area.

  11. Flood Disaster Risk Assessment of Rural Housings — A Case Study of Kouqian Town in China

    Directory of Open Access Journals (Sweden)

    Qi Zhang

    2014-04-01

    Full Text Available Floods are a devastating kind of natural disaster. About half of the population in China lives in rural areas. Therefore, it is necessary to assess the flood disaster risk of rural housings. The results are valuable for guiding the rescue and relief goods layout. In this study, we take the severe flood disaster that happened at Kouqian Town in Jilin, China in 2010 as an example to build an risk assessment system for flood disaster on rural housings. Based on the theory of natural disaster risk formation and “3S” technology (remote sensing, geography information systems and global positioning systems, taking the rural housing as the bearing body, we assess the flood disaster risk from three aspects: hazard, exposure and vulnerability. The hazard presented as the flood submerging range and depth. The exposure presented as the values of the housing and the property in it. The vulnerability presented as the relationship between the losses caused by flood and flood depth. We validate the model by the field survey after the flood disaster. The risk assessment results highly coincide with the field survey losses. This model can be used to assess the risk of other flood events in this area.

  12. Flood Risk Management in Remote and Impoverished Areas—A Case Study of Onaville, Haiti

    Directory of Open Access Journals (Sweden)

    Valentin Heimhuber

    2015-07-01

    Full Text Available In this study, geographic information system (GIS-based hydrologic and hydraulic modeling was used to perform a flood risk assessment for Onaville, which is a fairly new, rapidly growing informal settlement that is exposed to dangerous flash-flood events. Since records of historic floods did not exist for the study area, design storms with a variety of significant average return intervals (ARIs were derived from intensity-duration-frequency (IDF curves and transformed into design floods via rainfall-runoff modeling in hydrologic engineering center’s hydrologic modeling system (HEC-HMS. The hydraulic modeling software hydrologic engineering center’s river analysis system (HEC-RAS was used to perform one-dimensional, unsteady-flow simulations of the design floods in the Ravine Lan Couline, which is the major drainage channel of the area. Topographic data comprised a 12 m spatial resolution TanDEM-X digital elevation model (DEM and a 30 cm spatial resolution DEM created with mapping drones. The flow simulations revealed that large areas of the settlement are currently exposed to flood hazard. The results of the hydrologic and hydraulic modeling were incorporated into a flood hazard map which formed the basis for flood risk management. We present a grassroots approach for preventive flood risk management on a community level, which comprises the elaboration of a neighborhood contingency plan and a flood risk awareness campaign together with representatives of the local community of Onaville.

  13. Flood Disaster Risk Assessment of Rural Housings — A Case Study of Kouqian Town in China

    Science.gov (United States)

    Zhang, Qi; Zhang, Jiquan; Jiang, Liupeng; Liu, Xingpeng; Tong, Zhijun

    2014-01-01

    Floods are a devastating kind of natural disaster. About half of the population in China lives in rural areas. Therefore, it is necessary to assess the flood disaster risk of rural housings. The results are valuable for guiding the rescue and relief goods layout. In this study, we take the severe flood disaster that happened at Kouqian Town in Jilin, China in 2010 as an example to build an risk assessment system for flood disaster on rural housings. Based on the theory of natural disaster risk formation and “3S” technology (remote sensing, geography information systems and global positioning systems), taking the rural housing as the bearing body, we assess the flood disaster risk from three aspects: hazard, exposure and vulnerability. The hazard presented as the flood submerging range and depth. The exposure presented as the values of the housing and the property in it. The vulnerability presented as the relationship between the losses caused by flood and flood depth. We validate the model by the field survey after the flood disaster. The risk assessment results highly coincide with the field survey losses. This model can be used to assess the risk of other flood events in this area. PMID:24705363

  14. Economic Efficiency and Equity in Dams Removal: Case studies in Northeastern Massachusetts Doina Oglavie, Ellen Douglas, David Terkla

    Science.gov (United States)

    Oglavie, D. R.; Douglas, E. M.; Terkla, D.

    2009-12-01

    According to American Rivers (www.americanrivers.org), Massachusetts has almost 3,000 dams under state regulation, 296 of which have been classified as high hazard, meaning they pose a serious threat to human life if they should fail. Most of these dams, however, are low head, “run-of-the-river” dams that no longer serve the purpose for which they were built. The presence of these dams has fragmented aquatic and riparian ecosystems, impeded fish passage and generally impacted the natural ecological and hydrological functioning of the streams in which they reside. Dam removal should be considered when a dam no longer serves its function. Although in many cases, the removal of a dam is environmentally beneficial (at least over the long term), sometimes the removal of a dam can incur environmental costs, such as release of contaminants that were sequestered behind the dam. Dam removal is a complex issue especially with respect to privately owned dams. In many cases, dam removal is less costly than dam maintenance or upgrade, hence dam removal decisions tend to be based on purely monetary considerations, and the environmental costs or benefits associated with the dam are not considered. Typically, the main objective for the dam owner is to incur the lowest possible cost (private cost), whether it be operating and maintenance or removal; external costs (environmental degradation) are rarely, if ever, considered, hence the true cost to society is not included in the economic analysis. If dam operation and removal decisions are to be economically efficient, then they have to include both the private costs as well as the external (environmental) costs. The purpose of this work is to 1) attempt to quantify the externalities associated with the maintenance and the removal of dams, 2) assess whether or not the current dam removal evaluation process maximizes social welfare (efficiency and equity) and 3) suggest ways in which this process can be improved by including the

  15. Land Suitability Modeling using a Geographic Socio-Environmental Niche-Based Approach: A Case Study from Northeastern Thailand.

    Science.gov (United States)

    Heumann, Benjamin W; Walsh, Stephen J; Verdery, Ashton M; McDaniel, Phillip M; Rindfuss, Ronald R

    2013-01-01

    Understanding the pattern-process relations of land use/land cover change is an important area of research that provides key insights into human-environment interactions. The suitability or likelihood of occurrence of land use such as agricultural crop types across a human-managed landscape is a central consideration. Recent advances in niche-based, geographic species distribution modeling (SDM) offer a novel approach to understanding land suitability and land use decisions. SDM links species presence-location data with geospatial information and uses machine learning algorithms to develop non-linear and discontinuous species-environment relationships. Here, we apply the MaxEnt (Maximum Entropy) model for land suitability modeling by adapting niche theory to a human-managed landscape. In this article, we use data from an agricultural district in Northeastern Thailand as a case study for examining the relationships between the natural, built, and social environments and the likelihood of crop choice for the commonly grown crops that occur in the Nang Rong District - cassava, heavy rice, and jasmine rice, as well as an emerging crop, fruit trees. Our results indicate that while the natural environment (e.g., elevation and soils) is often the dominant factor in crop likelihood, the likelihood is also influenced by household characteristics, such as household assets and conditions of the neighborhood or built environment. Furthermore, the shape of the land use-environment curves illustrates the non-continuous and non-linear nature of these relationships. This approach demonstrates a novel method of understanding non-linear relationships between land and people. The article concludes with a proposed method for integrating the niche-based rules of land use allocation into a dynamic land use model that can address both allocation and quantity of agricultural crops.

  16. Cases of violence involving transvestites and transsexuals in a northeastern Brazilian city.

    Science.gov (United States)

    Silva, Glauber Weder Dos Santos; Souza, Emanoel Fhilipe Leite; Sena, Romeika Carla Ferreira de; Moura, Izabella Bezerra de Lima; Sobreira, Maura Vanessa Silva; Miranda, Francisco Arnoldo Nunes de

    2016-06-01

    Objective To analyze cases of violence against transvestites and transsexuals based on their sociodemographic profile. Method Cross-sectional, descriptive research performed in Cajazeiras / Paraíba, consisting of 16 transvestites and transsexuals. Data collection took place in April 2014 and was analyzed descriptively. Results The typology of violence that victimized transvestites and transsexuals were: verbal (91.96%), psychological (58.33%) and physical (33.33%), often between 24 hours and six months preceding the survey. Regarding the spatiality: the street, school and health services were all scenarios of aggression. With respect to the offending agent, the findings point towards neighbors, family members and health professionals. All forms of violence happened between agents and spaces of aggression. Conclusions Violence among this population, silence around the situations of abuse became more pronounced as did its invisibility in the social and institutional context, reflecting the inhibition of human rights and concealment of reality.

  17. An operational flash-flood forecasting chain applied to the test cases of the EU project HYDROPTIMET

    Directory of Open Access Journals (Sweden)

    A. C. Taramasso

    2005-01-01

    Full Text Available The application of a flash-flood prediction chain, developed by CIMA, to some testcases for the Tanaro river basin in the framework of the EU project HYDROPTIMET is presented here. The components of the CIMA chain are: forecast rainfall depths, a stochastic downscaling procedure and a hydrological model. Different meteorological Limited Area Models (LAMs provide the rainfall input to the hydrological component. The flash-flood prediction chain is run both in a deterministic and in a probabilistic configuration. The sensitivity of forecasting chain performances to different LAMs providing rainfall forecasts is discussed. The results of the application show how the probabilistic forecasting system can give, especially in the case of convective events, a valuable contribution in addressing the uncertainty at different spatio-temporal scales involved in the flash flood forecasting problem in small and medium basins with complex orography.

  18. Spatial Modeling of Flood Sea Tides (Case Study: East Coast Semarang)

    OpenAIRE

    Muhammad Aris Marfai

    2004-01-01

    The aims of this research are 1) to construct a spatial model of tidal flood hazard, 2) to do hazard analysis of tidal flood. Spatial modelling has been generated using Geographic Information System (GIS) software and ILWIS software was seleccted to do the model operation. Neighborhood function and digital elevation model (DEM) have been applied on the modelling calculation process. DEM data was correted and menipulated using map calculation on the digital form. Tidal flood hazard analysis ha...

  19. Enhancing local action planning through quantitative flood risk analysis: a case study in Spain

    OpenAIRE

    2016-01-01

    This article presents a method to incorporate and promote quantitative risk analysis to support local action planning against flooding. The proposed approach aims to provide a framework for local flood risk analysis, combining hazard mapping with vulnerability data to quantify risk in terms of expected annual affected population, potential injuries, number of fatalities, and economic damages. Flood risk is estimated combining GIS data of loads, system response, and consequen...

  20. Assessment of urban vulnerability towards floods using an indicator-based approach – a case study for Santiago de Chile

    Directory of Open Access Journals (Sweden)

    A. Müller

    2011-08-01

    Full Text Available Regularly occurring flood events do have a history in Santiago de Chile, the capital city of Chile and study area for this research. The analysis of flood events, the resulting damage and its causes are crucial prerequisites for the development of risk prevention measures. The goal of this research is to empirically investigate the vulnerability towards floods in Santiago de Chile as one component of flood risk. The analysis and assessment of vulnerability is based on the application of a multi-scale (individual, household, municipal level set of indicators and the use of a broad range of data. The case-specific set of indicators developed in this study shows the relevant variables and their interrelations influencing the flood vulnerability in the study area. It provides a decision support tool for stakeholders and allows for monitoring and evaluating changes over time. The paper outlines how GIS, census, and remote sensing data as well as household surveys and expert interviews are used as an information base for the derivation of a vulnerability map for two municipalities located in the eastern part of Santiago de Chile. The generation of vulnerability maps representing the two different perspectives of local decision makers (experts and affected households is exemplified and discussed using the developed methodology.

  1. Application of HEC-RAS for flood forecasting in perched river-A case study of hilly region, China

    Science.gov (United States)

    Sun, Pingping; Wang, Shuqian; Gan, Hong; Liu, Bin; Jia, Ling

    2017-04-01

    Flooding in small and medium rivers are seriously threatening the safety of human beings’ life and property. The simulation forecasting of the river flood and bank risk in hilly region has gradually become a hotspot. At present, there are few studies on the simulation of hilly perched river, especially in the case of lacking section flow data. And the method of how to determine the position of the levee breach along the river bank is not much enough. Based on the characteristics of the sections in hilly perched river, an attempt is applied in this paper which establishes the correlation between the flow profile computed by HEC-RAS model and the river bank. A hilly perched river in Lingshi County, Shanxi Province of China, is taken as the study object, the levee breach positions along the bank are simulated under four different design storm. The results show that the flood control standard of upper reach is high, which can withstand the design storm of 100 years. The current standard of lower reach is low, which is the flooding channel with high frequency. As the standard of current channel between the 2rd and the 11th section is low, levee along that channel of the river bank is considered to be heighten and reinforced. The study results can provide some technical support for flood proofing in hilly region and some reference for the reinforcement of river bank.

  2. Urban Floods in Lowlands—Levee Systems, Unplanned Urban Growth and River Restoration Alternative: A Case Study in Brazil

    Directory of Open Access Journals (Sweden)

    Marcelo Gomes Miguez

    2015-08-01

    Full Text Available The development of cities has always had a very close relation with water. However, cities directly impact land use patterns and greatly change natural landscapes, aggravating floods. Considering this situation, this paper intends to discuss lowland occupation and city sustainability in what regards urban stormwater management, fluvial space, and river restoration, aiming at minimizing flood risks and improving natural and built environment conditions. River plains tend to be attractive places for a city to grow. From ancient times, levees have been used to protect lowland areas along major watercourses to allow their occupation. However, urban rivers demand space for temporary flood storage. From a systemic point of view, levees along extensive river reaches act as canalization works, limiting river connectivity with flood plains, rising water levels, increasing overtopping risks and transferring floods downstream. Departing from this discussion, four case studies in the Iguaçu-Sarapuí River Basin, a lowland area of Rio de Janeiro State, Brazil, are used to compose a perspective in which the central point refers to the need of respecting watershed limits and giving space to rivers. Different aspects of low-lying city planning are discussed and analyzed concerning the integration of the built and natural environments.

  3. Two dimensional modelling of flood flows and suspended sedimenttransport: the case of the Brenta River, Veneto (Italy

    Directory of Open Access Journals (Sweden)

    P. Martini

    2004-01-01

    Full Text Available The paper presents a numerical model for the simulation of flood waves and suspended sediment transport in a lowland river basin of North Eastern Italy. The two dimensional depth integrated momentum and continuity equations are modified to take into account the bottom irregularities that strongly affect the hydrodynamics in partially dry areas, as for example, in the first stages of an inundation process or in tidal flow. The set of equations are solved with a standard Galerkin finite element method using a semi-implicit numerical scheme where the effects of both the small channel network and the regulation devices on the flood wave propagation are accounted for. Transport of suspended sediment and bed evolution are coupled with the hydrodynamics using an appropriate form of the advection-dispersion equation and Exner's equation. Applications to a case study are presented in which the effects of extreme flooding on the Brenta River (Italy are examined. Urban and rural flood risk areas are identified and the effects of a alleviating action based on a diversion channel flowing into Venice Lagoon are simulated. The results show that this solution strongly reduces the flood risk in the downstream areas and can provide an important source of sediment for the Venice Lagoon. Finally, preliminary results of the sediment dispersion due to currents and waves in the Venice Lagoon are presented.

  4. Estimation of the relative severity of floods in small ungauged catchments for preliminary observations on flash flood preparedness: a case study in Korea.

    Science.gov (United States)

    Kim, Eung Seok; Choi, Hyun Il

    2012-04-01

    An increase in the occurrence of sudden local flooding of great volume and short duration has caused significant danger and loss of life and property in Korea as well as many other parts of the World. Since such floods usually accompanied by rapid runoff and debris flow rise quite quickly with little or no advance warning to prevent flood damage, this study presents a new flash flood indexing methodology to promptly provide preliminary observations regarding emergency preparedness and response to flash flood disasters in small ungauged catchments. Flood runoff hydrographs are generated from a rainfall-runoff model for the annual maximum rainfall series of long-term observed data in the two selected small ungauged catchments. The relative flood severity factors quantifying characteristics of flood runoff hydrographs are standardized by the highest recorded maximum value, and then averaged to obtain the flash flood index only for flash flood events in each study catchment. It is expected that the regression equations between the proposed flash flood index and rainfall characteristics can provide the basis database of the preliminary information for forecasting the local flood severity in order to facilitate flash flood preparedness in small ungauged catchments.

  5. Real-time Monitoring and Simulating of Urban Flood, a Case Study in Guangzhou

    Science.gov (United States)

    Huang, H.; Wang, X.; Zhang, S.; Liu, Y.

    2014-12-01

    In recent years urban flood frequently occurred and seriously impacted city's normal operation, particular on transportation. The increase of urban flood could be attributed to many factors, such as the increase of impervious land surface and extreme precipitation, the decrease of surface storage capacity, poor maintenance of drainage utilities, and so on. In order to provide accurate and leading prediction on urban flooding, this study acquires precise urban topographic data via air-borne Lidar system, collects detailed underground drainage pipes, and installs in-situ monitoring networks on precipitation, water level, video record and traffic speed in the downtown area of Panyu District, Guangzhou, China. Based on the above data acquired, a urban flood model with EPA SWMM5 is established to simulate the flooding and inundation processes in the study area of 20 km2. The model is driven by the real-time precipitation data and calibrated by the water level data, which are converted to flooding volume with precise topographic data. After calibration, the model could be employed to conduct sensitivity analysis for investigating primary factors of urban flooding, and to simulate the flooding processes in different scenarios, which are beneficial to assessment of flooding risk and drainage capacity. This model is expected to provide real-time forecasting in emergency management.

  6. Real-time flood inundation forecasting and mapping for key railway infrastructure: a UK case study

    Directory of Open Access Journals (Sweden)

    Murphy Alexandra T.

    2016-01-01

    Full Text Available Flooding events that impede railway infrastructure can cause severe travel delays for the general public and large fines in delayed minutes for the rail industry. Early warnings of flood inundation can give more time to implement mitigation measures which help reduce cancellations, delays and fines. Initial work is reported on the development of a real-time flood inundation forecasting and mapping system for the Cowley Bridge track area near Exeter, UK. This location is on one of the main access routes to South West England and has suffered major floods in the past resulting in significant transport impacts. Flood forecasting systems in the UK mainly forecast river level/flow rather than extent and depth of flood inundation. Here, the development of a chain of coupled models is discussed that link rainfall to river flow, river level and flood extent for the rail track area relating to Cowley Bridge. Historical events are identified to test model performance in predicting inundation of railway infrastructure. The modelling system will operate alongside a series of in-situ sensors chosen to enhance the flood mapping forecasting system. Sensor data will support offline model calibration/verification and real-time data assimilation as well as monitoring flood conditions to inform track closure decisions.

  7. Proposal for an index to classify irrigation water quality: a case study in northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Celsemy Eleutério Maia

    2012-06-01

    Full Text Available One way of classifying water quality is by means of indices, in which a series of parameters analyzed are joined a single value, facilitating the interpretation of extensive lists of variables or indicators, underlying the classification of water quality. The objective of this study was to develop a statistically based index to classify water according to the Irrigation Water Quality Index (IWQI, to evaluate the ionic composition of water for use in irrigation and classify it by its source. For this purpose, the database generated during the Technology Generation and Adaptation (GAT program was used, in which, as of 1988, water samples were collected monthly from water sources in the states of Paraíba, Rio Grande do Norte and Ceará. To evaluate water quality, the electrical conductivity (EC of irrigation water was taken as a reference, with values corresponding to 0.7 dS m-1. The chemical variables used in this study were: pH, EC, Ca, Mg, Na, K, Cl, HCO3, CO3, and SO4. The data of all characteristics evaluated were standardized and data normality was confirmed by Lilliefors test. Then the irrigation water quality index was determined by an equation that relates the standardized value of the variable with the number of characteristics evaluated. Thus, the IWQI was classified based on indices, considering normal distribution. Finally, these indices were subjected to regression analysis. The method proposed for the IWQI allowed a satisfactory classification of the irrigation water quality, being able to estimate it as a function of EC for the three water sources. Variation in the ionic composition was observed among the three sources and within a single source. Although the water quality differed, it was good in most cases, with the classification IWQI II.

  8. Taking climate change into estimation of long-term flood risks: A case of Devils Lake of North Dakota, USA

    Science.gov (United States)

    Kharel, G.; Kirilenko, A.

    2014-12-01

    Terminal lakes are heavily impacted by regional changes in climate. Devils Lake (DL) is a terminal lake located in the northeastern North Dakota of the US. Since 1990, following a shift in regional precipitation pattern, DL has encountered a 10 m water level rise, with over 400% increase in surface area and 600% increase in water volume, costing over $1.5 billion in mitigation. Currently, the lake is River with potential negative consequences for downstream water quality and flooding. Recently, the artificial outlets have been constructed and operated to divert DL water to the Sheyenne River amid legal and political pressure. Outlet construction however did not take into consideration possible changes in local climate. We modeled the DL basin ( 9,800 km2) hydrology using the Soil and Water Assessment Tool (SWAT) and estimated future water levels of DL for different outlet scenarios under three Intergovernmental Panel on Climate Change (IPCC) SRES scenarios (A1B, B1 & A2) for 2020s and 2050s. We evaluated model performance by comparing SWAT simulated daily streamflow outputs against the observed streamflow data recorded at 6 USGS water gauge locations within the basin. Future climate conditions in the region were estimated by combining historical weather data (1981-2010), 15 CMIP3 General Circulation Model projections from the IPCC data center, and stochastic downscaling methodology (LARS-WG). Our results indicate significant likelihood (7.3% ̶ 20.0%) of uncontrolled DL water overspill in the next few decades in the absence of outlets, with some members of GCM integration ensemble carrying over 85.0% and 95.0% overspill probability for 2020s and 2050s respectively. However, full-capacity outlets show radical reduction in overspill probability to partially mitigate the flooding problem by decreasing the average lake level by approximately 1.9 m and 1.5 m in 2020s and 2050s. Moreover, had there been outlet operation from the beginning of the flood episode since 1990s

  9. Assessing the environmental justice consequences of flood risk: a case study in Miami, Florida

    Science.gov (United States)

    Montgomery, Marilyn C.; Chakraborty, Jayajit

    2015-09-01

    Recent environmental justice (EJ) research has emphasized the need to analyze social inequities in the distribution of natural hazards such as hurricanes and floods, and examine intra-ethnic diversity in patterns of EJ. This study contributes to the emerging EJ scholarship on exposure to flooding and ethnic heterogeneity by analyzing the racial/ethnic and socioeconomic characteristics of the population residing within coastal and inland flood risk zones in the Miami Metropolitan Statistical Area (MSA), Florida—one of the most ethnically diverse MSAs in the U.S. and one of the most hurricane-prone areas in the world. We examine coastal and inland flood zones separately because of differences in amenities such as water views and beach access. Instead of treating the Hispanic population as a homogenous group, we disaggregate the Hispanic category into relevant country-of-origin subgroups. Inequities in flood risk exposure are statistically analyzed using socio-demographic variables derived from the 2010 U.S. Census and 2007-2011 American Community Survey estimates, and 100-year flood risk zones from the Federal Emergency Management Agency (FEMA). Social vulnerability is represented with two neighborhood deprivation indices called economic insecurity and instability. We also analyze the presence of seasonal/vacation homes and proximity to public beach access sites as water-related amenity variables. Logistic regression modeling is utilized to estimate the odds of neighborhood-level exposure to coastal and inland 100-year flood risks. Results indicate that neighborhoods with greater percentages of non-Hispanic Blacks, Hispanics, and Hispanic subgroups of Colombians and Puerto Ricans are exposed to inland flood risks in areas without water-related amenities, while Mexicans are inequitably exposed to coastal flood risks. Our findings demonstrate the importance of treating coastal and inland flood risks separately while controlling for water-related amenities, and

  10. Rapid Global River Flood Risk Assessment under Climate and Socioeconomic Scenarios: An Extreme Case of Eurasian region

    Science.gov (United States)

    Kwak, Young-joo; Magome, Jun; Hasegawa, Akira; Iwami, Yoichi

    2017-04-01

    Causing widespread devastation with massive economic damage and loss of human lives, flood disasters hamper economic growth and accelerate poverty particularly in developing countries. Globally, this trend will likely continue due to increase in flood magnitude and lack of preparedness for extreme events. In line with risk reduction efforts since the early 21st century, the monitors and governors of global river floods should pay attention to international scientific and policy communities for support to facilitate evidence-based policy making with a special interest in long-term changes due to climate change and socio-economic effects. Although advanced hydrological inundation models and risk models have been developed to reveal flood risk, hazard, exposure, and vulnerability at a river basin, it is obviously hard to identify the distribution and locations of continent-level flood risk based on national-level data. Therefore, we propose a methodological possibility for rapid global flood risk assessment with the results from its application to the two periods, i.e., Present (from 1980 to 2004) and Future (from 2075 to 2099). The method is particularly designed to effectively simplify complexities of a hazard area by calculating the differential inundation depth using GFID2M (global flood inundation depth 2-dimension model), despite low data availability. In this research, we addressed the question of which parts in the Eurasian region (8E to 180E, 0N to 60N) can be found as high-risk areas in terms of exposed population and economy in case of a 50-year return period flood. Economic losses were estimated according to the Shared Socioeconomic Pathways (SSP) scenario, and the flood scale was defined using the annual maximum daily river discharge under the extreme conditions of climate change simulated with MRI-AGCM3.2S based on the Representative Concentration Pathways (RCP8.5) emissions scenario. As a preliminary result, the total potential economic loss in the

  11. Structuring Climate Adaptation through Multiple Perspectives: Framework and Case Study on Flood Risk Management

    Directory of Open Access Journals (Sweden)

    Mohanasundar Radhakrishnan

    2017-02-01

    Full Text Available Adaptation to climate change is being addressed in many domains. This means that there are multiple perspectives on adaptation; often with differing visions resulting in disconnected responses and outcomes. Combining singular perspectives into coherent, combined perspectives that include multiple needs and visions can help to deepen the understanding of various aspects of adaptation and provide more effective responses. Such combinations of perspectives can help to increase the range and variety of adaptation measures available for implementation or avoid maladaptation compared with adaptations derived from a singular perspective. The objective of this paper is to present and demonstrate a framework for structuring the local adaptation responses using the inputs from multiple perspectives. The adaptation response framing has been done by: (i contextualizing climate change adaptation needs; (ii analyzing drivers of change; (iii characterizing measures of adaptation; and (iv establishing links between the measures with a particular emphasis on taking account of multiple perspectives. This framework was demonstrated with reference to the management of flood risks in a case study Can Tho, Vietnam. The results from the case study show that framing of adaptation responses from multiple perspectives can enhance the understanding of adaptation measures, thereby helping to bring about more flexible implementation practices.

  12. Legitimate adaptive flood risk governance beyond the dikes: the cases of Hamburg, Helsinki and Rotterdam

    NARCIS (Netherlands)

    Mees, H.L.P.; Driessen, P.P.J.; Runhaar, H.A.C.

    2013-01-01

    It has recently been recommended that a shift from traditional flood prevention to more adaptive strategies is made, focusing on the reduction in and recovery from flood impacts as a means to improve resilience to climate impacts. This shift has had implications for the public–private divide in

  13. The role of knowledge in greening flood protection. Lessons from the Dutch case study future Afsluitdijk

    NARCIS (Netherlands)

    Janssen, S.K.H.; Mol, A.P.J.; Tatenhove, van J.; Otter, H.S.

    2014-01-01

    Greening flood protection (GFP) is an upcoming approach in coastal protection knowledge and policy. The central notion of this multifunctional concept is that natural processes, nature development and the dynamics of ecosystems are taken into account in realising flood protection. In practice, imple

  14. Flooding and emergency room visits for gastrointestinal illness in Massachusetts: A case-crossover study.

    Science.gov (United States)

    Introduction: Floods and other severe weather events are anticipated to increase as a result of global climate change. Floods can lead to outbreaks of gastroenteritis and other infectious diseases due to disruption of sewage and water infrastructure and impacts on san...

  15. Interdisciplinary Approach for Assessment of Continental River Flood Risk: A Case Study of the Czech Republic

    Science.gov (United States)

    Ushiyama, Tomoki; Kwak, Youngjoo; Ledvinka, Ondřej; Iwami, Yoichi; Danhelka, Jan

    2017-04-01

    In this research, GIS-based hydrological model-driven approach produces the distribution of continent-level flood risk based on national-level GIS data. In order to reveal flood hazard, exposure, and vulnerability in a large river basin, the system employs the simplified model such as GFiD2M (Global Flood inundation Depth 2-dimension Model) to calculate the differential inundation depth and the economic loss by pixel-based statistical processing, considering climate and socioeconomic scenarios, the representative concentration pathways emissions and the shared socioeconomic pathways, despite current limitations of data collections and poor data availability. We need new approaches to seek the possibility of its national-scale application, so that the framework can bring (1) improved flood inundation map (i.e., discharge, depth, velocity) using rainfall runoff inundation model, based on the in-situ data (rain-gauge and water level), validated with Earth Observation data, i.e., MODIS, (2) advanced flood forecasting using radar and satellite observed rainfall for national-level operational hydrological observations, (3) potential economic impact with the effect of flood hazard and risk under climate and socioeconomic changes based on rainfall from general circulation model. The preliminary examinations showed the better possibility of a nation-wide application for integrated flood risk management. At the same time, the hazard and risk model were also validated against event-based flood inundation of a national-level flood in the Czech Republic. Within the Czech Republic, although radar rainfall data have been used in operational hydrology for some time, there are also other products capable of warning us about the potential risk of floods. For instance, images from Europe's Sentinel satellites have not been evaluated for their use in Czech hydrology. This research is at the very beginning of a validation and its evaluation, focusing mainly on heavy rainfall and

  16. Taking the heterogeneity of citizens into account: flood risk communication in coastal cities – a case study of Bremen

    Directory of Open Access Journals (Sweden)

    T. Martens

    2009-11-01

    Full Text Available The likely manifestations of climate change like flood hazards are prominent topics in public communication. This can be shown by media analysis and questionnaire data. However, in the case of flood risks an information gap remains resulting in misinformed citizens who probably will not perform the necessary protective actions when an emergency occurs. This paper examines more closely a newly developed approach to flood risk communication that takes the heterogeneity of citizens into account and aims to close this gap. The heterogeneity is analysed on the meso level regarding differences in residential situation as well as on the micro level with respect to risk perception and protective actions. Using the city of Bremen as a case study, empirical data from n=831 respondents were used to identify Action Types representing different states of readiness for protective actions in view of flood risks. These subpopulations can be provided with specific information to meet their heterogeneous needs for risk communication. A prototype of a computer-based information system is described that can produce and pass on such tailored information. However, such an approach to risk communication has to be complemented by meso level analysis which takes the social diversity of subpopulations into account. Social vulnerability is the crucial concept for understanding the distribution of resources and capacities among different social groups. We therefore recommend putting forums and organisations into place that can mediate between the state and its citizens.

  17. Flood Modeling and Simulation using iRIC: A Case Study of Kabul City

    Directory of Open Access Journals (Sweden)

    Shokory Jamal Abdul Naser

    2016-01-01

    Full Text Available In Afghanistan, floods are common and measures must be taken to protect people and property from damage. There is, however, a lack of detailed observations and research on this subject in this area. Therefore, flood simulation models are needed to identify flood-prone areas. In this study, International River Interface Cooperative (iRIC program that is river flow and riverbed variation analysis software with several solvers has been used. Nays2DFlood solver that simulates 2dimenstional plane flow has applied to a past flood in Kabul city. River discharge from two inflow points and averaged precipitation from three rain gauges at the time of flooding given as input to the model including DEM (Digital Elevation Model data. The iRIC was confirmed as a 90-m grid digital elevation model to determine the position of streamlines correctly. However, the highest flood depth was overestimated because the 90-m grids were too coarse to detect the slight slope of the riverbed in some areas. Then the elevation of the riverbed modified using data acquired from Google Earth, and the simulation results improved. Moreover, it was found that river water rather than rainfall was the main cause of the flooding.

  18. The resilience of neighborhood social processes: A case study of the 2011 Brisbane flood.

    Science.gov (United States)

    Wickes, Rebecca; Britt, Chester; Broidy, Lisa

    2017-02-01

    Social disorganization theories position neighborhood social capital and collective efficacy as key social processes that should facilitate community resilience in the aftermath of disaster. Yet limited evidence demonstrates that these social processes are themselves resilient with some studies showing that disaster can fracture even once cohesive neighborhoods. In this paper we assess the stability of neighborhood level collective efficacy and social capital before and after a disaster. We use multilevel structural equation modeling and draw on census and longitudinal survey data collected from over 4000 residents living in 148 neighborhoods in Brisbane, Australia before and after a significant flood event. We examine what happens to social capital and collective efficacy in flooded and non-flooded neighborhoods and assess whether demographic shifts are associated with change and/or stability in these processes. We find strong evidence that these processes operate similarly across flooded and not flooded communities. Our findings also reveal significant stability for our measures of social capital across time, while collective efficacy increases post flood across all neighborhoods, but more so in flooded neighborhoods. Neighborhood demographics have limited effect on patterns of stability or change in these social processes. We discuss the theoretical and practical implications of these findings for our understanding of neighborhood resilience in the wake of disaster.

  19. Human papillomavirus (HPV) infection in a case-control study of oral squamous cell carcinoma and its increasing trend in northeastern Thailand.

    Science.gov (United States)

    Phusingha, Pensiri; Ekalaksananan, Tipaya; Vatanasapt, Patravoot; Loyha, Kulchaya; Promthet, Supannee; Kongyingyoes, Bunkerd; Patarapadungkit, Natcha; Chuerduangphui, Jureeporn; Pientong, Chamsai

    2016-12-09

    Human papillomavirus (HPV) is an independent risk factor for development of oral squamous cell carcinoma (OSCC). This study aimed to investigate the role of HPV infection and the trend in percentage of HPV-associated OSCC over a 5-year period in northeastern Thailand. In this case-control study, 91 exfoliated oral cell samples and 80 lesion cell samples from OSCC cases and exfoliated oral cells from 100 age/gender-matched controls were collected. HPV infection was investigated by PCR using GP5+/GP6+ primers followed by HPV genotyping using reverse line blot hybridization. Quantitative RT-PCR was used to evaluate HPV oncogene transcription. Temporal trends of HPV infection were evaluated in archived formalin-fixed paraffin-embedded (FFPE) OSCC tissues using in situ hybridization. HPV DNA was found in 17.5% (14/80) of lesion samples from OSCC cases and 29.7% (27/91) of exfoliated oral cell samples from the same cases. These values were significantly higher than in exfoliated oral cell samples from controls (13%, 13/100). HPV-16 was the genotype most frequently found in OSCC cases (92.8%, 13/14 infected cases). Interestingly, HPV oncogene mRNA expression was detected and correlated with OSCC cases (P HPV DNA and 64 (43.8%) cases were positive for HPV E6/E7 mRNA expression. There was a trend of increasing percentage of HPV-associated OSCC from 2005 to 2010. This was especially so for females with well-differentiated tumors in specific tongue sub-sites. We suggest that HPV infection plays an important role in oral carcinogenesis in northeastern Thailand.

  20. Holistic flood risk assessment using agent-based modelling: the case of Sint Maarten Island

    Science.gov (United States)

    Abayneh Abebe, Yared; Vojinovic, Zoran; Nikolic, Igor; Hammond, Michael; Sanchez, Arlex; Pelling, Mark

    2015-04-01

    Floods in coastal regions are regarded as one of the most dangerous and harmful disasters. Though commonly referred to as natural disasters, coastal floods are also attributable to various social, economic, historical and political issues. Rapid urbanisation in coastal areas combined with climate change and poor governance can lead to a significant increase in the risk of pluvial flooding coinciding with fluvial and coastal flooding posing a greater risk of devastation in coastal communities. Disasters that can be triggered by hydro-meteorological events are interconnected and interrelated with both human activities and natural processes. They, therefore, require holistic approaches to help understand their complexity in order to design and develop adaptive risk management approaches that minimise social and economic losses and environmental impacts, and increase resilience to such events. Being located in the North Atlantic Ocean, Sint Maarten is frequently subjected to hurricanes. In addition, the stormwater catchments and streams on Sint Maarten have several unique characteristics that contribute to the severity of flood-related impacts. Urban environments are usually situated in low-lying areas, with little consideration for stormwater drainage, and as such are subject to flash flooding. Hence, Sint Maarten authorities drafted policies to minimise the risk of flood-related disasters on the island. In this study, an agent-based model is designed and applied to understand the implications of introduced policies and regulations, and to understand how different actors' behaviours influence the formation, propagation and accumulation of flood risk. The agent-based model built for this study is based on the MAIA meta-model, which helps to decompose, structure and conceptualize socio-technical systems with an agent-oriented perspective, and is developed using the NetLogo simulation environment. The agents described in this model are households and businesses, and

  1. A comparison of five flood rain events over the New South Wales north coast and a case study

    Science.gov (United States)

    Speer, Milton S.; Leslie, Lance M.

    2000-04-01

    One of the most significant forecasting problems facing meteorologists in the Sydney office of the Australian Bureau of Meteorology is the prediction of the heavy to extreme rainfall amounts that occur on the subtropical north coast of New South Wales (NSW). The significance of the problem lies in the great intensity of the rainfall, the difficulty in predicting the formation, location and duration of the rainfall, and the impacts of flooding on both cities and communities. The forecasting difficulties arise because of the small scales often involved, the range of physical mechanisms responsible and the challenge involved in forecasting events of such short duration. In the case of flash floods, the intense rainfall is typically less than 6 h in duration. Operational numerical weather prediction (NWP) has not shown much success, mainly because of the reasons mentioned above, especially given that computational limitations restrict its model resolutions.In this paper, the synoptic situation is presented for the most severe flash flood on record to affect Coffs Harbour, a city which is located on the NSW mid-north coast. The event, which occurred on the evening of 23 November 1996, is rated approximately as a 1 in a 100-year intensity/duration event. A 25-year climatology subset of flood-producing systems that have affected Coffs Harbour is then presented, and is correlated with the Southern Oscillation Index (SOI). Finally, details are given for a numerical modelling case study of the flash flood. The model results reveal that a very accurate prediction of the amount and the spatial distribution of rainfall amounts can be made for an event of this type. The rainfall totals of over 500 mm in 24 h were accurately forecast using coarse resolution archived operational initial analyses. The success of the predictions is most likely owing to the dominance of large-scale dynamical processes, which were further focused by the steep topography.

  2. Environmental health aspects of drinking water-borne outbreak due to karst flooding: case study.

    Science.gov (United States)

    Dura, Gyula; Pándics, Tamás; Kádár, Mihály; Krisztalovics, Katalin; Kiss, Zoltánné; Bodnár, Judit; Asztalos, Agnes; Papp, Erzsébet

    2010-09-01

    Climate change may increase the incidence of waterborne diseases due to extreme rainfall events, and consequent microbiological contamination of the water source and supply. As a result of the complexity of the pathways from the surface to the consumer, it is difficult to detect an association between rainfall and human disease. The water supply of a Hungarian city, Miskolc (174,000 inhabitant), is mainly based on karstic water, a vulnerable underground water body. A large amount of precipitation fell on the catchment area of the karstic water source, causing an unusually strong karstic water flow and flooding, and subsequent microbiological contamination. The presence of several potential sources of contamination in the protective zone of the karstic water source should be emphasized. The water supplier was unprepared to treat the risk of waterborne outbreak caused by an extreme weather event. Public health intervention and hygienic measures were taken in line with epidemiological actions, focusing on the protection of consumers by providing safe drinking water. The contamination was identified, and measures were taken for risk reduction and prevention. This case study underlines the increasing importance of preparedness for extreme water events in order to protect the karstic water sources and to avoid waterborne outbreaks.

  3. Tool for analyzing the vulnerability of buildings to flooding: the case of Switzerland

    Science.gov (United States)

    Choffet, Marc; Bianchi, Renzo; Jaboyedoff, Michel; Kölz, Ehrfried; Lateltin, Olivier; Leroi, Eric; Mayis, Arnaud

    2010-05-01

    Whatever the way used to protect property exposed to flood, there exists a residual risk. That is what feedbacks of past flooding show. This residual risk is on one hand linked with the possibility that the protection measures may fail or may not work as intended. The residual risk is on the other hand linked with the possibility that the flood exceeds the chosen level of protection.In many European countries, governments and insurance companies are thinking in terms of vulnerability reduction. This publication will present a new tool to evaluate the vulnerability of buildings in a context of flooding. This tool is developed by the project "Analysis of the vulnerability of buildings to flooding" which is funded by the Foundation for Prevention of Cantonal insurances, Switzerland. It is composed by three modules and it aims to provide a method for reducing the vulnerability of buildings to flooding. The first two modules allow identifying all the elements composing the building and listing it. The third module is dedicated to the choice of efficient risk reducing measures on the basis of cost-benefit analyses. The diagnostic tool for different parts of the building is being developed to allow real estate appraisers, insurance companies and homeowners rapidly assess the vulnerability of buildings in flood prone areas. The tool works with by several databases that have been selected from the collection and analysis of data, information, standards and feedback from risk management, hydrology, architecture, construction, materials engineering, insurance, or economy of construction. A method for determining the local hazard is also proposed, to determine the height of potential floods threatening a building, based on a back analysis of Swiss hazard maps. To calibrate the model, seven cantonal insurance institutions participate in the study by providing data, such as the the amount of damage in flooded areas. The poster will present some results from the development of

  4. Integrated flood disaster management and spatial information: Case studies of Netherlands and India

    NARCIS (Netherlands)

    Zlatanova, S.; Ghawana, T.; Kaur, A.; Neuvel, J.M.M.

    2014-01-01

    Spatial Information is an integral part of flood management practices which include risk management & emergency response processes. Although risk & emergency management activities have their own characteristics, for example, related to the time scales, time pressure, activities & actors involved, it

  5. Integrated flood disaster management and spatial information: Case studies of Netherlands and India

    NARCIS (Netherlands)

    Zlatanova, S.; Ghawana, T.; Kaur, A.; Neuvel, J.M.M.

    2014-01-01

    Spatial Information is an integral part of flood management practices which include risk management & emergency response processes. Although risk & emergency management activities have their own characteristics, for example, related to the time scales, time pressure, activities & actors involved, it

  6. Interaction between urban spatial organization and flood risk, Taipei case study

    OpenAIRE

    2011-01-01

    8 p.; International audience; Nowadays, the dikes and high walls constructions in the water shore are the solution to protect from flooding in urban areas. However, the rapid and dense urbanization also the climate change indicate the danger of this solution. The urban planning recent research proposes to preserve and to make urban space for water in order to contribute on flood risk management. By this concept, water could be considered as one of urban key components which trace over urban c...

  7. Comprehensive benefit of flood resources utilization through dynamic successive fuzzy evaluation model: A case study

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Taking the flood resources utilization in Baicheng, Jilin during 2002–2007 as the research background, and based on the entropy weight and multi-level & multi-objective fuzzy optimization theory, this research established a multi-level & semi-constructive index system and dynamic successive evaluation model for comprehensive benefit evaluation of regional flood resources utilization. With the year 2002 as the base year, the analyzing results showed that there existed a close positive correlation between flood utilization volume and its benefits, comprehensive evaluation value and its comparison increment. Within the six successive evaluation years, the comprehensive benefit of 2003 was the best, in which the benefit evaluation increment reached 82.8% whereas the year of 2004 was the worst, in which the increment was only 18.2%. Thus the sustainability and correctness of the evaluation were verified by six years successive evaluation and increment comparison. The analyzing results showed that the economic benefits, ecological benefits and social benefits of flood utilization were remarkable, and that the comprehensive benefit could be improved by increasing flood utilization capacity, which would promote the regional sustainable development as well. The established dynamic successive evaluation provides a stable theoretical basis and technical support for further flood utilization.

  8. Enhancing local action planning through quantitative flood risk analysis: a case study in Spain

    Science.gov (United States)

    Castillo-Rodríguez, Jesica Tamara; Escuder-Bueno, Ignacio; Perales-Momparler, Sara; Ramón Porta-Sancho, Juan

    2016-07-01

    This article presents a method to incorporate and promote quantitative risk analysis to support local action planning against flooding. The proposed approach aims to provide a framework for local flood risk analysis, combining hazard mapping with vulnerability data to quantify risk in terms of expected annual affected population, potential injuries, number of fatalities, and economic damages. Flood risk is estimated combining GIS data of loads, system response, and consequences and using event tree modelling for risk calculation. The study area is the city of Oliva, located on the eastern coast of Spain. Results from risk modelling have been used to inform local action planning and to assess the benefits of structural and non-structural risk reduction measures. Results show the potential impact on risk reduction of flood defences and improved warning communication schemes through local action planning: societal flood risk (in terms of annual expected affected population) would be reduced up to 51 % by combining both structural and non-structural measures. In addition, the effect of seasonal population variability is analysed (annual expected affected population ranges from 82 to 107 %, compared with the current situation, depending on occupancy rates in hotels and campsites). Results highlight the need for robust and standardized methods for urban flood risk analysis replicability at regional and national scale.

  9. Urban floods: a case study in the Savigliano area (North-Western Italy

    Directory of Open Access Journals (Sweden)

    C. Audisio

    2011-11-01

    Full Text Available Flood processes and effects are examined, concerning two rivers in an urbanized area in North-Western Italy (Piedmont – Cuneo Plain. In May 2008, some areas in Northern Italy were struck by intense and persistent rainfall. In the Cuneo province (Southern Piedmont, floodplain with some urban areas was inundated over ca. ten square kilometres, and the city of Savigliano (about 21 000 inhabitants was particularly hit by flood. A purposely-made historical research has evidenced approximately fifty flood events as having occurred since 1350 in the Savigliano area. Based upon historical data, both documents and maps, GIS (Geographical Information System technique and field surveys were used to quantitatively assess the growing urbanization of the city and to describe flood processes and effects over years. This work aims to describe the dynamic behaviour of the 2008 flood, also comparing it to past events, in particular those that occurred in 1896. It is emphasized how the knowledge of past events can be helpful in reducing urban flooding.

  10. Flood insurance in Canada: implications for flood management and residential vulnerability to flood hazards.

    Science.gov (United States)

    Oulahen, Greg

    2015-03-01

    Insurance coverage of damage caused by overland flooding is currently not available to Canadian homeowners. As flood disaster losses and water damage claims both trend upward, insurers in Canada are considering offering residential flood coverage in order to properly underwrite the risk and extend their business. If private flood insurance is introduced in Canada, it will have implications for the current regime of public flood management and for residential vulnerability to flood hazards. This paper engages many of the competing issues surrounding the privatization of flood risk by addressing questions about whether flood insurance can be an effective tool in limiting exposure to the hazard and how it would exacerbate already unequal vulnerability. A case study investigates willingness to pay for flood insurance among residents in Metro Vancouver and how attitudes about insurance relate to other factors that determine residential vulnerability to flood hazards. Findings indicate that demand for flood insurance is part of a complex, dialectical set of determinants of vulnerability.

  11. Flood Insurance in Canada: Implications for Flood Management and Residential Vulnerability to Flood Hazards

    Science.gov (United States)

    Oulahen, Greg

    2015-03-01

    Insurance coverage of damage caused by overland flooding is currently not available to Canadian homeowners. As flood disaster losses and water damage claims both trend upward, insurers in Canada are considering offering residential flood coverage in order to properly underwrite the risk and extend their business. If private flood insurance is introduced in Canada, it will have implications for the current regime of public flood management and for residential vulnerability to flood hazards. This paper engages many of the competing issues surrounding the privatization of flood risk by addressing questions about whether flood insurance can be an effective tool in limiting exposure to the hazard and how it would exacerbate already unequal vulnerability. A case study investigates willingness to pay for flood insurance among residents in Metro Vancouver and how attitudes about insurance relate to other factors that determine residential vulnerability to flood hazards. Findings indicate that demand for flood insurance is part of a complex, dialectical set of determinants of vulnerability.

  12. Flood Management and Protection from the Social Point of View: Case Study from Ukraine

    Science.gov (United States)

    Manukalo, V.; Gerasymenko, H.

    2012-12-01

    Defining Issue According to the statistics presented by the Ministry of Emergencies of Ukraine, river floods have imposed the most severe damages to the sectors of economy and the human communities in Ukraine. But, an adaptability and a vulnerability of Ukrainian society to floods are still poorly understood. Results Presentation In the response to increasing flood losses in the country between 1998 and 2008, the State Hydrometeorological Service of Ukraine, which is subordinate to the Ministry of Emergencies, in the cooperation with the National Academy of Sciences of Ukraine have carried out the research study focusing on public views on the problem of river floods for Ukraine. Aims of this study were: a) exploring the main sources of information on water-related hazards and the level of knowledge useful in a flood crisis situation in different groups of peoples; b) learning what the various population groups think of the most significant causes and consequences of flood damages and the role of various central/governmental/ and local authorities in an elaboration and implementation of mitigation measures. Public attitudes towards various prevention and mitigation strategies, as well as sources of emerging conflict were also revealed. The results of study have given a possibility to compare points of view of population groups which: a) living in the low- and high- flood risk areas; b) living in the urban and rural areas; c) having the different levels of education. The responses from 2550 residents have been analyzed and summarized. Among the most important findings of this study can be indicated following: a) on the one hand, the level of knowledge of some aspects of flood problem (impact of climate variation and change, adaptation measures) of the general public should be improved, on the other hand, the most of peoples understand that floods are the significant economical and ecological problem; b) views of the public on the problem differ very much with regard

  13. Flood hazard mapping by integrating airborne laser scanning data, high resolution images and large scale maps: a case study

    OpenAIRE

    Fernandez, P.; G. Gonçalves; Gomes Pereira, L.; Moreira, M.

    2012-01-01

    The assessment and management of flood risks framework impose the mapping of flood hazard in potential flood risks areas. Floods in urban environments may happen due to rainfall extreme events and be exacerbated by saturated or impervious surfaces. Flood risk is greater in urban areas. (...)

  14. Impact of a flood disaster on sediment toxicity in a major river system - the Elbe flood 2002 as a case study

    Energy Technology Data Exchange (ETDEWEB)

    Oetken, Matthias [Johann Wolfgang Goethe University Frankfurt am Main, Department of Ecology and Evolution, Siesmayerstrasse 70, D-60054 Frankfurt (Germany)]. E-mail: oetken@zoology.uni-frankfurt.de; Stachel, Burkhard [Wasserguetestelle Elbe der Arbeitsgemeinschaft fuer die Reinhaltung der Elbe, Nessdeich 120-121, D-21129 Hamburg (Germany); Pfenninger, Markus [Johann Wolfgang Goethe University Frankfurt am Main, Department of Ecology and Evolution, Siesmayerstrasse 70, D-60054 Frankfurt (Germany); Oehlmann, Joerg [Johann Wolfgang Goethe University Frankfurt am Main, Department of Ecology and Evolution, Siesmayerstrasse 70, D-60054 Frankfurt (Germany)

    2005-03-01

    The ecotoxicological implications of a flooding disaster were investigated with the exceptional Elbe flood in August 2002 as an example. Sediment samples were taken shortly after the flood at 37 sites. For toxicity assessment the midge Chironomus riparius (Insecta) and the mudsnail Potamopyrgus antipodarum (Gastropoda) were exposed to the sediment samples for 28 days. For a subset of 19 sampling sites, the contamination level and the biological response of both species were also recorded before the flood in 2000. The direct comparison of biological responses at identical sites revealed significant differences for samples taken before and immediately after the flood. After flood sediments of the river Elbe caused both higher emergence rates in the midge and higher numbers of embryos in the mudsnail. Contrary to expectations the toxicity of the sediments decreased after the flood, probably because of a dilution of toxic substances along the river Elbe and a reduction in bioavailability of pollutants as a result of increasing TOC values after the flood. - The extraordinary Elbe flood in August 2002 did not result in an overall increase of environmental contamination.

  15. Micro-scale flood risk estimation in historic centres: a case study in Florence, Italy

    Science.gov (United States)

    Castelli, Fabio; Arrighi, Chiara; Brugioni, Marcello; Franceschini, Serena; Mazzanti, Bernardo

    2013-04-01

    The route to flood risk assessment is much more than hydraulic modelling of inundation, that is hazard mapping. Flood risk is the product of flood hazard, vulnerability and exposure, all the three to be estimated with comparable level of accuracy. While hazard maps have already been implemented in many countries, quantitative damage and risk maps are still at a preliminary level. Currently one of the main challenges in flood damage estimation resides in the scarce availability of socio-economic data characterizing the monetary value of the exposed assets. When these public-open data are available, the variability of their level of detail drives the need of merging different sources and of selecting an appropriate scale of analysis. In this work a parsimonious quasi-2D hydraulic model is adopted, having many advantages in terms of easy set-up. In order to represent the geometry of the study domain an high-resolution and up-to-date Digital Surface Model (DSM) is used. The accuracy in flood depth estimation is evaluated by comparison with marble-plate records of a historic flood in the city of Florence (Italy). The accuracy is characterized in the downtown most flooded area by a bias of a very few centimetres and a determination coefficient of 0.73. The average risk is found to be about 14 €/m2•year, corresponding to about 8.3% of residents income. The spatial distribution of estimated risk highlights a complex interaction between the flood pattern and the buildings characteristics. Proceeding through the risk estimation steps, a new micro-scale potential damage assessment method is proposed. This method is based on the georeferenced census system considered as optimal compromise between spatial detail and open availability of socio-economic data. The census sections system consist of geographically contiguous polygons that usually coincide with building blocks in dense urban areas. The results of flood risk assessment at the census section scale resolve most of

  16. Uncorrected land-use planning highlighted by flooding: the Alba case study (Piedmont, Italy)

    Science.gov (United States)

    Luino, F.; Turconi, L.; Petrea, C.; Nigrelli, G.

    2012-07-01

    Alba is a town of over 30 000 inhabitants located along the Tanaro River (Piedmont, northwestern Italy) and is famous for its wine and white truffles. Many important industries and companies are based in Alba, including the famous confectionery group Ferrero. The town suffered considerably from a flood that occurred on 5-6 November 1994. Forty-eight percent of the urban area was inundated, causing severe damage and killing nine people. After the flood, the Alba area was analysed in detail to determine the reasons for its vulnerability. Information on serious floods in this area since 1800 was gathered from official records, state technical office reports, unpublished documents in the municipal archives, and articles published in local and national newspapers. Maps, plans and aerial photographs (since 1954) were examined to reconstruct Alba's urban development over the last two centuries and the planform changes of the Tanaro River. The results were compared with the effects of the November 1994 flood, which was mapped from aerial photographs taken immediately after the flood, field surveys and eyewitness reports. The territory of Alba was subdivided into six categories: residential; public service; industrial, commercial and hotels; sports areas, utilities and standards (public gardens, parks, athletics grounds, private and public sport clubs); aggregate plants and dumps; and agriculture and riverine strip. The six categories were then grouped into three classes with different flooding-vulnerability levels according to various parameters. Using GIS, the three river corridors along the Tanaro identified by the Autorità di Bacino del Fiume Po were overlaid on the three classes to produce a final map of the risk areas. This study shows that the historic floods and their dynamics have not been duly considered in the land-use planning of Alba. The zones that were most heavily damaged in the 1994 flood were those that were frequently affected in the past and sites of

  17. Uncorrected land-use planning highlighted by flooding: the Alba case study (Piedmont, Italy

    Directory of Open Access Journals (Sweden)

    F. Luino

    2012-07-01

    Full Text Available Alba is a town of over 30 000 inhabitants located along the Tanaro River (Piedmont, northwestern Italy and is famous for its wine and white truffles. Many important industries and companies are based in Alba, including the famous confectionery group Ferrero.

    The town suffered considerably from a flood that occurred on 5–6 November 1994. Forty-eight percent of the urban area was inundated, causing severe damage and killing nine people. After the flood, the Alba area was analysed in detail to determine the reasons for its vulnerability.

    Information on serious floods in this area since 1800 was gathered from official records, state technical office reports, unpublished documents in the municipal archives, and articles published in local and national newspapers. Maps, plans and aerial photographs (since 1954 were examined to reconstruct Alba's urban development over the last two centuries and the planform changes of the Tanaro River.

    The results were compared with the effects of the November 1994 flood, which was mapped from aerial photographs taken immediately after the flood, field surveys and eyewitness reports.

    The territory of Alba was subdivided into six categories: residential; public service; industrial, commercial and hotels; sports areas, utilities and standards (public gardens, parks, athletics grounds, private and public sport clubs; aggregate plants and dumps; and agriculture and riverine strip. The six categories were then grouped into three classes with different flooding-vulnerability levels according to various parameters. Using GIS, the three river corridors along the Tanaro identified by the Autorità di Bacino del Fiume Po were overlaid on the three classes to produce a final map of the risk areas.

    This study shows that the historic floods and their dynamics have not been duly considered in the land-use planning of Alba. The zones that were most heavily damaged in the 1994 flood were

  18. Impact of a flood disaster on sediment toxicity in a major river system--the Elbe flood 2002 as a case study.

    Science.gov (United States)

    Oetken, Matthias; Stachel, Burkhard; Pfenninger, Markus; Oehlmann, Jörg

    2005-03-01

    The ecotoxicological implications of a flooding disaster were investigated with the exceptional Elbe flood in August 2002 as an example. Sediment samples were taken shortly after the flood at 37 sites. For toxicity assessment the midge Chironomus riparius (Insecta) and the mudsnail Potamopyrgus antipodarum (Gastropoda) were exposed to the sediment samples for 28 days. For a subset of 19 sampling sites, the contamination level and the biological response of both species were also recorded before the flood in 2000. The direct comparison of biological responses at identical sites revealed significant differences for samples taken before and immediately after the flood. After flood sediments of the river Elbe caused both higher emergence rates in the midge and higher numbers of embryos in the mudsnail. Contrary to expectations the toxicity of the sediments decreased after the flood, probably because of a dilution of toxic substances along the river Elbe and a reduction in bioavailability of pollutants as a result of increasing TOC values after the flood.

  19. Neural network modeling and geochemical water analyses to understand and forecast karst and non-karst part of flash floods (case study on the Lez river, Southern France)

    Science.gov (United States)

    Darras, T.; Raynaud, F.; Borrell Estupina, V.; Kong-A-Siou, L.; Van-Exter, S.; Vayssade, B.; Johannet, A.; Pistre, S.

    2015-06-01

    Flash floods forecasting in the Mediterranean area is a major economic and societal issue. Specifically, considering karst basins, heterogeneous structure and nonlinear behaviour make the flash flood forecasting very difficult. In this context, this work proposes a methodology to estimate the contribution from karst and non-karst components using toolbox including neural networks and various hydrological methods. The chosen case study is the flash flooding of the Lez river, known for his complex behaviour and huge stakes, at the gauge station of Lavallette, upstream of Montpellier (400 000 inhabitants). After application of the proposed methodology, discharge at the station of Lavallette is spited between hydrographs of karst flood and surface runoff, for the two events of 2014. Generalizing the method to future events will allow designing forecasting models specifically for karst and surface flood increasing by this way the reliability of the forecasts.

  20. Spatial Multicriteria Decision Analysis of Flood Risks in Aging-Dam Management in China: A Framework and Case Study

    Directory of Open Access Journals (Sweden)

    Jinbao Sheng

    2011-05-01

    Full Text Available Approximately 30,000 dams in China are aging and are considered to be high-level risks. Developing a framework for analyzing spatial multicriteria flood risk is crucial to ranking management scenarios for these dams, especially in densely populated areas. Based on the theories of spatial multicriteria decision analysis, this report generalizes a framework consisting of scenario definition, problem structuring, criteria construction, spatial quantification of criteria, criteria weighting, decision rules, sensitivity analyses, and scenario appraisal. The framework is presented in detail by using a case study to rank dam rehabilitation, decommissioning and existing-condition scenarios. The results show that there was a serious inundation, and that a dam rehabilitation scenario could reduce the multicriteria flood risk by 0.25 in the most affected areas; this indicates a mean risk decrease of less than 23%. Although increased risk (

  1. Building Development Practice in Flood Prone Area: Case of Ogbaru Council Area of Anambra State Nigeria

    Directory of Open Access Journals (Sweden)

    Peter Uchenna Okoye

    2015-08-01

    Full Text Available This study examined the practice of building development in flood prone areas and how it has contributed to the menace of flooding in Ogbaru Council Area of Anambra State Nigeria. It was a survey research where questionnaires were distributed to heads of the selected households, in addition to physical observations on buildings within the selected households. Four towns out of sixteen towns that made up Ogbaru Council Area of Anambra State were purposefully selected. From these towns, 96 households each were randomly selected and a total of 384 questionnaires were administered to the head of each household or their representative, whereas 242 copies were completed, returned and found useful, thus, giving a response rate of 62.92%. The study found that siting of buildings on waterways, flood channels/plains, inadequate/lack of drains in the compounds, lack of planning restriction/developmental control, size of the building/area occupied by the building among others contribute greatly to the incessant flood menace in the study area. The study therefore deduced that some building practices such as those identified above have the ability of exacerbating the velocity and rate of flooding in the area which turned into natural disaster, and thus, recommended strict enforcement of building and urban development laws and control in the state to reduce indiscriminate erecting of building structures on waterways, including planlessness of our emerging urban centres.

  2. Estimating Flood Quantiles on the Basis of Multi-Event Rainfall Simulation – Case Study

    Directory of Open Access Journals (Sweden)

    Jarosińska Elżbieta

    2015-12-01

    Full Text Available This paper presents an approach to estimating the probability distribution of annual discharges Q based on rainfall-runoff modelling using multiple rainfall events. The approach is based on the prior knowledge about the probability distribution of annual maximum daily totals of rainfall P in a natural catchment, random disaggregation of the totals into hourly values, and rainfall-runoff modelling. The presented Multi-Event Simulation of Extreme Flood method (MESEF combines design event method based on single-rainfall event modelling, and continuous simulation method used for estimating the maximum discharges of a given exceedance probability using rainfall-runoff models. In the paper, the flood quantiles were estimated using the MESEF method, and then compared to the flood quantiles estimated using classical statistical method based on observed data.

  3. Climate change impact assessment of extreme precipitation on urban flash floodscase study, Aarhus, Denmark

    DEFF Research Database (Denmark)

    Madsen, Henrik; Sunyer Pinya, Maria Antonia; Rosbjerg, Dan

    Climate change is expected to cause more intense extreme rainfall events, which will have a severe impact on the risk of flash floods in urban areas. An assessment study was performed for the city of Aarhus, Denmark, analysing different methods of statistical downscaling of climate model projecti......Climate change is expected to cause more intense extreme rainfall events, which will have a severe impact on the risk of flash floods in urban areas. An assessment study was performed for the city of Aarhus, Denmark, analysing different methods of statistical downscaling of climate model...... considered. Urban flooding in Aarhus was simulated with a model that dynamically couples a hydraulic model of the drainage system and a 2D overland flow model. Scenarios representing current and future climate including uncertainties in the climate projections were analysed using synthetic design storms...

  4. Joint impact of rainfall and tidal level on flood risk in a coastal city with a complex river network: a case study for Fuzhou city, China

    Directory of Open Access Journals (Sweden)

    J. J. Lian

    2012-06-01

    Full Text Available Coastal cities are particularly vulnerable to flood under the combined effect of multivariable variables, such as heavy rainfall, high sea level and large waves. For better assessment and management of flood risk the combined effect and joint probability should be considered. This paper aims to study the joint impact of rainfall and tidal level on flood risk by estimating the combined risk degree of flood and the joint flood probability. The area of case study is a typical coastal city in China, which has a complex river system. The flood in this city is mainly caused by inundation of river system. In this paper, the combined risk degree of flood is assessed by analyzing the behavior of the complex river network of the city under the combined effect of rainfall and tidal level with diverse return periods. The hydraulic model of the complex drainage network is established using HEC-RAS and verified by comparing the simulation results with the observed data during Typhoon "Longwang". The joint distribution and combined risk probability of rainfall and tidal level are estimated using the optimal copula function. The work carried out in this paper would facilitate assessment of flood risk significantly, which can be referred for the similar cities.

  5. Prevalence of enteroaggregative Escherichia coli and its virulence-related genes in a case-control study among children from north-eastern Brazil.

    Science.gov (United States)

    Lima, Ila Fernanda Nunes; Boisen, Nadia; Quetz, Josiane da Silva; Havt, Alexandre; de Carvalho, Eunice Bobo; Soares, Alberto Melo; Lima, Noélia Leal; Mota, Rosa Maria Salani; Nataro, James P; Guerrant, Richard Littleton; Lima, Aldo Ângelo Moreira

    2013-05-01

    Enteroaggregative Escherichia coli (EAEC) is an important agent that causes endemic and epidemic diarrhoeal diseases worldwide. Several EAEC virulence-related genes (VRGs) have been described but their role in the clinical outcome of infection is not completely defined. This study investigated the prevalence of EAEC and potential associations of its VRGs with risk of or protection from diarrhoeal diseases in children from urban communities in north-eastern Brazil. The case-control study included 166 children, who had their stools evaluated for the EAEC diagnostic genes (aaiC and aatA) using PCR. Positive samples were further analysed by multiplex PCR and identified 18 VRGs. EAEC was found in the same proportion in both groups (41%). The plasmid-borne gene encoding a hexosyltransferase homologue (capU) was the most frequently detected (89.6%), followed by dispersin protein (aap, 58.2%) and EAEC HilA homologue (eilA, 57.8%). The AAF/III fimbrial subunit (agg3A) gene was observed at lower frequency (1.5%). Plasmid-encoded toxin (pet) or AAF/II fimbrial subunit (aafA) was associated significantly with disease. AAF/IV fimbrial subunit (agg4A) or hypothetical plasmid-encoded haemolysin (orf61) was detected significantly more in controls than in children with diarrhoea. In addition, one set of genes in combination, aaiC and agg3/4C but lacking agg4A and orf61, was associated with diarrhoea cases; and another one, orf61 in the absence of pet and aafA, was correlated with control children. These data confirm a high prevalence, endemicity and heterogeneity of EAEC strains in the developing urban areas of north-eastern Brazil. Statistical correlation between cases and controls was seen with either isolated or combined sets of genes, suggesting that the pathophysiology of EAEC infection involves a complex and dynamic modulation of several VRGs.

  6. Seasonal patterns for entomological measures of risk for exposure to Culex vectors and West Nile virus in relation to human disease cases in northeastern Colorado.

    Science.gov (United States)

    Bolling, Bethany G; Barker, Christopher M; Moore, Chester G; Pape, W John; Eisen, Lars

    2009-11-01

    We examined seasonal patterns for entomological measures of risk for exposure to Culex vectors and West Nile virus (family Flaviviridae, genus Flavivirus, WNV) in relation to human WNV disease cases in a five-county area of northeastern Colorado during 2006-2007. Studies along habitat/elevation gradients in 2006 showed that the seasonal activity period is shortened and peak numbers occur later in the summer for Culex tarsalis Coquillett females in foothills-montane areas >1600 m compared with plains areas Studies in the plains of northeastern Colorado in 2007 showed that seasonal patterns of abundance for Cx. tarsalis and Culex pipiens L. females differed in that Cx. tarsalis reached peak abundance in early July (mean of 328.9 females per trap night for 18 plains sites), whereas the peak for Cx. pipiens did not occur until late August (mean of 16.4 females per trap night). During June-September in 2007, which was a year of intense WNV activity in Colorado with 578 reported WNV disease cases, we recorded WNV-infected Cx. tarsalis females from 16 of 18 sites in the plains. WNV infection rates in Cx. tarsalis females increased gradually from late June to peak in mid-August (overall maximum likelihood estimate for WNV infection rate of 8.29 per 1000 females for the plains sites in mid-August). No WNV-infected Culex mosquitoes were recorded from sites >1600 m. The vector index for abundance of WNV-infected Cx. tarsalis females for the plains sites combined exceeded 0.50 from mid-July to mid-August, with at least one site exceeding 1.00 from early July to late August. Finally, we found that abundance of Cx. tarsalis females and the vector index for infected females were strongly associated with weekly numbers of WNV disease cases with onset 4-7 wk later (female abundance) or 1-2 wk later (vector index).

  7. Flood probability quantification for road infrastructure: Data-driven spatial-statistical approach and case study applications.

    Science.gov (United States)

    Kalantari, Zahra; Cavalli, Marco; Cantone, Carolina; Crema, Stefano; Destouni, Georgia

    2017-03-01

    Climate-driven increase in the frequency of extreme hydrological events is expected to impose greater strain on the built environment and major transport infrastructure, such as roads and railways. This study develops a data-driven spatial-statistical approach to quantifying and mapping the probability of flooding at critical road-stream intersection locations, where water flow and sediment transport may accumulate and cause serious road damage. The approach is based on novel integration of key watershed and road characteristics, including also measures of sediment connectivity. The approach is concretely applied to and quantified for two specific study case examples in southwest Sweden, with documented road flooding effects of recorded extreme rainfall. The novel contributions of this study in combining a sediment connectivity account with that of soil type, land use, spatial precipitation-runoff variability and road drainage in catchments, and in extending the connectivity measure use for different types of catchments, improve the accuracy of model results for road flood probability. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Flood risk analysis for metropolitan areas – a case study for Shanghai

    NARCIS (Netherlands)

    Ke, Q.

    2014-01-01

    In Shanghai, the main threat to the city’s safety is a typhoon induced storm surge in combination with a high astronomic tide in the Huangpu River. Historical flood events have shown that the weakness of the floodwall, with potential overtopping and breaching along the Huangpu River and its branches

  9. Risk of flooding: Activities, parameters and regional peculiarities, Case study: Varbitsa watershed basin, Bulgaria

    Directory of Open Access Journals (Sweden)

    Lubenov Todor

    2009-01-01

    Full Text Available An overview of the activities overtaken during risk of flooding situations, in one of the more often flooding region - the watershed of Varbitsa river (Southeastern part of Bulgaria - has been performed. The main cognitive parameters for risk perception and risk definition, depending on regional, social and historical factors have been examined. The existing information and instructions for mass media communication in relation to the process of interaction in a disaster situation have been discussed. In connection to determination of the risky segments in the basin and plans for announcement, the prevention communication measures have been outlined. On the basis of the Bulgarian normative legislation, the activities concerning organization of communications in a risk-of-disaster situation and mutual aid between authorities, which are part of the Integrated Help System have been indicated. It has been accented on the necessity of a more effective realization of the action plans during natural disasters and especially flooding, in order to improve the partnership between authorities and participants in the communication process during risk-of-flooding situations.

  10. Flooding and Health Care Visits for Clostridium Difficile Infection: A Case-Crossover Analysis

    Science.gov (United States)

    Floods can contaminate potable water and other resources, thus increasing the potential for fecal-oral transmission of pathogens. Clostridium difficile is a bacterium that can spread by water and cause acute gastrointestinal illness. It often affects older adults who are hospital...

  11. Assessing quick wins to protect critical urban infrastructure from floods: a case study in Bangkok, Thailand.

    NARCIS (Netherlands)

    Zevenbergen, Chris; Herk, S. van; Escarameia, M.; Gersonius, B.; Serre, D.; Walliman, N.; Bruijn, K.M. de; Graaf, Rutger de

    2015-01-01

    This paper focuses on the vulnerability and protection of critical urban infrastructure from flooding. It presents a pragmatic and rapid screening procedure, referred to as a ‘Quick Scan methodology’. The purpose of the Quick Scan is to provide guidance for network operators and decision makers on i

  12. Flood risk analysis for metropolitan areas – a case study for Shanghai

    NARCIS (Netherlands)

    Ke, Q.

    2014-01-01

    In Shanghai, the main threat to the city’s safety is a typhoon induced storm surge in combination with a high astronomic tide in the Huangpu River. Historical flood events have shown that the weakness of the floodwall, with potential overtopping and breaching along the Huangpu River and its

  13. Flooding and Health Care Visits for Clostridium Difficile Infection: A Case-Crossover Analysis

    Science.gov (United States)

    Floods can contaminate potable water and other resources, thus increasing the potential for fecal-oral transmission of pathogens. Clostridium difficile is a bacterium that can spread by water and cause acute gastrointestinal illness. It often affects older adults who are hospital...

  14. Flash flood forecasting in poorly gauged basins using neural networks: case study of the Gardon de Mialet basin (southern France

    Directory of Open Access Journals (Sweden)

    G. Artigue

    2012-11-01

    Full Text Available In southern France, flash flood episodes frequently cause fatalities and severe damage. In order to inform and warn populations, the French flood forecasting service (SCHAPI, Service Central d'Hydrométéorologie et d'Appui à la Prévision des Inondations initiated the BVNE (Bassin Versant Numérique Expérimental, or Experimental Digital Basin project in an effort to enhance flash flood predictability. The target area for this study is the Gardon d'Anduze basin, located in the heart of the Cévennes range. In this Mediterranean mountainous setting, rainfall intensity can be very high, resulting in flash flooding. Discharge and rainfall gauges are often exposed to extreme weather conditions, which undermines measurement accuracy and continuity. Moreover, the processes governing rainfall-discharge relations are not well understood for these steeply-sloped and heterogeneous basins. In this context of inadequate information on both the forcing variables and process knowledge, neural networks are investigated due to their universal approximation and parsimony properties. We demonstrate herein that thanks to a rigorous variable and complexity selection, efficient forecasting of up to two-hour durations, without requiring rainfall forecasting as input, can be derived using the measured discharges available from a feedforward model. In the case of discharge gauge malfunction, in degraded mode, forecasting may result using a recurrent neural network model. We also observe that neural network models exhibit low sensitivity to uncertainty in rainfall measurements since producing ensemble forecasting does not significantly affect forecasting quality. In providing good results, this study suggests close consideration of our main purpose: generating forecasting on ungauged basins.

  15. Intercomparison of regional flood frequency estimation methods at ungauged sites for a Mexican case study

    Science.gov (United States)

    Ouarda, T. B. M. J.; Bâ, K. M.; Diaz-Delgado, C.; Cârsteanu, A.; Chokmani, K.; Gingras, H.; Quentin, E.; Trujillo, E.; Bobée, B.

    2008-01-01

    SummaryThis paper presents an adaptation of some regional estimation approaches to tropical climates and a comparison of their performance on the basis of their application to data from the Balsas, Lerma and Pánuco River Basins located in Mexico. Four approaches are used in this study for the delineation of homogeneous regions: The first one is the hierarchical cluster analysis approach which leads to fixed hydrologic regions. The second one is the canonical correlation analysis (CCA) which allows the determination of hydrologic neighborhoods that are specific to the site of interest. The third one is a revised version of the canonical correlation analysis approach that is free of parameter optimization and which can be automated easily. Finally, the fourth one is the technique of canonical kriging which consists in interpolating hydrological variables over the canonical physiographical space. The methods based on the canonical correlation analysis approach provide also the basis for identifying the explanatory variables to be used during the step of regional estimation. Regional estimation is carried out based on a multiple regression approach. A data set of 29 stations from several Mexican River Basins in and around the Balsas region is used to show the advantages and weaknesses of each method and to demonstrate their usefulness in the context of regional flood quantile estimation. This study allows also to test the robustness of these methods through their application to a real world case study with a relatively limited number of stations. While all methods performed quite adequately, results indicate clearly the advantages of the neighborhood type of approach and the superiority of the canonical correlation analysis based methods. Results demonstrate that CCA-based methods lead to best performances overall. While hierarchical clustering seems generally to lead to less biased quantile estimates, the lowest root mean square error values are almost consistently

  16. Evaluation on Soil Heavy Metal Pollution around Tailing Areas: A Case Study of Ag-Sb Deposit in Northeastern Guangdong

    Institute of Scientific and Technical Information of China (English)

    Deliang; LIU; Kaifeng; WANG; Qihe; YANG; Qin; Zhu

    2015-01-01

    In October 2012,an evaluation using potential ecological hazard risk index was carried out on soil heavy metal pollution around AgSb deposit tailing areas in northeastern Guangdong. Results indicate that( i) soil heavy metal pollution is mainly Cd-Ni compound pollution,including Cd content 0. 31- 2. 66 mg / kg( average content is 1. 11 mg / kg),the situation of exceeding standard is serious( the rate of exceeding standard is 100%); the total potential ecological hazard risk index( RI) is between 50 and 300,and it is moderate pollution;( ii) in soil heavy metal content,only Ni and Cu are positively correlated. Since there is certain degree of Ni pollution in this deposit,the synergetic effect of Cu and Ni may deteriorate Ni pollution.

  17. The added value of system robustness analysis for flood risk management illustrated by a case on the IJssel River

    OpenAIRE

    M. J. P. Mens; Klijn, F.

    2015-01-01

    Decision makers in fluvial flood risk management increasingly acknowledge that they have to prepare for extreme events. Flood risk is the most common basis on which to compare flood risk-reducing strategies. To take uncertainties into account the criteria of robustness and flexibility are advocated as well. This paper discusses the added value of robustness as an additional decision criterion compared to single-value flood risk only. We do so by quantifying flood risk and sy...

  18. [Effect of flooding disturbance on aboveground biomass of Leymus chinensis grassland--a preliminary study].

    Science.gov (United States)

    Wang, Zhengwen; Zhu, Tingcheng

    2003-12-01

    To investigate the effect of flooding disturbance on the net primary productivity of Songnen steppe, a comparatively thorough study was conducted on Sanjiadian State-owned Rangeland in Da'an city, Jilin Province, which was partly flooded in 1998. The study site was located in the south Songnen plain of Northeastern China, dominated by Leymus chinensis grassland. An extensively mild slope with flooding gradients (from un-flooded to heavily flooded) was taken as the study site. Two flooded transects coded FL and FH which was respectively subjected to 3 and 9 months of flooding were designed, and an un-flooded one coded CK at a relatively higher elevation was set as a control. Before flooding occurred in 1998, the slope had an almost uniform soil and L. chinensis dominated vegetation. Each transect was 0.2 hm2 (100 m x 20 m) in size, and the two flooded transects were almost paralleled each other, with the longer sides of them perpendicular to the retrieving direction of floodwater. In each transect twenty 1 m2 sized quadrats were randomly chosen to survey the community structure and the aboveground biomass. Comparative analyses were made on the dynamics of soil water, soil N and P, and species composition of grassland communities that occurred in responses to flooding disturbance. The results showed that the lightly and heavily flooded transects had a significantly larger aboveground biomass than the control, with the increase of 89.54% and 113.45%, respectively. The heavily flooded transect had a slightly but insignificantly larger aboveground biomass than the lightly flooded one, indicating that on flooded sites, water was not the limiting factor of the aboveground biomass. The acute changes of soil water caused by flooding led to the changes of soil nutrients and species assemblages, which would impact community biomass. Just as the case for aboveground biomass, the soil water contents of the two flooded transects were significantly larger than that of control

  19. Gender disparities in flood risk perception and preparedness: a Serbian case study

    Science.gov (United States)

    Cvetković, Vladimir M.; Roder, Giulia; Tarolli, Paolo; Öcal, Adem; Ronan, Kevin; Dragićević, Slavoljub

    2017-04-01

    The catastrophic flood occurred in Serbia in 2014 was one of the most critical events registered in the Balkan area in the last decades. The procedures for evacuation have been tough to manage indicating a low level of perception and preparedness towards flood events. Also, the failure in the response phase showed a gender unbalance, where information did not reach men and women equally. Urgently, the Council for Gender Equality Government of the Republic of Serbia held an extraordinary meeting dedicated to the flood planning and emergency support in a gendered perspective. It concluded with the necessity of developing more gender-sensitive statistics, indicators of vulnerability, reconstruction and recovery to floods. For these reasons, we conducted an extensive interview to underlined the differences in risk perception and preparedness actions of both women and men regarding flood events in Serbia. 2500 face-to-face interviews have been conducted in 27 out of 150 municipalities being a good representative sample of the country with the use of a multi-stage random sample. The research findings indicated that is a gender disparity among men and women both in the perception than in the preparedness actions toward floods. Men seemed to be more confident in their abilities to cope with flooding, assessing a greater individual and household preparedness. This could be ascribable to their active involvement in the army where young men were educated to manage emergency situations. They displayed more trust in themselves rather than external agencies or organisation, and this could result in a general mistrust on institutions and planned evacuations. On the other hand, women displayed larger sensitivity and knowledge to these events, however, this did not translate into a capacity to react. It has been assumed that their work as child-carers and housekeepers made them unable to create a strong social network within the community being less informed and involved in the

  20. Rainfall downscaling and flood forecasting: a case study in the Mediterranean area

    Directory of Open Access Journals (Sweden)

    N. Rebora

    2006-01-01

    Full Text Available The prediction of the small-scale spatial-temporal pattern of intense rainfall events is crucial for flood risk assessment in small catchments and urban areas. In the absence of a full deterministic modelling of small-scale rainfall, it is common practice to resort to the use of stochastic downscaling models to generate ensemble rainfall predictions to be used as inputs to rainfall-runoff models. In this work we present an application of a new spatial-temporal downscaling procedure, called RainFARM, to an intense precipitation event predicted by the limited-area meteorological model Lokal Model over north-west Italy. The uncertainty in flood prediction associated with the small unresolved scales of forecasted precipitation fields is evaluated by using an ensemble of downscaled fields to drive a semi-distributed rainfall-runoff model.

  1. Multi-decadal Hydrological Retrospective: Case study of Amazon floods and droughts

    Science.gov (United States)

    Wongchuig Correa, Sly; Paiva, Rodrigo Cauduro Dias de; Espinoza, Jhan Carlo; Collischonn, Walter

    2017-06-01

    Recently developed methodologies such as climate reanalysis make it possible to create a historical record of climate systems. This paper proposes a methodology called Hydrological Retrospective (HR), which essentially simulates large rainfall datasets, using this as input into hydrological models to develop a record of past hydrology, making it possible to analyze past floods and droughts. We developed a methodology for the Amazon basin, where studies have shown an increase in the intensity and frequency of hydrological extreme events in recent decades. We used eight large precipitation datasets (more than 30 years) as input for a large scale hydrological and hydrodynamic model (MGB-IPH). HR products were then validated against several in situ discharge gauges controlling the main Amazon sub-basins, focusing on maximum and minimum events. For the most accurate HR, based on performance metrics, we performed a forecast skill of HR to detect floods and droughts, comparing the results with in-situ observations. A statistical temporal series trend was performed for intensity of seasonal floods and droughts in the entire Amazon basin. Results indicate that HR could represent most past extreme events well, compared with in-situ observed data, and was consistent with many events reported in literature. Because of their flow duration, some minor regional events were not reported in literature but were captured by HR. To represent past regional hydrology and seasonal hydrological extreme events, we believe it is feasible to use some large precipitation datasets such as i) climate reanalysis, which is mainly based on a land surface component, and ii) datasets based on merged products. A significant upward trend in intensity was seen in maximum annual discharge (related to floods) in western and northwestern regions and for minimum annual discharge (related to droughts) in south and central-south regions of the Amazon basin. Because of the global coverage of rainfall datasets

  2. Estimation of probability of coastal flooding: A case study in the Norton Sound, Alaska

    Science.gov (United States)

    Kim, S.; Chapman, R. S.; Jensen, R. E.; Azleton, M. T.; Eisses, K. J.

    2010-12-01

    Along the Norton Sound, Alaska, coastal communities have been exposed to flooding induced by the extra-tropical storms. Lack of observation data especially with long-term variability makes it difficult to assess the probability of coastal flooding critical in planning for development and evacuation of the coastal communities. We estimated the probability of coastal flooding with the help of an existing storm surge model using ADCIRC and a wave model using WAM for the Western Alaska which includes the Norton Sound as well as the adjacent Bering Sea and Chukchi Sea. The surface pressure and winds as well as ice coverage was analyzed and put in a gridded format with 3 hour interval over the entire Alaskan Shelf by Ocean Weather Inc. (OWI) for the period between 1985 and 2009. The OWI also analyzed the surface conditions for the storm events over the 31 year time period between 1954 and 1984. The correlation between water levels recorded by NOAA tide gage and local meteorological conditions at Nome between 1992 and 2005 suggested strong local winds with prevailing Southerly components period are good proxies for high water events. We also selected heuristically the local winds with prevailing Westerly components at Shaktoolik which locates at the eastern end of the Norton Sound provided extra selection of flood events during the continuous meteorological data record between 1985 and 2009. The frequency analyses were performed using the simulated water levels and wave heights for the 56 year time period between 1954 and 2009. Different methods of estimating return periods were compared including the method according to FEMA guideline, the extreme value statistics, and fitting to the statistical distributions such as Weibull and Gumbel. The estimates are similar as expected but with a variation.

  3. Integrated flood disaster management and spatial information: Case studies of Netherlands and India

    OpenAIRE

    S. Zlatanova; Ghawana, T.; Kaur, A.; Neuvel, J. M. M.

    2014-01-01

    Spatial Information is an integral part of flood management practices which include risk management & emergency response processes. Although risk & emergency management activities have their own characteristics, for example, related to the time scales, time pressure, activities & actors involved, it is still possible to identify at least one common challenge that constrains the ability of risk & emergency management to plan for & manage emergencies effectively and efficiently i.e. the need fo...

  4. Contribution of an exposure indicator to better anticipate damages with the AIGA flood warning method: a case study in the South of France

    Science.gov (United States)

    Saint-Martin, Clotilde; Fouchier, Catherine; Douvinet, Johnny; Javelle, Pierre; Vinet, Freddy

    2016-04-01

    On the 3rd October 2015, heavy localized precipitations have occurred in South Eastern France leading to major flash floods on the Mediterranean coast. The severity of those floods has caused 20 fatalities and important damage in almost 50 municipalities in the French administrative area of Alpes-Maritimes. The local recording rain gauges have shown how fast the event has happened: 156 mm of rain were recorded in Mandelieu-la-Napoule and 145 mm in Cannes within 2 hours. As the affected rivers are not monitored, no anticipation was possible from the authorities in charge of risk management. In this case, forecasting floods is indeed complex because of the small size of the watersheds which implies a reduced catchment response time. In order to cope with the need of issuing flood warnings on un-monitored small catchments, Irstea and Météo-France have developed an alternative warning system for ungauged basins called the AIGA method. AIGA is a flood warning system based on a simple distributed hydrological model run at a 1 km² resolution using real time radar rainfall information (Javelle, Demargne, Defrance, Pansu, & Arnaud, 2014). The flood warnings, produced every 15 minutes, result of the comparison of the real time runoff data produced by the model with statistical runoff values. AIGA is running in real time in the South of France, within the RHYTMME project (https://rhytmme.irstea.fr/). Work is on-going in order to offer a similar service for the whole French territory. More than 200 impacts of the 3rd October floods have been located using media, social networks and fieldwork. The first comparisons between these impacts and the AIGA warning levels computed for this event show several discrepancies. However, these latter discrepancies appear to be explained by the land-use. An indicator of the exposure of territories to flooding has thus been created to weight the levels of the AIGA hydrological warnings with the land-use of the area surrounding the streams

  5. Ecological Responses to Extreme Flooding Events: A Case Study with a Reintroduced Bird.

    Science.gov (United States)

    Soriano-Redondo, Andrea; Bearhop, Stuart; Cleasby, Ian R; Lock, Leigh; Votier, Stephen C; Hilton, Geoff M

    2016-06-27

    In recent years numerous studies have documented the effects of a changing climate on the world's biodiversity. Although extreme weather events are predicted to increase in frequency and intensity and are challenging to organisms, there are few quantitative observations on the survival, behaviour and energy expenditure of animals during such events. We provide the first data on activity and energy expenditure of birds, Eurasian cranes Grus grus, during the winter of 2013-14, which saw the most severe floods in SW England in over 200 years. We fitted 23 cranes with telemetry devices and used remote sensing data to model flood dynamics during three consecutive winters (2012-2015). Our results show that during the acute phase of the 2013-14 floods, potential feeding areas decreased dramatically and cranes restricted their activity to a small partially unflooded area. They also increased energy expenditure (+15%) as they increased their foraging activity and reduced resting time. Survival did not decline in 2013-14, indicating that even though extreme climatic events strongly affected time-energy budgets, behavioural plasticity alleviated any potential impact on fitness. However under climate change scenarios such challenges may not be sustainable over longer periods and potentially could increase species vulnerability.

  6. Flood risk and cultural heritage: the case study of Florence (Italy)

    Science.gov (United States)

    Arrighi, Chiara; Castelli, Fabio; Brugioni, Marcello; Franceschini, Serena; Mazzanti, Bernardo

    2016-04-01

    Cultural heritage plays a key role for communities in terms of both identity and economic value. It is often under serious threat by natural hazards, nevertheless, quantitative assessments of risk are quite uncommon. This work addresses the flood risk assessment to cultural heritage in an exemplary art city, which is Florence, Italy. The risk assessment method here adopted borrows the most common definition of flood risk as the product of hazard, vulnerability and exposure, with some necessary adjustments. The risk estimation is carried out at the building scale for the whole UNESCO site, which coincides with the historical centre of the city. A distinction in macro- and micro-damage categories has been made according to the vulnerability of the objects at risk. Two damage macro-categories are selected namely cultural buildings and contents. Cultural buildings are classified in damage micro-categories as churches/religious complexes, libraries/archives and museums. The damages to the contents are estimated for four micro-categories: paintings, sculptures, books/prints and goldsmith's art. Data from hydraulic simulations for different recurrence scenarios, historical reports of the devastating 1966 flood and the cultural heritage recognition sheets allow estimating and mapping the annual expected number of works of art lost in absence of risk mitigation strategies.

  7. Flood risk assessment. Case of study: Motozintla de Mendoza, Chiapas, Mexico

    Directory of Open Access Journals (Sweden)

    David A. Novelo-Casanova

    2016-09-01

    Full Text Available Due to its geographical location, the community of Motozintla de Mendoza (Motozintla in the State of Chiapas, Mexico, is continuously exposed to the impact of natural hazards. In this work, we assessed the flood risk of Motozintla considering the structural, socioeconomic, organizational, and global (structural, socioeconomic, and organizational vulnerabilities. In addition, we also measured the local risk perception. Spatial maps were generated to determine the most vulnerable and risk areas of this community. Our results indicate that the population has a high level of risk to flooding mainly because (1 the majority of the local houses has high structural vulnerability; (2 a high percentage of the families has a daily income less than the official Mexican minimum wage and lacks of basic public services as well as of proper social security services; (3 most of the community does not know any existing Civil Protection Plan; and (4 the community organization for disaster mitigation and response is practically non-existent. For these reasons, we believe that it is necessary for local authorities to establish in the short-term, preparedness, mitigation and response plans as well as land-use measures to reduce the risk to floods in Motozintla.

  8. Variable infiltration and river flooding resulting in changing groundwater quality - A case study from Central Europe

    Science.gov (United States)

    Miotliński, Konrad; Postma, Dieke; Kowalczyk, Andrzej

    2012-01-01

    SummaryThe changes in groundwater quality occurring in a buried valley aquifer following a reduction in groundwater exploitation and enhanced infiltration due to extensive flooding of the Odra River in 1997 were investigated. Long-time series data for the chemical composition of groundwater in a large well field for drinking water supply indicated the deterioration of groundwater quality in the wells capturing water from the flooded area, which had been intensively cultivated since the 1960s. Infiltration of flooded river water into the aquifer is suggested by an elevated chloride concentration, although salt flushing from the rewatered unsaturated zone due to the enhanced recharge event is much more feasible. Concomitantly with chloride increases in the concentrations of sulphate, ferrous iron, manganese, and nickel imply the oxidation of pyrite (FeS 2) which is abundant in the aquifer. The proton production resulting from pyrite oxidation is buffered by the dissolution of calcite, while the Ca:SO 4 stoichiometry of the groundwater indicates that pyrite oxidation coupled with nitrate reduction is the dominant process occurring in the aquifer. The pyritic origin of SO42- is confirmed by the sulphur isotopic composition. The resultant Fe 2+ increase induces Mn-oxide dissolution and the mobilisation of Ni 2+ previously adsorbed to Mn-oxide surfaces. The study has a major implication for groundwater quality prediction studies where there are considerable variations in water level associated with groundwater management and climate change issues.

  9. Levee reliability analyses for various flood return periods – a case study in Southern Taiwan

    Directory of Open Access Journals (Sweden)

    W.-C. Huang

    2015-01-01

    Full Text Available In recent years, heavy rainfall conditions have caused damages around the world. To prevent damages by floods, levees have often been constructed in prone-to-inundation areas. This study performed reliability analyses for the Chiuliao 1st Levee located in southern Taiwan. The failure-related parameters were the water level, the scouring depth, and the in-situ friction angle. Three major failure mechanisms were considered, including the slope sliding failure of the levee, and the sliding and overturning failures of the retaining wall. When the variabilities of the in-situ friction angle and the scouring depth are considered for various flood return periods, the variations of the factor of safety (FS for the different failure mechanisms show that the retaining wall sliding and overturning failures are more sensitive to the variability of the friction angle. When the flood return period is greater than 2 years, the levee can undergo slope sliding failure for all values of the water level difference. The results for levee stability analysis considering the variability of different parameters could assist engineers in designing the levee cross sections, especially with potential failure mechanisms in mind.

  10. Flow monitoring with a camera: a case study on a flood event in the Tiber River.

    Science.gov (United States)

    Tauro, F; Olivieri, G; Petroselli, A; Porfiri, M; Grimaldi, S

    2016-02-01

    Monitoring surface water velocity during flood events is a challenging task. Techniques based on deploying instruments in the flow are often unfeasible due to high velocity and abundant sediment transport. A low-cost and versatile technology that provides continuous and automatic observations is still not available. Among remote methods, large-scale particle image velocimetry (LSPIV) is an optical method that computes surface water velocity maps from videos recorded with a camera. Here, we implement and critically analyze findings obtained from a recently introduced LSPIV experimental configuration during a flood event in the Tiber River at a cross section located in the center of Rome, Italy. We discuss the potential of LSPIV observations in challenging environmental conditions by presenting results from three tests performed during the hydrograph flood peak and recession limb of the event for different illumination and weather conditions. The obtained surface velocity maps are compared to the rating curve velocity and to benchmark velocity values. Experimental findings show that optical methods should be preferred in extreme conditions. However, their practical implementation may be associated with further hurdles and uncertainties.

  11. A Summary Case Report on the Health Impacts and Response to the Pakistan Floods of 2010

    Science.gov (United States)

    Shabir, Omar

    2013-01-01

    In July 2010, Pakistan suffered nationwide floods after unprecedented monsoon rains overwhelmed the Indus basin. The ensuing floods claimed 1985 lives, injured 2946 people and affected over 20.2 million people. Seventy-eight out of 121 districts were affected and at one stage one-fifth of the country’s land was inundated with water. Indiscriminate damage was caused to housing, educational and health facilities, communication networks, power plants and grids, irrigation channels, agricultural land and livestock. Over 37 million medical consultations were reported within one year of the floods with acute respiratory infection, skin diseases, acute diarrhoea and suspected malaria forming the most common presentations. Rescue and relief operations were organised through the National Disaster Management Authority and a UN Cluster Approach was adopted for providing humanitarian assistance. The Office for the Coordination of Humanitarian Affairs (OCHA) played a pivotal role in coordinating relief efforts between cluster groups and providing communication platforms for identifying gaps and sharing information. This paper attempts to collate information available in the public domain into a summary report based on key principles described by Kulling et al. (2010) on health crisis reporting. PMID:23591385

  12. Improving Global Flood Forecasting using Satellite Detected Flood Extent

    NARCIS (Netherlands)

    Revilla Romero, B.

    2016-01-01

    Flooding is a natural global phenomenon but in many cases is exacerbated by human activity. Although flooding generally affects humans in a negative way, bringing death, suffering, and economic impacts, it also has potentially beneficial effects. Early flood warning and forecasting systems, as well

  13. Improving Global Flood Forecasting using Satellite Detected Flood Extent

    NARCIS (Netherlands)

    Revilla Romero, B.

    2016-01-01

    Flooding is a natural global phenomenon but in many cases is exacerbated by human activity. Although flooding generally affects humans in a negative way, bringing death, suffering, and economic impacts, it also has potentially beneficial effects. Early flood warning and forecasting systems, as well

  14. RASOR flood modelling

    Science.gov (United States)

    Beckers, Joost; Buckman, Lora; Bachmann, Daniel; Visser, Martijn; Tollenaar, Daniel; Vatvani, Deepak; Kramer, Nienke; Goorden, Neeltje

    2015-04-01

    Decision making in disaster management requires fast access to reliable and relevant information. We believe that online information and services will become increasingly important in disaster management. Within the EU FP7 project RASOR (Rapid Risk Assessment and Spatialisation of Risk) an online platform is being developed for rapid multi-hazard risk analyses to support disaster management anywhere in the world. The platform will provide access to a plethora of GIS data that are relevant to risk assessment. It will also enable the user to run numerical flood models to simulate historical and newly defined flooding scenarios. The results of these models are maps of flood extent, flood depths and flow velocities. The RASOR platform will enable to overlay historical event flood maps with observations and Earth Observation (EO) imagery to fill in gaps and assess the accuracy of the flood models. New flooding scenarios can be defined by the user and simulated to investigate the potential impact of future floods. A series of flood models have been developed within RASOR for selected case study areas around the globe that are subject to very different flood hazards: • The city of Bandung in Indonesia, which is prone to fluvial flooding induced by heavy rainfall. The flood hazard is exacerbated by land subsidence. • The port of Cilacap on the south coast of Java, subject to tsunami hazard from submarine earthquakes in the Sunda trench. • The area south of city of Rotterdam in the Netherlands, prone to coastal and/or riverine flooding. • The island of Santorini in Greece, which is subject to tsunamis induced by landslides. Flood models have been developed for each of these case studies using mostly EO data, augmented by local data where necessary. Particular use was made of the new TanDEM-X (TerraSAR-X add-on for Digital Elevation Measurement) product from the German Aerospace centre (DLR) and EADS Astrium. The presentation will describe the flood models and the

  15. Linking Earth Observations and Models to Societal Information Needs: The Case of Coastal Flooding

    Science.gov (United States)

    Buzzanga, B. A.; Plag, H. P.

    2016-12-01

    Coastal flooding is expected to increase in many areas due to sea level rise (SLR). Many societal applications such as emergency planning and designing public services depend on information on how the flooding spectrum may change as a result of SLR. To identify the societal information needs a conceptual model is needed that identifies the key stakeholders, applications, and information and observation needs. In the context of the development of the Global Earth Observation System of Systems (GEOSS), which is implemented by the Group on Earth Observations (GEO), the Socio-Economic and Environmental Information Needs Knowledge Base (SEE-IN KB) is developed as part of the GEOSS Knowledge Base. A core function of the SEE-IN KB is to facilitate the linkage of societal information needs to observations, models, information and knowledge. To achieve this, the SEE-IN KB collects information on objects such as user types, observational requirements, societal goals, models, and datasets. Comprehensive information concerning the interconnections between instances of these objects is used to capture the connectivity and to establish a conceptual model as a network of networks. The captured connectivity can be used in searches to allow users to discover products and services for their information needs, and providers to search for users and applications benefiting from their products. It also allows to answer "What if?" questions and supports knowledge creation. We have used the SEE-IN KB to develop a conceptual model capturing the stakeholders in coastal flooding and their information needs, and to link these elements to objects. We show how the knowledge base enables the transition of scientific data to useable information by connecting individuals such as city managers to flood maps. Within the knowledge base, these same users can request information that improves their ability to make specific planning decisions. These needs are linked to entities within research

  16. Hydrological Retrospective of floods and droughts: Case study in the Amazon

    Science.gov (United States)

    Wongchuig Correa, Sly; Cauduro Dias de Paiva, Rodrigo; Carlo Espinoza Villar, Jhan; Collischonn, Walter

    2017-04-01

    Recent studies have reported an increase in intensity and frequency of hydrological extreme events in many regions of the Amazon basin over last decades, these events such as seasonal floods and droughts have originated a significant impact in human and natural systems. Recently, methodologies such as climatic reanalysis are being developed in order to create a coherent register of climatic systems, thus taking this notion, this research efforts to produce a methodology called Hydrological Retrospective (HR), that essentially simulate large rainfall datasets over hydrological models in order to develop a record over past hydrology, enabling the analysis of past floods and droughts. We developed our methodology on the Amazon basin, thus we used eight large precipitation datasets (more than 30 years) through a large scale hydrological and hydrodynamic model (MGB-IPH), after that HR products were validated against several in situ discharge gauges dispersed throughout Amazon basin, given focus in maximum and minimum events. For better HR results according performance metrics, we performed a forecast skill of HR to detect floods and droughts considering in-situ observations. Furthermore, statistical temporal series trend was performed for intensity of seasonal floods and drought in the whole Amazon basin. Results indicate that better HR represented well most past extreme events registered by in-situ observed data and also showed coherent with many events cited by literature, thus we consider viable to use some large precipitation datasets as climatic reanalysis mainly based on land surface component and datasets based in merged products for represent past regional hydrology and seasonal hydrological extreme events. On the other hand, an increase trend of intensity was realized for maximum annual discharges (related to floods) in north-western regions and for minimum annual discharges (related to drought) in central-south regions of the Amazon basin, these features were

  17. Sociocultural factors and perceptions associated with voluntary and permanent relocation of flood victims: A case study of Sekondi-Takoradi Metropolis in Ghana

    Directory of Open Access Journals (Sweden)

    Isaac Y. Addo

    2017-01-01

    Full Text Available Flooding is a major problem in many developing urban centres in Ghana, including the Sekondi-Takoradi Metropolis (STM. Residents who are living close to the Anankwari, Kansawura and Whin rivers in the metropolis often experience flooding when the rivers overflow their banks, resulting in lives being lost, people being displaced and properties being destroyed. One durable solution to the flooding problem is voluntary and permanent relocation of ‘vulnerable’ residents; but this form of solution cannot be achieved without a clear understanding of the sociocultural factors that influence the decision-making process. This study uniquely investigated the sociocultural and economic factors affecting voluntary and permanent relocation of flood victims, using Eshiem, Kansawurodo and Whindo communities as a case study. Employing a mixed cross-sectional design method, 207 heads of households were selected to fill in questionnaires; interviews were conducted with nine representatives of the traditional councils, and areas affected by flooding were photographed. The findings show that voluntary and permanent relocation was overlooked by most flood victims due to perceived inability to rent new places owing to low incomes, fear of losing income-generating ventures that serve as sources of livelihoods, hope of gaining income from the oil production within the region and the need for restitution from government before evacuation. From a sociocultural viewpoint, they felt uncomfortable with losing ancestral lands and landed properties as well as breaking long-standing ties with their community folks and other networks. Flood victims’ willingness to stay in the flood-prone communities was also influenced by duration of stay in the communities and ownership of landed assets. When considering voluntary and permanent relocation of flood victims as a durable solution in the future, these sociocultural and economic factors need to be carefully considered.

  18. An assessment of flood mitigation measures - "room for the river

    Science.gov (United States)

    Komma, J.; Blöschl, G.; Habereder, C.

    2009-04-01

    In this paper we analyse the relative effect of different flood mitigation measures for the example of the Kamp catchment in Austria. The main idea is to decrease flood peaks through (a) retaining water in the landscape and (b) providing additional inundation areas along the main stream (room for the river). To increase the retention of excess rainfall in the landscape we introduced two different measures. One measure is the increase of water storage capacity in the study catchment through the change of land use from agriculture to forest. The second measure is the installation of many small sized retention basins without an outlet (micro ponds). The micro ponds are situated at the hill slopes to intercept surface runoff. In case of the room for the river scenario the additional retention volume is gained due to the installation of retention basins along the Kamp river and its tributary Zwettl. Three flood retention basins with culverts at each river are envisaged. The geometry of the bottom outlets is defined for design discharges in a way to gain the greatest flood peak reduction for large flood events (above a 100 yr flood). The study catchment at the Kamp river with a size of 622 km² is located in north-eastern Austria. For the simulation of the different scenarios (retaining water in the landscape) a well calibrated continuous hydrologic model is available. The hydrological model consists of a spatially distributed soil moisture accounting scheme and a flood routing component. To analyse the effect of the room for the river scenario with retention basins along the river reaches a linked 1D/2D hydrodynamic model (TUFLOW) is used. In the river channels a one dimensional simulation is carried out. The flow conditions in the flood plains are represented by two dimensional model elements. The model domain incorporates 18 km of the Kamp and 12 km of the Zwettl river valley. For the assessment of the land use change scenario the hydrologic model parameters for

  19. Climate change and diverse dimensions of glacial lake outburst floods (GLOFs): Lake Palcacocha case study, Peru

    Science.gov (United States)

    Emmer, Adam; Walker-Crawford, Noah; Carey, Mark; Huggel, Christian; Verheyen, Roda; Wallimann-Helmer, Ivo

    2017-04-01

    Post-Little Ice Age (LIA) climate change has led to worldwide glacier retreat, formation and evolution of glacial lakes, occasionally followed by glacier lake outburst floods (GLOFs). Hundreds of GLOFs are documented throughout the 20th and 21st century, of which a certain number that caused massive downstream destruction and up to thousands of lives lost. Management of GLOF hazards and risks has typically been a local concern, focusing on the implementation of specific technical and engineering measures. Recently, however, researchers have realized that the complexity of both the risks and the socio-environmental context requires a broader understanding and response beyond the more typical local perception and management. The growing cumulative greenhouse gas (GHG) emissions, for instance, increase the anthropogenic contribution to glacier retreat, lake formation and growth and eventually to GLOF. GLOF hazard and risk management is inherently linked to the global scale from this perspective. It implies that additional important dimensions enter the debate, including ethical and legal questions about the responsibility for damage and loss due to GLOFs. Here we analyze the conditions at an emblematic case in Peru's Cordillera Blanca, which has made international headlines repeatedly since it first generated one of the world's most deadly GLOFs in 1941 to its present-day growth and instability. Situated upstream from the regional center of Huaráz (population ˜120,000), Lake Palcacocha has attracted significant attention in recent years within Peru and at an international level. Perspectives on Palcacocha lack truly cross-disciplinary research, missing more comprehensive insight. This contribution is unique for its analysis of diverse dimensions, which also provide a framework for other GLOF hazard, risk, and climate-related studies. The main aim of this constribution is to understand the links between them, their drivers and inhibitors. Four dimensions were studied

  20. Applications of low altitude remote sensing in agriculture upon farmers' requests--a case study in northeastern Ontario, Canada.

    Science.gov (United States)

    Zhang, Chunhua; Walters, Dan; Kovacs, John M

    2014-01-01

    With the growth of the low altitude remote sensing (LARS) industry in recent years, their practical application in precision agriculture seems all the more possible. However, only a few scientists have reported using LARS to monitor crop conditions. Moreover, there have been concerns regarding the feasibility of such systems for producers given the issues related to the post-processing of images, technical expertise, and timely delivery of information. The purpose of this study is to showcase actual requests by farmers to monitor crop conditions in their fields using an unmanned aerial vehicle (UAV). Working in collaboration with farmers in northeastern Ontario, we use optical and near-infrared imagery to monitor fertilizer trials, conduct crop scouting and map field tile drainage. We demonstrate that LARS imagery has many practical applications. However, several obstacles remain, including the costs associated with both the LARS system and the image processing software, the extent of professional training required to operate the LARS and to process the imagery, and the influence from local weather conditions (e.g. clouds, wind) on image acquisition all need to be considered. Consequently, at present a feasible solution for producers might be the use of LARS service provided by private consultants or in collaboration with LARS scientific research teams.

  1. Disaster management in flash floods in Leh (Ladakh: A case study

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    Preeti Gupta

    2012-01-01

    Full Text Available Background: On August 6, 2010, in the dark of the midnight, there were flash floods due to cloud burst in Leh in Ladakh region of North India. It rained 14 inches in 2 hours, causing loss of human life and destruction. The civil hospital of Leh was badly damaged and rendered dysfunctional. Search and rescue operations were launched by the Indian Army immediately after the disaster. The injured and the dead were shifted to Army Hospital, Leh, and mass casualty management was started by the army doctors while relief work was mounted by the army and civil administration. Objective: The present study was done to document disaster management strategies and approaches and to assesses the impact of flash floods on human lives, health hazards, and future implications of a natural disaster. Materials and Methods: The approach used was both quantitative as well as qualitative. It included data collection from the primary sources of the district collectorate, interviews with the district civil administration, health officials, and army officials who organized rescue operations, restoration of communication and transport, mass casualty management, and informal discussions with local residents. Results: 234 persons died and over 800 were reported missing. Almost half of the people who died were local residents (49.6% and foreigners (10.2%. Age-wise analysis of the deaths shows that the majority of deaths were reported in the age group of 25-50 years, accounting for 44.4% of deaths, followed by the 11-25-year age group with 22.2% deaths. The gender analysis showed that 61.5% were males and 38.5% were females. A further analysis showed that more females died in the age groups <10 years and ≥50 years. Conclusions: Disaster preparedness is critical, particularly in natural disasters. The Army′s immediate search, rescue, and relief operations and mass casualty management effectively and efficiently mitigated the impact of flash floods, and restored normal

  2. Characterization of a Flood Event through a Sediment Analysis: The Tescio River Case Study

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    Silvia Di Francesco

    2016-07-01

    Full Text Available This paper presents the hydrological analysis and grain size characteristics of fluvial sediments in a river basin and their combination to characterize a flood event. The overall objective of the research is the development of a practical methodology based on experimental surveys to reconstruct the hydraulic history of ungauged river reaches on the basis of the modifications detected on the riverbed during the dry season. The grain size analysis of fluvial deposits usually requires great technical and economical efforts and traditional sieving based on physical sampling is not appropriate to adequately represent the spatial distribution of sediments in a wide area of a riverbed with a reasonable number of samples. The use of photographic sampling techniques, on the other hand, allows for the quick and effective determination of the grain size distribution, through the use of a digital camera and specific graphical algorithms in large river stretches. A photographic sampling is employed to characterize the riverbed in a 3 km ungauged reach of the Tescio River, a tributary of the Chiascio River, located in central Italy, representative of many rivers in the same geographical area. To this end, the particle size distribution is reconstructed through the analysis of digital pictures of the sediments taken on the riverbed in dry conditions. The sampling has been performed after a flood event of known duration, which allows for the identification of the removal of the armor in one section along the river reach under investigation. The volume and composition of the eroded sediments made it possible to calculate the average flow rate associated with the flood event which caused the erosion, by means of the sediment transport laws and the hydrological analysis of the river basin. A hydraulic analysis of the river stretch under investigation was employed to verify the validity of the proposed procedure.

  3. Land Use Land Cover Impact on Probable Maximum Flood and Sedimentation for Artificial Reservoirs: A Case Study in Western US

    Science.gov (United States)

    Yigzaw, W. Y.; Hossain, F.

    2014-12-01

    Unanticipated peak inflows that can exceed the inflow design flood (IDF) for spillways and result in possible storage loss in reservoirs from increased sedimentation rates lead to a greater risk for downstream floods. Probable maximum precipitation (PMP) and probable maximum flood (PMF) are mostly used to determine IDF. Any possible change of PMP and PMF due to future land use and land cover (LULC) change therefore requires a methodical investigation. However, the consequential sediment yield, due to altered precipitation and flow patterns into the reservoir has not been addressed in literature. Thus, this study answers the following question: "What is the combined impact of a modified PMP on PMF and sediment yield for an artificial reservoir? The Owyhee dam of Owyhee River watershed (ORW) in Oregon is selected as a case study area for understanding the impact of LULC change on PMF and sedimentation rates. Variable Infiltration Capacity (VIC) is used for simulating stream flow (PMF) and the Revised Universal Soil Loss Equation (RUSLE) to estimate sediment yield over ORW as a result of change in precipitation intensity and LULC. Scenarios that represent pre-Owyhee dam (Pre-Dam) and post Owyhee dam (Non-Irrigation, Control, 1992, 2001, 2006) are used to simulate PMF's and consequential sediment yield. Peak PMF result for Pre-Dam scenarios is found to increase by 26m3s-1 (1%) and 81m3s-1 (3%) from Non-Irrigation and Control scenario, respectively. Considering only LULC change, sediment yield decreased over ORW due to the transformation of LULC from grassland to shrubland (from Pre-Dam period to the post-Dam years). However, increase in precipitation intensity caused a significant (0.1% storage loss over 21days storm period) increase in sediment yield resulting in largely reservoir sedimentation. This study underscores the need to consider future impact of LULC change on IDF calculation as well as sedimentation rates for more robust reservoir operations and planning.

  4. Urbanization and the Risk of Flooding In the Congo; Case of The City Of Brazzaville

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    Nzoussi Hilaire Kevin

    2015-01-01

    Full Text Available Urbanization is the process by which cities grow. For over a decade, African cities in general have had a very significant population growth. And Brazzaville, the political capital of the Republic of Congo has not remained on the sidelines of this exponential growth. This is probably due to the political and economic stability singularly marked by oil upturn. This rapid urbanization contributes to defy all the forecasts made in terms of urbanization and poses many problems. Population growth leads to an occupation with no real urbanization standards of public space in the city which causes uncontrolled building, with major flooding during rainy periods to disproportionate consequences.

  5. Status and ethno-medicinal usage of invasive plants in traditional health care practices: a case study from northeastern Bangladesh

    Institute of Scientific and Technical Information of China (English)

    Mohammed Abu Sayed Arfin Khan; Fahmida Sultana; Md. Habibur Rahman; Bishwajit Roy; Sawon Istiak Anik

    2011-01-01

    Species diversity and ethno-medicinal usage of 39 species of invasive plants were explored in and around two protected areas,Khadinmagar National Park (KNP) and Rema-Kalenga Wildlife Sanctuary (RKWS),of northeastern Bangladesh,.Status of invasive plants were investigated in 60 sample plots with 5 different habitat types,including forest,roadside,homestead,fallow land and others (ponds,canals,water logged areas,agricultural land,etc.).Data about the usage of invasive plants in traditional health care were collected through interviewing 110 households.Among the five habitat types,fallow land (28 species) possessed the highest number of species,followed by roadside (25 species),forest (23 species),homestead (22 species) and others (13 species).Based on the survey,invasive plants of study areas were also categorized into five degrees of invasiveness e.g.,naturalized,introduced,possibly invasive,moderately invasive and highly invasive.Additionally,there is the linear trend between degrees of invasiveness and use percentage of invasive plants.Total 39 species of invasive plants belonging to 29 families were recorded,which are generally used to treat 37 diseases,ranging from simple headache to highly complicated eye and heart diseases.The majority of the species used by the local inhabitants were herbs (16 species),followed by some shrubs (11 species),climbers (5 species),trees (5 species) and grasses (2 species).The use percentage of aboveground plant parts were higher (70.58%) than that of underground plant parts (16.18%).

  6. Global change and viticulture in the Mediterranean region: a case of study in north-eastern Spain

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Bustins, J. A.; Pla, E.; Nadal, M.; Herralde, F. de; Save, R.

    2014-06-01

    Viticulture in the Mediterranean region has been improved by agronomic methods based on eco physiological and genetic knowledge of the species and varieties cultivated. Plant growth, yield and quality are highly dependent on climate. Grape sugar content and wine alcohol content are considered as important quality parameters. The objective of our study is to analyse the effects of the current global change on the percentage of alcohol by volume (ABV) in red wines from vineyards located in the Montsant Designation of Origin (DO) (Priorat County, north-eastern Spain). We present an annual series of percentage of ABV in red wines over the 1984-2008 period (25 years), which is one of the longest series of this viticultural variable in Spain. We do not detect any significant trend of alcohol levels in red wines from the Montsant DO along the 1984-2004 subperiod, but a sharp increase about 1% (by volume) is observed after 2004; we statistically checked that the last four years constitute an outlier period in the series. We consider climate evolution over the 1984-2004 period in the study area in order to find some relation with alcohol levels in red wines. Agronomic practices and land cover changes are also taken into account. Results show that the interannual variability of the alcohol levels in red wines are partially explained by temperature and precipitation conditions few days before the vintage. The high percentages of ABV since 2005 may be associated with new trends in viticulture techniques rather than with climate change. (Author)

  7. Global change and viticulture in the Mediterranean region: a case of study in north-eastern Spain

    Directory of Open Access Journals (Sweden)

    Joan-Albert Lopez-Bustins

    2014-02-01

    Full Text Available Viticulture in the Mediterranean region has been improved by agronomic methods based on ecophysiological and genetic knowledge of the species and varieties cultivated. Plant growth, yield and quality are highly dependent on climate. Grape sugar content and wine alcohol content are considered as important quality parameters. The objective of our study is to analyse the effects of the current global change on the percentage of alcohol by volume (ABV in red wines from vineyards located in the Montsant Designation of Origin (DO (Priorat County, north-eastern Spain. We present an annual series of percentage of ABV in red wines over the 1984-2008 period (25 years, which is one of the longest series of this viticultural variable in Spain. We do not detect any significant trend of alcohol levels in red wines from the Montsant DO along the 1984-2004 subperiod, but a sharp increase about 1% (by volume is observed after 2004; we statistically checked that the last four years constitute an outlier period in the series. We consider climate evolution over the 1984-2004 period in the study area in order to find some relation with alcohol levels in red wines. Agronomic practices and land cover changes are also taken into account. Results show that the interannual variability of the alcohol levels in red wines are partially explained by temperature and precipitation conditions few days before the vintage. The high percentages of ABV since 2005 may be associated with new trends in viticulture techniques rather than with climate change.

  8. A Study of the Precipitation of the Tibetan Plateau Northeastern Side during Flood Seasons%青藏高原东北侧汛期降水若干问题研究

    Institute of Scientific and Technical Information of China (English)

    王宝灵; 谢金南; 吴国雄; 俞亚勋

    2000-01-01

    利用青藏高原东北侧区域平均降水量资料(1958~1997年)和同期NCEP/NCAR再分析500 hPa网格资料(2.5o×2.5o),分析发现:(1)高原东北侧汛期降水份额最大的7、8、9月3个月近40年降水明显减少,过去明显存在的准3年周期振荡80年代以来处于低潮;(2)日本-北太平洋附近位势高度降低,鄂霍茨克海阻高加强是高原东北侧7、8、9月干旱最典型的标志;(3)就干旱流型而言,7月干旱环流与江淮梅雨环流特征十分相似,表现在江淮多梅雨年,一般是高原东北侧重旱年;(4)高原东北侧7~9月的典型旱年流型,实际就是El Nino流型;(5)El Nino事件对高原东北侧降水有明显影响,表现在该区域典型少雨年,一般发生于El Nino事件当年。从阶段看,以7~9月降水总量与El Nino事件相关最为显著,从月际看,尤以9月关系最好。%The NCEP/NCAR reanalysis monthly 500 hPa grid data (2.5o×2.5oLat/Lon) and the monthly precipitation of the Tibetan Plateau Northeastern side from 1958 to 1997 are used and analyzed. The results show that: (1) The precipitation for the recent fourty years is obviously decreased in July, August and September when the precipitation is most concentrated. And the quasi-three year period oscillation, which distinctly existed in the past years, has been in low phase since the 1980s in the Tibetan Plateau Northeastern side. (2) It is the most typical drought indicator in July, August and September of the Tibetan Plateau Northeastern side that the reduction of geopotential height near Japan to the northern Pacific and the intensification of Okhotsk blocking high. (3) For the drought flow patterns, the circulation of the drought years is very similar to that of the Changjiang-Huaihe Meiyu in July. In general, the heavy drought years occur in the Tibetan Plateau northeastern side when the rainy years occur in the Changjiang-Huaihe river basin. (4

  9. Probabilistic flood extent estimates from social media flood observations

    Science.gov (United States)

    Brouwer, Tom; Eilander, Dirk; van Loenen, Arnejan; Booij, Martijn J.; Wijnberg, Kathelijne M.; Verkade, Jan S.; Wagemaker, Jurjen

    2017-05-01

    The increasing number and severity of floods, driven by phenomena such as urbanization, deforestation, subsidence and climate change, create a growing need for accurate and timely flood maps. In this paper we present and evaluate a method to create deterministic and probabilistic flood maps from Twitter messages that mention locations of flooding. A deterministic flood map created for the December 2015 flood in the city of York (UK) showed good performance (F(2) = 0.69; a statistic ranging from 0 to 1, with 1 expressing a perfect fit with validation data). The probabilistic flood maps we created showed that, in the York case study, the uncertainty in flood extent was mainly induced by errors in the precise locations of flood observations as derived from Twitter data. Errors in the terrain elevation data or in the parameters of the applied algorithm contributed less to flood extent uncertainty. Although these maps tended to overestimate the actual probability of flooding, they gave a reasonable representation of flood extent uncertainty in the area. This study illustrates that inherently uncertain data from social media can be used to derive information about flooding.

  10. Multivariate pluvial flood damage models

    Energy Technology Data Exchange (ETDEWEB)

    Van Ootegem, Luc [HIVA — University of Louvain (Belgium); SHERPPA — Ghent University (Belgium); Verhofstadt, Elsy [SHERPPA — Ghent University (Belgium); Van Herck, Kristine; Creten, Tom [HIVA — University of Louvain (Belgium)

    2015-09-15

    Depth–damage-functions, relating the monetary flood damage to the depth of the inundation, are commonly used in the case of fluvial floods (floods caused by a river overflowing). We construct four multivariate damage models for pluvial floods (caused by extreme rainfall) by differentiating on the one hand between ground floor floods and basement floods and on the other hand between damage to residential buildings and damage to housing contents. We do not only take into account the effect of flood-depth on damage, but also incorporate the effects of non-hazard indicators (building characteristics, behavioural indicators and socio-economic variables). By using a Tobit-estimation technique on identified victims of pluvial floods in Flanders (Belgium), we take into account the effect of cases of reported zero damage. Our results show that the flood depth is an important predictor of damage, but with a diverging impact between ground floor floods and basement floods. Also non-hazard indicators are important. For example being aware of the risk just before the water enters the building reduces content damage considerably, underlining the importance of warning systems and policy in this case of pluvial floods. - Highlights: • Prediction of damage of pluvial floods using also non-hazard information • We include ‘no damage cases’ using a Tobit model. • The damage of flood depth is stronger for ground floor than for basement floods. • Non-hazard indicators are especially important for content damage. • Potential gain of policies that increase awareness of flood risks.

  11. Flood modelling with a distributed event-based parsimonious rainfall-runoff model: case of the karstic Lez river catchment

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    M. Coustau

    2012-04-01

    Full Text Available Rainfall-runoff models are crucial tools for the statistical prediction of flash floods and real-time forecasting. This paper focuses on a karstic basin in the South of France and proposes a distributed parsimonious event-based rainfall-runoff model, coherent with the poor knowledge of both evaporative and underground fluxes. The model combines a SCS runoff model and a Lag and Route routing model for each cell of a regular grid mesh. The efficiency of the model is discussed not only to satisfactorily simulate floods but also to get powerful relationships between the initial condition of the model and various predictors of the initial wetness state of the basin, such as the base flow, the Hu2 index from the Meteo-France SIM model and the piezometric levels of the aquifer. The advantage of using meteorological radar rainfall in flood modelling is also assessed. Model calibration proved to be satisfactory by using an hourly time step with Nash criterion values, ranging between 0.66 and 0.94 for eighteen of the twenty-one selected events. The radar rainfall inputs significantly improved the simulations or the assessment of the initial condition of the model for 5 events at the beginning of autumn, mostly in September–October (mean improvement of Nash is 0.09; correction in the initial condition ranges from −205 to 124 mm, but were less efficient for the events at the end of autumn. In this period, the weak vertical extension of the precipitation system and the low altitude of the 0 °C isotherm could affect the efficiency of radar measurements due to the distance between the basin and the radar (~60 km. The model initial condition S is correlated with the three tested predictors (R2 > 0.6. The interpretation of the model suggests that groundwater does not affect the first peaks of the flood, but can strongly impact subsequent peaks in the case of a multi-storm event. Because this kind of model is based on a limited

  12. Identification of spatial and temporal contributions of rainfalls to flash floods using neural network modelling: case study on the Lez Basin (Southern France

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    T. Darras

    2015-04-01

    Full Text Available Flash floods pose significant hazards in urbanised zones and have important human and financial implications in both the present and future due to the likelihood that global climate change will exacerbate their consequences. It is thus of crucial importance to better model these phenomena especially when they occur in heterogeneous and karst basins where they are difficult to describe physically. Toward this goal, this paper applies a recent methodology (KnoX methodology dedicated to extracting knowledge from a neural network model to better determine the contributions and time responses of several well-identified geographic zones of an aquifer. To assess the interest of this methodology, a case study was conducted in Southern France: the Lez hydrosystem whose river crosses the conurbation of Montpellier (400 000 inhabitants. Rainfall contributions and time transfers were estimated and analysed in four geologically-delimited zones to estimate the sensitivity of flash floods to water coming from the surface or karst. The Causse de Viol-le-Fort is shown to be the main contributor to flash floods and the delay between surface and underground flooding is estimated to be three hours. This study will thus help operational flood warning services to better characterise critical rainfall and develop measurements to design efficient flood forecasting models. This generic method can be applied to any basin with sufficient rainfall–runoff measurements.

  13. Representing Geospatial Environment Observation Capability Information: A Case Study of Managing Flood Monitoring Sensors in the Jinsha River Basin

    Science.gov (United States)

    Hu, Chuli; Guan, Qingfeng; Li, Jie; Wang, Ke; Chen, Nengcheng

    2016-01-01

    Sensor inquirers cannot understand comprehensive or accurate observation capability information because current observation capability modeling does not consider the union of multiple sensors nor the effect of geospatial environmental features on the observation capability of sensors. These limitations result in a failure to discover credible sensors or plan for their collaboration for environmental monitoring. The Geospatial Environmental Observation Capability (GEOC) is proposed in this study and can be used as an information basis for the reliable discovery and collaborative planning of multiple environmental sensors. A field-based GEOC (GEOCF) information representation model is built. Quintuple GEOCF feature components and two GEOCF operations are formulated based on the geospatial field conceptual framework. The proposed GEOCF markup language is used to formalize the proposed GEOCF. A prototype system called GEOCapabilityManager is developed, and a case study is conducted for flood observation in the lower reaches of the Jinsha River Basin. The applicability of the GEOCF is verified through the reliable discovery of flood monitoring sensors and planning for the collaboration of these sensors. PMID:27999247

  14. An object-oriented overland flow solver for watershed flood inundation predictions: case study of Ulus basin, Turkey

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    Turan Burak

    2014-09-01

    Full Text Available This paper presents an object-oriented two-dimensional (2-D overland flow model and its application in simulating flood flows over Ulus basin, located in the north of Turkey adjacent to the Black Sea. A new coding implementation according to the class environment created in object oriented C++ programming language is carried out in structuring and building the solver. The model is based on the Godunov type finite volume scheme on unstructured triangular meshes. A mass balance preserving wet/dry boundary solution algorithm is integrated in the numerical scheme to satisfy the positive-depth condition and minimize the numerical instability when treating the propagation of wave front in regions of dry bed. The balance between bed slope and flux terms is also preserved for still water conditions on irregular topography. The 2-D solver is verified by simulating selected dam break cases, where good agreement with measured data is achieved. For the simulation of flood flows in the Ulus basin, in general, the simulated outflow hydrograph is found to compare well with the recorded data. A selected inundation map that is extracted from the model results is also presented to show the water surface level in the Floodplain.

  15. Modelling Atmospheric Rivers and the Potential for Southeast Texas Flooding: A Case Study of the Maya Express and the March 2016 Sabine River Flood

    Science.gov (United States)

    McIntosh, J.; Lander, K.

    2016-12-01

    For three days in March of 2016, southeast Texas was inundated with up to 19 inches of rainfall, swelling the Sabine River to record flood stages. This event was attributed to an atmospheric river (AR), regionally known as the "Maya Express," which carried moisture from the Gulf of Mexico into the Sabine River Basin. Studies by the NOAA/NWS Climate Prediction Center have shown that ARs are occurring more frequently due to the intensification of El Niño that increases the available moisture in the atmosphere. In this study, we analyzed the hydrological and meteorological setup of the event on the Sabine River to characterize the flood threat associated with AR rainfall and simulated how an equivalent AR event would impact an urban basin in Houston, Texas. Our primary data sources included WSR-88D radar-based rainfall estimates and observed data at USGS river gauges. Furthermore, the land surface parameters evaluated included land cover, soil types, basin topology, model-derived soil moisture states, and topography. The spatial distribution of precipitation from the storm was then translated west over the Houston and used to force a hydrologic model to assess the impact of an event comparable to the March 2016 event on Houston's San Jacinto River Basin. The results indicate that AR precipitation poses a flood risk to urbanized areas in southeast Texas because of the low lying topography, impervious pavement, and limited flood control. Due to this hydrologic setup, intense AR rainfall can yield a rapid urban runoff response that overwhelms the river system, potentially endangering the lives and property of millions of people in the Houston area. Ultimately, if the frequency of AR development increases, regional flood potential may increase. Given the consequences established in this study, more research should be conducted in order to better predict the rate of recurrence and effects of Maya Express generated precipitation.

  16. Modeling a glacial lake outburst flood process chain: the case of Lake Palcacocha and Huaraz, Peru

    Science.gov (United States)

    Somos-Valenzuela, Marcelo A.; Chisolm, Rachel E.; Rivas, Denny S.; Portocarrero, Cesar; McKinney, Daene C.

    2016-07-01

    One of the consequences of recent glacier recession in the Cordillera Blanca, Peru, is the risk of glacial lake outburst floods (GLOFs) from lakes that have formed at the base of retreating glaciers. GLOFs are often triggered by avalanches falling into glacial lakes, initiating a chain of processes that may culminate in significant inundation and destruction downstream. This paper presents simulations of all of the processes involved in a potential GLOF originating from Lake Palcacocha, the source of a previously catastrophic GLOF on 13 December 1941, killing about 1800 people in the city of Huaraz, Peru. The chain of processes simulated here includes (1) avalanches above the lake; (2) lake dynamics resulting from the avalanche impact, including wave generation, propagation, and run-up across lakes; (3) terminal moraine overtopping and dynamic moraine erosion simulations to determine the possibility of breaching; (4) flood propagation along downstream valleys; and (5) inundation of populated areas. The results of each process feed into simulations of subsequent processes in the chain, finally resulting in estimates of inundation in the city of Huaraz. The results of the inundation simulations were converted into flood intensity and preliminary hazard maps (based on an intensity-likelihood matrix) that may be useful for city planning and regulation. Three avalanche events with volumes ranging from 0.5 to 3 × 106 m3 were simulated, and two scenarios of 15 and 30 m lake lowering were simulated to assess the potential of mitigating the hazard level in Huaraz. For all three avalanche events, three-dimensional hydrodynamic models show large waves generated in the lake from the impact resulting in overtopping of the damming moraine. Despite very high discharge rates (up to 63.4 × 103 m3 s-1), the erosion from the overtopping wave did not result in failure of the damming moraine when simulated with a hydro-morphodynamic model using excessively conservative soil

  17. GIS and local knowledge in disaster management: a case study of flood risk mapping in Viet Nam.

    Science.gov (United States)

    Tran, Phong; Shaw, Rajib; Chantry, Guillaume; Norton, John

    2009-03-01

    Linking community knowledge with modern techniques to record and analyse risk related data is one way of engaging and mobilising community capacity. This paper discusses the use of the Geographic Information System (GIS) at the local level and the need for integrating modern technology and indigenous knowledge into disaster management. It suggests a way to mobilise available human and technical resources in order to strengthen a good partnership between local communities and local and national institutions. The paper also analyses the current vulnerability of two communes by correlating hazard risk and loss/damage caused by disasters and the contribution that domestic risk maps in the community can make to reduce this risk. The disadvantages, advantages and lessons learned from the GIS flood risk mapping project are presented through the case study of the Quang Tho Commune in Thua Thien Hue province, central Viet Nam.

  18. Flood Analysis Using Hydrological Modeling. Case Study – The Flood In The Upper Catchment Of River Geru, Galaţi County, Romania

    Directory of Open Access Journals (Sweden)

    Balan Isabela

    2015-10-01

    Full Text Available This paper analyzes the flood that occurred between 11th and 13th of September 2013 in the upper catchment of the river Geru. The flood was simulated using the program Mike by DHI with the Unitary Hydrograph Method. As input data, we used the precipitation measured at the Automated Hydrological Sensor Station Cudalbi and radar precipitations. We analyzed the importance of accuracy for input data on the simulation results and the direct influence of setting the proper time steps in achieving the simulated discharge hydrograph. It appears that radar precipitations used as input data lead to a discharge hydrograph with low errors for amplitude and phase of the runoff peak.

  19. ISTSOS, SENSOR OBSERVATION MANAGEMENT SYSTEM: A REAL CASE APPLICATION OF HYDRO-METEOROLOGICAL DATA FOR FLOOD PROTECTION

    Directory of Open Access Journals (Sweden)

    M. Cannata

    2014-01-01

    Full Text Available istSOS (Istituto scienze della Terra Sensor Observation Service is an implementation of the Sensor Observation Service standard from Open Geospatial Consortium (OGC. The development of istSOS started in 2009 in order to provide a simple implementation of the Sensor Observation Service (SOS standard for the management, provision and integration of hydro-meteorological data collected in Canton Ticino (Southern Switzerland. istSOS is entirely written in Python and is based on reliable open source software like PostgreSQL/PostGIS and Apache/mod_wsgi. The authors during this presentation want to illustrate the latest software enhancements together with a real case in a production environment. Latest software enhancement includes the development of a RESTful service and of a Web-based graphical user interface that allows hydrologists a better interaction with measurements. This includes the ability of new services creation, addition of new sensors and relative metadata, visualization and manipulation of stored observations, registration of new measures and setting of system properties like observable properties and data quality codes. The study will show a real case application of the system for the provision of data to interregional partners and to a hydrological model for lake level forecasting and flooding hazard assessment. The hydrological model uses a combination of WPS (Web Processing Service and SOS for the generation of model input data. This system is linked with a dedicated geo-portal used by the civil protection for the management, alert and protection of population and assets of the Locarno area (Verbano Lake flooding. Practical considerations and technical issues will be presented and discussed.

  20. Modeling/GIS, Risk Assessment, Economic Impact: Seasonal Patterns for Entomological Measures of Risk for Exposure to Culex Vectors and West Nile Virus in Relation to Human Disease Cases in Northeastern Colorado

    OpenAIRE

    Bolling, Bethany G.; Barker, Christopher M.; Moore, Chester G.; Pape, W. John; Eisen, Lars

    2009-01-01

    We examined seasonal patterns for entomological measures of risk for exposure to Culex vectors and West Nile virus (family Flaviviridae, genus Flavivirus, WNV) in relation to human WNV disease cases in a five-county area of northeastern Colorado during 2006–2007. Studies along habitat/elevation gradients in 2006 showed that the seasonal activity period is shortened and peak numbers occur later in the summer for Culex tarsalis Coquillett females in foothills-montane areas >1,600 m compared wit...

  1. Risk-informed local action planning against flooding: lessons learnt and way forward for a case study in Spain

    Directory of Open Access Journals (Sweden)

    Castillo-Rodríguez J.T.

    2016-01-01

    Full Text Available After 29 years of the largest flood event in modern times (with the highest recorded rainfall rate at the Iberian Peninsula with 817 mm in 24 hours, the municipality of Oliva faces the challenge of mitigating flood risk through the development and implementation of a local action plan, in line with other existent and ongoing structural measures for flood risk reduction. Located 65 km from Valencia, on the South-Eastern coast of Spain, Oliva is affected by pluvial, river and coastal flooding and it is characterized by a complex and wide-ranging geography and high seasonal variation in population. A quantitative flood risk analysis has been performed to support the definition of flood risk management strategies. This paper shows how hazard, exposure and vulnerability analyses provide valuable information for the development of a local action plan against flooding, for example by identifying areas with highest societal and economic risk levels. It is concluded that flood risk management actions, such as flood warning and monitoring or evacuation, should not be applied homogenously at local scale, but instead actions should be adapted based on spatial clustering. Implications about the impact of education and training on flood risk reduction are also addressed and discusse

  2. Spatial variability and uncertainty in ecological risk assessment: A case study on the potential risk of cadmium for the little owl in a Dutch river flood plain

    NARCIS (Netherlands)

    Kooistra, L.; Huijbregts, M.A.J.; Ragas, A.M.J.; Wehrens, H.R.M.J.; Leuven, R.S.E.W.

    2005-01-01

    This paper outlines a procedure that quantifies the impact of different sources of spatial variability and uncertainty on ecological risk estimates. The procedure is illustrated in a case study that estimates the risks of cadmium for a little owl (Athene noctua vidalli) living in a Dutch river flood

  3. Exploring Flood Resilience Thinking in the Retail Sector under Climate Change: A Case Study of an Estuarine Region of Taipei City

    Directory of Open Access Journals (Sweden)

    Yi-Chang Chiang

    2017-09-01

    Full Text Available With predictions of extreme precipitation and sea-level rise under climate change that may induce morphological changes of estuaries, increased estuarine flood risk needs to be considered. The aim of this case study was to contemplate sustainability from the perspective of flood resilience that focuses on environmental problems and solutions. The study provided insights into retailers’ resilience thinking regarding the flood-prone Shetzu Peninsula in Taipei City. It is of concern that the retailers strategically identified potential flood risks and have developed adaptive knowledge, skills, and networks. The Location Quotient (LQ analysis was conducted to verify that the retail sector of Shetzu Peninsula was considered a basic industry. Further assessments, an interactive visualization model and a consumption intensity map, were provided as supportive data. Based on the results, semi-structured interviews were conducted to explore 15 key retailers’ resilience thinking on how to adapt to floods in terms of risk communication under climate change. This approach is vital to meet the adaptation challenge in the Shetzu Peninsula. As a result, the study indicated that retailers have strategically identified potential weather-related risks and have implemented adaptation plans for each store functions. The study discussed that, in the face of climate change, maladaptation, interactive visualization models for communicating flood risks, and place attachment are key issues to increase flood resilience under climate change. The introduction of adaptation interventions in terms of urban resilience as a part of a comprehensive strategy helps to manage the impacts of climate change towards urban sustainability.

  4. Mechanism evaluation of carbon dioxide miscible flooding : Caoshe oilfield case study

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Y.; Du, Z.; Sun, L. [State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Chengdu (China); Southwest Petroleum Univ., Chengdu (China); Yu, K.; Liu, W.; Chen, Z. [SINOPEC (China). East China Oil Field Branch

    2009-07-01

    This paper investigated the mechanisms of a carbon dioxide (CO{sub 2}) miscible flooding project at an oilfield in China. Laboratory tests included pressure-volume-temperature (PVT), CO{sub 2} injection swelling, and slim tube tests. Results of the experimental tests were then used to construct an equations-of-state (EOS) compositional model with a 1D and 2D profile of an injector-production well group. Changes in fluid composition and the viscosity and density of the oil and vapor phases were characterized as well as the interfacial tension between oil and gas along the grids during the CO{sub 2} injection process. The effect of gas volume and injection pressure on fluid properties was also investigated. the study showed that the minimum miscibility pressure (MMP) of the project is 30 MPa. The model content of the CO{sub 2} in oil phase can be reacted at a formation pressure of 32 MPa with a 70 per cent oil phase. A continuous CO{sub 2} injection method with formation pressures above the MMP was recommended for the field. 10 refs., 3 tabs., 22 figs.

  5. Assessing the robustness of adaptation decisions in river flood defences to uncertainty in climate impact analysis: A case study on the River Suir, Ireland

    Science.gov (United States)

    Murphy, N.; Murphy, C.

    2009-12-01

    Climate change presents a challenging environment for policy makers and planners as future climate projections are fraught with uncertainty. From the formulation of emissions scenarios, through to the output from Global Climate Models to the regional and then the local scale, uncertainty propagates and increases leading to a cascade of uncertainty (Jones, 2001). The level of flood defences for rivers in Ireland has been built to withstand the 1 in 100 year event based on the historic record. However, stream flow due to climate change is likely to increase by 20% in winter by mid century. The Office of Public Works has therefore revised their projections by adding 20% to the 1 in 100 year event as a design feature of their new flood defences. This poster presents a sensitivity analysis of how various aspects of the climate impact assessment affect the revised level of the 1 in 100 year flood. The River Suir is used as a case study. This poster aims to quantify how different aspects of climate impact assessment uncertainty (GCM, Emissions scenario, impact model) affect the revised level of the 1 in 100 year flood and evaluates if the design of flood defences remains robust to the this uncertainty. Authors. Nuala Murphy Conor Murphy

  6. THE VULNERABILITY OF THE TERRITORIAL-ADMINISTRATIVE UNITS TO THE HYDROLOGICAL PHENOMENA OF RISK (FLASH FLOODS. CASE STUDY: THE SUBCARPATHIAN SECTOR OF BUZĂU CATCHMENT

    Directory of Open Access Journals (Sweden)

    Remus PRĂVĂLIE

    2013-06-01

    Full Text Available The present study aims to analyze, on the one hand, the flash-floods forming potential in the Subcarpathian sector of Buzău catchment, an area with high susceptibility to hydrological hazards such as flash-floods, and, on the other hand, the vulnerability of the territorial-administrative units to these risk phenomena. Thus, in the first stage, the Flash floods Susceptibility Index (FFSI index was defined for the Subcarpathian sector of Buzău catchment, based on environmental factors with a relatively static nature, considered causal factors in the flash-flood phenomena genesis. The next stage of this work was the delimitation of the vulnerability index of the territorial-administrative units, based on the highest FFSI index values which correspond to the built surfaces from the analyzed units. The results showed that more than 80% of the territorial-administrative units are exposed to flood phenomena, while almst 20% is currently under serious risk of damage in case of hydrological risk phenomena occurrence.

  7. Motor neuron diseases in the university hospital of Fortaleza (Northeastern Brazil): a clinico-demographic analysis of 87 cases.

    Science.gov (United States)

    Castro-Costa, C M; Oriá, R B; Vale, O C; Arruda, J A; Horta, W G; D'Almeida, J A; Santos, T J; Ramos, R S; Gifoni, M A

    2000-12-01

    In this retrospective (1980-1998) study, we have analyzed clinico-demographically, from the records of the University Hospital of Fortaleza (Brazil), a group of 87 patients showing signs and symptoms of motor neuron diseases (MNDs). Their diagnosis was determined clinically and laboratorially. The WFN criteria were used for amyotrophic lateral sclerosis (ALS) diagnosis. The clinico-demographic analysis of the 87 cases of MNDs showed that 4 were diagnosed as spinal muscular atrophy (SMA), 5 cases as ALS subsets: 2 as progressive bulbar paralysis (PBP), 2 as progressive muscular atrophy (PMA) and 1 as monomelic amyotrophy (MA), and 78 cases of ALS. The latter comprised 51 males and 27 females, with a mean age of 42.02 years. They were sub-divided into 4 groups according to age: from 15 to 29 years (n= 17), 30 to 39 years (n= 18), 40 to 69 years (n= 39) and 70 to 78 years (n= 4). From the 78 ALS patients, 76 were of the classic sporadic form whilst only 2 were of the familial form. The analysis of the 87 patients with MNDs from the University Hospital of Fortaleza showed a predominance of ALS patients, with a high number of cases of juvenile and early onset adult sporadic ALS.

  8. Joint modeling of flood peak discharges, volume and duration: a case study of the Danube River in Bratislava

    Directory of Open Access Journals (Sweden)

    Bačová Mitková Veronika

    2014-09-01

    Full Text Available The study is focused on the analysis and statistical evaluation of the joint probability of the occurrence of hydrological variables such as peak discharge (Q, volume (V and duration (t. In our case study, we focus on the bivariate statistical analysis of these hydrological variables of the Danube River in Bratislava gauging station, during the period of 1876-2013. The study presents the methodology of the bivariate statistical analysis, choice of appropriate marginal distributions and appropriate copula functions in representing the joint distribution. Finally, the joint return periods and conditional return periods for some hydrological pairs (Q-V, V-t, Q-t were calculated. The approach using copulas can reproduce a wide range of correlation (nonlinear frequently observed in hydrology. Results of this study provide comprehensive information about flood where a devastating effect may be increased in the case where its three basic components (or at least two of them Q, V and t have the same significance.

  9. Sensitivity of quantitative precipitation forecasts to boundary layer parameterization: a flash flood case study in the Western Mediterranean

    Directory of Open Access Journals (Sweden)

    M. Zampieri

    2005-01-01

    Full Text Available The 'Montserrat-2000' severe flash flood event which occurred over Catalonia on 9 and 10 June 2000 is analyzed. Strong precipitation was generated by a mesoscale convective system associated with the development of a cyclone. The location of heavy precipitation depends on the position of the cyclone, which, in turn, is found to be very sensitive to various model characteristics and initial conditions. Numerical simulations of this case study using the hydrostatic BOLAM and the non-hydrostatic MOLOCH models are performed in order to test the effects of different formulations of the boundary layer parameterization: a modified version of the Louis (order 1 model and a custom version of the E-ℓ (order 1.5 model. Both of them require a diagnostic formulation of the mixing length, but the use of the turbulent kinetic energy equation in the E-ℓ model allows to represent turbulence history and non-locality effects and to formulate a more physically based mixing length. The impact of the two schemes is different in the two models. The hydrostatic model, run at 1/5 degree resolution, is less sensitive, but the quantitative precipitation forecast is in any case unsatisfactory in terms of localization and amount. Conversely, the non-hydrostatic model, run at 1/50 degree resolution, is capable of realistically simulate timing, position and amount of precipitation, with the apparently superior results obtained with the E-ℓ parameterization model.

  10. An eight-year review of blood culture and susceptibility among sepsis cases in an emergency department in Northeastern Malaysia.

    Science.gov (United States)

    Hashairi, F; Hasan, H; Azlan, K; Deris, Z Z

    2011-12-01

    An understanding of common pathogens and their antibiotic sensitivity patterns is critical for proper management of sepsis in Emergency Department (ED). The goal of the study was to identify common organisms isolated from blood cultures of patients attended to ED and their antimicrobial susceptibility. Beginning from 2002, all cases of positive blood culture collected by the ED, Hospital Universiti Sains Malaysia (HUSM) were recorded and analysed. Over the period of eight years, we documented 995 cases of positive blood cultures. Of these samples, 549 (55.2%) were Gram-negative bacteria; 419 (42.1%) were Gram-positive bacteria; 10 (1.0%) were anaerobic organisms; 10 (1.0%) were fungus; and 7 (0.7%) cases were mixed organisms. Gram-negative bacteria were observed to develop more resistance to antimicrobial agents, especially those commonly used in an outpatient setting with less than 80% sensitivity to ampicillin, cotrimoxazole and ciprofloxacin. By contrast, there has been no marked change in the sensitivity trends of Gram-positive bacteria over the same period. In conclusion, ED physicians are more equipped to initiate empirical antimicrobial therapy especially when dealing with possibility of Gram-negative sepsis.

  11. Urban pluvial flood prediction: a case study evaluating radar rainfall nowcasts and numerical weather prediction models as model inputs.

    Science.gov (United States)

    Thorndahl, Søren; Nielsen, Jesper Ellerbæk; Jensen, David Getreuer

    2016-12-01

    Flooding produced by high-intensive local rainfall and drainage system capacity exceedance can have severe impacts in cities. In order to prepare cities for these types of flood events - especially in the future climate - it is valuable to be able to simulate these events numerically, both historically and in real-time. There is a rather untested potential in real-time prediction of urban floods. In this paper, radar data observations with different spatial and temporal resolution, radar nowcasts of 0-2 h leadtime, and numerical weather models with leadtimes up to 24 h are used as inputs to an integrated flood and drainage systems model in order to investigate the relative difference between different inputs in predicting future floods. The system is tested on the small town of Lystrup in Denmark, which was flooded in 2012 and 2014. Results show it is possible to generate detailed flood maps in real-time with high resolution radar rainfall data, but rather limited forecast performance in predicting floods with leadtimes more than half an hour.

  12. Flow ensemble prediction for flash flood warnings at ungauged basins

    Science.gov (United States)

    Demargne, Julie; Javelle, Pierre; Organde, Didier; Caseri, Angelica; Ramos, Maria-Helena; de Saint Aubin, Céline; Jurdy, Nicolas

    2015-04-01

    Flash floods, which are typically triggered by severe rainfall events, are difficult to monitor and predict at the spatial and temporal scales of interest due to large meteorological and hydrologic uncertainties. In particular, uncertainties in quantitative precipitation forecasts (QPF) and quantitative precipitation estimates (QPE) need to be taken into account to provide skillful flash flood warnings with increased warning lead time. In France, the AIGA discharge-threshold flood warning system is currently being enhanced to ingest high-resolution ensemble QPFs from convection-permitting numerical weather prediction (NWP) models, as well as probabilistic QPEs, to improve flash flood warnings for small-to-medium (from 10 to 1000 km²) ungauged basins. The current deterministic AIGA system is operational in the South of France since 2005. It ingests the operational radar-gauge QPE grids from Météo-France to run a simplified hourly distributed hydrologic model at a 1-km² resolution every 15 minutes (Javelle et al. 2014). This produces real-time peak discharge estimates along the river network, which are subsequently compared to regionalized flood frequency estimates of given return periods. Warnings are then provided to the French national hydro-meteorological and flood forecasting centre (SCHAPI) and regional flood forecasting offices, based on the estimated severity of ongoing events. The calibration and regionalization of the hydrologic model has been recently enhanced to implement an operational flash flood warning system for the entire French territory. To quantify the QPF uncertainty, the COSMO-DE-EPS rainfall ensembles from the Deutscher Wetterdienst (20 members at a 2.8-km resolution for a lead time of 21 hours), which are available on the North-eastern part of France, were ingested in the hydrologic model of the AIGA system. Streamflow ensembles were produced and probabilistic flash flood warnings were derived for the Meuse and Moselle river basins and

  13. Beyond Flood Hazard Maps: Detailed Flood Characterization with Remote Sensing, GIS and 2d Modelling

    Science.gov (United States)

    Santillan, J. R.; Marqueso, J. T.; Makinano-Santillan, M.; Serviano, J. L.

    2016-09-01

    Flooding is considered to be one of the most destructive among many natural disasters such that understanding floods and assessing the risks associated to it are becoming more important nowadays. In the Philippines, Remote Sensing (RS) and Geographic Information System (GIS) are two main technologies used in the nationwide modelling and mapping of flood hazards. Although the currently available high resolution flood hazard maps have become very valuable, their use for flood preparedness and mitigation can be maximized by enhancing the layers of information these maps portrays. In this paper, we present an approach based on RS, GIS and two-dimensional (2D) flood modelling to generate new flood layers (in addition to the usual flood depths and hazard layers) that are also very useful in flood disaster management such as flood arrival times, flood velocities, flood duration, flood recession times, and the percentage within a given flood event period a particular location is inundated. The availability of these new layers of flood information are crucial for better decision making before, during, and after occurrence of a flood disaster. The generation of these new flood characteristic layers is illustrated using the Cabadbaran River Basin in Mindanao, Philippines as case study area. It is envisioned that these detailed maps can be considered as additional inputs in flood disaster risk reduction and management in the Philippines.

  14. BEYOND FLOOD HAZARD MAPS: DETAILED FLOOD CHARACTERIZATION WITH REMOTE SENSING, GIS AND 2D MODELLING

    Directory of Open Access Journals (Sweden)

    J. R. Santillan

    2016-09-01

    Full Text Available Flooding is considered to be one of the most destructive among many natural disasters such that understanding floods and assessing the risks associated to it are becoming more important nowadays. In the Philippines, Remote Sensing (RS and Geographic Information System (GIS are two main technologies used in the nationwide modelling and mapping of flood hazards. Although the currently available high resolution flood hazard maps have become very valuable, their use for flood preparedness and mitigation can be maximized by enhancing the layers of information these maps portrays. In this paper, we present an approach based on RS, GIS and two-dimensional (2D flood modelling to generate new flood layers (in addition to the usual flood depths and hazard layers that are also very useful in flood disaster management such as flood arrival times, flood velocities, flood duration, flood recession times, and the percentage within a given flood event period a particular location is inundated. The availability of these new layers of flood information are crucial for better decision making before, during, and after occurrence of a flood disaster. The generation of these new flood characteristic layers is illustrated using the Cabadbaran River Basin in Mindanao, Philippines as case study area. It is envisioned that these detailed maps can be considered as additional inputs in flood disaster risk reduction and management in the Philippines.

  15. Analysing diagenetic effects of flood basalts on sedimentary basins during Gondwanan break-up: case studies from NW Namibia.

    Science.gov (United States)

    Thompson, G. A.; Jerram, D. A.; Harris, C.; Pearson, D. G.

    2003-04-01

    ABSTRACT The eruption of large volumes of lava associated with the break-up and dispersal of the Gondwana Supercontinent is a phenomenon that has been well documented in literature. The Etendeka Flood Basalt Province of NW Namibia is correlated with the Paraná Flood Basalt Province of South America and was extruded between 139Ma for the earliest flows and 130Ma for the most recent. The passive, inflated pahoehoe lava flows have preserved bedforms within sand dunes found in the Huab Basin without significant deformation. This allows the internal structures of the palaeo-dunes to be analysed with great accuracy; a phenomenon rarely seen within the geological record. The sediments directly beneath, and interbedded with, the Etendeka Flood Basalt are lithostratigraphically similar to those in the Kudu Gas Province, offshore Namibia, where gas-bearing aeolian sands are interspersed with lava flows. Research by the authors is focussed on the diagenetic effects, both direct and indirect, of the emplacement of the lava, and the associated sills and dykes, on the aeolian sands. Specific interests include: the compartmentalisation of the basin by sills/dykes/lava: how does this affect fluid flow paths? Diagenesis along hot contacts: is the dramatic reduction in porosity/permeability along such contacts the result of the igneous bodies alone or do they need ground water present? Can large igneous events trigger the movement of hot fluids through the basin and to what extent does this cause alteration to sediments? To address these issues we have identified a number of outcrop case studies within the Huab Basin in NW Namibia. Here, excellent 3 dimensional outcrop coupled with almost 100 percent exposure allows detailed sampling strategies to be employed on locations of interest. In some cases igneous dykes have acted as flow barriers to pore fluids and have therefore altered the type and degree of cementation either side of the dyke. Geochemical analysis of the cement can

  16. Extended Brugge benchmark case for history matching and water flooding optimization

    NARCIS (Netherlands)

    Peters, E.; Chen, Y.; Leeuwenburgh, O.; Oliver, D.S.

    2013-01-01

    The Brugge benchmark case designed for the SPE Applied Technology Workshop (ATW) held in Brugge in June 2008 has proven to be valuable for testing and comparing methods of history matching, production optimization and closed-loop optimization by its extensive use in literature. Key features that con

  17. Building network-level resilience to resource disruption from flooding: Case studies from the Shetland Islands and Hurricane Sandy

    Directory of Open Access Journals (Sweden)

    Brown Shaun

    2016-01-01

    Full Text Available Flood events, at a range of scales, have led to disruption of resources such as water, food, materials and goods are vital to the safety, health and livelihoods of individuals and communities. Increasing interdependencies across infrastructures and supply chains pose substantial challenges for those seeking to move resources, and flood risk managers aiming to reduce the disruption to resource movements before, during and after a flood event. This paper introduces a quantitative resource model that embeds input-output relationships of supply and demand within a spatial network model which enables the impacts of a spatial hazard, such as a flood, to be evaluated. The model has been tested in the Shetland Islands and New York City. The analysis supports observations that a single flood event can disrupt the movement of resources far beyond the flooded area. Disruption of critical sectors can rapidly lead to collapse of the entire system given certain conditions. Resource management strategies, such as diversifying supply chains, reduced clustering of industry and storing supplies locally are shown to reduce the magnitude of the initial impact, and slow the propagation of the disruption through the system – providing useful insights to flood risk managers and planners.

  18. Flood modelling with global precipitation measurement (GPM) satellite rainfall data: a case study of Dehradun, Uttarakhand, India

    Science.gov (United States)

    Sai Krishna, V. V.; Dikshit, Anil Kumar; Pandey, Kamal

    2016-05-01

    Urban expansion, water bodies and climate change are inextricably linked with each other. The macro and micro level climate changes are leading to extreme precipitation events which have severe consequences on flooding in urban areas. Flood simulations shall be helpful in demarcation of flooded areas and effective flood planning and preparedness. The temporal availability of satellite rainfall data at varying spatial scale of 0.10 to 0.50 is helpful in near real time flood simulations. The present research aims at analysing stream flow and runoff to monitor flood condition using satellite rainfall data in a hydrologic model. The satellite rainfall data used in the research was NASA's Integrated Multi-satellite Retrievals for Global Precipitation Measurement (IMERG), which is available at 30 minutes temporal resolution. Landsat data was used for mapping the water bodies in the study area. Land use land cover (LULC) data was prepared using Landsat 8 data with maximum likelihood technique that was provided as an input to the HEC-HMS hydrological model. The research was applied to one of the urbanized cities of India, viz. Dehradun, which is the capital of Uttarakhand State. The research helped in identifying the flood vulnerability at the basin level on the basis of the runoff and various socio economic parameters using multi criteria analysis.

  19. Analyzing historical land use changes using a Historical Land Use Reconstruction Model: a case study in Zhenlai County, northeastern China.

    Science.gov (United States)

    Yang, Yuanyuan; Zhang, Shuwen; Liu, Yansui; Xing, Xiaoshi; de Sherbinin, Alex

    2017-01-30

    Historical land use information is essential to understanding the impact of anthropogenic modification of land use/cover on the temporal dynamics of environmental and ecological issues. However, due to a lack of spatial explicitness, complete thematic details and the conversion types for historical land use changes, the majority of historical land use reconstructions do not sufficiently meet the requirements for an adequate model. Considering these shortcomings, we explored the possibility of constructing a spatially-explicit modeling framework (HLURM: Historical Land Use Reconstruction Model). Then a three-map comparison method was adopted to validate the projected reconstruction map. The reconstruction suggested that the HLURM model performed well in the spatial reconstruction of various land-use categories, and had a higher figure of merit (48.19%) than models used in other case studies. The largest land use/cover type in the study area was determined to be grassland, followed by arable land and wetland. Using the three-map comparison, we noticed that the major discrepancies in land use changes among the three maps were as a result of inconsistencies in the classification of land-use categories during the study period, rather than as a result of the simulation model.

  20. Ecological risk assessment for small omnivorous mammals exposed to polycyclic aromatic hydrocarbons: a case study in northeastern Mexico.

    Science.gov (United States)

    Flores-Serrano, Rosa María; Iturbe-Argüelles, Rosario; Pérez-Casimiro, Guillermina; Ramírez-González, Adriana; Flores-Guido, José Salvador; Kantún-Balam, Jesús Martín

    2014-04-01

    An ecological risk assessment (ERA) was performed using the hazard quotient (HQ) method to evaluate the risks of oral exposure to polycyclic aromatic hydrocarbons (PAHs) for medium sized omnivorous mammals. This is the first in a series of three papers. In Mexico there is little experience in performing this kind of assessment for the terrestrial compartment, in particular for birds and mammals exposed to hydrocarbons. The purpose of this paper is to perform an ERA and to establish if the omnivorous mammalian species living in the area are at risk of adverse effects. The studied site is a land that in past years had been used for the disposition of petroleum tank bottom sludges, and scrap metals. Soil and water samples were collected and analyzed, and we obtained a list of the site's wildlife species as well as samples of the specimens, which were analyzed also. HQs were calculated for the hydrocarbons identified as chemicals of potential ecological concern (COPECs) and the omnivorous mammals of the site were evaluated. Toxicity reference values (TRVs) were taken from the appropriate literature, and the doses of exposure were estimated considering the ingestion of water, soil, and diet. Results indicated that potential risks associated to the oral exposure route were less than benchmarks for effects (in all cases HQMexico. This should be primarily aimed at obtaining TRVs for mammals, and consider test species with body weights more similar to those found in the local fauna. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. A study case of Baranca drainage basin flash-floods using the hydrological model of Hec-Ras

    Directory of Open Access Journals (Sweden)

    Aritina HALIUC

    2012-09-01

    Full Text Available In the last decades, the floods which occurred within Romanian territory stand as proof for the increased frequency of the extreme hydrological hazards which have negative effects on the normal pathway of the human-beings activities. The technological progress among with the increased frequency of floods events are the base for the development of informational programs for the analysis, simulation and flood management. The Baranca brook which drains a considerable part of Zamostea village (Romania was used as a pilot drainage basin for the flash-flood simulation using the Hec-Ras program and the Arcgis extension, HecGeo-Ras. The flash-floods that occurred in the summer of 2010 were used to validate the results of the simulation. Between 28.06.2010 – 29.06.2010, two flash-floods occurred in the Baranca drainage basin with a discharge oscillated between 10m3 and 70m3, a water extent which covered an area of 5.14 km2 and a depth ranging between 0.3-3m. The programs are capable to simulate the water flow and to investigate the floodway encroachments in the study area. The damages evaluated in the field along with the program’s results reveal the fact that more than half of the built-up areas of Zamostea village are established along brooks, within the floodplain area. What is more, after the 2010 floods, the expension of the habitable area was not detained by the water danger, many houses are still built on the floodplain. The programs used, taking an acceptable margin of error, may be integrated into any flood management strategy or in any watershed plan and may provide the necessary support for mitigating the risks associated with floods

  2. Socio-Economic Appraisal of Flood Hazard among the Riparian Communities: Case Study of Brahmaputra Valley in Assam; India

    Science.gov (United States)

    Roy, Nikhil; Wasini Pandey, Bindhy

    2017-04-01

    Brahmaputra valley of Assam is one of the most hazard prone areas of the Indian subcontinent. Recurring floods have severely affected the riparian communities of the region since time immemorial. But, the frequency of the problem has been intensified after the great earthquakes of 1897 and 1950. These two extreme earthquakes have disturbed the geological setting of the basin and the channel morphology has been altered henceforth. The impact of floods on riparian communities in Brahmaputra valley has been abysmal. During the monsoon season almost 30 per cent of the valley has been inundated with floods and the riparian communities are mostly affected. Large chunk of people have been uprooted from their native lands due to recurring floods in the low lying areas of the region. Although it is impossible to quantify the human tragedy during the natural disasters, but one can easily understand the situation by the facts that about 1.8 million people and 200,000 hectares of farmland were affected in the 2016 floods of Assam. In the present study, an attempt has been made to assess the spatio-temporal changes of the morphology of Brahmaputra River and its impact on the livelihood of the riparian communities. For that, LANDSAT and SENTINEL imageries have been used to examine the shifting of bank lines of three decades. CARTOSAT DEM has been used to prepare the FLOOD HAZARD ZONATION map of the Brahmaputra valley to examine the flood vulnerable areas of the region. The present study also tries to explain the livelihood condition of the Internally Displaced Persons and their social cohesion. Keywords: Brahmaputra River, Flood, LANDSAT, CARTOSAT DEM, FLOOD HAZARD ZONATION, Riparian Communities

  3. Atmospheric Rivers, Floods, and Flash Floods in California

    Science.gov (United States)

    Skelly, Klint T.

    Atmospheric Rivers (ARs) are long (>2000 km), narrow (<1000 km) corridors of enhanced vertically integrated water vapor (IWV) and enhanced IWV transport (IVT). The landfall of ARs along the U.S. West Coast have been linked to extreme precipitation and flooding/flash flooding in regions of complex topography. The objective of this study is to investigate the relationship between a 10 water-year (2005-2014) climatology of floods, flash floods, and landfalling ARs. The ARs in this study are defined using IVT following the Rutz et al. (2013) methodology, whereas floods and flash floods are identified by the National Centers for Environmental Information (NCEI) Storm Events Database. The results of this study indicate that landfalling ARs are present on a majority of days that there are floods in northern California. Landfalling ARs are predominantly present on a majority of days that there are flash flood reports during the cold-season (November-March); however, the North American monsoon is present on days that there are flash flood reports during the warm-season (April-October). Two exemplary case studies are provided to illustrate the hydrologic impact of landfalling ARs. The first case study illustrated a flood event that occurred in associated with three landfalling ARs that produced 800 mm in regions over the Russian River watershed in northern California and the second case study illustrated a flash flood event that occurred in association with a landfalling AR that produced ˜225 mm of precipitation in regions over the Santa Ynez xii watershed in which produced a flash flood over the southern portions of Santa Barbara County in southern California.

  4. istSOS, a new sensor observation management system: software architecture and a real-case application for flood protection

    Directory of Open Access Journals (Sweden)

    M. Cannata

    2015-11-01

    Full Text Available istSOS (Istituto scienze della Terra Sensor Observation Service is an implementation of the Sensor Observation Service (SOS standard from the Open Geospatial Consortium. The development of istSOS started in 2009 in order to provide a simple implementation of the SOS for the management, provision and integration of hydro-meteorological data collected in Canton Ticino (Southern Switzerland. istSOS is an Open Source, entirely written in Python and based on reliable software like PostgreSQL/PostGIS and Apache/mod_wsgi. This paper illustrates the latest software enhancements, including a RESTful Web service and a Web-based graphical user interface, which enable a better and simplified interaction with measurements and SOS service settings. The robustness of the implemented solution has been validated in a real-case application: the Verbano Lake Early Warning System. In this application, near real-time data have to be exchanged by inter-regional partners and used in a hydrological model for lake level forecasting and flooding hazard assessment. This system is linked with a dedicated geoportal used by the civil protection for the management, alert and protection of the population and the assets of the Locarno area. Practical considerations, technical issues and foreseen improvements are presented and discussed.

  5. A reflection about the social and technological aspects in flood risk management - the case of the Italian Civil Protection

    Science.gov (United States)

    Llasat, M. Del Carmen; Siccardi, F.

    2010-01-01

    The right of a person to be protected from natural hazards is a characteristic of the social and economical development of the society. This paper is a contribution to the reflection about the role of Civil Protection organizations in a modern society. The paper is based in the inaugural conference made by the authors on the 9th Plinius Conference on Mediterranean Storms. Two major issues are considered. The first one is sociological; the Civil Protection organizations and the responsible administration of the land use planning should be perceived as reliable as possible, in order to get consensus on the restrictions they pose, temporary or definitely, on the individual free use of the territory as well as in the entire warning system. The second one is technological: in order to be reliable they have to issue timely alert and warning to the population at large, but such alarms should be as "true" as possible. With this aim, the paper summarizes the historical evolution of the risk assessment, starting from the original concept of "hazard", introducing the concepts of "scenario of event" and "scenario of risk" and ending with a discussion about the uncertainties and limits of the most advanced and efficient tools to predict, to forecast and to observe the ground effects affecting people and their properties. The discussion is centred in the case of heavy rains and flood events in the North-West of Mediterranean Region.

  6. Spatially quantitative models for vulnerability analyses and resilience measures in flood risk management: Case study Rafina, Greece

    Science.gov (United States)

    Karagiorgos, Konstantinos; Chiari, Michael; Hübl, Johannes; Maris, Fotis; Thaler, Thomas; Fuchs, Sven

    2013-04-01

    We will address spatially quantitative models for vulnerability analyses in flood risk management in the catchment of Rafina, 25 km east of Athens, Greece; and potential measures to reduce damage costs. The evaluation of flood damage losses is relatively advanced. Nevertheless, major problems arise since there are no market prices for the evaluation process available. Moreover, there is particular gap in quantifying the damages and necessary expenditures for the implementation of mitigation measures with respect to flash floods. The key issue is to develop prototypes for assessing flood losses and the impact of mitigation measures on flood resilience by adjusting a vulnerability model and to further develop the method in a Mediterranean region influenced by both, mountain and coastal characteristics of land development. The objective of this study is to create a spatial and temporal analysis of the vulnerability factors based on a method combining spatially explicit loss data, data on the value of exposed elements at risk, and data on flood intensities. In this contribution, a methodology for the development of a flood damage assessment as a function of the process intensity and the degree of loss is presented. It is shown that (1) such relationships for defined object categories are dependent on site-specific and process-specific characteristics, but there is a correlation between process types that have similar characteristics; (2) existing semi-quantitative approaches of vulnerability assessment for elements at risk can be improved based on the proposed quantitative method; and (3) the concept of risk can be enhanced with respect to a standardised and comprehensive implementation by applying the vulnerability functions to be developed within the proposed research. Therefore, loss data were collected from responsible administrative bodies and analysed on an object level. The used model is based on a basin scale approach as well as data on elements at risk exposed

  7. Household adoption behaviour and agricultural sustainability in the northeastern mountains of Tanzania : the case of soil conservation in the North Pare and West Usambara Mountains

    NARCIS (Netherlands)

    Semgalawe, Z.M.

    1998-01-01

    The northeastern mountains make up the major part of agricultural land in Tanzania. These areas have been experiencing rapid population growth, leading to increased demand for food, fuelwood and agricultural land. Most parts of the slopes have been experiencing declining soil fertility and severe so

  8. The north-eastern aeolian 'European Sand Belt' as potential record of environmental changes: A case study from Eastern Latvia and Southern Estonia

    DEFF Research Database (Denmark)

    Kalińska-Nartiša, Edyta; Thiel, Christine; Nartišs, Maris

    2016-01-01

    The Latvian and Estonian inland dunes belong to the north-eastern part of the 'European Sand Belt' (ESB). These dunes are widely distributed over broad glaciolacustrine plains and Late Glacial alluvial deltas, considered to be potential sources for the aeolian material. Little is known about...

  9. Household adoption behaviour and agricultural sustainability in the Northeastern Mountains of Tanzania : the case of soil conservation in the North Pare and West Usambara Mountains

    NARCIS (Netherlands)

    Zainab Mbaga Semgalawe,

    1998-01-01

    The northeastern mountains make up the major part of agricultural land in Tanzania. These areas have been experiencing rapid population growth, leading to increased demand for food, fuelwood and agricultural land. Most parts of the slopes have been experiencing declining soil fertility and

  10. The impact of a prominent rain shadow on flooding in California's Santa Cruz Mountains: A CALJET case study and sensitivity to the ENSO cycle

    Science.gov (United States)

    Ralph, F.M.; Neiman, P.J.; Kingsmill, D.E.; Persson, P.O.G.; White, A.B.; Strem, E.T.; Andrews, E.D.; Antweiler, R.C.

    2003-01-01

    Data from the California Land-Falling Jets Experiment (CALJET) are used to explore the causes of variations in flood severity in adjacent coastal watersheds within the Santa Cruz Mountains on 2-3 February 1998. While Pescadero Creek (rural) experienced its flood of record, the adjacent San Lorenzo Creek (heavily populated), attained only its fourth-highest flow. This difference resulted from conditions present while the warm sector of the storm, with its associated low-level jet, high moisture content, and weak static stability, was overhead. Rainfall in the warm sector was dominated by orographic forcing. While the wind speed strongly modulated rain rates on windward slopes, the wind direction positioned the edge of a rain shadow cast by the Santa Lucia Mountains partially over the San Lorenzo basin, thus protecting the city of Santa Cruz from a more severe flood. Roughly 26% ?? 9% of the streamflow at flood peak on Pescadero Creek resulted from the warm-sector rainfall. Without this rainfall, the peak flow on Pescadero Creek would likely not have attained record status. These results are complemented by a climatological analysis based on ???50-yr-duration streamflow records for these and two other nearby windward watersheds situated ???20 to 40 km farther to the east, and a comparison of this climatological analysis with composites of NCEP-NCAR reanalysis fields. The westernmost watersheds were found to have their greatest floods during El Nin??o winters, while the easternmost watersheds peaked during non-El Nin??o episodes. These results are consistent with the case study, that showed that the composite 925-mb, meridionally oriented wind direction during El Nin??os favors a rain shadow over the eastern watersheds. During non-El Nin??o periods, the composite, zonally oriented wind direction indicates that the sheltering effect of the rain shadow on the eastern watersheds is reduced, while weaker winds, less water vapor, and stronger stratification reduce the peak

  11. Is Climate Chang Responsible to Recent Urban Flooding in Devloping Cities in Africa? A Case study of Addis Ababa City, Ethiopia

    Science.gov (United States)

    Moges, Semu; Raschid-Sally, Liqa; Gebremichael, Mekonnen

    2013-04-01

    Cities in Africa show extraordinary expansion of the built environment and imperviousness of the surface condition. Addis Ababa is a case in point, where over the priod of 1984 to 2002, the city asphalted area has increased from 4.72 sq.km (1984) to 27.7 sq.km (2002). Similarly the paved area has expanded five fold from the original 11.1 sq.km, whilst the built environment expanded from 60.1 to 212.7 sq.km. Using hydrological modeling, we demonstrated due to the surface condition change, runoff generation potential has shown significant increase from 28% (in 1984) to 45% (in 2002), showing over 60% change in the runoff volume. The changing condition of the surface is increasing anabtedly, worsening the flooding condition. Similarly, climate change study shows likely increase of precipitation in and around Addis Ababa by about 13 to 17% and comparative increase in flooding. Unlike many cities in Europe, cities in developing countries are confronted with impact emanating from climate change as well as surface condition change. The impact of flooding caused due to the expansion of built environment is found to be more significant in the short term that the climate change, however, the climate change may dominate the long term future of flooding pattern as cities mature towards 2050. Therefore, It is important to view the impacts expansion of built environment and climate change in tandem in future time horizon since the dominance of the impact is different in different temporal scale. In the case of Addis Ababa, we strongly present the following four suggesions: i) the city adminstration re-estabilish the abandoned flood and drainage department of the city as the main flood regulatory and management body working in tandem with Addis Ababa Roads Authority, Water Supply and Sanitation Authority and Urban Planning Authority; ii) The old design guidlines for palnning and design of urban drainage system is not working any more (assumed stationarity condition), we suggest

  12. The place behind the case: leptospirosis risks and associated environmental conditions in a flood-related outbreak in Rio de Janeiro

    Directory of Open Access Journals (Sweden)

    Barcellos Christovam

    2001-01-01

    Full Text Available The environmental context in which a leptospirosis outbreak took place during the summer of 1996 in the Rio de Janeiro Western Region was examined by using spatial analysis of leptospirosis cases merged with socio-demographic data using Geographic Information System (GIS. Risk areas were mapped based on flood and solid waste accumulation information for the region. Incidence rates were calculated for each area by the division of number of cases per total population in the specific areas. Higher rates were observed for census tracts inside the flood risk area and in the vicinities of waste accumulation sites. These findings are in agreement with the expected risk of leptospirosis, evidencing the role of environmental and collective factors in the determination of the disease.

  13. The place behind the case: leptospirosis risks and associated environmental conditions in a flood-related outbreak in Rio de Janeiro

    Directory of Open Access Journals (Sweden)

    Christovam Barcellos

    Full Text Available The environmental context in which a leptospirosis outbreak took place during the summer of 1996 in the Rio de Janeiro Western Region was examined by using spatial analysis of leptospirosis cases merged with socio-demographic data using Geographic Information System (GIS. Risk areas were mapped based on flood and solid waste accumulation information for the region. Incidence rates were calculated for each area by the division of number of cases per total population in the specific areas. Higher rates were observed for census tracts inside the flood risk area and in the vicinities of waste accumulation sites. These findings are in agreement with the expected risk of leptospirosis, evidencing the role of environmental and collective factors in the determination of the disease.

  14. The beginning of explosive eruptions on a location lacking volcanoes: A case study on the Hijiori volcano, Northeastern Japan

    Science.gov (United States)

    Miyagi, I.

    2006-12-01

    The volcanic activity of Hijiori volcano (N38 36°f 35°f°f, E140 9°f 20°f°f, WGS84) is reported in detail as a case study to understand how a new felsic volcano commences the activity. Hijiori volcano, a small caldera with approximately 2 km in diameter, is one of the 108 active volcanoes in Japan, which erupted at about 12,000 years ago (in Calendar age) on the location where no volcanic body existed before the activity. From the field survey, it turns out that the suite of activities initiated by the major eruption that deposited a valley filling non-welded pumice flows. Finally the pumice flows covered the range 5 km to the southward and 9 km to the northward with total maximum thickness of about 150 m. The accompanying pumice fall and ash fall extends 60 km to the eastward. Although span of the activity is as short as the resolving power of radiocarbon dating, there recognized a quiescence for three times. After the every quiescence, phreatic (or phreatomagmatic) activities deposited lapilli falls and flows in the proximity. Total volume of the valley filling pyroclastic flows and the air falls are estimated to be 1.4 and 0.6 cubic km, respectively. All the pumices from the three major eruptions are similar in their phenocryst content (50- vol. percent), phenocryst assemblages (Pl, Qz, OPx, Hb, and Mt), bulk chemistry (c.a. 64 wt. percent SiO2), and in isotopic (Sr, Nd) compositions. Mt phenocrysts have no zoning profiles and their chemical compositions (Al2O3, Mg/Mn) are mostly unique through the eruptive sequences, suggesting that the physicochemical conditions of the magma were the same just before the each eruption. On the contrary Pl, Qz, OPx and Hb phenocrysts showed distinct zoning, suggesting that the magma chamber of Hijiori volcano had been disturbed repeatedly by such as magma mixing that continued intermittently before and during the eruptive activities. The observed difference between Mt and the other phenocrysts implies that there were

  15. Flooding and intestinal illness due to Clostridium difficile infection: a case-crossover analysis of Massachusetts data, 2003-2007

    Science.gov (United States)

    Background. Climate change has contributed to a rise in extreme weather events, including heavier rainfalls. Floods can cause water bodies to overflow, damage water treatment and drinking water infrastructure, overwhelm sewage treatment facilities, and result in discharges of un...

  16. Flooding and intestinal illness due to Clostridium difficile infection: a case-crossover analysis of Massachusetts data, 2003-2007

    Science.gov (United States)

    Background. Climate change has contributed to a rise in extreme weather events, including heavier rainfalls. Floods can cause water bodies to overflow, damage water treatment and drinking water infrastructure, overwhelm sewage treatment facilities, and result in discharges of un...

  17. Response of Vegetation on Gravel Bars to Management Measures and Floods: Case Study From the Czech Republic

    Directory of Open Access Journals (Sweden)

    Eremiášová Renata

    2014-08-01

    Full Text Available This article investigates response of vegetation on gravel bars to management measures and floods. The management measures consisted of the partial removal of gravel and vegetation cover, and were applied to six gravel bars on the Ostravice River, Czech Republic. Unexpected floods occu-rred in 2010, with the amplitude of 5- to 50-year repetition. Research of vegetation on the gravel bars consisted of vegetation survey before the management works; the monitoring of vegetation development over the following year and the verification of the relationships of species diversity, successional stages and the biotope conditions with the help of multivariate analysis (detrended correspondence analysis. Vegetation on the gravel bars was at different successional stages, and had higher diversity and vegetation cover before the management measures and floods. The mul-tivariate analysis revealed a shift toward initial successional stages with high demand on moisture, temperature and light after both management measures and floods.

  18. Has land subsidence changed the flood hazard potential? A case example from the Kujukuri Plain, Chiba Prefecture, Japan

    Science.gov (United States)

    Chen, H. L.; Ito, Y.; Sawamukai, M.; Su, T.; Tokunaga, T.

    2015-11-01

    Coastal areas are subject to flood hazards because of their topographic features, social development and related human activities. The Kujukuri Plain, Chiba Prefecture, Japan, is located nearby the Tokyo metropolitan area and it faces to the Pacific Ocean. In the Kujukuri Plain, widespread occurrence of land subsidence has been caused by exploitation of groundwater, extraction of natural gas dissolved in brine, and natural consolidation of the Holocene and landfill deposits. The locations of land subsidence include areas near the coast, and it may increase the flood hazard potential. Hence, it is very important to evaluate flood hazard potential by taking into account the temporal change of land elevation caused by land subsidence, and to prepare hazard maps for protecting the surface environment and for developing an appropriate land-use plan. In this study, flood hazard assessments at three different times, i.e., 1970, 2004, and 2013 are implemented by using a flood hazard model based on Multicriteria Decision Analysis with Geographical Information System techniques. The model incorporates six factors: elevation, depression area, river system, ratio of impermeable area, detention ponds, and precipitation. Main data sources used are 10 m resolution topography data, airborne laser scanning data, leveling data, Landsat-TM data, two 1:30 000 scale river watershed maps, and precipitation data from observation stations around the study area and Radar data. The hazard assessment maps for each time are obtained by using an algorithm that combines factors with weighted linear combinations. The assignment of the weight/rank values and their analysis are realized by the application of the Analytic Hierarchy Process method. This study is a preliminary work to investigate flood hazards on the Kujukuri Plain. A flood model will be developed to simulate more detailed change of the flood hazard influenced by land subsidence.

  19. Appraising sustainable flood risk management in the Pearl River Delta's coastal megacities: A case study of Hong Kong, China

    OpenAIRE

    Chan, F. K. S.; Adekola, O. A.; Mitchell, G.; McDonald, A. T.

    2013-01-01

    The Pearl River Delta (PRD) region has experienced rapid economic and population growth in the last three decades. The delta includes coastal megacities, such as Hong Kong. These low-lying urbanised coastal regions in the PRD are vulnerable to flood risks from unpredictable climatic conditions. These can result in increasing storm surges, rising sea level and intensified rainstorms causing coastal and inland flooding, all of which impact the delta. This paper has taken the coastal megacity of...

  20. Social vulnerability assessment of flood risk using GISbased multicriteria decision analysis. A case study of Vila Nova de Gaia (Portugal)

    OpenAIRE

    Paulo Fernandez; Sandra Mourato; Madalena Moreira

    2015-01-01

    Over the last decade, flood disasters have affected millions of people and caused massive economic losses. Social vulnerability assessment uses a combination of several factors to represent a population's differential access to resources and its ability to cope with and respond to hazards. In this paper, social vulnerability assessment to flood risk was applied to the third most populous Portuguese municipality. The study was developed at the neighbourhood level, allowing for social vulnerabi...

  1. Real-time flood forecasting coupling different postprocessing techniques of precipitation forecast ensembles with a distributed hydrological model. The case study of may 2008 flood in western Piemonte, Italy

    Directory of Open Access Journals (Sweden)

    D. Cane

    2013-02-01

    Full Text Available In this work, we compare the performance of an hydrological model when driven by probabilistic rain forecast derived from two different post-processing techniques. The region of interest is Piemonte, northwestern Italy, a complex orography area close to the Mediterranean Sea where the forecast are often a challenge for weather models. The May 2008 flood is here used as a case study, and the very dense weather station network allows us for a very good description of the event and initialization of the hydrological model. The ensemble probabilistic forecasts of the rainfall fields are obtained with the Bayesian model averaging, with the classical poor man ensemble approach and with a new technique, the Multimodel SuperEnsemble Dressing. In this case study, the meteo-hydrological chain initialized with the Multimodel SuperEnsemble Dressing is able to provide more valuable discharge ranges with respect to the one initialized with Bayesian model averaging multi-model.

  2. The contribute of DInSAR techniques to landslide hazard evaluation in mountain and hilly regions: a case study from Agno Valley (North-Eastern Italian Alps)

    Science.gov (United States)

    De Agostini, A.; Floris, M.; Pasquali, P.; Barbieri, M.; Cantone, A.; Riccardi, P.; Stevan, G.; Genevois, R.

    2012-04-01

    In the last twenty years, Differential Synthetic Aperture Radar Interferometry (DInSAR) techniques have been widely used to investigate geological processes, such as subsidence, earthquakes and landslides, through the evaluation of earth surface displacements caused by these processes. In the study of mass movements, contribution of interferometry can be limited due to the acquisition geometry of RADAR images and the rough morphology of mountain and hilly regions which represent typical landslide-prone areas. In this study, the advanced DInSAR techniques (i.e. Small Baseline Subset and Persistent Scatterers techniques), available in SARscape software, are used. These methods involve the use of multiple acquisitions stacks (large SAR temporal series) allowing improvements and refinements in landslide identification, characterization and hazard evaluation at the basin scale. Potential and limits of above mentioned techniques are outlined and discussed. The study area is the Agno Valley, located in the North-Eastern sector of Italian Alps and included in the Vicenza Province (Veneto Region, Italy). This area and the entire Vicenza Province were hit by an exceptional rainfall event on November 2010 that triggered more than 500 slope instabilities. The main aim of the work is to verify if spatial information available before the rainfall event, including ERS and ENVISAT RADAR data from 1992 to 2010, were able to predict the landslides occurred in the study area, in order to implement an effectiveness forecasting model. In the first step of the work a susceptibility analysis is carried out using landslide dataset from the IFFI project (Inventario Fenomeni Franosi in Italia, Landslide Italian Inventory) and related predisposing factors, which consist of morphometric (elevation, slope, aspect and curvature) and non-morphometric (land use, distance of roads and distance of river) factors available from the Veneto Region spatial database. Then, to test the prediction, the

  3. On the Simulation of Floods in a Narrow Bending Valley: The Malpasset Dam Break Case Study

    Directory of Open Access Journals (Sweden)

    Chiara Biscarini

    2016-11-01

    Full Text Available In this paper, we investigate the performance of three-dimensional (3D hydraulic modeling when dealing with river sinuosity and meander bends. In river bends, the flow is dominated by a secondary current, which has a key role on the flow redistribution. The secondary flow induces transverse components of the bed shear stress and increases the velocity in outward direction, thus generating local erosion and riverbed modifications. When in river bends, the 3D processes prevail, and a 3D computational fluid dynamics (CFD model is required to correctly predict the flow structure. An accurate description of the different hydrodynamic processes in mildly and sharply curved bends find a relevant application in meanders migration modeling. The mechanisms that drive the velocity redistribution in meandering channels depend on the river’s roughness, the flow depth (H, the radius curvature (R, the width (B and the bathymetric variations. Here, the hydro-geomorphic characterization of sharp and mild meanders is performed by means of the ratios R/B, B/H, and R/H, and of the sinuosity index. As a case study, we selected the Malpasset dam break on the Reyran River Valley (FR, as it is perfectly suited for investigating performances and issues of a 3D model in simulating the inundation dynamics in a river channel with a varying curvature radius.

  4. A GIS-based model for the hydrological and hydraulic reconstruction of historical flash-floods in urban areas. The case of the river Turia in Valencia (1957)

    Science.gov (United States)

    Portugués Mollá, Iván; Felici, Xavier Bonache i.; Mateu Bellés, Joan F.; Segura, Juan B. Marco

    2015-04-01

    Flash-floods are recurrent events in the Mediterranean arch, mostly derived from cold air pool phenomena triggering hydro-geomorphic high-intensity processes, combining high discharge and low frequency. In urban environments the complexity of the processes become higher due to the existence of very fast-response basins and quick-response runoff. However, immediate activities of cleaning up and restoration delete the urban marks. After a short time both significance and dimension of the hydro-geomorphic event become completely unrecognizable. Nevertheless, these episodes generate extensive administrative documentation which is testimony of the processes in almost real time. Exploiting this source typology in order to reconstruct events far in time within urban areas, which may lack database sufficiently rich, is necessary to understand the hydrological and hydraulic derived processes. This is particularly the case of the Valencia flash-flood (1957), located in the lower Turia River basin (6.400 km2). Within a short interval (15 hours) there were registered two flood peaks (estimated at that time at 2.500 and 3.700 m3/s). The double overflowing inundated a large proportion of the urban area. The flash-flood activated fast processes with high energy that left numerous hydro-geomorphic marks. Although those tracks were deleted in a short while after the flood, it remains a legacy that had not yet been exploited, consisting of immediate aerial and oblique high resolution photography, pictures at street level, water level record and administrative records, such as claim files for compensation. Paradoxically, despite the event is considered as a milestone on metropolitan territorial planning and it was decided to divert the river Turia definitely through a major project (12 km of channeling, known as South Solution), being the scenario notably altered, the analysis of the hydrological and hydraulic process has never been reviewed. Undoubtedly, a modern study would ensure

  5. Flooding On

    Institute of Scientific and Technical Information of China (English)

    YIN PUMIN

    2010-01-01

    @@ Drenched riverside towns in central and south parts of China were preparing for even worse flooding as water levels in the country's huge rivers surged and rainstorms continued. As of July 27,accumulated precipitation since June 16 in 70 percent of the drainage areas of the Yangtze River had exceeded 50 mm,after three rounds of rainstorms,said Cai Qihua,Deputy Director of the Yangtze River Flood Control and Drought Relief Headquarters.

  6. Spatial variability and uncertainty in ecological risk assessment: a case study on the potential risk of cadmium for the little owl in a Dutch river flood plain.

    Science.gov (United States)

    Kooistra, Lammert; Huijbregts, Mark A J; Ragas, Ad M J; Wehrens, Ron; Leuven, Rob S E W

    2005-04-01

    This paper outlines a procedure that quantifies the impact of different sources of spatial variability and uncertainty on ecological risk estimates. The procedure is illustrated in a case study that estimates the risks of cadmium for a little owl (Athene noctua vidalli) living in a Dutch river flood plain along the river Rhine. A geographical information system (GIS) was used to quantify spatial variability in contaminant concentrations and habitats. It was combined with an exposure and effect model that uses Monte Carlo simulation to quantify parameter uncertainty. Spatial model uncertainty was assessed by the application of two different spatial interpolation methods (classification and kriging) and foraging ranges. The results of the case study show that parameter uncertainty is the main type of uncertainty influencing the risk estimate, and to a lesser extent spatial variability, while spatial model uncertainty was of minor importance. Compared to the deterministically calculated hazard index for the little owl (0.9), inclusion of spatial variability resulted in a median hazard index that can vary between 0.8 and 1.4. It is concluded that a single estimator for a whole flood plain may over- or underestimate risks for specific parts within the flood plain. Further research that expands the procedure presented in this paper is necessary to improve the incorporation of spatial factors in ecological risk assessment.

  7. Spatially distributed modelling of surface water-groundwater exchanges during overbank flood events - a case study at the Garonne River

    Science.gov (United States)

    Bernard-Jannin, Léonard; Brito, David; Sun, Xiaoling; Jauch, Eduardo; Neves, Ramiro; Sauvage, Sabine; Sánchez-Pérez, José-Miguel

    2016-08-01

    Exchanges between surface water (SW) and groundwater (GW) are of considerable importance to floodplain ecosystems and biogeochemical cycles. Flood events in particular are important for riparian water budget and element exchanges and processing. However SW-GW exchanges present complex spatial and temporal patterns and modelling can provide useful knowledge about the processes involved at the scale of the reach and its adjacent floodplain. This study used a physically-based, spatially-distributed modelling approach for studying SW-GW exchanges. The modelling in this study is based on the MOHID Land model, combining the modelling of surface water flow in 2D with the Saint-Venant equation and the modelling of unsaturated groundwater flow in 3D with the Richards' equation. Overbank flow during floods was also integrated, as well as water exchanges between the two domains across the entire floodplain. Conservative transport simulations were also performed to study and validate the simulation of the mixing between surface water and groundwater. The model was applied to the well-monitored study site of Monbéqui (6.6 km²) in the Garonne floodplain (south-west France) for a five-month period and was able to represent the hydrology of the study area. Infiltration (SW to GW) and exfiltration (SW to GW) were characterised over the five-month period. Results showed that infiltration and exfiltration exhibited strong spatiotemporal variations, and infiltration from overbank flow accounted for 88% of the total simulated infiltration, corresponding to large flood periods. The results confirmed that overbank flood events played a determinant role in floodplain water budget and SW-GW exchanges compared to smaller (below bankfull) flood events. The impact of floods on water budget appeared to be similar for flood events exceeding a threshold corresponding to the five-year return period event due to the study area's topography. Simulation of overbank flow during flood events was an

  8. Impact of agricultural management on pluvial flash floods - Case study of an extreme event observed in Austria in 2016

    Science.gov (United States)

    Lumassegger, Simon; Achleitner, Stefan; Kohl, Bernhard

    2017-04-01

    Central Europe was affected by extreme flash floods in summer 2016 triggered by short, high-intensity storm cells. Besides fluvial runoff, local pluvial floods appear to increase recently. In frame of the research project SAFFER-CC (sensitivity assessment of critical condition for local flash floods - evaluating the recurrence under climate change) surface runoff and pluvial flooding is assessed using a coupled hydrological/2D hydrodynamic model for the severely affected municipality of Schwertberg, Upper Austria. In this small catchment several flooding events occurred in the last years, where the most severe event occurred during summer 2016. Several areas could only be reached after the flood wave subsided with observed flood marks up to one meter. The modeled catchment is intensively cultivated with maize, sugar beets, winter wheat and soy on the hillside and hence highly vulnerable to water erosion. The average inclination is relatively steep with 15 % leading to high flow velocities of surface runoff associated with large amounts of transported sediments. To assess the influence of land use and soil conservation on flash floods, field experiments with a portable irrigation spray installation were carried out at different locations. The test plots were subjected to rainfall with constant intensity of 100 mm/h for one hour. Consecutively a super intense, one hour lasting, rainfall hydrograph was applied after 30 minutes at the same plots, ranging from 50 mm/h to 200 mm/h. Surface runoff was collected and measured in a tank and water samples were taken to determine the suspended material load. Large differences of runoff coefficients were determined depending on the agricultural management. The largest discharge was measured in a maize field, where surface runoff occurred immediately after start of irrigation. The determined runoff coefficients ranged from 0.22 for soy up to 0.65 for maize for the same soil type and inclination. The conclusion that runoff is

  9. A rainfall design method for spatial flood risk assessment: considering multiple flood sources

    Science.gov (United States)

    Jiang, X.; Tatano, H.

    2015-08-01

    Information about the spatial distribution of flood risk is important for integrated urban flood risk management. Focusing on urban areas, spatial flood risk assessment must reflect all risk information derived from multiple flood sources: rivers, drainage, coastal flooding etc. that may affect the area. However, conventional flood risk assessment deals with each flood source independently, which leads to an underestimation of flood risk in the floodplain. Even in floodplains that have no risk from coastal flooding, flooding from river channels and inundation caused by insufficient drainage capacity should be considered simultaneously. For integrated flood risk management, it is necessary to establish a methodology to estimate flood risk distribution across a floodplain. In this paper, a rainfall design method for spatial flood risk assessment, which considers the joint effects of multiple flood sources, is proposed. The concept of critical rainfall duration determined by the concentration time of flooding is introduced to connect response characteristics of different flood sources with rainfall. A copula method is then adopted to capture the correlation of rainfall amount with different critical rainfall durations. Rainfall events are designed taking advantage of the copula structure of correlation and marginal distribution of rainfall amounts within different critical rainfall durations. A case study in the Otsu River Basin, Osaka prefecture, Japan was conducted to demonstrate this methodology.

  10. A rainfall design method for spatial flood risk assessment: considering multiple flood sources

    Directory of Open Access Journals (Sweden)

    X. Jiang

    2015-08-01

    Full Text Available Information about the spatial distribution of flood risk is important for integrated urban flood risk management. Focusing on urban areas, spatial flood risk assessment must reflect all risk information derived from multiple flood sources: rivers, drainage, coastal flooding etc. that may affect the area. However, conventional flood risk assessment deals with each flood source independently, which leads to an underestimation of flood risk in the floodplain. Even in floodplains that have no risk from coastal flooding, flooding from river channels and inundation caused by insufficient drainage capacity should be considered simultaneously. For integrated flood risk management, it is necessary to establish a methodology to estimate flood risk distribution across a floodplain. In this paper, a rainfall design method for spatial flood risk assessment, which considers the joint effects of multiple flood sources, is proposed. The concept of critical rainfall duration determined by the concentration time of flooding is introduced to connect response characteristics of different flood sources with rainfall. A copula method is then adopted to capture the correlation of rainfall amount with different critical rainfall durations. Rainfall events are designed taking advantage of the copula structure of correlation and marginal distribution of rainfall amounts within different critical rainfall durations. A case study in the Otsu River Basin, Osaka prefecture, Japan was conducted to demonstrate this methodology.

  11. River channel network design for drought and flood control: A case study of Xiaoqinghe River basin, Jinan City, China.

    Science.gov (United States)

    Cui, Baoshan; Wang, Chongfang; Tao, Wendong; You, Zheyuan

    2009-08-01

    Vulnerability of river channels to urbanization has been lessened by the extensive construction of artificial water control improvements. The challenge, however, is that traditional engineering practices on isolated parts of a river may disturb the hydrologic continuity and interrupt the natural state of ecosystems. Taking the Xiaoqinghe River basin as a whole, we developed a river channel network design to mitigate river risks while sustaining the river in a state as natural as possible. The river channel risk from drought during low-flow periods and flood during high-flow periods as well as the potential for water diversion were articulated in detail. On the basis of the above investigation, a network with "nodes" and "edges" could be designed to relieve drought hazard and flood risk respectively. Subsequently, the shortest path algorithm in the graph theory was applied to optimize the low-flow network by searching for the shortest path. The effectiveness assessment was then performed for the low-flow and high-flow networks, respectively. For the former, the network connectedness was evaluated by calculating the "gamma index of connectivity" and "alpha index of circuitry"; for the latter, the ratio of flood-control capacity to projected flood level was devised and calculated. Results show that the design boosted network connectivity and circuitry during the low-flow periods, indicating a more fluent flow pathway, and reduced the flood risk during the high-flow periods.

  12. Flood prevention dams for arid regions at a micro-scale sub-catchment, case study: Tabuk, Saudi Arabia.

    Science.gov (United States)

    Abushandi, Eyad

    2016-12-01

    Unexpected flash flooding is one of the periodic hydrological problems affecting the city of Tabuk in Saudi Arabia. The region has high potential for floods as it suffers high rainfall intensity in a short time and also has high urbanization rates and topographic complexity. Constructing flood prevention dams is one option to solve this problem. A cost-effective design requires a detailed feasibility study and analysis for the selection of suitable sites. The aim of this study was to develop a method for selecting a suitable site for flood protection dams in the Abu Saba'a district, the most affected part of the city of Tabuk during the flash flood in January 2013. Spatial analysis was applied using Landsat Thematic Mapper images and Shuttle Radar Topography Mission digital elevation model to select a site in the Abu Saba'a area. A simple model using ArcGIS was built including all suggested parameters. The results showed the best site for a dam was 2 km distance backfrom the area, where all parameter values matched. The results showed that the dynamic properties of land cover can affect site selection. It is therefore suggested that more field and hydrological data should be gathered for greater accuracy.

  13. Numerical Simulation of Downstream Flooding due to a Flexible-Dam Collapse. The case of "La Esperanza" dam, Hidalgo-México: Implication on Hazard Assessment.

    Science.gov (United States)

    Areu Rangel, O. S., Sr.; Mendoza-Sanchez, I.; Bonasia, R.

    2015-12-01

    The risk of flooding of settlements located downstream of a dam is high due to the large number of people living on natural waterways. Risk assessment of flooding could help in projecting containment and protection in case of a dam-break. For projecting containment and protection works, the assessment should take into account velocities, densities and impact pressure of the water on the villages in risk. Therefore, it is appealing to conduct a series of numerical simulations of downstream flooding including velocity and pressure fields, and their temporal and spatial fluctuations. The present work focuses on the real case of "La Esperanza" dam, located in the state of Hidalgo (Mexico). The dam was built 70 years ago and currently two thirds of its capacity is covered with silt, which implies a very high horizontal thrust. The simulation of the flood due to failure of the dam was carried on using the DualSPHysics code, a new implementation of the mesh-free Lagrangian Smoothed Particle Hydrodynamic (SPH) method. For the boundary conditions, a Digital Elevation Model of the potentially affected area was built using satellite images, the actual bathymetry of the dam and cross sections of the channel. In order to evaluate the hazard posed to the villages located downstream of the dam, different collapse scenarios were simulated, with particular focus on the consequences of the temporal variation of rainfall. Preliminary results show acceleration and dynamic pressure values of water in especially selected areas that are subjected to high risk for the elevated number of inhabitant.

  14. The economic dimensions of integrating flood management and agri-environment through washland creation: a case from Somerset, England.

    Science.gov (United States)

    Morris, J; Bailey, A P; Lawson, C S; Leeds-Harrison, P B; Alsop, D; Vivash, R

    2008-07-01

    In many river floodplains in the UK, there has been a long history of flood defence, land reclamation and water regime management for farming. In recent years, however, changing European and national policies with respect to farming, environment and flood management are encouraging a re-appraisal of land use in rural areas. In particular, there is scope to develop, through the use of appropriate promotional mechanisms, washland areas, which will simultaneously accommodate winter inundation, support extensive farming methods, deliver environmental benefits, and do this in a way which can underpin the rural economy. This paper explores the likely economic impacts of the development of flood storage and washland creation. In doing so, consideration is given to feasibility of this type of development, the environmental implications for a variety of habitats and species, and the financial and institutional mechanisms required to achieve implementation.

  15. A study of different cases of VVER reactor core flooding in a large break loss of coolant accident

    Directory of Open Access Journals (Sweden)

    Bezrukov Yury Alekseevich

    2016-01-01

    Full Text Available The paper covers the results of VVER core reflooding studies in fuel assembly (FA mockup of 126 fuel rod simulators with axial power peaking. The experiments were performed for two types of flooding. The first type is top flooding of the empty (steamed FA mockup. The second type is bottom flooding of the FA mockup with level of boiling water. The test parameters are as follows: the range of the supplied power to the bundle is from 40 to 320 kW, the cooling water flow rate is from 0.04 to 1.1 kg/s, the maximum temperature of the fuel rod simulator is 800 °C and the linear heat flux is from 0.1 to 1.0 kW/m. The test results were used for computer code validation.

  16. Conveying Flood Hazard Risk Through Spatial Modeling: A Case Study for Hurricane Sandy-Affected Communities in Northern New Jersey

    Science.gov (United States)

    Artigas, Francisco; Bosits, Stephanie; Kojak, Saleh; Elefante, Dominador; Pechmann, Ildiko

    2016-10-01

    The accurate forecast from Hurricane Sandy sea surge was the result of integrating the most sophisticated environmental monitoring technology available. This stands in contrast to the limited information and technology that exists at the community level to translate these forecasts into flood hazard levels on the ground at scales that are meaningful to property owners. Appropriately scaled maps with high levels of certainty can be effectively used to convey exposure to flood hazard at the community level. This paper explores the most basic analysis and data required to generate a relatively accurate flood hazard map to convey inundation risk due to sea surge. A Boolean overlay analysis of four input layers: elevation and slope derived from LiDAR data and distances from streams and catch basins derived from aerial photography and field reconnaissance were used to create a spatial model that explained 55 % of the extent and depth of the flood during Hurricane Sandy. When a ponding layer was added to the previous model to account for depressions that would fill and spill over to nearby areas, the new model explained almost 70 % of the extent and depth of the flood. The study concludes that fairly accurate maps can be created with readily available information and that it is possible to infer a great deal about risk of inundation at the property level, from flood hazard maps. The study goes on to conclude that local communities are encouraged to prepare for disasters, but in reality because of the existing Federal emergency management framework there is very little incentive to do so.

  17. Influence of deposition of fine plant debris in river floodplain shrubs on flood flow conditions - The Warta River case study

    Science.gov (United States)

    Mazur, Robert; Kałuża, Tomasz; Chmist, Joanna; Walczak, Natalia; Laks, Ireneusz; Strzeliński, Paweł

    2016-08-01

    This paper presents problems caused by organic material transported by flowing water. This material is usually referred to as plant debris or organic debris. Its composition depends on the characteristic of the watercourse. For lowland rivers, the share of the so-called small organic matter in plant debris is considerable. This includes both various parts of water plants and floodplain vegetation (leaves, stems, blades of grass, twigs, etc.). During floods, larger woody debris poses a significant risk to bridges or other water engineering structures. It may cause river jams and may lead to damming of the flowing water. This, in turn, affects flood safety and increases flood risk in river valleys, both directly and indirectly. The importance of fine plant debris for the phenomenon being studied comes down to the hydrodynamic aspect (plant elements carried by water end up on trees and shrubs, increase hydraulic flow resistance and contribute to the nature of flow through vegetated areas changed from micro-to macro-structural). The key part of the research problem under analysis was to determine qualitative and quantitative debris parameters and to establish the relationship between the type of debris and the type of land use of river valleys (crop fields, meadows and forested river sections). Another problem was to identify parameters of plant debris for various flow conditions (e.g. for low, medium and flood flows). The research also included an analysis of the materials deposited on the structure of shrubs under flood flow conditions during the 2010 flood on the Warta River.

  18. Conveying Flood Hazard Risk Through Spatial Modeling: A Case Study for Hurricane Sandy-Affected Communities in Northern New Jersey.

    Science.gov (United States)

    Artigas, Francisco; Bosits, Stephanie; Kojak, Saleh; Elefante, Dominador; Pechmann, Ildiko

    2016-10-01

    The accurate forecast from Hurricane Sandy sea surge was the result of integrating the most sophisticated environmental monitoring technology available. This stands in contrast to the limited information and technology that exists at the community level to translate these forecasts into flood hazard levels on the ground at scales that are meaningful to property owners. Appropriately scaled maps with high levels of certainty can be effectively used to convey exposure to flood hazard at the community level. This paper explores the most basic analysis and data required to generate a relatively accurate flood hazard map to convey inundation risk due to sea surge. A Boolean overlay analysis of four input layers: elevation and slope derived from LiDAR data and distances from streams and catch basins derived from aerial photography and field reconnaissance were used to create a spatial model that explained 55 % of the extent and depth of the flood during Hurricane Sandy. When a ponding layer was added to the previous model to account for depressions that would fill and spill over to nearby areas, the new model explained almost 70 % of the extent and depth of the flood. The study concludes that fairly accurate maps can be created with readily available information and that it is possible to infer a great deal about risk of inundation at the property level, from flood hazard maps. The study goes on to conclude that local communities are encouraged to prepare for disasters, but in reality because of the existing Federal emergency management framework there is very little incentive to do so.

  19. Development of a smart flood warning system in urban areas: A case study of Huwei area in Taiwan

    Science.gov (United States)

    Yang, Sheng-Chi; Hsu, Hao-Ming; Kao, Hong-Ming

    2016-04-01

    In this study, we developed a smart flood warning system to clearly understand flood propagations in urban areas. The science and technology park of Huwei, located in the southwest of Taiwan, was selected as a study area. It was designated to be an important urban area of optoelectronics and biotechnology. The region has an area about 1 km2 with approximately 1 km in both length and width. The discrepancy between the highest and lowest elevations is 6.3 m and its elevation decreases along the northeast to the southwest. It is an isolated urban drainage area due to its urban construction plan. The storm sewer system in this region includes three major networks that collect the runoff and drain to the detention pond where is located in the southwest corner of the region. The proposed smart flood warning system combines three important parts, i.e. the physical world, the cyber-physical interface, and the cyber space, to identify how the flood affects urban areas from now until the next three hours. In the physical world, when a rainfall event occurs, monitoring sensors (e.g. rainfall gauges and water level gauges built in the sewer system and ground surface), which are established in several essential locations of the study area, collect in situ hydrological data and then these data being transported to the cyber-physical interface. The cyber-physical interface is a data preprocess space that includes data analysis, quality control and assurance, and data integration and standardization to produce the validated data. In the cyber space, it has missions to receive the validated data from the cyber-physical interface and to run the time machine that has flood analyses of data mining, inundation scenarios simulation, risk and economic assessments, and so on, based on the validated data. After running the time machine, it offers the analyzed results related to flooding planning, mitigation, response, and recovery. According to the analyzed results, the decision supporting

  20. Urban Flood Mapping Based on Unmanned Aerial Vehicle Remote Sensing and Random Forest Classifier—A Case of Yuyao, China

    Directory of Open Access Journals (Sweden)

    Quanlong Feng

    2015-03-01

    Full Text Available Flooding is a severe natural hazard, which poses a great threat to human life and property, especially in densely-populated urban areas. As one of the fastest developing fields in remote sensing applications, an unmanned aerial vehicle (UAV can provide high-resolution data with a great potential for fast and accurate detection of inundated areas under complex urban landscapes. In this research, optical imagery was acquired by a mini-UAV to monitor the serious urban waterlogging in Yuyao, China. Texture features derived from gray-level co-occurrence matrix were included to increase the separability of different ground objects. A Random Forest classifier, consisting of 200 decision trees, was used to extract flooded areas in the spectral-textural feature space. Confusion matrix was used to assess the accuracy of the proposed method. Results indicated the following: (1 Random Forest showed good performance in urban flood mapping with an overall accuracy of 87.3% and a Kappa coefficient of 0.746; (2 the inclusion of texture features improved classification accuracy significantly; (3 Random Forest outperformed maximum likelihood and artificial neural network, and showed a similar performance to support vector machine. The results demonstrate that UAV can provide an ideal platform for urban flood monitoring and the proposed method shows great capability for the accurate extraction of inundated areas.

  1. High-frequency sea level variations and implications for coastal flooding: A case study of the Solent, UK

    Science.gov (United States)

    Ozsoy, Ozgun; Haigh, Ivan D.; Wadey, Matthew P.; Nicholls, Robert J.; Wells, Neil C.

    2016-07-01

    This study examines the occurrence and characteristics of high-frequency (energy events have a mean amplitude of approximately 0.6 m and a dominant period of around 4 h. These events correspond with periods of enhanced meteorological activity, namely a marked reduction in air pressure and onset of strong southwesterly-southeasterly winds. Sea level observations from tide gauges around the Solent and the wider English Channel region (23 in total) were used to assess the spatial characteristics of these events. Analysis of time series and phase information indicates the occurrence of standing waves oscillating across the English Channel between southern England and northern France. This study provides a unique example of standing waves generated by extra-tropical cyclones over a large basin (the English Channel) with implications for flood inundation. The event of 28th October 2013 - the highest-amplitude (1.16 m) event in the record - was associated with minor coastal flooding at Yarmouth, Isle of Wight. This flood occurred during a neap tide, when such events are widely thought to be impossible. Hence, our findings emphasize the relevance of high-frequency sea level variability for regional sea level forecasting and flood risk management.

  2. The use of radar in hydrological modeling in the Czech Republic – case studies of flash floods

    Directory of Open Access Journals (Sweden)

    M. Šálek

    2006-01-01

    Full Text Available Flash flood induced by severe convection is the hydrometeorological phenomenon that is very difficult to forecast. However, the implementation of radar measurements, especially radar-based Quantitative Precipitation Estimate (QPE and/or radar-based quantitative Precipitation Nowcast (QPN can improve this situation. If the radar is able to capture the development of severe convection and can produce reasonably accurate QPE in short time intervals (e.g. 10 min, then it can be used also with hydrological model. A hydrological model named Hydrog was used for investigation of simulation and possible forecasts of two flash floods that took place in the Czech Republic in 2002 and 2003. The precipitation input consisted of mean-field-bias-adjusted or original radar 10-min estimates along with quantitative precipitation nowcasts up to 2 h based on COTREC method (extrapolation. Taking into account all the limited predictability of the severe convection development and the errors of the radar-based precipitation estimates, the aim of the simulations was to find out to what extend the hydrometeorological prediction system, specifically tuned for these events, was able to forecast a the flash floods. As assumed, the hydrometeorological simulations of the streamflow forecasts lagged behind the actual development but there is still some potential for successful warning, especially for areas where the flood hits lately.

  3. Mesoscale aspects of storms producing floods over regions of arid mountainous terrain

    Science.gov (United States)

    Houze, R.; Romatschke, U.; Rasmussen, K. L.

    2011-12-01

    We have used the TRMM satellite's Precipitation Radar (PR) to develop a climatology of extreme convection in the regions of the Andes and Himalayas. This work shows that intense convection often occurs in arid regions but does not usually produce large amounts of rain. Large quantities of rain falling in mountainous regions is associated with the convective systems that have the greatest horizontal scales. When such wide systems occur over arid mountains, they can produce lethal floods. The Pakistan flood of 2010 is a case in point. Wide convective systems with large stratiform components became situated over the arid mountains of that region, with the result of the Indus River overflowed with disastrous consequences over a huge area. The potential of heavy rain in the region could have been inferred from the forecast synoptic-scale circulation, which indicated the occurrence of a great buildup of moisture in the region. Although the synoptic conditions were well forecast, that information alone was insufficient for predicting the flood conditions. It would have been necessary to anticipate also the mesoscale structure of the storms. Our TRMM satellite climatology of rainstorm structures in this region indicated that the mesoscale convective rainstorms responsible for the floods were of a type that does not normally occur in this region. Rather, this type of storm usually occurs and produces copious monsoon rain far to the east, over the mountains and wetlands of northeastern India and Bangladesh. In this event, catastrophic runoff and flooding resulted as these rainstorms occurred far to the west of where they usually occur, over an arid and mountainous region unaccustomed to such storms. This study indicates that taking into account the mesoscale structures of the cloud systems as well as the synoptic conditions in which they are embedded is essential for forecasting floods in this region of complex terrain.

  4. Combating Floods

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    In summer and autumn of 1998, the river vatleys of the Changjiang, Songhua and Nenjiang rivers were stricken by exceptionally serious floods, As of the, 22nd of August, the flooded areas stretched over 52.4 million acres. More than 223 million people were affected by the flood. 4.97 million houses were ruined, economic losses totaled RMB 166 billion, and most tragically, 3,004 people lost their byes. It was one of the costliest disasters in Chinese history. Millions of People’s Liberation Army soldiers and local people joined hands to battle the floodwaters. Thanks to their unified efforts and tenacious struggle, they successfully withstood the rising, water, resumed production and began to rebuild their homes.

  5. A case of leucism in House Sparrow, Passer domesticus (Linnaeus, 1758 in an island of São Francisco river, northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Leonardo Barros Ribeiro

    2012-03-01

    Full Text Available Leucism in birds is a genetic disorder characterized by the total absence of melanin in some or all feathers, but unlike albinism, the other body parts, such as eyes, beak, and tarsi remain with the typical color of the species. The House Sparrow Passer domesticus is a bird native from Europe, Asia, and North Africa. It has been introduced in North America, South America, South Africa, Australia, and New Zealand. Currently, it is the bird species with the largest geographical range. Here, we report the record of a leucistic specimen of Passer domesticus from Rodeadouro island, São Francisco river, northeastern Brazil.

  6. Migratory flows and foraging habitat selection by shorebirds along the northeastern coast of Brazil: The case of Baía de Todos os Santos

    Science.gov (United States)

    Lunardi, Vitor O.; Macedo, Regina H.; Granadeiro, José P.; Palmeirim, Jorge M.

    2012-01-01

    Large numbers of Nearctic shorebirds migrate and winter along the coast of northeastern Brazil, but there is little information on their migratory flows, foraging ecology, and on the structure of the species assemblages that they form with resident shorebirds. We studied these issues on intertidal flats of Baía de Todos os Santos (Bahia), the second largest bay in Brazil. During a full year cycle we carried out weekly bird counts in an intertidal area of 280 ha divided in sectors, where we also measured environmental parameters. The analyses of weekly counts resulted in a detailed phenology of use of the area by shorebirds. Five species were resident and ten were Nearctic migrants. Several of the latter had clear peaks in numbers in March and October, revealing the use of the bay as a stopover during both the north-bound and south-bound migration flows. A canonical correspondence analysis of the relationship between environmental parameters and bird numbers indicated that the foraging bird assemblage could be divided into five main groups, occupying distinct ecological gradients in the study area. The most important factors driving this structure were invertebrate prey abundance, percentage of fine sediments, area of mangrove cover and distance to channels. Our findings imply that maintenance of the diversity of intertidal habitats in this bay is crucial to satisfy the particular habitat requirements of resident and migrant shorebirds using the northeastern coastal regions of Brazil.

  7. Flooding On

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Drenched riverside towns in central and south parts of China were preparing for even worse flooding aswater levels in the country’s huge rivers surged and rainstorms continued.As of July 27,accumulated precipitation since June 16 in 70 percent of the drainage

  8. Brief Communication: An update of the article "Modelling flood damages under climate change conditions - a case study for Germany"

    Science.gov (United States)

    Fokko Hattermann, Fred; Huang, Shaochun; Burghoff, Olaf; Hoffmann, Peter; Kundzewicz, Zbigniew W.

    2016-07-01

    In our first study on possible flood damages under climate change in Germany, we reported that a considerable increase in flood-related losses can be expected in a future warmer climate. However, the general significance of the study was limited by the fact that outcome of only one global climate model (GCM) was used as a large-scale climate driver, while many studies report that GCMs are often the largest source of uncertainty in impact modelling. Here we show that a much broader set of global and regional climate model combinations as climate drivers show trends which are in line with the original results and even give a stronger increase of damages.

  9. Assessment of the warning system against floods on a rural area: the case of the lower Siret River (Romania

    Directory of Open Access Journals (Sweden)

    F. Salit

    2013-02-01

    Full Text Available The development of non-structural measures such as an early warning system, across the Europe, in flood risk management, requires a better understanding of the public involved and of the territory threatened. This paper aims to conduct an assessment of early warning and information to people with an analysis of the population's behaviour, presented in a form of an event tree. The objective is to understand the strengths and weaknesses of the warning system during a deadly flood in the lower Siret River (Romania in 2005 and to demonstrate that each warning system has to be adapted to the territory in which it is effective. The behavioural model aims to determine to what extent the warning system can be improved but also to suggest ways to adapt risk education to the study area.

  10. Flood resilience urban territories. Flood resilience urban territories.

    Science.gov (United States)

    Beraud, Hélène; Barroca, Bruno; Hubert, Gilles

    2010-05-01

    The flood's impact during the last twenty years on French territory reveals our lack of preparation towards large-extended floods which might cause the stopping of companies' activity, services, or lead to housing unavailability during several months. New Orleans' case has to exemplify us: four years after the disaster, the city still couldn't get back its dynamism. In France, more than 300 towns are flood-exposed. While these towns are the mainspring of territory's development, it is likely that the majority of them couldn't get up quickly after a large-extended flood. Therefore, to understand and improve the urban territory's resilience facing floods is a real stake for territory's development. Urban technical networks supply, unify and irrigate all urban territories' constituents. Characterizing their flood resilience can be interesting to understand better urban resilience. In this context, waste management during and after floods is completely crucial. During a flood, the waste management network can become dysfunctional (roads cut, waste storage installations or waste treatment flooded). How can the mayor respect his obligation to guarantee salubrity and security in his city? In post flood the question is even more problematic. The waste management network presents a real stake for territory's restart. After a flood, building materials, lopped-of branches, furniture, business stocks, farm stocks, mud, rubbles, animal cadavers are wet, mixed, even polluted by hydrocarbons or toxic substances. The waste's volume can be significant. Sanitary and environmental risks can be crucial. In view of this situation, waste's management in post crisis period raises a real problem. What to make of this waste? How to collect it? Where to stock it? How to process it? Who is responsible? Answering these questions is all the more strategic since this waste is the mark of disaster. Thus, cleaning will be the first population's and local actor's reflex in order to forget the

  11. Flood Prevention and Sustainable Spatial Planning. The Case of the River Diakoniaris in Patras Authors: D. Vespiniadou, E. Athanasopoulou

    OpenAIRE

    2006-01-01

    The danger of floods from overflow of rivers that crosses urban regions is a frequent phenomenon that concerns many of European countries. In the framework of Sustainable Spatial Planning arise some serious questions for the way that should such phenomena be handled, apart from the purely hydraulic conventional interventions. Noteworthy that at his flow a river runs through usually at all the length completely dissimilar regions as long as they concern in geomorphology but also their urban ch...

  12. Community vulnerability assessment index for flood prone savannah agro-ecological zone: A case study of Wa West District, Ghana

    Directory of Open Access Journals (Sweden)

    Effah Kwabena Antwi

    2015-12-01

    Full Text Available The savannah regions of Northern Ghana are characterized by smallholder farming systems and high levels of poverty. Over the past two decades, communities in the regions have become more prone to climate and human-induced disasters in the form of annual floods and droughts. This study evaluates the degree and magnitude of vulnerability in four communities subjected to similar climate change induced flood events and propose intervention options. The study employs rural participatory research approaches in developing four vulnerability categories namely socio-economic, ecological, engineering and political; which were used to develop indicators that aided the calculation of total community vulnerability index for each community. The findings indicate that the state of a community's vulnerability to flood is a composite effect of the four vulnerability index categories which may act independently or concurrently to produce the net effect. Based on a synthesis of total vulnerability obtained in each community, Baleufili was found to be the least vulnerable to flood due to its high scores in engineering, socio-economic and political vulnerability indicators. Baleufili and Bankpama were the most ecologically vulnerable communities. The selection of vulnerability index categories and associated indicators were grounded in specific local peculiarities that evolved out of engagement with community stakeholders and expert knowledge of the socioecological landscape. Thus, the Total Community Vulnerability Assessment Framework (TCVAF provides an effective decision support for identifying communities’ vulnerability status and help to design both short and long term interventions options that are community specific as a way of enhancing their coping and adaptive capacity to disasters.

  13. Investigating extreme flood response to Holocene palaeoclimate in the Chinese monsoonal zone: A palaeoflood case study from the Hanjiang River

    Science.gov (United States)

    Guo, Yongqiang; Huang, Chun Chang; Pang, Jiangli; Zha, Xiaochun; Zhou, Yali; Wang, Longsheng; Zhang, Yuzhu; Hu, Guiming

    2015-06-01

    Palaeoflood events recorded by slackwater deposits (SWDs) were investigated extensively by sedimentological criteria of palaeohydrology along the upper Hanjiang River valley. Modern flood SWDs were collected for comparison with palaeoflood SWD in the same reaches. Three typical palaeoflood SWDs were observed within Holocene loess-soil blanket on the first river terrace land. The grain size distributions of palaeoflood SWDs are similar to modern flood SWDs, whereas they are different from eolian loess and soil. Palaeoflood SWD lies in three major pedo-stratigraphic boundaries (TS/L0, L0/S0, and S0/Lt) in the Holocene loess-soil profiles. The chronology of three palaeoflood episodes was established by OSL dating and pedo-stratigraphic correlation with the well-dated Holocene loess-soil profiles in the upper Hanjiang River basin. Holocene palaeoflood events were dated to 9500-8500, 3200-2800, and 1800-1700 a B.P., respectively. Palaeoflood discharges were estimated by the palaeoflood model (i.e., slope-area method and step-backwater method). The highest discharges are 51,680-53,950 m3 s- 1 at the 11,500-time scale in the Xunyang reach of the upper Hanjiang River valley. Holocene extraordinary hydroclimatic events in the Hanjiang River often result from abnormal atmospheric circulations from Southwest monsoons in the Chinese monsoonal zone. These results provide a regional expression of extreme flood response to Holocene palaeoclimate to understand the effects of global climatic variations on the river system dynamics.

  14. Study of impacts of floods on the water quality in an arid zone: the case of the Tarim River in Northwest China.

    Science.gov (United States)

    Jean de la Paix, Mupenzi; Lanhai, Li; Xi, Chen; Varenyam, Achal; Anming, Bao

    2011-01-01

    This paper presents the results of the study undertaken at the Tarim River Basin in Northwest China to analyze impacts of flooding on water quality. It was shown that irregular rainfall was the cause of flash floods that affected many ecosystems and eroded soils. Simulation results and the existence of relationships between flood volume and flood peak allowed potential model application that included flood peak estimation. The analysis of water pollution through sample sediment was helped by spectroscopy techniques and it was found that the flood was the main cause of many chemical elements in water. The floods affected the quality of water in the Tarim River where it was slightly basic with pH = 8.1 before flooding and acidic with pH = 6.9 after flooding.

  15. How to update design floods after the construction of small reservoirs and check dams: A case study from the Daqinghe river basin, China

    Science.gov (United States)

    Li, Jianzhu; Sun, Huafeng; Feng, Ping

    2016-06-01

    Several small reservoirs and a large number of check dams had been constructed in the Wangkuai reservoir watershed after 1970s, and flood time series lacked stationarity, which affected the original design flood hydrographs for the Wangkuai reservoir. Since the location, storage capacity and drainage area of the large number of check dams were unknown, we present a method to estimate their total storage capacities (TSC) and total drainage areas (TDA) by using the recorded rainstorm and flood data. On the basis of TSC and TDA, the flood events which occurred in an undisturbed period were reconstructed under current conditions to obtain a stationary flood series. A frequency analysis was subsequently performed to assess the design flood peak and volume for both small and medium design floods with a 10-200 year return period. For large and catastrophic floods, it was assumed that the upstream check dams and small reservoirs would be destroyed, and water stored in these hydraulic structures were re-routed to the Wangkuai reservoir by unit hydrograph. The modified flood peak and volume decreased for floods with a 10-200 year return period when compared to the current design flood. But for large design floods with a return period exceeding 500 years, peak discharge increased. This study provides a new method for design flood calculation or modification of the original design flood in watersheds with a large number of check dams.

  16. Tangible and Intangible Flood damage evaluation

    Directory of Open Access Journals (Sweden)

    Frongia Sara

    2016-01-01

    Full Text Available Flooding and flash floods that cause significant economic and social damage have been widely studied in the last few decades. The European Commission Flood Directive 2007/60 Flood Risk Management Plans require the assessment of potential damage to give an appreciation of the magnitude of the consequences of a flood event and so help stakeholders to use a cost benefit approach to planning flood mitigation measures. This paper evaluates the direct tangible flood damage applying the JRC water depth-damage functions for the European territory to estimate the potential economic damage. Intangible damage is evaluated with the Life Safety Model (LSM to study the dynamic interactions among people, vehicles, buildings and the flood wave. LSM assesses potential flood damage and allows the development of a Flood Evacuation Plan in case of an emergency, underlining the evacuation routes adopted by people and vehicles. This enables emergency managers to avoid evacuation bottleneck problems and identify areas of potential high mortality. The impact of changes such as road network improvements, the location of safe havens and timing of flood warnings can be assessed in terms of potential loss of life. The developed methodology has been applied on the Sardinian Flood Risk Management Plan pilot basin, the Coghinas river lowland basin.

  17. Tsunami flooding

    Science.gov (United States)

    Geist, Eric; Jones, Henry; McBride, Mark; Fedors, Randy

    2013-01-01

    Panel 5 focused on tsunami flooding with an emphasis on Probabilistic Tsunami Hazard Analysis (PTHA) as derived from its counterpart, Probabilistic Seismic Hazard Analysis (PSHA) that determines seismic ground-motion hazards. The Panel reviewed current practices in PTHA and determined the viability of extending the analysis to extreme design probabilities (i.e., 10-4 to 10-6). In addition to earthquake sources for tsunamis, PTHA for extreme events necessitates the inclusion of tsunamis generated by submarine landslides, and treatment of the large attendant uncertainty in source characterization and recurrence rates. Tsunamis can be caused by local and distant earthquakes, landslides, volcanism, and asteroid/meteorite impacts. Coastal flooding caused by storm surges and seiches is covered in Panel 7. Tsunamis directly tied to earthquakes, the similarities with (and path forward offered by) the PSHA approach for PTHA, and especially submarine landslide tsunamis were a particular focus of Panel 5.

  18. How to update design floods after the construction of small reservoirs and check dams: A case study from the Daqinghe river basin, China

    Indian Academy of Sciences (India)

    Jianzhu Li; Huafeng Sun; Ping Feng

    2016-06-01

    Several small reservoirs and a large number of check dams had been constructed in theWangkuai reservoirwatershed after 1970s, and flood time series lacked stationarity, which affected the original design floodhydrographs for the Wangkuai reservoir. Since the location, storage capacity and drainage area of thelarge number of check dams were unknown, we present a method to estimate their total storage capacities(TSC) and total drainage areas (TDA) by using the recorded rainstorm and flood data. On the basisof TSC and TDA, the flood events which occurred in an undisturbed period were reconstructed undercurrent conditions to obtain a stationary flood series. A frequency analysis was subsequently performedto assess the design flood peak and volume for both small and medium design floods with a 10–200year return period. For large and catastrophic floods, it was assumed that the upstream check dams andsmall reservoirs would be destroyed, and water stored in these hydraulic structures were re-routed to theWangkuai reservoir by unit hydrograph. The modified flood peak and volume decreased for floods witha 10–200 year return period when compared to the current design flood. But for large design floods witha return period exceeding 500 years, peak discharge increased. This study provides a new method fordesign flood calculation or modification of the original design flood in watersheds with a large numberof check dams.

  19. Development of a flood early warning system and communication with end-users: the Vipava/Vipacco case study in the KULTURisk FP7 project

    Science.gov (United States)

    Grossi, Giovanna; Caronna, Paolo; Ranzi, Roberto

    2014-05-01

    Within the framework of risk communication, the goal of an early warning system is to support the interaction between technicians and authorities (and subsequently population) as a prevention measure. The methodology proposed in the KULTURisk FP7 project aimed to build a closer collaboration between these actors, in the perspective of promoting pro-active actions to mitigate the effects of flood hazards. The transnational (Slovenia/ Italy) Soča/Isonzo case study focused on this concept of cooperation between stakeholders and hydrological forecasters. The DIMOSHONG_VIP hydrological model was calibrated for the Vipava/Vipacco River (650 km2), a tributary of the Soča/Isonzo River, on the basis of flood events occurred between 1998 and 2012. The European Centre for Medium-Range Weather Forecasts (ECMWF) provided the past meteorological forecasts, both deterministic (1 forecast) and probabilistic (51 ensemble members). The resolution of the ECMWF grid is currently about 15 km (Deterministic-DET) and 30 km (Ensemble Prediction System-EPS). A verification was conducted to validate the flood-forecast outputs of the DIMOSHONG_VIP+ECMWF early warning system. Basic descriptive statistics, like event probability, probability of a forecast occurrence and frequency bias were determined. Some performance measures were calculated, such as hit rate (probability of detection) and false alarm rate (probability of false detection). Relative Opening Characteristic (ROC) curves were generated both for deterministic and probabilistic forecasts. These analysis showed a good performance of the early warning system, in respect of the small size of the sample. A particular attention was spent to the design of flood-forecasting output charts, involving and inquiring stakeholders (Alto Adriatico River Basin Authority), hydrology specialists in the field, and common people. Graph types for both forecasted precipitation and discharge were set. Three different risk thresholds were identified

  20. Exploration of land-use scenarios for flood hazard modeling – the case of Santiago de Chile

    Directory of Open Access Journals (Sweden)

    A. Müller

    2011-04-01

    Full Text Available Urban expansion leads to modifications in land use and land cover and to the loss of vegetated areas. These developments are in some regions of the world accelerated by a changing regional climate. As a consequence, major changes in the amount of green spaces can be observed in many urban regions. Amongst other dependences the amount of green spaces determines the availability of retention areas in a watershed. The goal of this research is to develop possible land-use and land-cover scenarios for a watershed and to explore the influence of land-use and land-cover changes on its runoff behavior using the distributed hydrological model HEC-HMS. The study area for this research is a small peri-urban watershed in the eastern area of Santiago de Chile.

    Three spatially explicit exploratory land-use/land-cover scenario alternatives were developed based on the analysis of previous land-use developments using high resolution satellite data, on the analysis of urban planning laws, on the analysis of climate change predictions, and on expert interviews. Modeling the resulting changes in runoff allows making predictions about the changes in flood hazard which the adjacent urban areas are facing after heavy winter precipitation events. The paper shows how HEC-HMS was used applying a distributed event modeling approach. The derived runoff values are combined with existing flood hazard maps and can be regarded as important source of information for the adaptation to changing conditions in the study area. The most significant finding is that the land-use changes that have to be expected after long drought periods pose the highest risk with respect to floods.

  1. Flood susceptibility assessment in a highly urbanized alluvial fan: the case study of Sala Consilina (southern Italy

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    N. Santangelo

    2011-10-01

    Full Text Available This paper deals with the risk assessment to alluvial fan flooding at the piedmont zone of carbonate massifs of the southern Apennines chain (southern Italy. These areas are prime spots for urban development and are generally considered to be safer than the valley floors. As a result, villages and towns have been built on alluvial fans which, during intense storms, may be affected by flooding and/or debris flow processes.

    The study area is located at the foothills of the Maddalena mountains, an elongated NW-SE trending ridge which bounds to the east the wide intermontane basin of Vallo di Diano. The area comprises a wide detrital talus (bajada made up by coalescent alluvial fans, ranging in age from the Middle Pleistocene to the Holocene. Historical analysis was carried out to ascertain the state of activity of the fans and to identify and map the zones most hit by past flooding. According to the information gathered, the Sala Consilina fans would appear prone to debris flows; in the past these processes have produced extensive damage and loss of life in the urban area. The watershed basins feeding the fans have very low response times and may produce debris flow events with high magnitudes. Taking into account the historical damage, the fan surface morphology, and the present urban development (street orientation and hydraulic network, the piedmont area was zoned and various susceptibility classes were detected. These results may represent a useful tool for studies aiming at territorial hazard mapping and civil protection interventions.

  2. Rapid Response to a Typhoon-Induced Flood with an SAR-Derived Map of Inundated Areas: Case Study and Validation

    Directory of Open Access Journals (Sweden)

    Hsiao-Wei Chung

    2015-09-01

    Full Text Available We report the successful case of a rapid response to a flash flood in I-Lan County of Taiwan with a map of inundated areas derived from COSMO-SkyMed 1 radar satellite imagery within 24 hours. The flood was caused by the intensive precipitation brought by Typhoon Soulik in July 2013. Based on the ensemble forecasts of trajectory, an urgent request of spaceborne SAR imagery was made 24 hours before Typhoon Soulik made landfall. Two COSMO-SkyMed images were successfully acquired when the center of Typhoon Soulik had just crossed the northern part of Taiwan. The standard level-1b product (radiometric-corrected, geometric-calibrated and orthorectified image was generated by using the off-the-shelf SARscape software. Following the same approach used with the Expert Landslide and Shadow Area Delineating System, the regional threshold of each tile image was determined to delineate still water surface and quasi-inundated areas in a fully-automatic manner. The results were overlaid on a digital elevation model, and the same tile was visually compared to an optical image taken by Formosat-2 before this event. With this ancillary information, the inundated areas were accurately and quickly identified. The SAR-derived map of inundated areas was published on a web-based platform powered by Google Earth within 24 hours, with the aim of supporting the decision-making process of disaster prevention and mitigation. A detailed validation was made afterwards by comparing the map with in situ data of the water levels at 17 stations. The results demonstrate the feasibility of rapidly responding to a typhoon-induced flood with a spaceborne SAR-derived map of inundated areas. A standard operating procedure was derived from this work and followed by the Water Hazard Mitigation Center of the Water Resources Agency, Taiwan, in subsequent typhoon seasons, such as Typhoon Trami (August, 2013 and Typhoon Soudelor (August, 2015.

  3. Environment-friendly reduction of flood risk and infrastructure damage in a mountain river: Case study of the Czarny Dunajec

    Science.gov (United States)

    Mikuś, Paweł; Wyżga, Bartłomiej; Radecki-Pawlik, Artur; Zawiejska, Joanna; Amirowicz, Antoni; Oglęcki, Paweł

    2016-11-01

    Migration of a mountain river channel may cause erosional risk to infrastructure or settlements on the valley floor. Following a flood of 2010, a cutbank in one of the bends of the main channel of the Czarny Dunajec, Polish Carpathians, approached a local road by 50 m. To arrest the erosion of the laterally migrating channel, water authorities planned construction of a ditch cutting the forested neck of the bend, reinforcement of the ditch banks, and damming the main channel with a boulder groyne. In order to avoid channelization of the highly valued, multithread river reach that would deteriorate its ecological status and cause increased flood risk to downstream reaches, an alternative approach to prevent bank erosion was proposed. The new scheme, applied in 2011, included opening of the inlets to inactive side braids located by the neck of the bend of the main channel. This solution reestablished the flow in the steeper low-flow channels, allowing us to expect a cutoff and abandonment of the main channel during subsequent floods. Gravelly deflectors were constructed directly below the inlets to the reactivated side channels to divert the flow into the channels and prevent the water from entering the main channel. Hydraulic measurements performed before and after the implementation of the scheme confirmed that it enabled shifting the main water current, with the highest average velocity and bed shear stress, from the braid closest to the road to the most distant braid. Similar surveys of fish and benthic macroinvertebrate communities indicated that flow reactivation in the side channels was beneficial for these groups of river biota, increasing their abundance and taxonomic richness in the reach. Not only was the implemented solution significantly less expensive, but it also enhanced ecological functions of the multithread channel and the variability of physical habitat conditions and maintained the role of the reach as a wood debris trap. However, avulsion of the

  4. Application of UAS photogrammetry for assessment of flood driven fluvial dynamics of montane stream. Case study - Roklansky creek, Sumava Mts.

    Science.gov (United States)

    Langhammer, Jakub; Miřijovský, Jakub; Hartvich, Filip; Kaiglová, Jana

    2014-05-01

    Current progress in hydrology and fluvial geomorphology is largely based on new field survey and analysis techniques, employing advanced technologies for monitoring the dynamics of the runoff process, field surveying and for remote monitoring of changes in riverbeds and of fluvial dynamics. Application of these techniques allows researchers to obtain information on a significantly higher qualitative level than using traditional methods of field survey and measurement, either in terms of spatial accuracy and resolution, frequency of sampling or qualitative characteristics of acquired data. The contribution demonstrates the potential of Unmanned Aerial Systems (UAS) for analysis of fluvial dynamics of montane stream, driven by flood in combination with other survey techniques, namely the ground LiDAR scanning, digital granulometry and automated water level monitoring. The UAS photogrammetry is employed in the study to acquire high precision DTMs, enabling reconstruction of riverbed and quantitative analysis of volumetric changes related to initial flood events. The hexacopter UAS platform has been used to acquire the data for photogrammetric analysis of complex stretch of stream with historically elevated fluvial dynamics. The photogrammetric reconstruction enabled to build accurate DTM of riverbed and floodplain before and after the initial event and to calculate the extent of volumetric changes. The potential of UAS photogrammetry for fluvio morphological study is in combination with other monitoring and survey techniques, enabling complex analysis of fluvial dynamics. The magnitude, duration and hydrological properties of initial flood event were derived from automated high frequency water level monitoring. The digital granulometry enabled to analyze the structure of sedimentary material in floodplain. The terrestrial LiDAR scanning allows construction of very detailed 3D models of selected fluvial forms, enabling deeper insight into the effects of fluvial

  5. Integration of rainfall/runoff and geomorphological analyses flood hazard in small catchments: case studies from the southern Apennines (Italy)

    Science.gov (United States)

    Palumbo, Manuela; Ascione, Alessandra; Santangelo, Nicoletta; Santo, Antonio

    2017-04-01

    We present the first results of an analysis of flood hazard in ungauged mountain catchments that are associated with intensely urbanized alluvial fans. Assessment of hydrological hazard has been based on the integration of rainfall/runoff modelling of drainage basins with geomorphological analysis and mapping. Some small and steep, ungauged mountain catchments located in various areas of the southern Apennines, in southern Italy, have been chosen as test sites. In the last centuries, the selected basins have been subject to heavy and intense precipitation events, which have caused flash floods with serious damages in the correlated alluvial fan areas. Available spatial information (regional technical maps, DEMs, land use maps, geological/lithological maps, orthophotos) and an automated GIS-based procedure (ArcGis tools and ArcHydro tools) have been used to extract morphological, hydrological and hydraulic parameters. Such parameters have been used to run the HEC (Hydrologic Engineering Center of the US Army Corps of Engineers) software (GeoHMS, GeoRAS, HMS and RAS) based on rainfall-runoff models, which have allowed the hydrological and hydraulic simulations. As the floods occurred in the studied catchments have been debris flows dominated, the solid load simulation has been also performed. In order to validate the simulations, we have compared results of the modelling with the effects produced by past floods. Such effects have been quantified through estimations of both the sediment volumes within each catchment that have the potential to be mobilised (pre-event) during a sediment transfer event, and the volume of sediments delivered by the debris flows at basins' outlets (post-event). The post-event sediment volume has been quantified through post-event surveys and Lidar data. Evaluation of the pre-event sediment volumes in single catchments has been based on mapping of sediment storages that may constitute source zones of bed load transport and debris flows. For

  6. Leptospirosis in Northeastern Malaysia: Misdiagnosed or Coinfection?

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    AA Noor Rafizah

    2012-07-01

    Full Text Available Background: For the past decade leptospirosis has been re-emerging as an important disease and can be a serious public health issue in a humid tropical and subtropical country such as Malaysia. Leptospirosis also known as “the Great Mimicker” and may be overlooked and under diagnosed due to its varied clinical presentations. Objective: Since leptospirosis is a significant cause of undifferentiated fever and frequently not recognized, this study was conducted to determine the prevalence of this disease among febrile patients in northeastern Malaysia hospitals. Design: A hospital-based cross sectional study was conducted among 999 of febrile patients admitted in 10 hospitals in northeastern Malaysia. Materials and methods: An interviewer-guided proforma sheet on sociodemographic and final hospital diagnosis data was distributed to all adult patients with fever on admission. Serum sample for leptospirosis was screened by IgM Enzyme-linked Immunosorbent Assay test (IgM ELISA and confirmed by Microscopic Agglutination Test (MAT. The cut-off point for positive MAT was ≥1:400 titre in single acute specimen. Results: The seroprevalence of leptospirosis was 8.4% (95% CI: 6.8, 10.3 (n=84 by MAT. In our study, only 31.0% of the confirmed leptospirosis cases by MAT in northeastern Malaysia hospitals were diagnosed as leptospirosis for the final diagnosis on discharge. About 38.1%, 14.3% and 7.1% of the confirmed leptospirosis cases by MAT were diagnosed as dengue fever or dengue hemorrhagic fever, pneumonia and typhoid fever respectively. Conclusion: This study showed that the prevalence of leptospirosis is probably high among febrile patients in northeastern Malaysia hospitals. Awareness and knowledge regarding this disease should be strengthened, especially among public and health care personnel due to the clinical symptoms of leptospirosis mimicking other tropical diseases.

  7. Characterization of floods in the United States

    Science.gov (United States)

    Saharia, Manabendra; Kirstetter, Pierre-Emmanuel; Vergara, Humberto; Gourley, Jonathan J.; Hong, Yang

    2017-05-01

    Floods have gained increasing global significance in the recent past due to their devastating nature and potential for causing significant economic and human losses. Until now, flood characterization studies in the United States have been limited due to the lack of a comprehensive database matching flood characteristics such as peak discharges and flood duration with geospatial and geomorphologic information. The availability of a representative and long archive of flooding events spanning 78 years over a variety of hydroclimatic regions results in a spatially and temporally comprehensive flood characterization over the continental U.S. This study, for the first time, employs a large-event database that is based on actual National Weather Service (NWS) definitions of floods instead of the frequently-adopted case study or frequentist approach, allowing us to base our findings on real definitions of floods. It examines flooding characteristics to identify how space and time scales of floods vary with climatic regimes and geomorphology. Flood events were characterized by linking flood response variables in gauged basins to spatially distributed variables describing climatology, geomorphology, and topography. The primary findings of this study are that the magnitude of flooding is highest is regions such as West Coast and southeastern U.S. which experience the most extraordinary precipitation. The seasonality of flooding varies greatly from maxima during the cool season on the West Coast, warm season in the desert Southwest, and early spring in the Southeast. The fastest responding events tend to be in steep basins of the arid Southwest caused by intense monsoon thunderstorms and steep terrain. The envelope curves of unit peak discharge are consistent with those reported for Europe and worldwide. But significant seasonal variability was observed in floods of the U.S. compared to Europe that is attributed to the diversity of causative rainfall ranging from synoptic

  8. The use of cartographic modeling to assess the impacts of coastal flooding: a case study of Port Said Governorate, Egypt.

    Science.gov (United States)

    Abou Samra, Rasha M

    2017-09-01

    Low-set coastal areas are expected to aggravate inundation on account of sea level rise (SLR). The present study is planned to appraise the impacts of coastal flooding in Port Said city, Egypt by using remote sensing, GIS, and cartographic modeling techniques. To accomplish this scope, Landsat 8-OLI image dated 2016 and SRTM 1Arc-Second Digital Elevation Model (DEM) data were used. Landsat image was classified into seven land use and land cover (LULC) classes by using remote sensing and GIS's software. Different inundation scenarios 1.0, 2.0, and 3.0-m coastal elevation were used to figure the influence of SLR on the study area. Estimation of potential losses under SLR was made by overlaying the expected scenarios on land use. The inundation areas under the expected SLR scenarios of 1.0, 2.0, and 3.0 m were estimated at 827.49, 1072.67, and 1179.41 km(2), respectively. In conclusion, this study demonstrated that expected coastal flooding scenarios will lead up to serious impacts on LULC classes and coastal features in the study area.

  9. Deep Tunnel for Regulating Combined Sewer Overflow Pollution and Flood Disaster: A Case Study in Guangzhou City, China

    Directory of Open Access Journals (Sweden)

    Haichun Wu

    2016-08-01

    Full Text Available The DongHaoChong (DHC basin is located in the central city zone of Guangzhou City, China. Owing to the high density of buildings and low quality of the drainage pipe network in the city, diversion of rain and sewage is difficult. Waterlogging occurs frequently and combined sewer overflow (CSO pollution is a serious problem during the rainy season. Therefore, a deep tunnel for the DongHaoChong basin has been planned and its construction is currently underway. An urban rainstorm model for the DongHaoChong basin was developed on the basis of the Storm Water Management Model (SWMM, and both the interception effect of CSO pollution and the degree of mitigation of flood were analyzed. Reasonable scenarios for the deep tunnel in terms of rainstorms with different design recurrence periods were evaluated. From the viewpoints of preventing rainstorm waterlogging disasters and protecting water quality in the region downstream of DongHaoChong River, the river flood control and drainage capacities of the region were improved to a 2-year rainstorm design recurrence period by the construction of the deep tunnel. Furthermore, the main pollutant load of the CSO is expected to be reduced by about 30%–40%.

  10. GIS ANALYSIS OF POPULATION EVACUATION FROM FLASH FLOODSCASE STUDY, ȚÂȘLA DRAINAGE BASIN, ROMANIA

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    A. SIMA

    2016-03-01

    Full Text Available Țâșla watershed, composing sub-basin of the larger Vișeu basin, is a highly anthropic area, with an extremely packed residential and transportation infrastructure, mainly along the Țâșla watercourse. Mining and tourist activities have always been and still are the outcome of a great natural potential, this fact leading to the area always getting ranked as one of the top economic centers in Maramureș County. The high frequency of flash flooding is jeopardizing the socio-economic progress of the area, causing substantial damage. This paper’s goal is the adaptation of a GIS tool, proposed by researchers from the U.S. Geological Survey – USGS (Jeanne M. Jones, Peter Ng, Nathan J. Wood, 2014, used in the flash flooding population evacuation analysis, etc. This method is based upon the digital elevation model, land cover, hazard zones and safe zones analysis. The results (evacuation time, evacuation corridors, etc can be a relevant contribution to the decision making management of the emergency situations.

  11. Terse messaging and public health in the midst of natural disasters: the case of the Boulder floods.

    Science.gov (United States)

    Sutton, Jeannette; League, Cedar; Sellnow, Timothy L; Sellnow, Deanna D

    2015-01-01

    Social media are quickly becoming the channel of choice for disseminating emergency warning messages. However, relatively little data-driven research exists to inform effective message design when using these media. The present study addresses that void by examining terse health-related warning messages sent by public safety agencies over Twitter during the 2013 Boulder, CO, floods. An examination of 5,100 tweets from 52 Twitter accounts over the course of the 5-day flood period yielded several key conclusions and implications. First, public health messages posted by local emergency management leaders are most frequently retweeted by organizations in our study. Second, emergency public health messages focus primarily on drinking water in this event. Third, terse messages can be designed in ways that include imperative/instructional and declarative/explanatory styles of content, both of which are essential for promoting public health during crises. These findings demonstrate that even terse messages delivered via Twitter ought to provide information about the hazard event, its impact, and actionable instructions for self-protection.

  12. Optimization of wetland restoration siting and zoning in flood retention areas of river basins in China: A case study in Mengwa, Huaihe River Basin

    Science.gov (United States)

    Zhang, Xiaolei; Song, Yuqin

    2014-11-01

    Wetland restoration in floodplains is an ecological solution that can address basin-wide flooding issues and minimize flooding and damages to riverine and downstream areas. High population densities, large economic outputs, and heavy reliance on water resources make flood retention and management pressing issues in China. To balance flood control and sustainable development economically, socially, and politically, flood retention areas have been established to increase watershed flood storage capacities and enhance the public welfare for the populace living in the areas. However, conflicts between flood storage functions and human habitation appear irreconcilable. We developed a site-specific methodology for identifying potential sites and functional zones for wetland restoration in a flood retention area in middle and eastern China, optimizing the spatial distribution and functional zones to maximize flood control and human and regional development. This methodology was applied to Mengwa, one of 21 flood retention areas in China's Huaihe River Basin, using nine scenarios that reflected different flood, climatic, and hydraulic conditions. The results demonstrated improved flood retention and ecological functions, as well as increased economic benefits.

  13. Development processes of a master plan for flood protection and mitigation in a community area: A case study of Roi Et province

    Directory of Open Access Journals (Sweden)

    Chatchai Jothityangkoon

    2015-12-01

    Full Text Available Development processes of a master plan formulation for flood protection and mitigation consists of the selection process of a targeted area based on risk level, developing a present and future flood inundation map and a flood risk map and identify direction and drainage capacity of the targeted area. Main causes of flooding in the area can be identified leading to designing flood protection and a flood drainage system in both structural and non-structural measures, prior to a public hearing process from stakeholders to finalize the master plan to provide maximum benefits and less negative impact. These processes are applied to Roi Et Province. Based on flood risk criteria, 24 municipalities with high risk are selected. The cause of flooding in the municipality area can be combined in 2 groups, flooding from low efficiency of storm drainage capacity and flooding from overbank flow from the Mun, Chi and Yang Rivers. Structural measures for the first and second group are the improvement of the existing system or changing a new drainage system and the improvement of existing river dikes and levees. It is also possible to design and construct a new one. Constructing a polder system for the community area, requires a budget about 3,338 million baht. To support structural measures, non-structural measures are required, for example, a flood warning system, an emergency response plan during flood disaster.

  14. Potential flood hazard assessment by integration of ALOS PALSAR and ASTER GDEM: a case study for the Hoa Chau commune, Hoa Vang district, in central Vietnam

    Science.gov (United States)

    Huong, Do Thi Viet; Nagasawa, Ryota

    2014-01-01

    The potential flood hazard was assessed for the Hoa Chau commune in central Vietnam in order to identify the high flood hazard zones for the decision makers who will execute future rural planning. A new approach for deriving the potential flood hazard based on integration of inundation and flow direction maps is described. Areas inundated in the historical flood event of 2007 were extracted from Advanced Land Observing Satellite (ALOS) phased array L-band synthetic aperture data radar (PALSAR) images, while flow direction characteristics were derived from the ASTER GDEM to extract the depressed surfaces. Past flood experience and the flow direction were then integrated to analyze and rank the potential flood hazard zones. The land use/cover map extracted from LANDSAT TM and flood depth point records from field surveys were utilized to check the possibility of susceptible inundated areas, extracting data from ALOS PALSAR and ranking the potential flood hazard. The estimation of potential flood hazard areas revealed that 17.43% and 17.36% of Hoa Chau had high and medium potential flood hazards, respectively. The flow direction and ALOS PALSAR data were effectively integrated for determining the potential flood hazard when hydrological and meteorological data were inadequate and remote sensing images taken during flood times were not available or were insufficient.

  15. Sustainable Improvement of Urban River Network Water Quality and Flood Control Capacity by a Hydrodynamic Control Approach-Case Study of Changshu City

    Science.gov (United States)

    Xie, Chen; Yang, Fan; Liu, Guoqing; Liu, Yang; Wang, Long; Fan, Ziwu

    2017-01-01

    Water environment of urban rivers suffers degradation with the impacts of urban expansion, especially in Yangtze River Delta. The water area in cites decreased sharply, and some rivers were cut off because of estate development, which brings the problems of urban flooding, flow stagnation and water deterioration. The approach aims to enhance flood control capability and improve the urban river water quality by planning gate-pump stations surrounding the cities and optimizing the locations and functions of the pumps, sluice gates, weirs in the urban river network. These gate-pump stations together with the sluice gates and weirs guarantee the ability to control the water level in the rivers and creating hydraulic gradient artificially according to mathematical model. Therefore the flow velocity increases, which increases the rate of water exchange, the DO concentration and water body self-purification ability. By site survey and prototype measurement, the river problems are evaluated and basic data are collected. The hydrodynamic model of the river network is established and calibrated to simulate the scenarios. The schemes of water quality improvement, including optimizing layout of the water distribution projects, improvement of the flow discharge in the river network and planning the drainage capacity are decided by comprehensive Analysis. Finally the paper introduces the case study of the approach in Changshu City, where the approach is successfully implemented.

  16. Flash Flood Hazard Mapping Using Satellite Images and GIS Tools: A case study of Najran City, Kingdom of Saudi Arabia (KSA)

    OpenAIRE

    Ismail Elkhrachy

    2015-01-01

    Flash flood in the cities led to high levels of water in the streets and roads, causing many problems such as bridge collapse, building damage and traffic problems. It is impossible to avoid risks of floods or prevent their occurrence, however it is plausible to work on the reduction of their effects and to reduce the losses which they may cause. Flash flood mapping to identify sites in high risk flood zones is one of the powerful tools for this purpose. Mapping flash flood will be beneficial...

  17. Flash Flood Hazard Mapping Using Satellite Images and GIS Tools: A case study of Najran City, Kingdom of Saudi Arabia (KSA

    Directory of Open Access Journals (Sweden)

    Ismail Elkhrachy

    2015-12-01

    Full Text Available Flash flood in the cities led to high levels of water in the streets and roads, causing many problems such as bridge collapse, building damage and traffic problems. It is impossible to avoid risks of floods or prevent their occurrence, however it is plausible to work on the reduction of their effects and to reduce the losses which they may cause. Flash flood mapping to identify sites in high risk flood zones is one of the powerful tools for this purpose. Mapping flash flood will be beneficial to urban and infrastructure planners, risk managers and disaster response or emergency services during extreme and intense rainfall events. The objective of this paper is to generate flash flood map for Najran city, Saudi Arabia, using satellite images and GIS tools. To do so, we use SPOT and SRTM DEMs data for which accuracy assessment is achieved by using check points, obtained by GPS observations. Analytical Hierarchical Process (AHP is used to determine relative impact weight of flood causative factors to get a composite flood hazard index (FHI. The causative factors in this study are runoff, soil type, surface slope, surface roughness, drainage density, distance to main channel and land use. All used data are finally integrated in an ArcMap to prepare a final flood hazard map for study area. The areas in high risk flood zones are obtained by overlaying the flood hazard index map with the zone boundaries layer. The affected population number and land area are determined and compared.

  18. Simulation of the hydrogeologic effects of oil-shale mining on the neighbouring wetland water balance: case study in north-eastern Estonia

    Science.gov (United States)

    Marandi, Andres; Karro, Enn; Polikarpus, Maile; Jõeleht, Argo; Kohv, Marko; Hang, Tiit; Hiiemaa, Helen

    2013-11-01

    The water balance of wetlands plays an integral role in their function. Developments adjacent to wetlands can affect their water balance through impacts on groundwater flow and increased discharge in the area, and they can cause lowering of the wetland water table. A 430 km2 area was selected for groundwater modelling to asses the effect of underground mining on the water balance of wetlands in north-eastern Estonia. A nature conservation area (encompassing Selisoo bog) is within 3 km of an underground oil-shale mine. Two future mining scenarios with different areal extents of mining were modeled and compared to the present situation. Results show that the vertical hydraulic conductivity of the subsurface is of critical importance to potential wetland dewatering as a result of mining. Significant impact on the Selisoo bog water balance will be caused by the approaching mine but there will be only minor additional impacts from mining directly below the bog. The major impact will arise before that stage, when the underground mine extension reaches the border of the nature conservation area; since the restriction of activities in this area relates to the ground surface, the conservation area’s border is not sufficiently protective in relation to underground development.

  19. Analysis of river pollution data from low-flow period by means of multivariate techniques: a case study from the oil-shale industry region, northeastern Estonia.

    Science.gov (United States)

    Truu, Jaak; Heinaru, Eeva; Talpsep, Ene; Heinaru, Ain

    2002-01-01

    The oil-shale industry has created serious pollution problems in northeastern Estonia. Untreated, phenol-rich leachate from semi-coke mounds formed as a by-product of oil-shale processing is discharged into the Baltic Sea via channels and rivers. An exploratory analysis of water chemical and microbiological data sets from the low-flow period was carried out using different multivariate analysis techniques. Principal component analysis allowed us to distinguish different locations in the river system. The riverine microbial community response to water chemical parameters was assessed by co-inertia analysis. Water pH, COD and total nitrogen were negatively related to the number of biodegradative bacteria, while oxygen concentration promoted the abundance of these bacteria. The results demonstrate the utility of multivariate statistical techniques as tools for estimating the magnitude and extent of pollution based on river water chemical and microbiological parameters. An evaluation of river chemical and microbiological data suggests that the ambient natural attenuation mechanisms only partly eliminate pollutants from river water, and that a sufficient reduction of more recalcitrant compounds could be achieved through the reduction of wastewater discharge from the oil-shale chemical industry into the rivers.

  20. The north-eastern aeolian 'European Sand Belt' as potential record of environmental changes: A case study from Eastern Latvia and Southern Estonia

    Science.gov (United States)

    Kalińska-Nartiša, Edyta; Thiel, Christine; Nartišs, Māris; Buylaert, Jan-Pieter; Murray, Andrew S.

    2016-09-01

    The Latvian and Estonian inland dunes belong to the north-eastern part of the 'European Sand Belt' (ESB). These dunes are widely distributed over broad glaciolacustrine plains and Late Glacial alluvial deltas, considered to be potential sources for the aeolian material. Little is known about these aeolian sediments and their substratum; here we present a detailed sedimentary structural and textural characterisation together with a luminescence-based chronology. Through a comparison between grain-size, rounding of quartz grains and surface characteristics in medium/coarse (0.5-0.8 mm) sand, and the light mineral content, we found an alternation of aeolian and periglacial components. Further, short-lasting aeolian abrasion and/or transportation periods, and a significant contribution of a nearby sediment source are suggested. Luminescence dating points to aeolian sand accumulation and dune formation between ∼16 ka and ∼9 ka. However, we also observed some presumably watertable controlled environmental conditions at ∼13 ka; this corresponds with the occurrence of an ice-dammed/proglacial lake.

  1. The inversion of average vegetation height using ICESat GLAS and MODIS data: a case study of three provinces in Northeastern China

    Science.gov (United States)

    Cheng, Feng; Wang, Cheng; Jiang, Xiaoguang

    2010-09-01

    The average vegetation height can be accurately extracted from ICESat GLAS data, however, a certain spatial interval exist in laser strips and dots reduces the mapping accuracy of average canopy height after the interpolation of the GLAS data. The MODIS-BRDF/albedo data consist of canopy structural data, such as LAI, canopy height etc. So the combination of ICESat GLAS and MODIS data can be obtained more accurate distribution of average canopy height and achieve the distribution of continuous canopy height. In this paper, the GLAS / MODIS data were collected in forest-rich three provinces in northeastern China. We firstly filtered GLAS waveform data and get the average vegetation height, and then selected the optional MODIS-BRDF / albedo bands to retrieve the average vegetation height. An artificial neural networks model was esTablelished by training the MODIS BRDF data, and finally obtained the average vegetation height over the whole three provinces. The fusion method between GLAS data and optical remote sensing image was proposed to make up for their shortages and obtained a continuous distribution of average vegetation height. It increases the analysis dimensions of forest ecosystem and produces more accurate data for forest biomass and carbon storage estimates.

  2. Long-term remote sensing monitoring coal mining activity in resource-based cities: a case study of Qitaihe City, Northeastern China

    Science.gov (United States)

    Liu, L.; Zhou, J. S.

    2017-01-01

    Mining activity has strongly impacted the sustainable socioeconomic development of resource-based cities. The systematic monitoring of the change in mining activity can provide evidence for the transition and future development of resource-based cities. This paper chose Qitaihe, one of the four coal mining cities in northeastern China as the study area. Remote sensing and Geographical Information Systems (GIS) technique, as well as methods on landscape pattern analysis were used to study the evolution of mining activity from 4 different periods over 58 years’ time. Results showed that the area of land used in mining increased by about six times during the study period with cultivated land the main type that contributed to this increase. Mining activity showed an eastward trend, developing from one concentration circle to four circles, from a disordered system to a relatively integrated system. It was also suggested that differentiated policies should be adopted in different mining circles. This study also provides a framework for future city planning and sustainable development.

  3. FLOOD RISK FACTORS IN SUBURBAN AREA IN THE CONTEXT OF CLIMATE CHANGE ADAPTATION POLICIES – CASE STUDY OF WROCLAW, POLAND

    Directory of Open Access Journals (Sweden)

    Szymon Szewrański

    2015-02-01

    Full Text Available The uncontrolled sprawl of urban development exerts environmental impact in rural areas. The aim of this study is to identify areas vulnerable to climate change in the context of implementation of policies adapting to climate change at the local level. Such areas can be defined as those where the negative implication of flesh flood overlapping with soil sealing is observed. The study areas composed of municipalities which are influenced by the urban sprawl process of the city of Wroclaw, Poland. The analyses were performed using publicly available spatial data from aerial orthophotomaps from 2004–2012, the satellite images; archival and current land use maps. The database CORINE 1990, 2000, 2006; Urban Atlas and geodatabase of the European Environment Agency were also of an important usage for this study.

  4. Assessing the impact of hydrodynamics on large-scale flood wave propagation - a case study for the Amazon Basin

    Science.gov (United States)

    Hoch, Jannis M.; Haag, Arjen V.; van Dam, Arthur; Winsemius, Hessel C.; van Beek, Ludovicus P. H.; Bierkens, Marc F. P.

    2017-01-01

    Large-scale flood events often show spatial correlation in neighbouring basins, and thus can affect adjacent basins simultaneously, as well as result in superposition of different flood peaks. Such flood events therefore need to be addressed with large-scale modelling approaches to capture these processes. Many approaches currently in place are based on either a hydrologic or a hydrodynamic model. However, the resulting lack of interaction between hydrology and hydrodynamics, for instance, by implementing groundwater infiltration on inundated floodplains, can hamper modelled inundation and discharge results where such interactions are important. In this study, the global hydrologic model PCR-GLOBWB at 30 arcmin spatial resolution was one-directionally and spatially coupled with the hydrodynamic model Delft 3D Flexible Mesh (FM) for the Amazon River basin at a grid-by-grid basis and at a daily time step. The use of a flexible unstructured mesh allows for fine-scale representation of channels and floodplains, while preserving a coarser spatial resolution for less flood-prone areas, thus not unnecessarily increasing computational costs. In addition, we assessed the difference between a 1-D channel/2-D floodplain and a 2-D schematization in Delft 3D FM. Validating modelled discharge results shows that coupling PCR-GLOBWB to a hydrodynamic routing scheme generally increases model performance compared to using a hydrodynamic or hydrologic model only for all validation parameters applied. Closer examination shows that the 1-D/2-D schematization outperforms 2-D for r2 and root mean square error (RMSE) whilst having a lower Kling-Gupta efficiency (KGE). We also found that spatial coupling has the significant advantage of a better representation of inundation at smaller streams throughout the model domain. A validation of simulated inundation extent revealed that only those set-ups incorporating 1-D channels are capable of representing inundations for reaches below the

  5. Use of historical information in extreme surge frequency estimation: case of the marine flooding on the La Rochelle site in France

    Directory of Open Access Journals (Sweden)

    Y. Hamdi

    2014-09-01

    Full Text Available Nuclear power plants located in the French Atlantic coast are designed to be protected against extreme environmental conditions. The French authorities remain cautious by adopting a strict policy of nuclear plants flood prevention. Although coastal nuclear facilities in France are designed to very low probabilities of failure (e.g. 1000 year surge, exceptional surges (outliers induced by exceptional climatic events had shown that the extreme sea levels estimated with the current statistical approaches could be underestimated. The estimation of extreme surges then requires the use of a statistical analysis approach having a more solid theoretical motivation. This paper deals with extreme surge frequency estimation using historical information (HI about events occurred before the systematic record period. It also contributes to addressing the problem of the presence of outliers in data sets. The frequency models presented in the present paper have been quite successful in the field of hydrometeorology and river flooding but they have not been applied to sea levels data sets to prevent marine flooding. In this work, we suggest two methods of incorporating the HI: the Peaks-Over-Threshold method with HI (POTH and the Block Maxima method with HI (BMH. Two kinds of historical data can be used in the POTH method: classical Historical Maxima (HMax data, and Over a Threshold Supplementary (OTS data. In both cases, the data are structured in historical periods and can be used only as complement to the main systematic data. On the other hand, in the BMH method, the basic hypothesis in statistical modeling of HI is that at least one threshold of perception exists for the whole period (historical and systematic and that during a giving historical period preceding the period of tide gauging, only information about surges above this threshold have been recorded or archived. The two frequency models were applied to a case study from France, at the La Rochelle

  6. Use of historical information in extreme-surge frequency estimation: the case of marine flooding on the La Rochelle site in France

    Science.gov (United States)

    Hamdi, Y.; Bardet, L.; Duluc, C.-M.; Rebour, V.

    2015-07-01

    Nuclear power plants located in the French Atlantic coast are designed to be protected against extreme environmental conditions. The French authorities remain cautious by adopting a strict policy of nuclear-plants flood prevention. Although coastal nuclear facilities in France are designed to very low probabilities of failure (e.g., 1000-year surge), exceptional surges (outliers induced by exceptional climatic events) have shown that the extreme sea levels estimated with the current statistical approaches could be underestimated. The estimation of extreme surges then requires the use of a statistical analysis approach having a more solid theoretical motivation. This paper deals with extreme-surge frequency estimation using historical information (HI) about events occurred before the systematic record period. It also contributes to addressing the problem of the presence of outliers in data sets. The frequency models presented in the present paper have been quite successful in the field of hydrometeorology and river flooding but they have not been applied to sea level data sets to prevent marine flooding. In this work, we suggest two methods of incorporating the HI: the peaks-over-threshold method with HI (POTH) and the block maxima method with HI (BMH). Two kinds of historical data can be used in the POTH method: classical historical maxima (HMax) data, and over-a-threshold supplementary (OTS) data. In both cases, the data are structured in historical periods and can be used only as complement to the main systematic data. On the other hand, in the BMH method, the basic hypothesis in statistical modeling of HI is that at least one threshold of perception exists for the whole period (historical and systematic) and that during a giving historical period preceding the period of tide gauging, only information about surges above this threshold have been recorded or archived. The two frequency models were applied to a case study from France, at the La Rochelle site where

  7. Use of historical information in extreme surge frequency estimation: case of the marine flooding on the La Rochelle site in France

    Science.gov (United States)

    Hamdi, Y.; Bardet, L.; Duluc, C.-M.; Rebour, V.

    2014-09-01

    Nuclear power plants located in the French Atlantic coast are designed to be protected against extreme environmental conditions. The French authorities remain cautious by adopting a strict policy of nuclear plants flood prevention. Although coastal nuclear facilities in France are designed to very low probabilities of failure (e.g. 1000 year surge), exceptional surges (outliers induced by exceptional climatic events) had shown that the extreme sea levels estimated with the current statistical approaches could be underestimated. The estimation of extreme surges then requires the use of a statistical analysis approach having a more solid theoretical motivation. This paper deals with extreme surge frequency estimation using historical information (HI) about events occurred before the systematic record period. It also contributes to addressing the problem of the presence of outliers in data sets. The frequency models presented in the present paper have been quite successful in the field of hydrometeorology and river flooding but they have not been applied to sea levels data sets to prevent marine flooding. In this work, we suggest two methods of incorporating the HI: the Peaks-Over-Threshold method with HI (POTH) and the Block Maxima method with HI (BMH). Two kinds of historical data can be used in the POTH method: classical Historical Maxima (HMax) data, and Over a Threshold Supplementary (OTS) data. In both cases, the data are structured in historical periods and can be used only as complement to the main systematic data. On the other hand, in the BMH method, the basic hypothesis in statistical modeling of HI is that at least one threshold of perception exists for the whole period (historical and systematic) and that during a giving historical period preceding the period of tide gauging, only information about surges above this threshold have been recorded or archived. The two frequency models were applied to a case study from France, at the La Rochelle site where

  8. Urban flood risk assessment using sewer flooding databases.

    Science.gov (United States)

    Caradot, Nicolas; Granger, Damien; Chapgier, Jean; Cherqui, Frédéric; Chocat, Bernard

    2011-01-01

    Sustainable water management is a global challenge for the 21st century. One key aspect remains protection against urban flooding. The main objective is to ensure or maintain an adequate level of service for all inhabitants. However, level of service is still difficult to assess and the high-risk locations difficult to identify. In this article, we propose a methodology, which (i) allows water managers to measure the service provided by the urban drainage system with regard to protection against urban flooding; and (ii) helps stakeholders to determine effective strategies for improving the service provided. One key aspect of this work is to use a database of sewer flood event records to assess flood risk. Our methodology helps urban water managers to assess the risk of sewer flooding; this approach does not seek to predict flooding but rather to inform decision makers on the current level of risk and on actions which need to be taken to reduce the risk. This work is based on a comprehensive definition of risk, including territorial vulnerability and perceptions of urban water stakeholders. This paper presents the results and the methodological contributions from implementing the methodology on two case studies: the cities of Lyon and Mulhouse.

  9. Considering historical flood events in flood frequency analysis: Is it worth the effort?

    Science.gov (United States)

    Schendel, Thomas; Thongwichian, Rossukon

    2017-07-01

    Information about historical floods can be useful in reducing uncertainties in flood frequency estimation. Since the start of the historical record is often defined by the first known flood, the length of the true historical period M remains unknown. We have expanded a previously published method of estimating M to the case of several known floods within the historical period. We performed a systematic evaluation of the usefulness of including historical flood events into flood frequency analysis for a wide range of return periods and studied bias as well as relative root mean square error (RRMSE). Since we used the generalized extreme value distribution (GEV) as parent distribution, we were able to investigate the impact of varying the skewness on RRMSE. We confirmed the usefulness of historical flood data regarding the reduction of RRMSE, however we found that this reduction is less pronounced the more positively skewed the parent distribution was. Including historical flood information had an ambiguous effect on bias: depending on length and number of known floods of the historical period, bias was reduced for large return periods, but increased for smaller ones. Finally, we customized the test inversion bootstrap for estimating confidence intervals to the case that historical flood events are taken into account into flood frequency analysis.

  10. Evaluating the impact and risk of pluvial flash flood on intra-urban road network: A case study in the city center of Shanghai, China

    Science.gov (United States)

    Yin, Jie; Yu, Dapeng; Yin, Zhane; Liu, Min; He, Qing

    2016-06-01

    Urban pluvial flood are attracting growing public concern due to rising intense precipitation and increasing consequences. Accurate risk assessment is critical to an efficient urban pluvial flood management, particularly in transportation sector. This paper describes an integrated methodology, which initially makes use of high resolution 2D inundation modeling and flood depth-dependent measure to evaluate the potential impact and risk of pluvial flash flood on road network in the city center of Shanghai, China. Intensity-Duration-Frequency relationships of Shanghai rainstorm and Chicago Design Storm are combined to generate ensemble rainfall scenarios. A hydrodynamic model (FloodMap-HydroInundation2D) is used to simulate overland flow and flood inundation for each scenario. Furthermore, road impact and risk assessment are respectively conducted by a new proposed algorithm and proxy. Results suggest that the flood response is a function of spatio-temporal distribution of precipitation and local characteristics (i.e. drainage and topography), and pluvial flash flood is found to lead to proportionate but nonlinear impact on intra-urban road inundation risk. The approach tested here would provide more detailed flood information for smart management of urban street network and may be applied to other big cities where road flood risk is evolving in the context of climate change and urbanization.

  11. Joint impact of rainfall and tidal level on flood risk in a coastal city with a complex river network: a case study of Fuzhou City, China

    Directory of Open Access Journals (Sweden)

    J. J. Lian

    2013-02-01

    Full Text Available Coastal cities are particularly vulnerable to flood under multivariable conditions, such as heavy precipitation, high sea levels, and storms. The combined effect of multiple sources and the joint probability of extremes should be considered to assess and manage flood risk better. This paper aims to study the combined effect of rainfall and the tidal level of the receiving water body on flood probability and severity in Fuzhou City, which has a complex river network. Flood severity under a range of precipitation intensities, with return periods (RPs of 5 yr to 100 yr, and tidal levels was assessed through a hydrodynamic model verified by data observed during Typhoon Longwang in 2005. According to the percentages of the river network where flooding occurred, the threshold conditions for flood severity were estimated in two scenarios: with and without working pumps. In Fuzhou City, working pumps efficiently reduce flood risk from precipitation within a 20-yr RP. However, the pumps may not work efficiently when rainfall exceeds a 100-yr RP because of the limited conveyance capacity of the river network. Joint risk probability was estimated through the optimal copula. The joint probability of rainfall and tidal level both exceeding their threshold values is very low, and the greatest threat in Fuzhou comes from heavy rainfall. However, the tidal level poses an extra risk of flood. Given that this extra risk is ignored in the design of flood defense in Fuzhou, flood frequency and severity may be higher than understood during design.

  12. Late Permian basalts in the Yanghe area, eastern Sichuan Province, SW China: Implications for the geodynamics of the Emeishan flood basalt province and Permian global mass extinction

    Science.gov (United States)

    Li, Hongbo; Zhang, Zhaochong; Santosh, M.; Lü, Linsu; Han, Liu; Liu, Wei

    2017-02-01

    We report the finding of a ∼20 m thick sequence of massive pyroxene-plagioclase-phyric basalt lava flows in the Yanghe area of the northeastern Sichuan Basin, within the Yangtze craton of SW China, which were previously considered to be located outside the Emeishan flood basalt province. This basaltic sequence above the middle Permian Maokou Formation (Fm.) is overlain by the late Permian Longtan Fm. Thus, the Yanghe basalts should be stratigraphically correlated with the Emeishan flood basalts. The Yanghe basalts show typical oceanic island basalt (OIB) affinity, and geochemically resemble Emeishan basalts, especially in the case of high-Ti (HT) basalts from the eastern domain of the Emeishan flood basalt province. The rocks have low age-corrected (87Sr/86Sr)t (t = 260 Ma) ratios (0.704158-0.704929) and Pb isotopic ratios [206Pb/204Pb(t) (18.264-18.524), 207Pb/204Pb(t) (15.543-15.58), and 208Pb/204Pb(t) (38.147-38.519)], and positive εNd(t) values (+3.15 to +3.61), suggesting that the lavas have not undergone any significant crustal contamination. The crystallization temperature of clinopyroxene is estimated to be 1368-1420 °C, suggesting anomalously thermal inputs from a mantle source and a possible plume-head origin. The fractionation of middle rare earth elements (MREE) to heavy REE (HREE) suggests that these rocks were produced by small degrees of partial melting of mantle peridotite within the garnet-spinel transition region. The stratigraphic relationships and similar geochemical signatures with the Emeishan flood basalts suggest that the Yanghe basalts are part of the Emeishan flood basalt province and can be considered as the northeastern limit of the Emeishan flood basalt province. Our finding extends the diameter of the Emeishan flood basalt province to ∼1200-1400 km, covering an area of up to ∼7 × 105 km2, two times more than previously estimated. The larger areal extent and giant eruption volume, incorporating the Sichuan Basin, lend support

  13. 厄尔尼诺与广西致洪暴雨的关系%Research on the Relationship Between ENSO Cases and Flash-Flood-Producing Rainstorm in Guangxi

    Institute of Scientific and Technical Information of China (English)

    林开平; 李耀先; 李秀存; 梁隽玫

    2001-01-01

    Based on analyzing the relationship between ENSO cases and the flash-flood-producing rainstorm in Guangxi, the result show that the two of them are close. Most of the flash-flood-producing rainstorms happened during the period of ENSO appearing, or in next year after ENSO cases ended. It was very similar that the variability of occurring frequency during the inter-decade, between ENSO cases and the flash-flood-producing rainstorm in Guangxi. In additional, the causes of the flash-flood-producing rainstorm stimulated by ENSO cases in Guangxi was discussed, as well.%分析了ENSO事件的出现与广西致洪暴雨的关系,结果表明了两者关系密切,广西的致洪暴雨基本上都出现于ENSO事件年或ENSO事件结束后的一年里;ENSO事件的出现频率随年代的变化与广西致洪暴雨出现频率随年代的变化非常吻合。此外,还就厄尔尼诺对广西致洪暴雨形成的可能机制进行探讨。

  14. The spatial multiscale variability of heavy metals based on factorial kriging analysis:A case study in the northeastern Beibu Gulf

    Institute of Scientific and Technical Information of China (English)

    ZHAO Jianru; CHU Fengyou; JIN Xianglong; WU Qingsong; YANG Kehong; GE Qian; JIN Lu

    2015-01-01

    Factorial kriging analysis is applied to the research on the spatial multiscale variability of heavy metals in submarine. It is used to analyze the multiscale spatial structures of seven heavy metals, Ni, Cu, Zn, Pb, Cr, As and Cd in the surface sediment from the northeastern of Beibu Gulf, identify and separate spatial variations at different scales of heavy metals, and discuss the provenance of heavy metals and the influencing factors. The results show that the existence of three-scale spatial variations those consist of nugget effect, a spherical structure with range of 30 km (short-range scale) and a spherical structure with range of 140 km (long-range scale) in the linear model of coregionalization fitted. The spatial distribution features of seven heavy metals at short-range scale reflect “spot-like” or “stripe-like” local-scale spatial variations; the spatial distribution features of the seven heavy metals at long-range scale represent “slice-like” regional-scale spatial variations. At local scale, Zn, Cr, Ni, Cu, Pb and Cd are derived primarily from parent materials of Hainan Island, Leizhou Peninsula and Guangxi land, whose spatial distribution characteristics are controlled by granularity of sediments, while As is influenced dominantly by human pollution components from Hainan Island and Leizhou Peninsula. At regional scale, Zn, Cr, Ni and Cu originate primarily from parent rock materials of Leizhou Peninsula and Hainan Island, secondly from Guangxi land; As originated primarily from parent rock materials from Hainan Island, secondly from Leizhou Peninsula and Guangxi land. These metals are transported and migrated with sediments dominated by the anticlockwise circulation of Beibu Gulf year-round, deposited in “convergence center”, forming the whole sedimentary pattern in direction of NWW-NNW at regional scale. The difference in distribution type between As and other metals at regional scale is mainly due to their different geochemical

  15. Can We Use Tree Rings of Black Alder to Reconstruct Lake Levels? A Case Study for the Mecklenburg Lake District, Northeastern Germany.

    Directory of Open Access Journals (Sweden)

    Ernst van der Maaten

    Full Text Available In this study, we explore the potential to reconstruct lake-level (and groundwater fluctuations from tree-ring chronologies of black alder (Alnus glutinosa L. for three study lakes in the Mecklenburg Lake District, northeastern Germany. As gauging records for lakes in this region are generally short, long-term reconstructions of lake-level fluctuations could provide valuable information on past hydrological conditions, which, in turn, are useful to assess dynamics of climate and landscape evolution. We selected black alder as our study species as alder typically thrives as riparian vegetation along lakeshores. For the study lakes, we tested whether a regional signal in lake-level fluctuations and in the growth of alder exists that could be used for long-term regional hydrological reconstructions, but found that local (i.e. site-specific signals in lake level and tree-ring chronologies prevailed. Hence, we built lake/groundwater-level reconstruction models for the three study lakes individually. Two sets of models were considered based on (1 local tree-ring series of black alder, and (2 site-specific Standardized Precipitation Evapotranspiration Indices (SPEI. Although the SPEI-based models performed statistically well, we critically reflect on the reliability of these reconstructions, as SPEI cannot account for human influence. Tree-ring based reconstruction models, on the other hand, performed poor. Combined, our results suggest that, for our study area, long-term regional reconstructions of lake-level fluctuations that consider both recent and ancient (e.g., archaeological wood of black alder seem extremely challenging, if not impossible.

  16. Social creation of Risk: Flood and Land Subsidence in Guadalajara Metropolitan Zone, México (case study)

    Science.gov (United States)

    Zarate-Del Valle, P. F.; Vargas Del Río, D.

    2010-12-01

    Sanitary sewer of Guadalajara Metropolitan Zone (GMZ) is a project designed in early 1960s for discharges of one million inhabitants, precipitation forecast based in return periods of 25 years, and inflow coefficients based in agricultural land use for areas not yet urbanized. However, population increase —over 400% in 50 years— and associated urbanization modified original design conditions and present discharges have been doubled, exceeding its capacity. On the other hand, the lowest site of GMZ corresponds to the bed of the river San Juan de Dios (1488 m asl) in the historical center of Guadalajara City; meaning it that the pluvial waters in GMZ —because of the lack of an adequate sewer and the presence of physical barriers like buildings, streets, etc.— run superficially. As a consequence, seasonally floods in many places of the GMZ are common. GMZ (20° 40.5’N, 103°20.8’W; ~700 km2; ~4.5M inhabitants; ~1520 m asl in western Mexico) is located 25 km (N90°) far from La Primavera volcanic complex (LP). LP was emplaced at Late Pleistocene and it is made of lavas, air-fall pumice and ash flows of rhyolitic composition knowed as Tala Tuff (TT): an aphyric non welded ash flow erupted by LP, composed by glassy or aphanitic material pumice dominant (> 90%), with a lesser proportion of sand-sized clasts, lythic gravel and broken crystals. Outcrops of LP extend to the basins surrounding it including the basement of most of the GMZ. Maximum thickness of TT is close to 600 m near LP, at western and southern part of GMZ, whereas in northern and eastern GMZ it can be only a few meters. Interaction of drainage and lithology of TT in GMZ conforms an erosional pattern with dendritic drainage pattern and development of creeks- Many of these creeks have been used as sanitary landfills for municipal waste of refilled with lack of control or selection of the fill material; while new residential developments were constructed over them. In this context, besides the

  17. Estimation of drought and flood recurrence interval from historical discharge data: a case study utilising the power law distribution

    Science.gov (United States)

    Eadie, Chris; Favis-Mortlock, David

    2010-05-01

    The choice of which statistical distribution to fit to historical discharge data is critical when attempting to predict the most extreme flows. It has been shown that depending upon the distribution selected, the calculated return periods can vary dramatically. Cunnane (1985) discussed the factors affecting the choice of distribution for river flow series data, and was able to show that small differences in the Extreme Value Type 1 (Gumbel), Type 2, and Type 3 can lead to large differences in the predicted return period. Indeed this divergence increases as the return period becomes larger: a finding which has obvious implications for fluvial management. Despite this, in many studies which fit a frequency-magnitude distribution to fluvial discharge data, the choice of distribution appears driven by regional convention, or even by some other apparently arbitrary factor. Benson (1968) analysed data for ten US stations, and compared the fit using the log-normal, gamma, Gumbel, log-Gumbel, Hazen and log-Pearson type 3 distributions. On the basis of this study alone, the standard approach to flow frequency estimation in the USA became the fitting of a log-Pearson type 3 (LP3) distribution (US Water Resources Council, 1982). While several other countries have adopted a similar approach, usage of the LP3 distribution is not geographically universal. Hydrologists in the United Kingdom conventionally utilise a fitted generalised logistic distribution for flow frequency estimation (Robson and Reed, 1999) while Chinese hydrologists utilise the log-normal distribution (Singh, 2002). Choice of fitted distribution is obviously crucial, since selecting one distribution rather than another will change the estimated probabilities of future droughts and floods, particularly the largest and rarest events. Malamud et al. (1996) showed that a flood of equivalent size to that experienced on the Mississippi in 1993 has a recurrence interval on the order of 100 years when a power

  18. NASA's Support to Flood Response

    Science.gov (United States)

    Green, D. S.; Murray, J. J.; Stough, T.

    2016-12-01

    The extent of flood and inundation, the impacts on people and infrastructure, and generally the situational awareness on all scales for decision making are areas where NASA is mobilizing scientific results, advanced sensing and technologies, experts and partnerships to support response. NASA has targeted mature application science and ready technology for flood and inundation monitoring and assessment. This includes supporting timely data management and product dissemination with users and partners. Requirements are captured in the form of science-area questions, while solutions measure readiness for use by considering standard tools and approaches that make information more accessible, interoperable, understandable and reliable. The program collaborates with capacity building and areas of education and outreach needed to create and leverage non-traditional partnerships in transdisciplinary areas including socio-economic practice, preparedness and resilience assessment, early warning and forecast response, and emergency management, relief and recovery. The program outcomes also seek alignment with and support to global and community priorities related to water resources and food security. This presentation will examine the achievements of individual projects and the challenges and opportunities of more comprehensive and collaborative teams behind NASA's response to global flooding. Examples from recent event mobilization will be reviewed including to the serious of domestic floods across the south and Midwest United States throughout 2015 and 2016. Progress on the combined use of optical, microwave and SAR remote sensing measurements, topographic and geodetic data and mapping, data sharing practices will be reviewed. Other response case studies will examine global flood events monitored, characterized and supported in various boundary regions and nations. Achievements and future plans will be described for capabilities including global flood modeling, near real

  19. Neotectonics in northeastern Brazil

    Science.gov (United States)

    Bezerra, Francisco Hilario Rego

    The thesis describes neotectonic deformation in the continental intraplate region of northeastern Brazil and explores its links with modern seismicity. The region, which is under E-W-oriented compression and N-S-oriented extension, shows shallow earthquake swarms which last for several years and include 5.0-5.2 mb events. Remote sensing, borehole and geophysical data, in conjunction with field structural information, indicate a continuous faulting process since the Miocene which has reactivated Cretaceous faults and Precambrian shear zones or in places generated new faults which cut across existing structures. Three main sets of faults are recognised across the area: a NE-striking set, a NW-striking set and a N-striking set. The first and the second sets are pervasive and their cross-cutting relationships show that they locally form a conjugate set and display both a strike-slip and a dip-slip component of movement. They have generated troughs filled by as much as 260 m of Cainozoic sediments. Radiocarbon dating shows that some of the faults slipped as recently as 4,041-3,689 cal. yr BP. Although the elevation of coastal deposits is consistent with the predictions of glacioisostatic models for the area, tectonic influence can be detected notably near the Carnaubais fault, where rapid emergence by at least 5 m to the east of Sao Bento occurred 4,080-2,780 cal. yr BP. Secondary ground failure, which includes hydroplastic deformation, liquefaction and landslides, can be seen in Quaternary alluvial sediments and is reported in the historical record. The present data show that the potential for large earthquakes in northeastern Brazil has been underestimated. Empirical relationships using liquefaction and surface rupture point to events of at least Ms=6.8 compared to a maximum mb = 5.2 recorded instrumentally. The finding that NE- and NW-trending faults are favourably orientated for reactivation in relation to the current stress field is of potential value for seismic

  20. Cartography of flood hazard by overflowing rivers using hydraulic modeling and geographic information system: Oued El Harrach case (North of Algeria

    Directory of Open Access Journals (Sweden)

    S. W. Astite

    2015-12-01

    Full Text Available The aim of the present study is the management of flood risk through the use of cartography of flood hazards by overflowing rivers. This cartography is developed using modern simulation tools namely the hydraulic model (HECRAS as well as the Geographic Information System (ArcGis. The study concerns Oued El Harrach (North of Algeria surrounding area which has been subject to several floods causing significant human and material damage. This loss is a consequence of the use flood zones as habitats for people. This can be avoided in the future by use the mapping of the spatial extent of the flood hazard on the land of the Oued El Harrach. Hence the importance of the cartography developed in this study as an essential tool for decision makers in prevention, protection and management of flood risks.

  1. Visualization and Damage Assessment for Flooded Area

    Institute of Scientific and Technical Information of China (English)

    SU Guozhong; YAN Li; LIU Nan; LIU Renyi

    2004-01-01

    A practical method for visualizing flood area and evaluating damage is presented, which consists of two technical approaches: self-programming and adapting commercial GIS platforms. The low-cost and easy-to-use GIS-Based model developed by self-programming can meet current requirements of most local authorities, especially in developing countries. In this model, two cases, non-source flood and source flood, are distinguished and the Seed-spread algorithm suitable for source-flood is discussed; The flood damage is assessed by overlaying the flood area range with thematic maps and other related social and economic data. and all thematic maps are converted to raster format before overlay analysis. Two measures are taken to improve the operation efficiency of speed seed-spread algorithm. The accuracy of the model mainly depends on the resolution and precision of the DEM data, and the accuracy of registering all raster layers and the quality of attribute data.

  2. DRINKING WATER QUALITY IN WELLS FROM AN AREA AFFECTED BY FLOOD EVENTS: CASE STUDY OF CURVATURE SUB-CARPATHIANS, ROMANIA

    Directory of Open Access Journals (Sweden)

    ŞENILĂ M.

    2015-03-01

    Full Text Available The present study evaluates the chemical parameters (inorganic anions and metals of drinking water of twenty-four wells and the presence of Escherichia coli in ten selected wells located in two villages from Buzau and Prahova Counties, in Curvature Sub-Carpathians, Romania, a rural area frequently affected by flood events. Water samples were collected in July 2014. Concerntrations of fluorides, nitrites, chlorides and phosphates were below the maximum allowable concentrations (MACs for drinking water established by European legislation (Drinking Water Directive 98/83/CE in all the analysed samples. Concentration of nitrates exceeded MAC (50 mg L-1 in five samples, while concentration of sulphates exceeded MAC (250 mg L-1 in two samples. Among the analysed metals, Mn exceeded MAC (50 μg L-1 in two samples, while Cu, Pb, Zn, Fe, Na, Cd, Cr, Cu, Ni and As concentrations did not exceeded the corresponding MACs. E. coli (over 2000 UFC 100 mL-1 was found in six water samples. The results show that majority of the studied parameters were below the threshold limits, however in some of the studied wells the water was found to be contaminated both by some chemical pollutants and by E. coli, which prepresent a risk for local population health.

  3. Fault tree analysis for urban flooding.

    Science.gov (United States)

    ten Veldhuis, J A E; Clemens, F H L R; van Gelder, P H A J M

    2009-01-01

    Traditional methods to evaluate flood risk generally focus on heavy storm events as the principal cause of flooding. Conversely, fault tree analysis is a technique that aims at modelling all potential causes of flooding. It quantifies both overall flood probability and relative contributions of individual causes of flooding. This paper presents a fault model for urban flooding and an application to the case of Haarlem, a city of 147,000 inhabitants. Data from a complaint register, rainfall gauges and hydrodynamic model calculations are used to quantify probabilities of basic events in the fault tree. This results in a flood probability of 0.78/week for Haarlem. It is shown that gully pot blockages contribute to 79% of flood incidents, whereas storm events contribute only 5%. This implies that for this case more efficient gully pot cleaning is a more effective strategy to reduce flood probability than enlarging drainage system capacity. Whether this is also the most cost-effective strategy can only be decided after risk assessment has been complemented with a quantification of consequences of both types of events. To do this will be the next step in this study.

  4. Flooding and Schools

    Science.gov (United States)

    National Clearinghouse for Educational Facilities, 2011

    2011-01-01

    According to the Federal Emergency Management Agency, flooding is the nation's most common natural disaster. Some floods develop slowly during an extended period of rain or in a warming trend following a heavy snow. Flash floods can occur quickly, without any visible sign of rain. Catastrophic floods are associated with burst dams and levees,…

  5. Development of an Integrated DHSVM-Flood2D-GPU modeling framework - A Case Study for the Alabama-Coosa-Tallapoosa River Basin

    Science.gov (United States)

    Dullo, T. T.; Kalyanapu, A. J.; Gangrade, S.; Marshall, R.; Islam, S. R.; Ghafoor, S. K.; Kao, S. C.; Preston, B. L.

    2016-12-01

    The objective of this study is to develop an integrated and computationally-efficient hydrologic-hydraulic modeling framework that couples a spatially distributed hydrologic model (DHSVM) with a high-resolution GPU-accelerated flood model (Flood2D-GPU). Taking Alabama-Coosa-Tallapoosa (ACT) river basin as a test bed, hydrologic simulation is conducted using a 90m resolution DHSVM hydrologic model that can be driven by observed precipitation or simulated meteorology from Weather Research Forecasting (WRF) model. The DHSVM hydrograph along with 10m resolution digital elevation and estimated bed roughness are then used to conduct high resolution flood simulation using an accelerated Flood2D-GPU model. A model to model comparison is performed for the Carrollton City, GA, located inside the ACT river basin by examining the difference between the maximum flood inundation extents obtained from Flood2D-GPU and a commonly-used single-CPU Flo-2D model. The comparison shows that Flood2D-GPU can largely reduce the required simulation time while being able to provide similar results to Flo-2D. Our next step is to scale up the simulation framework for larger domain and for more parallel ensemble members utilizing high-performance computing. We expect that this integrated DHSVM-Flood2D-GPU modeling framework can support hydroclimate researchers evaluating the flood risks on our sensitive energy-water infrastructures in a more efficient manner.

  6. Middle Eocene Nummulites and their offshore re-deposition: A case study from the Middle Eocene of the Venetian area, northeastern Italy

    Science.gov (United States)

    Bassi, Davide; Nebelsick, James H.; Puga-Bernabéu, Ángel; Luciani, Valeria

    2013-11-01

    The Middle Eocene Calcari nummulitici formation from northeastern Italy, Venetian area, represents a shallow-marine carbonate ramp developed on the northern Tethyan margin. In the Monti Berici area, its main components are larger foraminifera and coralline red algal communities that constitute thick carbonate sedimentary successions. Middle ramp and proximal outer ramp environments are recognized using component relationships, biofacies and sedimentary features. The middle-ramp is characterized by larger flattened-lenticular Nummulites on palaeohighs between which rhodoliths formed. Larger Nummulites palaeohighs containing Nummulites millecaput, Nummulites crassus, Nummulites discorbinus and Nummulites cf. gizehensis developed more basin-wards. The following relatively quiet environments of basin-wards of the palaeohighs represent areas of maximum carbonate production. The transition between the distal middle- and the proximal outer-ramp settings is marked in the study area by a large erosional surface which is interpreted to have been formed as a result of an erosive channel body filled in by deposits re-sedimented from shallower depths. These off-shore re-sedimented channelized deposits, ascribed to the Shallow Benthic Zone SBZ 15, lying on hemipelagic marls (planktonic foraminiferal zone E9 (P11)) allow for a biostratigraphic correlation to the Late Lutetian. The studied deposits, represented by packstone to rudstones, were displaced whilst still unlithified. The Lutetian-Bartonian regression along with the local tectonic activity promoted the production of a high amount of biogenic shallow-water carbonates mainly produced in the Mossano middle-ramp settings. These prograded towards the basinal areas with high-sedimentation rate of carbonate deposits characterized by the larger Nummulites rudstones. Such high amounts of sediment led to sediment instability which potentially could be mobilized either by return currents due to occasional major storms or by

  7. Capability of a regional climate model to simulate climate variables requested for water balance computation: a case study over northeastern France

    Science.gov (United States)

    Boulard, Damien; Castel, Thierry; Camberlin, Pierre; Sergent, Anne-Sophie; Bréda, Nathalie; Badeau, Vincent; Rossi, Aurélien; Pohl, Benjamin

    2016-05-01

    This paper documents the capability of the ARW/WRF regional climate model to regionalize near-surface atmospheric variables at high resolution (8 km) over Burgundy (northeastern France) from daily to interannual timescales. To that purpose, a 20-year continuous simulation (1989-2008) was carried out. The WRF model driven by ERA-Interim reanalyses was compared to in situ observations and a mesoscale atmospheric analyses system (SAFRAN) for five near-surface variables: precipitation, air temperature, wind speed, relative humidity and solar radiation, the last four variables being used for the calculation of potential evapotranspiration (ET0). Results show a significant improvement upon ERA-Interim. This is due to a good skill of the model to reproduce the spatial distribution for all weather variables, in spite of a slight over-estimation of precipitation amounts mostly during the summer convective season, and wind speed during winter. As compared to the Météo-France observations, WRF also improves upon SAFRAN analyses, which partly fail at showing realistic spatial distributions for wind speed, relative humidity and solar radiation—the latter being strongly underestimated. The SAFRAN ET0 is thus highly under-estimated too. WRF ET0 is in better agreement with observations. In order to evaluate WRF's capability to simulate a reliable ET0, the water balance of thirty Douglas-fir stands was computed using a process-based model. Three soil water deficit indexes corresponding to the sum of the daily deviations between the relative extractible water and a critical value of 40 % below which the low soil water content affects tree growth, were calculated using the nearest weather station, SAFRAN analyses weather data, or by merging observation and WRF weather variables. Correlations between Douglas-fir growth and the three estimated soil water deficit indexes show similar results. These results showed through the ET0 estimation and the relation between mean annual SWDI

  8. Lithostratigraphy of the Kalahari Group in northeastern Namibia

    Science.gov (United States)

    Wanke, Heike; Wanke, Ansgar

    2007-08-01

    The Kalahari Group in northeastern Namibia consists of terrestrial sediments deposited in a tectonically active basin that was formed by flexural uplift of the African continental margin and independent structures related to rifting. The thickness of the sequence varies from a few meters to around 400 m. Greatest thicknesses occur where the NW-SE trending Kalahari basin axis conjugates with NE-SW trending grabens. Repeated phases of flooding and desiccation dominate the depositional environments of the Kalahari Group in northeastern Namibia. Associations of lithofacies allow recognition of distinct depositional settings such as proximal debris flows, braided streams and sand fans, and pans and sandflats. The northeastern Namibian Kalahari Group rests unconformable on the pre-Kalahari surface which showed a relatively pronounced relief in the Epukiro area. The succession starts with conglomerates, breccias and pebbly sandstones, followed by carbonates, sandstones of various maturities, and silcretes. Ferruginous sandstones and ferricretes occur locally. The onset of Kalahari Group deposition was likely a basin-wide event and therefore the basal lithostratigraphic units can be correlated with confidence. Conversely, the correlation of the succeeding lithostratigraphic units remains fairly speculative.

  9. Fatal outbreak from consuming Xanthium strumarium seedlings during time of food scarcity in northeastern Bangladesh.

    Directory of Open Access Journals (Sweden)

    Emily S Gurley

    Full Text Available BACKGROUND: An outbreak characterized by vomiting and rapid progression to unconsciousness and death was reported in Sylhet Distrct in northeastern Bangladesh following destructive monsoon floods in November 2007. METHODS AND FINDINGS: We identified cases presenting to local hospitals and described their clinical signs and symptoms. We interviewed patients and their families to collect illness histories and generate hypotheses about exposures associated with disease. An epidemiological study was conducted in two outbreak villages to investigate risk factors for developing illness. 76 patients were identified from 9 villages; 25% (19/76 died. Common presenting symptoms included vomiting, elevated liver enzymes, and altered mental status. In-depth interviews with 33 cases revealed that 31 (94% had consumed ghagra shak, an uncultivated plant, in the hours before illness onset. Ghagra shak was consumed as a main meal by villagers due to inaccessibility of other foods following destructive monsoon flooding and rises in global food prices. Persons who ate this plant were 34.2 times more likely (95% CI 10.2 to 115.8, p-value<0.000 than others to develop vomiting and unconsciousness during the outbreak in our multivariate model. Ghagra shak is the local name for Xanthium strumarium, or common cocklebur. CONCLUSIONS: The consumption of Xanthium strumarium seedlings in large quantities, due to inaccessibility of other foods, caused this outbreak. The toxic chemical in the plant, carboxyatratyloside, has been previously described and eating X. strumarium seeds and seedlings has been associated with fatalities in humans and livestock. Unless people are able to meet their nutritional requirements with safe foods, they will continue to be at risk for poor health outcomes beyond undernutrition.

  10. Fatal Outbreak from Consuming Xanthium strumarium Seedlings during Time of Food Scarcity in Northeastern Bangladesh

    Science.gov (United States)

    Gurley, Emily S.; Rahman, Mahmudur; Hossain, M. Jahangir; Nahar, Nazmun; Faiz, M. Abul; Islam, Nazrul; Sultana, Rebeca; Khatun, Selina; Uddin, Mohammad Zashim; Haider, M. Sabbir; Islam, M. Saiful; Ahmed, Be-Nazir; Rahman, Muhammad Waliur; Mondal, Utpal Kumar; Luby, Stephen P.

    2010-01-01

    Background An outbreak characterized by vomiting and rapid progression to unconsciousness and death was reported in Sylhet Distrct in northeastern Bangladesh following destructive monsoon floods in November 2007. Methods and Findings We identified cases presenting to local hospitals and described their clinical signs and symptoms. We interviewed patients and their families to collect illness histories and generate hypotheses about exposures associated with disease. An epidemiological study was conducted in two outbreak villages to investigate risk factors for developing illness. 76 patients were identified from 9 villages; 25% (19/76) died. Common presenting symptoms included vomiting, elevated liver enzymes, and altered mental status. In-depth interviews with 33 cases revealed that 31 (94%) had consumed ghagra shak, an uncultivated plant, in the hours before illness onset. Ghagra shak was consumed as a main meal by villagers due to inaccessibility of other foods following destructive monsoon flooding and rises in global food prices. Persons who ate this plant were 34.2 times more likely (95% CI 10.2 to 115.8, p-value<0.000) than others to develop vomiting and unconsciousness during the outbreak in our multivariate model. Ghagra shak is the local name for Xanthium strumarium, or common cocklebur. Conclusions The consumption of Xanthium strumarium seedlings in large quantities, due to inaccessibility of other foods, caused this outbreak. The toxic chemical in the plant, carboxyatratyloside, has been previously described and eating X. strumarium seeds and seedlings has been associated with fatalities in humans and livestock. Unless people are able to meet their nutritional requirements with safe foods, they will continue to be at risk for poor health outcomes beyond undernutrition. PMID:20305785

  11. Deployment and use of mobile phone technology for real-time reporting of fever cases and malaria treatment failure in areas of declining malaria transmission in Muheza district north-eastern Tanzania.

    Science.gov (United States)

    Francis, Filbert; Ishengoma, Deus S; Mmbando, Bruno P; Rutta, Acleus S M; Malecela, Mwelecele N; Mayala, Benjamin; Lemnge, Martha M; Michael, Edwin

    2017-08-01

    Early detection of febrile illnesses at community level is essential for improved malaria case management and control. Currently, mobile phone-based technology has been commonly used to collect and transfer health information and services in different settings. This study assessed the applicability of mobile phone-based technology in real-time reporting of fever cases and management of malaria by village health workers (VHWs) in north-eastern Tanzania. The community mobile phone-based disease surveillance and treatment for malaria (ComDSTM) platform, combined with mobile phones and web applications, was developed and implemented in three villages and one dispensary in Muheza district from November 2013 to October 2014. A baseline census was conducted in May 2013. The data were uploaded on a web-based database and updated during follow-up home visits by VHWs. Active and passive case detection (ACD, PCD) of febrile cases were done by VHWs and cases found positive by malaria rapid diagnostic test (RDT) were given the first dose of artemether-lumefantrine (AL) at the dispensary. Each patient was visited at home by VHWs daily for the first 3 days to supervise intake of anti-malarial and on day 7 to monitor the recovery process. The data were captured and transmitted to the database using mobile phones. The baseline population in the three villages was 2934 in 678 households. A total of 1907 febrile cases were recorded by VHWs and 1828 (95.9%) were captured using mobile phones. At the dispensary, 1778 (93.2%) febrile cases were registered and of these, 84.2% were captured through PCD. Positivity rates were 48.2 and 45.8% by RDT and microscopy, respectively. Nine cases had treatment failure reported on day 7 post-treatment and adherence to treatment was 98%. One patient with severe febrile illness was referred to Muheza district hospital. The study showed that mobile phone-based technology can be successfully used by VHWs in surveillance and timely reporting of fever

  12. Hazard Assessment of Glacial Lake Outburst Flood and Potential of ICTs for Coping: A Case of Eastern Himalaya of Nepal

    Science.gov (United States)

    Bhattarai, D. R.

    2015-12-01

    Retreat of glaciers and formation of glacial lakes in Nepal Himalaya have been reported to be related with the temperature rise in the region. Glacier Lake Outburst Floods (GLOF) are the growing climate induced hazards in the Himalaya. GLOF has increased the vulnerability of community and fragile ecosystem in the mountain valleys. This study has analyzed the potential impacts from GLOF in the highland of eastern Nepal and the potential role of Information Communication Technologies (ICT) to cope with such impacts. I analyzed the trend of climatic pattern (temperature and precipitation) of the Eastern Himalaya Region of Nepal available from the Department of Hydrology and Meteorology, Government of Nepal, and prepared the latest location map of the glacial lakes using google earth and ArcGIS applications in the highland of the Kanchanjungha Conservation Area of the region. Tiptala glacial lake, located at an elevation of 4950 m, within the conservation area, was selected for the GLOF hazard assessment. I used semi-structured questionnaire survey and key informants' interviews in the community in order to assess the potential hazard of GLOF. With the varying sizes, 46 glacial lakes were located in the region, which covers over 2.57 sq. km in total. Though the larger portion of the downstream area of the Tiptala glacial lake fall in the remote location away from major residential area, few villages, major pasture lands for Yaks, foot trails, and several bridges across the Tamor River below the lake are in risk of GLOF. Poor access due to extreme geographical remoteness and capacity to afford the modern technologies in the community are the major limiting factor to the knowledge and information about the climate change and related impacts. Modern ICTs has high potential to reduce the risk of climate related hazards in the remote area by information dissemination and awareness.

  13. Coastal flooding: impact of waves on storm surge during extremes - a case study for the German Bight

    Science.gov (United States)

    Staneva, Joanna; Wahle, Kathrin; Koch, Wolfgang; Behrens, Arno; Fenoglio-Marc, Luciana; Stanev, Emil V.

    2016-11-01

    This study addresses the impact of wind, waves, tidal forcing and baroclinicity on the sea level of the German Bight during extreme storm events. The role of wave-induced processes, tides and baroclinicity is quantified, and the results are compared with in situ measurements and satellite data. A coupled high-resolution modelling system is used to simulate wind waves, the water level and the three-dimensional hydrodynamics. The models used are the wave model WAM and the circulation model GETM. The two-way coupling is performed via the OASIS3-MCT coupler. The effects of wind waves on sea level variability are studied, accounting for wave-dependent stress, wave-breaking parameterization and wave-induced effects on vertical mixing. The analyses of the coupled model results reveal a closer match with observations than for the stand-alone circulation model, especially during the extreme storm Xaver in December 2013. The predicted surge of the coupled model is significantly enhanced during extreme storm events when considering wave-current interaction processes. This wave-dependent approach yields a contribution of more than 30 % in some coastal areas during extreme storm events. The contribution of a fully three-dimensional model compared with a two-dimensional barotropic model showed up to 20 % differences in the water level of the coastal areas of the German Bight during Xaver. The improved skill resulting from the new developments justifies further use of the coupled-wave and three-dimensional circulation models in coastal flooding predictions.

  14. What are the hydro-meteorological controls on flood characteristics?

    Science.gov (United States)

    Nied, Manuela; Schröter, Kai; Lüdtke, Stefan; Nguyen, Viet Dung; Merz, Bruno

    2017-02-01

    Flood events can be expressed by a variety of characteristics such as flood magnitude and extent, event duration or incurred loss. Flood estimation and management may benefit from understanding how the different flood characteristics relate to the hydrological catchment conditions preceding the event and to the meteorological conditions throughout the event. In this study, we therefore propose a methodology to investigate the hydro-meteorological controls on different flood characteristics, based on the simulation of the complete flood risk chain from the flood triggering precipitation event, through runoff generation in the catchment, flood routing and possible inundation in the river system and floodplains to flood loss. Conditional cumulative distribution functions and regression tree analysis delineate the seasonal varying flood processes and indicate that the effect of the hydrological pre-conditions, i.e. soil moisture patterns, and of the meteorological conditions, i.e. weather patterns, depends on the considered flood characteristic. The methodology is exemplified for the Elbe catchment. In this catchment, the length of the build-up period, the event duration and the number of gauges undergoing at least a 10-year flood are governed by weather patterns. The affected length and the number of gauges undergoing at least a 2-year flood are however governed by soil moisture patterns. In case of flood severity and loss, the controlling factor is less pronounced. Severity is slightly governed by soil moisture patterns whereas loss is slightly governed by weather patterns. The study highlights that flood magnitude and extent arise from different flood generation processes and concludes that soil moisture patterns as well as weather patterns are not only beneficial to inform on possible flood occurrence but also on the involved flood processes and resulting flood characteristics.

  15. Flood Resilient Systems and their Application for Flood Resilient Planning

    Science.gov (United States)

    Manojlovic, N.; Gabalda, V.; Antanaskovic, D.; Gershovich, I.; Pasche, E.

    2012-04-01

    SMARTeST. A web based three tier advisory system FLORETO-KALYPSO (http://floreto.wb.tu-harburg.de/, Manojlovic et al, 2009) devoted to support decision-making process at the building level has been further developed to support multi-scale decision making on resilient systems, improving the existing data mining algorithms of the Business Logic tier. Further tuning of the algorithms is to be performed based on the new developments and findings in applicability and efficiency of different FRe Technology for different flood typologies. The first results obtained at the case studies in Greater Hamburg, Germany indicate the potential of this approach to contribute to the multiscale resilient planning on the road to flood resilient cities. FIAC (2007): "Final report form the Awareness and Assistance Sub-committee", FIAC, Scottish Government Zevenbergen C. et al (2008) "Challenges in urban flood management: travelling across spatial and temporal scales", Journal of FRM Volume 1 Issue 2, p 81-88 Manojlovic N., et al (2009): "Capacity Building in FRM through a DSS Utilising Data Mining Approach", Proceed. 8th HIC, Concepcion, Chile, January, 2009

  16. Flood Mitigation of Nyando River Using Duflow Modelling

    Directory of Open Access Journals (Sweden)

    J. Joleha

    2009-01-01

    Full Text Available Duflow surface water hydrodynamic model has been applied using a case study from Nyando catchment in the western part of Kenya in Africa to simulate various extreme flood behaviours and their retardation levels by using selected structural measures as flood mitigation techniques. The objective of this case study was to establish a design flood recommendable for mitigation, and to identify the most cost effective flood mitigation structure. Various design flows are simulated against the different proposed structures hence, the optimal structure can be recommended when economical, social and environmental constraints are considered in the decision making process. The proposed four flood mitigation structures flood plain extension, embankment (dykes, channel by-pass, and green-storage were simulated for 20-year recurrence interval flood to determine their individual responses in storing excess water. The result shows that building a green-storage is the best and optimal structure for flood mitigation.

  17. Designing an 'expert knowledge' based approach for the quantification of historical floods - the case study of the Kinzig catchment in Southwest Germany

    Science.gov (United States)

    Bösmeier, Annette; Glaser, Rüdiger; Stahl, Kerstin; Himmelsbach, Iso; Schönbein, Johannes

    2017-04-01

    Future estimations of flood hazard and risk for developing optimal coping and adaption strategies inevitably include considerations of the frequency and magnitude of past events. Methods of historical climatology represent one way of assessing flood occurrences beyond the period of instrumental measurements and can thereby substantially help to extend the view into the past and to improve modern risk analysis. Such historical information can be of additional value and has been used in statistical approaches like Bayesian flood frequency analyses during recent years. However, the derivation of quantitative values from vague descriptive information of historical sources remains a crucial challenge. We explored possibilities of parametrization of descriptive flood related data specifically for the assessment of historical floods in a framework that combines a hermeneutical approach with mathematical and statistical methods. This study forms part of the transnational, Franco-German research project TRANSRISK2 (2014 - 2017), funded by ANR and DFG, with the focus on exploring the floods history of the last 300 years for the regions of Upper and Middle Rhine. A broad data base of flood events had been compiled, dating back to AD 1500. The events had been classified based on hermeneutical methods, depending on intensity, spatial dimension, temporal structure, damages and mitigation measures associated with the specific events. This indexed database allowed the exploration of a link between descriptive data and quantitative information for the overlapping time period of classified floods and instrumental measurements since the end of the 19th century. Thereby, flood peak discharges as a quantitative measure of the severity of a flood were used to assess the discharge intervals for flood classes (upper and lower thresholds) within different time intervals for validating the flood classification, as well as examining the trend in the perception threshold over time

  18. Flash flood characterisation of the Haor area of Bangladesh

    Science.gov (United States)

    Bhattacharya, B.; Suman, A.

    2012-04-01

    Haors are large bowl-shaped flood plain depressions located mostly in north-eastern part of Bangladesh covering about 25% of the entire region. During dry season haors are used for agriculture and during rainy season it is used as fisheries. Haors have profound ecological importance. About 8000 migratory wild birds visit the area annually. Some of the haors are declared at Ramsar sites. Haors are frequently affected by the flash floods due to hilly topography and steep slope of the rivers draining the area. These flash floods spill onto low-lying flood plain lands in the region, inundating crops, damaging infrastructure by erosion and often causing loss of lives and properties. Climate change is exacerbating the situation. For appropriate risk mitigation mechanism it is necessary to explore flood characteristics of that region. The area is not at all studied well. Under a current project a numerical 1D2D model based on MIKE Flood is developed to study the flooding characteristics and estimate the climate change impacts on the haor region. Under this study the progression of flood levels at some key haors in relation to the water level data at specified gauges in the region is analysed. As the region is at the border with India so comparing with the gauges at the border with India is carried out. The flooding in the Haor area is associated with the rainfall in the upstream catchment in India (Meghalaya, Barak and Tripura basins in India). The flood propagation in some of the identified haors in relation to meteorological forcing in the three basins in India is analysed as well. Subsequently, a ranking of haors is done based on individual risks. Based on the IPCC recommendation the precipitation scenario in the upstream catchments under climate change is considered. The study provides the fundamental inputs for preparing a flood risk management plan of the region.

  19. Delivery of Ecosystem Benefits at the Urban-Suburban Interface: A Case Study of Flood Protection in the Woonasquatucket River Watershed

    Science.gov (United States)

    Urbanization exacerbates flooding by increasing surface runoff and decreasing surface roughness. Restoring wetlands can enhance flood protection while providing a suite of co-benefits such as temperature regulation and access to open space. Spatial modeling of the delivery of flo...

  20. How much physical complexity is needed to model flood inundation?

    OpenAIRE

    Neal, J.; Bates, P; Villanueva, I; Wright, N.; Willis, T; Fewtrell, T

    2011-01-01

    Two-dimensional flood inundation models are widely used tools for flood hazard mapping and an essential component of statutory flood risk management guidelines in many countries. Yet, we still do not know how much physical complexity a flood inundation model needs for a given problem. Here, three two-dimensional explicit hydraulic models, which can be broadly defined as simulating diffusive, inertial or shallow water waves, have been benchmarked using test cases from a recent Environment Agen...

  1. Territory Planning Perspective in Flood-Prone Areas in Riga

    Directory of Open Access Journals (Sweden)

    Dace Berzina

    2016-04-01

    Full Text Available The flood risk problems in Riga city due to global warming and climate change are studied based on the European experience incorporated in European and Latvian legislation. Amendment to the Protection Zone Law of Latvia is studied and compared with the likelihood of the flood risk and development possibilities in the flood risk zones. The study focuses on the case of the Vecdaugava River neighbourhood as the potential flood risk zone in Riga city.

  2. Casing Pipe Plugging Method of Flood Discharging Tunnel in Tailing Dam%尾矿库排洪隧洞套管封堵法

    Institute of Scientific and Technical Information of China (English)

    罗冬兰; 胡虎

    2012-01-01

    The plugging method of flood discharging tunnel commonly used in tailing dam at present requires personal coming into the flood discharging system to deal with. Hence,the plugging project needs to be finished at drying seasons. When an accident occurred or security risks existed in the drainage system,the plugging construction in the cave is largely limited in considerations of personal safety. In view of these shortcomings,the casing pipe plugging method with combination of temporary support by steel casing pipe and concrete sealing was proposed,which has been applied into the emergency rescue of tailings leakage in Yinshan Lead-zinc Mine. In this accident,the tailings leak risks are relieved rapidly and safely by adopting the casing pipe plugging,and the system works well till now. The plugging method provides a safe construction environment before personals come into the cave,and it is ideal for emergency rescue in the tailings leakage accident. Meanwhile,this method provides a fast,safe and effective sealing method and idea for dealing with the old security risks in flood discharging system of tailings dam.%目前常用的尾矿库排洪隧洞封堵方法,均需施工人员直接进入排洪系统中作业,因此,一般选择干旱季节进行封堵施工;而当排洪系统出现事故或排洪系统存在安全隐患时,出于抢险和人身安全的考虑,其洞内封堵施工受到限制.针对常用封堵法的不足,提出了利用钢套管做临时支挡及混凝土封堵相结合的套管封堵法,并运用到银山铅锌矿尾矿库尾砂泄露抢险中.失事排洪系统通过采用套管封堵,漏砂事故得到迅速安全解决,至今运行良好.该封堵法为施工人员进洞前提供了安全施工环境,非常适合尾矿库漏砂事故后排洪系统的抢险封堵;同时,为有历史遗留安全隐患的尾矿库排洪系统提供了一种快速、安全、有效的封堵方法和思路.

  3. Reconstruction of the 1945 Wieringermeer Flood

    Science.gov (United States)

    Hoes, O. A. C.; Hut, R. W.; van de Giesen, N. C.; Boomgaard, M.

    2013-03-01

    The present state-of-the-art in flood risk assessment focuses on breach models, flood propagation models, and economic modelling of flood damage. However, models need to be validated with real data to avoid erroneous conclusions. Such reference data can either be historic data, or can be obtained from controlled experiments. The inundation of the Wieringermeer polder in the Netherlands in April 1945 is one of the few examples for which sufficient historical information is available. The objective of this article is to compare the flood simulation with flood data from 1945. The context, the breach growth process and the flood propagation are explained. Key findings for current flood risk management addresses the importance of the drainage canal network during the inundation of a polder, and the uncertainty that follows from not knowing the breach growth parameters. This case study shows that historical floods provide valuable data for the validation of models and reveal lessons that are applicable in current day flood risk management.

  4. Future flood losses in major coastal cities

    Science.gov (United States)

    Hallegatte, Stephane; Green, Colin; Nicholls, Robert J.; Corfee-Morlot, Jan

    2013-09-01

    Flood exposure is increasing in coastal cities owing to growing populations and assets, the changing climate, and subsidence. Here we provide a quantification of present and future flood losses in the 136 largest coastal cities. Using a new database of urban protection and different assumptions on adaptation, we account for existing and future flood defences. Average global flood losses in 2005 are estimated to be approximately US$6billion per year, increasing to US$52billion by 2050 with projected socio-economic change alone. With climate change and subsidence, present protection will need to be upgraded to avoid unacceptable losses of US$1trillion or more per year. Even if adaptation investments maintain constant flood probability, subsidence and sea-level rise will increase global flood losses to US$60-63billion per year in 2050. To maintain present flood risk, adaptation will need to reduce flood probabilities below present values. In this case, the magnitude of losses when floods do occur would increase, often by more than 50%, making it critical to also prepare for larger disasters than we experience today. The analysis identifies the cities that seem most vulnerable to these trends, that is, where the largest increase in losses can be expected.

  5. High frequency of resistance to the drugs isoniazid and rifampicin among tuberculosis cases in the city of Cabo de Santo Agostinho, an urban area in Northeastern Brazil

    OpenAIRE

    Baliza,Marcilio; Bach,Artur Henrique; Queiroz,Gabriel Lobo de; Melo,Inês Cardoso; Carneiro,Maria Madileuza; de Albuquerque, Maria de Fátima Pessoa Militão; Suffys, Philip; Rodrigues, Laura; Ximenes,Ricardo; Lucena-Silva,Norma

    2008-01-01

    The objective of the present study was to investigate the frequency and risk factors for developing multidrug-resistant tuberculosis in Cabo de Santo Agostinho, PE. This was a prospective study conducted from 2000 to 2003, in which suspected cases were investigated using bacilloscopy and culturing. Out of 232 confirmed cases of tuberculosis, culturing and antibiotic susceptibility tests were performed on 174. Thirty-five of the 174 cultures showed resistance to all drugs. The frequencies of p...

  6. King Tide floods in Tuvalu

    Science.gov (United States)

    Lin, C.-C.; Ho, C.-R.; Cheng, Y.-H.

    2013-05-01

    The spatial and temporal distributions of sea level rise present regional floods in some certain areas. The low-lying island countries are obviously the spots affected severely. Tuvalu, an atoll island country located in the south-west Pacific Ocean, is suffering the devastating effects of losing life, property, and intending migration caused by floods. They blame the regional flooding to King Tide, a term used but not clearly identified by Pacific islanders. In this study, we clarify what King Tide is first. By the tide gauge and topography data, we estimated the reasonable value of 3.2 m as the threshold of King Tide. This definition also fits to the statement by National Oceanic and Atmospheric Administration (NOAA) of King Tide occurring once or twice a year. In addition, We cross validate the 19 yr data of tide gauge and satellite altimeter (1993-2012), the correlation coefficient indicates King Tide phenomenon is considerable connected to warm water mass. The 28 King Tide events revealed the fact that flooding can be referenced against spring tide levels, so can it be turned up by warm water mass. The warm water mass pushes up sea level; once spring tide, storm surge, or other climate variability overlaps it, the rising sea level might overflow and so has been called "King Tide" for the floods in Tuvalu. This study provides more understanding of the signals of King Tide and an island country case study of regional sea level rise.

  7. Supply and demand analysis for flood insurance by using logistic regression model: case study at Citarum watershed in South Bandung, West Java, Indonesia

    Science.gov (United States)

    Sidi, P.; Mamat, M.; Sukono; Supian, S.

    2017-01-01

    Floods have always occurred in the Citarum river basin. The adverse effects caused by floods can cover all their property, including the destruction of houses. The impact due to damage to residential buildings is usually not small. Indeed, each of flooding, the government and several social organizations providing funds to repair the building. But the donations are given very limited, so it cannot cover the entire cost of repair was necessary. The presence of insurance products for property damage caused by the floods is considered very important. However, if its presence is also considered necessary by the public or not? In this paper, the factors that affect the supply and demand of insurance product for damaged building due to floods are analyzed. The method used in this analysis is the ordinal logistic regression. Based on the analysis that the factors that affect the supply and demand of insurance product for damaged building due to floods, it is included: age, economic circumstances, family situations, insurance motivations, and lifestyle. Simultaneously that the factors affecting supply and demand of insurance product for damaged building due to floods mounted to 65.7%.

  8. Copula-Based Bivariate Flood Frequency Analysis in a Changing Climate-A Case Study in the Huai River Basin, China

    Institute of Scientific and Technical Information of China (English)

    Kai Duan; Yadong Mei; Liping Zhang

    2016-01-01

    ABSTRACT:Copula-based bivariate frequency analysis can be used to investigate the changes in flood characteristics in the Huai River Basin that could be caused by climate change. The univariate distribu-tions of historical flood peak, maximum 3-day and 7-day volumes in 1961–2000 and future values in 2061–2100 projected from two GCMs (CSIRO-MK3.5 and CCCma-CGCM3.1) under A2, A1B and B1 emission scenarios are analyzed and compared. Then, bivariate distributions of peaks and volumes are constructed based on the copula method and possible changes in joint return periods are characterized. Results indicate that the Clayton copula is more appropriate for historical and CCCma-CGCM3.1 simu-lating flood variables, while that of Frank and Gumbel are better fitted to CSIRO-MK3.5 simulations. The variations of univariate and bivariate return periods reveal that flood characteristics may be more sensi-tive to different GCMs than different emission scenarios. Between the two GCMs, CSIRO-MK3.5 evi-dently predicts much more severe flood conditions in future, especially under B1 scenario, whereas CCCma-CGCM3.1 generally suggests contrary changing signals. This study corroborates that copulas can serve as a viable and flexible tool to connect univariate marginal distributions of flood variables and quantify the associated risks, which may provide useful information for risk-based flood control.

  9. After the flood is before the next flood - post event review of the Central European Floods of June 2013. Insights, recommendations and next steps for future flood prevention

    Science.gov (United States)

    Szoenyi, Michael; Mechler, Reinhard; McCallum, Ian

    2015-04-01

    perception and understanding of risk in the population. • Residual risk and the levee shadow effect - why the population "felt safe." • What is the overload case and how to implement it in flood protection systems? • Decision-making for the future under uncertainty - how to design to acceptable flood protection levels if we haven't seen yet what's physically possible. 3. How to protect - practical examples Finally, we outline practical examples for reducing the loss burden and risk over time. • "Flood protection hierarchy" - from location choice under a hazard perspective to mobile flood protection. • Risk-based approach and identification of critical infrastructure. • Integrated flood risk management in theory and practical application. • Role of insurance.

  10. 3-D hydrodynamic modelling of flood impacts on a building and indoor flooding processes

    Science.gov (United States)

    Gems, Bernhard; Mazzorana, Bruno; Hofer, Thomas; Sturm, Michael; Gabl, Roman; Aufleger, Markus

    2016-06-01

    Given the current challenges in flood risk management and vulnerability assessment of buildings exposed to flood hazards, this study presents three-dimensional numerical modelling of torrential floods and its interaction with buildings. By means of a case study application, the FLOW-3D software is applied to the lower reach of the Rio Vallarsa torrent in the village of Laives (Italy). A single-family house on the flood plain is therefore considered in detail. It is exposed to a 300-year flood hydrograph. Different building representation scenarios, including an entire impervious building envelope and the assumption of fully permeable doors, light shafts and windows, are analysed. The modelling results give insight into the flooding process of the building's interior, the impacting hydrodynamic forces on the exterior and interior walls, and further, they quantify the impact of the flooding of a building on the flow field on the surrounding flood plain. The presented study contributes to the development of a comprehensive physics-based vulnerability assessment framework. For pure water floods, this study presents the possibilities and limits of advanced numerical modelling techniques within flood risk management and, thereby, the planning of local structural protection measures.

  11. Flood Mapping Using InSAR Coherence Map

    Science.gov (United States)

    Selmi, S.; Ben Abdallah, W.; Abdelfatteh, R.

    2014-09-01

    Classic approaches for the detection of flooded areas are based on a static analysis of optical images and/or SAR data during and after the event. In this paper, we aim to extract the flooded zones by using the SAR image coupled with the InSAR coherence. A new formulation of the ratio approach for flood detection is given considering InSAR coherence. Our contribution is to take advantage from the coherence map provided using the InSAR pairs (one before and one after the event) to enhance the detection of flooded areas. We explore the fact that the coherence values during and after the flood are mainly differents on the flooded zones and we give a more suitable flood decision rule using this assumption. The proposed approach is tested and validated in the case of the flood taken place in 2005 in the region of Kef in Tunisia.

  12. The Emergence of Flood Insurance in Canada: Navigating Institutional Uncertainty.

    Science.gov (United States)

    Thistlethwaite, Jason

    2016-08-11

    Flood insurance has remained unavailable in Canada based on an assessment that it lacks economic viability. In response to Canada's costliest flood event to date in 2013, the Canadian insurance industry has started to develop a framework to expand existing property insurance to cover flood damage. Research on flood insurance has overlooked why and how insurance systems transition to expand insurance coverage without evidence of economic viability. This article will address this gap through a case study on the emergence of flood insurance in Canada, and the approach to its expansion. Between 2013 and 2016, insurance industry officials representing over 60% of premiums collected in Canada were interviewed. These interviews revealed that flood insurance is being expanded in response to institutional pressure, specifically external stakeholder expectations that the insurance industry will adopt a stronger role in managing flood risk through coverage of flood damage. Further evidence of this finding is explored by assessing the emergence of a unique flood insurance model that involves a risk-adjusted and optional product along with an expansion of government policy supporting flood risk mitigation. This approach attempts to balance industry concerns about economic viability with institutional pressure to reduce flood risk through insurance. This analysis builds on existing research by providing the first scholarly analysis of flood insurance in Canada, important "empirical" teeth to existing conceptual analysis on the availability of flood insurance, and the influence of institutional factors on risk analysis within the insurance sector.

  13. South China Flooded

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Vehicles traverse a flooded street in Liuzhou, guangxi zhuang Autonomous Region, on May 19.heavy rainstorms repeatedly struck China this month, triggering floods, mudflows and landslides. hunan, guangdong and Jiangxi provinces and Chongqing Municipality were the worst hit.

  14. Base Flood Elevation

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The National Flood Hazard Layer (NFHL) data incorporates all Digital Flood Insurance Rate Map(DFIRM) databases published by FEMA, and any Letters Of Map Revision...

  15. Flood Control Structures

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The National Flood Hazard Layer (NFHL) data incorporates all Digital Flood Insurance Rate Map(DFIRM) databases published by FEMA, and any Letters Of Map Revision...

  16. Flooding: Prioritizing protection?

    Science.gov (United States)

    Peduzzi, Pascal

    2017-09-01

    With climate change, urban development and economic growth, more assets and infrastructures will be exposed to flooding. Now research shows that investments in flood protection are globally beneficial, but have varied levels of benefit locally.

  17. Flood Hazard Area

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The National Flood Hazard Layer (NFHL) data incorporates all Digital Flood Insurance Rate Map(DFIRM) databases published by FEMA, and any Letters Of Map Revision...

  18. Flood Hazard Boundaries

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The National Flood Hazard Layer (NFHL) data incorporates all Digital Flood Insurance Rate Map(DFIRM) databases published by FEMA, and any Letters Of Map Revision...

  19. High frequency of resistance to the drugs isoniazid and rifampicin among tuberculosis cases in the city of Cabo de Santo Agostinho, an urban area in Northeastern Brazil.

    Science.gov (United States)

    Baliza, Marcilio; Bach, Artur Henrique; Queiroz, Gabriel Lobo de; Melo, Inês Cardoso; Carneiro, Maria Madileuza; Albuquerque, Maria de Fátima Pessoa Militão de; Suffys, Philip; Rodrigues, Laura; Ximenes, Ricardo; Lucena-Silva, Norma

    2008-01-01

    The objective of the present study was to investigate the frequency and risk factors for developing multidrug-resistant tuberculosis in Cabo de Santo Agostinho, PE. This was a prospective study conducted from 2000 to 2003, in which suspected cases were investigated using bacilloscopy and culturing. Out of 232 confirmed cases of tuberculosis, culturing and antibiotic susceptibility tests were performed on 174. Thirty-five of the 174 cultures showed resistance to all drugs. The frequencies of primary and acquired resistance to any drug were 14% and 50% respectively, while the frequencies of primary and acquired multidrug resistance were 8.3% and 40%. Previous tuberculosis treatment and abandonment of treatment were risk factors for drug resistance. The high levels of primary and acquired resistance to the combination of isoniazid and rifampicin contributed towards the difficulties in controlling tuberculosis transmission in the city.

  20. Flood Risk Regional Flood Defences: Technical report

    NARCIS (Netherlands)

    Lendering, K.T.

    2015-01-01

    Historically the Netherlands have always had to deal with the threat of flooding, both from the rivers and the sea as well as from heavy rainfall. The country consists of a large amount of polders, which are low lying areas of land protected from flooding by embankments. These polders require an

  1. Flood Risk Regional Flood Defences: Technical report

    NARCIS (Netherlands)

    Lendering, K.T.

    2015-01-01

    Historically the Netherlands have always had to deal with the threat of flooding, both from the rivers and the sea as well as from heavy rainfall. The country consists of a large amount of polders, which are low lying areas of land protected from flooding by embankments. These polders require an ext

  2. Daily rainfall variability over northeastern Argentina in the La Plata River basin.

    Science.gov (United States)

    García, Norberto O; Pedraza, Raúl A

    2008-12-01

    We did a brief description of the climatic behavior and after this we analyzed the temporal variation in the total number of days a year with rainfall and the number of days a year with rainfall above the 100 mm threshold at the rain gauging stations in northeastern Argentina south of the La Plata River basin. The results show an increase both in the frequency of daily rainfall, especially during the winter season, and the frequency of days with heavy rainfall starting in the early 1970s. The increase in frequency of occurrence is more significant in the case of heavy rainfall. The annual maximum rainfall was calculated for periods of 1, 3, 5, 7, and 10 consecutive days at regional rain gauging stations for the respective historical periods, and the rain intensity-duration-return period curves (IDT) were determined on a frequency analysis. The IDT curves were compared with rainfall intensity-duration data of critical storms occurring in the last decades. We noticed that the rain intensities of critical storms (mostly convective) widely exceeded the intensities given by the 100-year IDT curves, particularly for short durations. The increase in both the frequency of heavy rainfall occurrence and rain intensity from the 1970s onward shows an increase in frequency and intensity of the meso-scale convective systems in the region resulting from climatic change. These systems tend to produce rainfall of very high intensity that is spatially concentrated and which generally produces significant floods in the local rivers.

  3. Uncertainty in flood risk mapping

    Science.gov (United States)

    Gonçalves, Luisa M. S.; Fonte, Cidália C.; Gomes, Ricardo

    2014-05-01

    , which indicates all possible peak flow values and the possibility of their occurrence. To produce the LCM a supervised soft classifier is used to perform the classification of a satellite image and a possibility distribution is assign to the pixels. These extra data provide additional land cover information at the pixel level and allow the assessment of the classification uncertainty, which is then considered in the identification of the parameters uncertainty used to compute peak flow. The proposed approach was applied to produce vulnerability and risk maps that integrate uncertainty in the urban area of Leiria, Portugal. A SPOT - 4 satellite image and DEMs of the region were used and the peak flow was computed using the Soil Conservation Service method. HEC-HMS, HEC-RAS, Matlab and ArcGIS software programs were used. The analysis of the results obtained for the presented case study enables the order of magnitude of uncertainty on the watershed peak flow value and the identification of the areas which are more susceptible to flood risk to be identified.

  4. Multilevel integrated flood management aproach

    Science.gov (United States)

    Brilly, Mitja; Rusjan, Simon

    2013-04-01

    The optimal solution for complex flood management is integrated approach. Word »integration« used very often when we try to put something together, but should distinguish full multiple integrated approach of integration by parts when we put together and analyse only two variables. In doing so, we lost complexity of the phenomenon. Otherwise if we try to put together all variables we should take so much effort and time and we never finish the job properly. Solution is in multiple integration captures the essential factors, which are different on a case-by-case (Brilly, 2000). Physical planning is one of most important activity in which flood management should be integrated. The physical planning is crucial for vulnerability and its future development and on other hand our structural measures must be incorporate in space and will very often dominated in. The best solution is if space development derived on same time with development of structural measures. There are good examples with such approach (Vienna, Belgrade, Zagreb, and Ljubljana). Problems stared when we try incorporating flood management in already urbanised area or we would like to decrease risk to some lower level. Looking to practice we learn that middle Ages practices were much better than to day. There is also »disaster by design« when hazard increased as consequence of upstream development or in stream construction or remediation. In such situation we have risk on areas well protected in the past. Good preparation is essential for integration otherwise we just lost time what is essential for decision making and development. We should develop clear picture about physical characteristics of phenomena and possible solutions. We should develop not only the flood maps; we should know how fast phenomena could develop, in hour, day or more. Do we need to analyse ground water - surface water relations, we would like to protected area that was later flooded by ground water. Do we need to take care about

  5. Physico-geographical characterization of the landscape denominated flood-prone lowlands. The case of the Protected Natural Reserve Balamkín, Campeche

    OpenAIRE

    Alvaro Gerardo Palacio Aponte; Rodolfo Noriega Trejo; Pedro Zamora Crecendo

    2012-01-01

    This paper describes landscape areas locally known as flood-prone lowlands, found in southeastern Campeche, Mexico. Functionally, these are not restricted to cumulative plains covered with flooded soils (gleysols) and waterborne vegetation ("palo de tinte"), as suggested in the past. This study demonstrates that these landscape areas are closely linked and correlated to geoforms and adjacent ecosystems. In order to support these correlations, all landscape components are described, and the im...

  6. Thyroid abnormality trend over time in northeastern regions of Kazakstan, adjacent to the Semipalatinsk nuclear test site. A case review of pathological findings for 7271 patients

    Energy Technology Data Exchange (ETDEWEB)

    Zhumadilov, Z. [Semipalatinsk State Medical Academy (Kazakstan); Gusev, B.I.; Takada, Jun; Hoshi, Masaharu; Kimura, Akiro; Hayakawa, Norihiko; Takeichi, Nobuo

    2000-03-01

    From 1949 through 1989 nuclear weapons testing carried out by the former Soviet Union at the Semipalatinsk Nuclear Test Site (SNTS) resulted in local fallout affecting the residents of Semipalatinsk, Ust-Kamenogorsk and Pavlodar regions of Kazakstan. To investigate the possible relationship between radiation exposure and thyroid gland abnormalities, we conducted a case review of pathological findings of 7271 urban and rural patients who underwent surgery from 1966-96. Of the 7271 patients, 761 (10.5%) were men, and 6510 (89.5%) were women. The age of the patients varied from 15 to 90 years. Overall, a diagnosis of adenomatous goiter (most frequently multinodular) was found in 1683 patients (63.4%) of Semipalatinsk region, in 2032 patients (68.6%) of Ust-Kamenogorsk region and in 1142 patients (69.0%) of Pavlodar region. In the period 1982-96, as compared before, there was a noticeable increase in the number of cases of Hashimoto's thyroiditis and thyroid cancer. Among histological forms of thyroid cancer, papillary (48.1%) and follicular (33.1%) predominated in the Semipalatinsk region. In later periods (1987-96), an increased frequency of abnormal cases occurred among patients less than 40 years of age, with the highest proportion among patients below 20 in Semipalatinsk and Ust-Kamenogorsk regions of Kazakstan. Given the positive findings of a significant cancer-period interaction, and a significant trend for the proportion of cancer to increase over time, we recommend more detailed and etiologic studies of thyroid disease among populations exposed to radiation fallout from the SNTS in comparison to non-exposed population. (author)

  7. Assessing coastal flooding hazard in urban areas: the case of estuarian villages in the city of Hyères-les-Palmiers

    Directory of Open Access Journals (Sweden)

    Le Roy Sylvestre

    2016-01-01

    Full Text Available This study, conducted on the city of Hyéres-les-Palmiers (French Riviera to guide the future land use planning, aimed to evaluate how sea level rise could modify coastal flooding hazards in urban areas located near small estuaries in a microtidal context. A joint probability approach allowed establishing typical storm parameters for specific return periods (30, 50 and 100 years, integrating offshore conditions (sea level and significant wave height and the river level. Storm scenarios have been established from these parameters and the chronology of the most impacting recent storm. Sea level rise has been integrated (20 cm for year 2030 and 60 cm for year 2100, and the coastal flooding has been simulated with a non-hydrostatic non-linear shallow-water model (SWASH. The calculations have been realized on high resolution DEM (1 to 5 m mesh size, integrating buildings and coastal protections. The approach has been validated by reproducing a recent flooding event. Obtained results show the importance of wave overtopping in current coastal flooding hazard in this area. Nevertheless, if Hyéres-les-Palmiers is currently little exposed to coastal flooding, these simulations highlight an increasing role of overflowing due to sea level rise, leading to significant flooding in 2100, even for quite frequent events.

  8. Assessing infrastructure vulnerability to major floods

    Energy Technology Data Exchange (ETDEWEB)

    Jenssen, Lars

    1998-12-31

    This thesis proposes a method for assessing the direct effects of serious floods on a physical infrastructure or utility. This method should be useful in contingency planning and in the design of structures likely to be damaged by flooding. A review is given of (1) methods of floodplain management and strategies for mitigating floods, (2) methods of risk analysis that will become increasingly important in flood management, (3) methods for hydraulic computations, (4) a variety of scour assessment methods and (5) applications of geographic information systems (GIS) to the analysis of flood vulnerability. Three computer codes were developed: CULVCAP computes the headwater level for circular and box culverts, SCOUR for assessing riprap stability and scour depths, and FASTFLOOD prepares input rainfall series and input files for the rainfall-runoff model used in the case study. A road system in central Norway was chosen to study how to analyse the flood vulnerability of an infrastructure. Finally, the thesis proposes a method for analysing the flood vulnerability of physical infrastructure. The method involves a general stage that will provide data on which parts of the infrastructure are potentially vulnerable to flooding and how to analyse them, and a specific stage which is concerned with analysing one particular kind of physical infrastructure in a study area. 123 refs., 59 figs., 17 tabs= .

  9. Flood avalanches in a semiarid basin with a dense reservoir network

    CERN Document Server

    Peter, Samuel J; Araújo, N A M; Herrmann, H J

    2014-01-01

    This study investigates flood avalanches in a dense reservoir network in the semiarid north-eastern Brazil. The population living in this area strongly depends on the availability of the water from this network. Water is stored during intense wet-season rainfall events and evaporates from the reservoir surface during the dry season. These seasonal changes are the driving forces behind the water dynamics in the network. The reservoir network and its connectivity properties during flood avalanches are investigated with a model called ResNetM, which simulates each reservoir explicitly. It runs on the basis of daily calculated water balances for each reservoir. A spilling reservoir contributes with water to the reservoir downstream, which can trigger avalanches affecting, in some cases, large fractions of the network. The main focus is on the study of the relation between the total amount of water stored and the largest observable cluster of connected reservoirs that overspill in the same day. It is shown that th...

  10. Climate, orography and scale controls on flood frequency in Triveneto (Italy)

    Science.gov (United States)

    Persiano, Simone; Castellarin, Attilio; Salinas, Jose Luis; Domeneghetti, Alessio; Brath, Armando

    2016-05-01

    The growing concern about the possible effects of climate change on flood frequency regime is leading Authorities to review previously proposed reference procedures for design-flood estimation, such as national flood frequency models. Our study focuses on Triveneto, a broad geographical region in North-eastern Italy. A reference procedure for design flood estimation in Triveneto is available from the Italian NCR research project "VA.PI.", which considered Triveneto as a single homogeneous region and developed a regional model using annual maximum series (AMS) of peak discharges that were collected up to the 1980s by the former Italian Hydrometeorological Service. We consider a very detailed AMS database that we recently compiled for 76 catchments located in Triveneto. All 76 study catchments are characterized in terms of several geomorphologic and climatic descriptors. The objective of our study is threefold: (1) to inspect climatic and scale controls on flood frequency regime; (2) to verify the possible presence of changes in flood frequency regime by looking at changes in time of regional L-moments of annual maximum floods; (3) to develop an updated reference procedure for design flood estimation in Triveneto by using a focused-pooling approach (i.e. Region of Influence, RoI). Our study leads to the following conclusions: (1) climatic and scale controls on flood frequency regime in Triveneto are similar to the controls that were recently found in Europe; (2) a single year characterized by extreme floods can have a remarkable influence on regional flood frequency models and analyses for detecting possible changes in flood frequency regime; (3) no significant change was detected in the flood frequency regime, yet an update of the existing reference procedure for design flood estimation is highly recommended and we propose the RoI approach for properly representing climate and scale controls on flood frequency in Triveneto, which cannot be regarded as a single

  11. How Can Flood Affect the Real Estate Market?

    Science.gov (United States)

    Trejo Rangel, Miguel Angel; Sapač, Klaudija; Brilly, Mitja

    2016-04-01

    The purpose of this paper is to examine how actual flood events can affect the real estate for different case studies. Therefore, we have analysed the impact for two cases, the first is the flood event which occurred in 2013 in Boulder, Colorado, United States, city that is located in the eastern part of the Rocky Mountains, and the second event was the flood which occurred in 2010 the city of Ljubljana, capital and largest city of Slovenia, that is located between the Alpine and Balkan mountains.. The methodology that was used is comparison of mean prices of real estate, taking into account the flood events which have been chosen in accordance with the available data and previous studies, furthermore for the case study of Ljubljana, Slovenia questionnaires were sent through one civil organization which is actively working in the area (Civil Initiative for Flood Security SW part of Ljubljana). Analysed sales prices during the period 2009-2014 in the case study of Boulder, Colorado, United States showed that the flood event in 2013 did not significantly affect the mean price of real estate within the flooded area, besides prices inside the flood plain tended to stay above the prices outside the floodplain. Nevertheless, we have found that the flood event affected the real estate sector in terms of number of sales, being that after the flood event in 2013 sales decreased 52% regarding the previous years. For the case study of Ljubljana, Slovenia the results were unexpected somehow. In fact we expected that the prices of real estate located within the flooded areas, on average, would be lower than those located outside the flooded areas, and that was what shown in the results, which is actually opposite to what occurred for the case study of Boulder City. However the research showed that the flood event in 2010 did not affect the change in prices of real estate within the flooded areas and the trend was considerable similar to previous years the flood event in 2010

  12. Engineering Strategies on Flood Control in Middle Reach of Yangtze River, China

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Flood disaster has been a serious hidden danger since the ancient time. The essential cause for the fact that floods have not been eliminated for hundreds of years is that time-honored strategies do not suit the cases of flood prevention. In the view of geological environmental analyses of flood formation and from the synthesis of experiences gained in flood control in the past hundreds of years, sluggish draining of flood, silt sedimentation in channel and building levee blindly constitute the main cause of intractable flood for a long time in the middle reach of the Yangtze River.Draining away silt and water is the only way to stamping out flood disaster. Opening up artificial waterways for flood diversion, draining away the silt of channel into the polders, and storing the flood water are important engineering measures for the flood control and damage reduction.

  13. Mechanisms of gas migration in flooding post-mining context

    Energy Technology Data Exchange (ETDEWEB)

    Le Gal, N.; Lagneau, V. [MINES ParisTech, Fontainebleau (France). Geosciences Center, Hydrodynamic and Reactions Unit; Charmoille, A. [INERIS, Verneuil-en-Halatte (France). Dept. of Ground and Underground Risks, Groundwater and Gas Emission Unit

    2010-07-01

    This paper described a study being conducted by the French National Institute for Industrial Environment and Risks (INERIS) and the European Flooding Management for Underground Coal Mines Considering Regional Mining Networks (FLOMINET) program to analyze gas migration during and after mine flooding. In situ flow measurements and laboratory studies were used to characterize gas transfer and the influence of hydrostatic pressure on coal methane releases. A sorption capacity under high hydrostatic pressure during rock flooding (CASPER) device was used to evaluate gas sorption and gas releases by reproducing depth conditions in a water-saturated context in an autoclave cell. Several models are currently also being developed to characterize mine methane migration. A reactive transport model was used to simulate methane sorption constants under high hydrostatic pressure. Mines in the Lorraine basin in northeastern France were considered. Results of the research study will be used to prevent hazards associated with surface gas emissions from abandoned mines. 10 refs., 3 figs.

  14. Adaptation to flood risk: Results of international paired flood event studies

    DEFF Research Database (Denmark)

    Kreibich, Heidi; Di Baldassarre, Giuliano; Vorogushyn, Sergiy

    2017-01-01

    As flood impacts are increasing in large parts of the world, understanding the primary drivers of changes in risk is essential for effective adaptation. To gain more knowledge on the basis of empirical case studies, we analyze eight paired floods, that is, consecutive flood events that occurred...... in the same region, with the second flood causing significantly lower damage. These success stories of risk reduction were selected across different socioeconomic and hydro-climatic contexts. The potential of societies to adapt is uncovered by describing triggered societal changes, as well as formal measures...... and spontaneous processes that reduced flood risk. This novel approach has the potential to build the basis for an international data collection and analysis effort to better understand and attribute changes in risk due to hydrological extremes in the framework of the IAHSs Panta Rhei initiative. Across all case...

  15. Flood Impact Modelling and Natural Flood Management

    Science.gov (United States)

    Owen, Gareth; Quinn, Paul; ODonnell, Greg

    2016-04-01

    Local implementation of Natural Flood Management methods are now being proposed in many flood schemes. In principal it offers a cost effective solution to a number of catchment based problem as NFM tackles both flood risk and WFD issues. However within larger catchments there is the issue of which subcatchments to target first and how much NFM to implement. If each catchment has its own configuration of subcatchment and rivers how can the issues of flood synchronisation and strategic investment be addressed? In this study we will show two key aspects to resolving these issues. Firstly, a multi-scale network water level recorder is placed throughout the system to capture the flow concentration and travel time operating in the catchment being studied. The second is a Flood Impact Model (FIM), which is a subcatchment based model that can generate runoff in any location using any hydrological model. The key aspect to the model is that it has a function to represent the impact of NFM in any subcatchment and the ability to route that flood wave to the outfall. This function allows a realistic representation of the synchronisation issues for that catchment. By running the model in interactive mode the user can define an appropriate scheme that minimises or removes the risk of synchornisation and gives confidence that the NFM investment is having a good level of impact downstream in large flood events.

  16. Urban pluvial flood prediction

    DEFF Research Database (Denmark)

    Thorndahl, Søren Liedtke; Nielsen, Jesper Ellerbæk; Jensen, David Getreuer

    2016-01-01

    Flooding produced by high-intensive local rainfall and drainage system capacity exceedance can have severe impacts in cities. In order to prepare cities for these types of flood events – especially in the future climate – it is valuable to be able to simulate these events numerically both...... historically and in real-time. There is a rather untested potential in real-time prediction of urban floods. In this paper radar data observations with different spatial and temporal resolution, radar nowcasts of 0–2 h lead time, and numerical weather models with lead times up to 24 h are used as inputs...... to an integrated flood and drainage systems model in order to investigate the relative difference between different inputs in predicting future floods. The system is tested on a small town Lystrup in Denmark, which has been flooded in 2012 and 2014. Results show it is possible to generate detailed flood maps...

  17. An Integrated Ensemble-Based Operational Framework to Predict Urban Flooding: A Case Study of Hurricane Sandy in the Passaic and Hackensack River Basins

    Science.gov (United States)

    Saleh, F.; Ramaswamy, V.; Georgas, N.; Blumberg, A. F.; Wang, Y.

    2016-12-01

    Advances in computational resources and modeling techniques are opening the path to effectively integrate existing complex models. In the context of flood prediction, recent extreme events have demonstrated the importance of integrating components of the hydrosystem to better represent the interactions amongst different physical processes and phenomena. As such, there is a pressing need to develop holistic and cross-disciplinary modeling frameworks that effectively integrate existing models and better represent the operative dynamics. This work presents a novel Hydrologic-Hydraulic-Hydrodynamic Ensemble (H3E) flood prediction framework that operationally integrates existing predictive models representing coastal (New York Harbor Observing and Prediction System, NYHOPS), hydrologic (US Army Corps of Engineers Hydrologic Modeling System, HEC-HMS) and hydraulic (2-dimensional River Analysis System, HEC-RAS) components. The state-of-the-art framework is forced with 125 ensemble meteorological inputs from numerical weather prediction models including the Global Ensemble Forecast System, the European Centre for Medium-Range Weather Forecasts (ECMWF), the Canadian Meteorological Centre (CMC), the Short Range Ensemble Forecast (SREF) and the North American Mesoscale Forecast System (NAM). The framework produces, within a 96-hour forecast horizon, on-the-fly Google Earth flood maps that provide critical information for decision makers and emergency preparedness managers. The utility of the framework was demonstrated by retrospectively forecasting an extreme flood event, hurricane Sandy in the Passaic and Hackensack watersheds (New Jersey, USA). Hurricane Sandy caused significant damage to a number of critical facilities in this area including the New Jersey Transit's main storage and maintenance facility. The results of this work demonstrate that ensemble based frameworks provide improved flood predictions and useful information about associated uncertainties, thus

  18. Assessment of static flood modeling techniques: application to contrasting marshes flooded during Xynthia (western France

    Directory of Open Access Journals (Sweden)

    J. F. Breilh

    2013-06-01

    Full Text Available This study aims to assess the performance of raster-based flood modeling methods on a wide diversity of coastal marshes. These methods are applied to the flooding associated with the storm Xynthia, which severely hit the western coast of France in February 2010. Static and semi-dynamic methods are assessed using a combination of LiDAR data, post-storm delineation of flooded areas and sea levels originating from both tide gauge measurements and storm surge modeling. Static methods are applied to 27 marshes showing a wide geomorphological diversity. It appears that these methods are suitable for marshes with a small distance between the coastline and the landward boundary of the marsh, which causes these marshes to flood rapidly. On the contrary, these methods overpredict flooded areas for large marshes where the distance between the coastline and the landward boundary of the marsh is large, because the flooding cannot be considered as instantaneous. In this case, semi-dynamic methods based on surge overflowing volume calculations can improve the flooding prediction significantly. This study suggests that static and semi-dynamic flood modeling methods can be attractive and quickly deployed to rapidly produce predictive flood maps of vulnerable areas under certain conditions, particularly for small distances between the coastline and the landward boundary of the low-lying coastal area.

  19. Flood risk awareness during the 2011 floods in the central United States: showcasing the importance of hydrologic data and interagency collaboration

    Science.gov (United States)

    Holmes, Jr., Robert R.; Schwein, Noreen O.; Shadie, Charles E.

    2012-01-01

    Floods have long had a major impact on society and the environment, evidenced by the more than 1,500 federal disaster declarations since 1952 that were associated with flooding. Calendar year 2011 was an epic year for floods in the United States, from the flooding on the Red River of the North in late spring to the Ohio, Mississippi, and Missouri River basin floods in the spring and summer to the flooding caused by Hurricane Irene along the eastern seaboard in August. As a society, we continually seek to reduce flood impacts, with these efforts loosely grouped into two categories: mitigation and risk awareness. Mitigation involves such activities as flood assessment, flood control implementation, and regulatory activities such as storm water and floodplain ordinances. Risk awareness ranges from issuance of flood forecasts and warnings to education of lay audiences about the uncertainties inherent in assessing flood probability and risk. This paper concentrates on the issue of flood risk awareness, specifically the importance of hydrologic data and good interagency communication in providing accurate and timely flood forecasts to maximize risk awareness. The 2011 floods in the central United States provide a case study of the importance of hydrologic data and the value of proper, timely, and organized communication and collaboration around the collection and dissemination of that hydrologic data in enhancing the effectiveness of flood forecasting and flood risk awareness.

  20. Probabilistic Flood Mapping using Volunteered Geographical Information

    Science.gov (United States)

    Rivera, S. J.; Girons Lopez, M.; Seibert, J.; Minsker, B. S.

    2016-12-01

    Flood extent maps are widely used by decision makers and first responders to provide critical information that prevents economic impacts and the loss of human lives. These maps are usually obtained from sensory data and/or hydrologic models, which often have limited coverage in space and time. Recent developments in social media and communication technology have created a wealth of near-real-time, user-generated content during flood events in many urban areas, such as flooded locations, pictures of flooding extent and height, etc. These data could improve decision-making and response operations as events unfold. However, the integration of these data sources has been limited due to the need for methods that can extract and translate the data into useful information for decision-making. This study presents an approach that uses volunteer geographic information (VGI) and non-traditional data sources (i.e., Twitter, Flicker, YouTube, and 911 and 311 calls) to generate/update the flood extent maps in areas where no models and/or gauge data are operational. The approach combines Web-crawling and computer vision techniques to gather information about the location, extent, and water height of the flood from unstructured textual data, images, and videos. These estimates are then used to provide an updated flood extent map for areas surrounding the geo-coordinate of the VGI through the application of a Hydro Growing Region Algorithm (HGRA). HGRA combines hydrologic and image segmentation concepts to estimate a probabilistic flooding extent along the corresponding creeks. Results obtained for a case study in Austin, TX (i.e., 2015 Memorial Day flood) were comparable to those obtained by a calibrated hydrologic model and had good spatial correlation with flooding extents estimated by the Federal Emergency Management Agency (FEMA).

  1. Application of Advection-Diffusion Routing Model to Flood Wave Propagation:A Case Study on Big Piney River, Missouri USA

    Institute of Scientific and Technical Information of China (English)

    Yang Yang; Theodore A Endreny; David J Nowak

    2016-01-01

    Flood wave propagation modeling is of critical importance to advancing water re-sources management and protecting human life and property. In this study, we investigated how the advection-diffusion routing model performed in flood wave propagation on a 16 km long down-stream section of the Big Piney River, MO. Model performance was based on gaging station data at the upstream and downstream cross sections. We demonstrated with advection-diffusion theory that for small differences in watershed drainage area between the two river cross sections, inflow along the reach mainly contributes to the downstream hydrograph’s rising limb and not to the falling limb. The downstream hydrograph’s falling limb is primarily determined by the propagated flood wave originating at the upstream cross section. This research suggests the parameter for the advection-diffusion routing model can be calibrated by fitting the hydrograph falling limb. Application of the advection diffusion model to the flood wave of January 29, 2013 supports our theoretical finding that the propagated flood wave determines the downstream cross section falling limb, and the model has good performance in our test examples.

  2. Assessment of the Impact of New Investments on Flood Hazard-Study Case: The Bridge on the Warta River near Wronki

    Directory of Open Access Journals (Sweden)

    Tomasz Dysarz

    2015-10-01

    Full Text Available The main concern of the study was the evaluation of the impact of new investment in road infrastructure on the flood hazard. The flood hazard is considered here on the basis of maps according to requirements of EU Flood Directive. The analyses presented were made for the Warta river, near the town of Wronki. The procedure included data collection and processing, model configuration, hydraulic simulation, generation of water surface profiles, and flood hazard maps. The ArcGIS tools, as well as HEC-RAS package, were used in this research. The model recalibration described in the paper provided excellent results according to independent criteria. Hence, the results obtained may be considered as valid. Finally the results reconstructing the conditions with and without the bridge are compared. The assessed impact of the bridge seems to be moderate, but the procedure proposed in the presented paper may be of wider application. In view of the EU Flood Directive and plans for investments in road infrastructure, the methodology presented seems very attractive.

  3. Holocene Environmental Magnetic Studies in northeastern Taiwan

    Science.gov (United States)

    Lee, T.; Yang, T.

    2010-12-01

    This study will present the environmental magnetic results analyzed from two lacustrine sediment cores raised from Ta-Hu Lake of Ilan County at northeastern Taiwan. The total recovered length of core DH-7A is of about 53.3 meters and that of the core DH-7B is of about 35.5 meters. Based on the C-14 dating, the former core could provide the information for the whole Holocene and the later one could support the data at least for the last 7,600 years. For those magnetic proxies representing the abundant variation of magnetic minerals, such as SIRM, bIRM, ARM, HIRM etc., show very spiky patterns. High abundant signals are usually accompanied by increasing of the fine grain signal (ARM/χ) and decreasing the S-ratio. Based on the difference between the magnetic results of the two cores and the analysis of organic matters of the core, these spikes might represent the flooding events brought the sediments from the outside drainage area into the lake due to severe heavy rainfalls in the area studied. In addition, based on the characteristic variation patterns of the used magnetic proxies several periods could be delimited. Higher sedimentation rate could be found at the two periods, 7600~5800 yrB.P. and 2000~500 yrB.P., which is of about 3-4 times of the others. Also their magnetic signals changed much frequent than the others. The results may related to the strengthen/weaken evolution of the East Asia monsoon.

  4. Indoor air quality in green buildings: A case-study in a residential high-rise building in the northeastern United States.

    Science.gov (United States)

    Xiong, Youyou; Krogmann, Uta; Mainelis, Gediminas; Rodenburg, Lisa A; Andrews, Clinton J

    2015-01-01

    Improved indoor air quality (IAQ) is one of the critical components of green building design. Green building tax credit (e.g., New York State Green Building Tax Credit (GBTC)) and certification programs (e.g., Leadership in Energy & Environmental Design (LEED)) require indoor air quality measures and compliance with allowable maximum concentrations of common indoor air pollutants. It is not yet entirely clear whether compliance with these programs results in improved IAQ and ultimately human health. As a case in point, annual indoor air quality measurements were conducted in a residential green high-rise building for five consecutive years by an industrial hygiene contractor to comply with the building's GBTC requirements. The implementation of green design measures resulted in better IAQ compared to data in references of conventional homes for some parameters, but could not be confirmed for others. Relative humidity and carbon dioxide were satisfactory according to existing standards. Formaldehyde levels during four out of five years were below the most recent proposed exposure limits found in the literature. To some degree, particulate matter (PM) levels were lower than that in studies from conventional residential buildings. Concentrations of Volatile Organic Compounds (VOCs) with known permissible exposure limits were below levels known to cause chronic health effects, but their concentrations were inconclusive regarding cancer health effects due to relatively high detection limits. Although measured indoor air parameters met all IAQ maximum allowable concentrations in GBTC and applicable LEED requirements at the time of sampling, we argue that these measurements were not sufficient to assess IAQ comprehensively because more sensitive sampling/analytical methods for PM and VOCs are needed; in addition, there is a need for a formal process to ensure rigor and adequacy of sampling and analysis methods. Also, we suggest that a comprehensive IAQ assessment should

  5. Surveys of water velocities in the vicinity of the discharge-release gates of Salamonie Lake Dam, northeastern Indiana, spring and winter 1998

    Science.gov (United States)

    Morlock, Scott E.; Stewart, James A.

    2000-01-01

    Two water-velocity surveys in the vicinity of the discharge-release gates were performed at the Salamonie Lake flood-control reservoir in northeastern Indiana during periods of high-discharge release. One survey was done in the spring when the reservoir pool was at high elevation; the other survey was in the winter when the reservoir pool was low.

  6. Predictability of prototype flash flood events in the Western Mediterranean under uncertainties of the precursor upper-level disturbance: the HYDROPTIMET case studies

    Directory of Open Access Journals (Sweden)

    R. Romero

    2005-01-01

    Full Text Available The HYDROPTIMET case studies (9–10 June 2000 Catalogne, 8–9 September 2002 Cévennes and 24–26 November 2002 Piémont appear to encompass a sort of prototype flash-flood situations in the western Mediterranean attending to the relevant synoptic and mesoscale signatures identified on the meteorological charts. In Catalogne, the convective event was driven by a low-pressure system of relatively small dimensions developed over the mediterranean coast of Spain that moved into southern France. For Cévennes, the main circulation pattern was a synoptic-scale Atlantic low which induced a persistent southerly low-level jet (LLJ over the western Mediterranean, strengthened by the Alps along its western flank, which guaranteed continuous moisture supply towards southern France where the long-lived, quasistationary convective system developed. The long Piémont episode, very representative of the most severe alpine flash flood events, shares some similarities with the Cévennes situation during its first stage in that it was controlled by a southerly moist LLJ associated with a large-scale disturbance located to the west. However, these circulation features were transient aspects and during the second half of the episode the situation was dominated by a cyclogenesis process over the Mediterranean which gave place to a mesoscale-size depression at surface that acted to force new heavy rain over the slopes of the Alps and maritime areas. That is, the Piémont episode can be catalogued as of mixed type with regard to the responsible surface disturbance, evolving from a large-scale pattern with remote action (like Cévennes to a mesoscale pattern with local action (like Catalogne. A prominent mid-tropospheric trough or cut-off low can be identified in all events prior and during the period of heavy rain, which clearly served as the precursor agent for the onset of the flash-flood conditions and the cyclogenesis at low-levels. Being aware of the

  7. Uncertainty in surface water flood risk modelling

    Science.gov (United States)

    Butler, J. B.; Martin, D. N.; Roberts, E.; Domuah, R.

    2009-04-01

    Two thirds of the flooding that occurred in the UK during summer 2007 was as a result of surface water (otherwise known as ‘pluvial') rather than river or coastal flooding. In response, the Environment Agency and Interim Pitt Reviews have highlighted the need for surface water risk mapping and warning tools to identify, and prepare for, flooding induced by heavy rainfall events. This need is compounded by the likely increase in rainfall intensities due to climate change. The Association of British Insurers has called for the Environment Agency to commission nationwide flood risk maps showing the relative risk of flooding from all sources. At the wider European scale, the recently-published EC Directive on the assessment and management of flood risks will require Member States to evaluate, map and model flood risk from a variety of sources. As such, there is now a clear and immediate requirement for the development of techniques for assessing and managing surface water flood risk across large areas. This paper describes an approach for integrating rainfall, drainage network and high-resolution topographic data using Flowroute™, a high-resolution flood mapping and modelling platform, to produce deterministic surface water flood risk maps. Information is provided from UK case studies to enable assessment and validation of modelled results using historical flood information and insurance claims data. Flowroute was co-developed with flood scientists at Cambridge University specifically to simulate river dynamics and floodplain inundation in complex, congested urban areas in a highly computationally efficient manner. It utilises high-resolution topographic information to route flows around individual buildings so as to enable the prediction of flood depths, extents, durations and velocities. As such, the model forms an ideal platform for the development of surface water flood risk modelling and mapping capabilities. The 2-dimensional component of Flowroute employs

  8. Exploring the co-production of digital storytelling for lay knowledge exchange within and between flood risk communities: the case of the River Severn, UK

    Directory of Open Access Journals (Sweden)

    Holmes Andrew

    2016-01-01

    Full Text Available This paper evaluates the potential role of co-produced digital storytelling as a medium of linking flood memories and lay knowledge exchange around flood preparedness for resilience within flood risk communities. The objectives of the described action focus on both process andd output - to capture memory of flood events, and to share critical reflection on, and adaptive learning from, flood experiences within and between communities. Very specific pieces of resilience stories on preparedness were co-produced into digital stories (audio and images working with individuals and small clusters of people. In the development process, stories were shared within the communities who created them, and within new communities. At all community events, the experience of sharing the stories was observed and evaluated using participant and facilitator questionnaires and independent observation. When shared in community events, the value of the digital media, nature of the story construction, the local or transferable nature of messages, and emotional weight given to the story were all appraised. The stories stimulated new discussions within different community groups and in multi-stakeholder meetings; conversations generated by the same digital story were found to differ depending on the setting. Listeners had high degrees of empathy with the stories gaining insights around “mobilising community#x201D; and “developing emotional resilience”. The paper explores issues of engagement in order to produce a participatory media -demonstrating the process and tensions of exchanging knowledge, and how the cultural practice of digital storytelling can jump the divide to policymaking and function as a successful way of engaging a wider public at flood risk.

  9. A multi-disciplinary approach to evaluate vulnerability and risks of pluvial floods under changing climate: the case study of the municipality of Venice (Italy).

    Science.gov (United States)

    Sperotto, Anna; Torresan, Silvia; Gallina, Valentina; Coppola, Erika; Critto, Andrea; Marcomini, Antonio

    2015-04-01

    Global climate change is expected to affect the intensity and frequency of extreme events (e.g. heat waves, drought, heavy precipitations events) leading to increasing natural disasters and damaging events (e.g. storms, pluvial floods and coastal flooding) worldwide. Especially in urban areas, disasters risks can be exacerbated by changes in exposure and vulnerability patterns (i.e. urbanization, population growth) and should be addressed by adopting a multi-disciplinary approach. A Regional Risk Assessment (RRA) methodology integrating climate and environmental sciences with bottom-up participative processes was developed and applied to the urban territory of the municipality of Venice in order to evaluate the potential consequences of climate change on pluvial flood risk in urban areas. Based on the consecutive analysis of hazard, exposure, vulnerability and risks, the RRA methodology is a screening risk tool to identify and prioritize major elements at risk (e.g. residential, commercial areas and infrastructures) and to localize sub-areas that are more likely to be affected by flood risk due to heavy precipitation events, in the future scenario (2041-2050). From the early stages of its development and application, the RRA followed a bottom-up approach to select and score site-specific vulnerability factors (e.g. slope, permeability of the soil, past flooded areas) and to consider the requests and perspectives of local stakeholders of the North Adriatic region, by means of interactive workshops, surveys and discussions. The main outputs of the assessment are risk and vulnerability maps and statistics aimed at increasing awareness about the potential effect of climate change on pluvial flood risks and at identifying hot-spot areas where future adaptation actions should be required to decrease physical-environmental vulnerabilities or building resilience and coping capacity of human society to climate change. The overall risk assessment methodology and the results

  10. A surface water flooding impact library for flood risk assessment

    Directory of Open Access Journals (Sweden)

    Aldridge Timothy

    2016-01-01

    Full Text Available The growing demand for improved risk-based Surface Water Flooding (SWF warning systems is evident in EU directives and in the UK Government’s Pitt Review of the 2007 summer floods. This paper presents a novel approach for collating receptor and vulnerability datasets via the concept of an Impact Library, developed by the Health and Safety Laboratory as a depository of pre-calculated impact information on SWF risk for use in a real-time SWF Hazard Impact Model (HIM. This has potential benefits for the Flood Forecasting Centre (FFC as the organisation responsible for the issuing of flood guidance information for England and Wales. The SWF HIM takes a pixel-based approach to link probabilistic surface water runoff forecasts produced by CEH’s Grid-to-Grid hydrological model with Impact Library information to generate impact assessments. These are combined to estimate flood risk as a combination of impact severity and forecast likelihood, at 1km pixel level, and summarised for counties and local authorities. The SWF HIM takes advantage of recent advances in operational ensemble forecasting of rainfall by the Met Office and of SWF by the Environment Agency and CEH working together through the FFC. Results are presented for a case study event which affected the North East of England during 2012. The work has been developed through the UK’s Natural Hazards Partnership (NHP, a group of organisations gathered to provide information, research and analysis on natural hazards for civil contingencies, government and responders across the UK.

  11. Modeling on Flash Flood Disaster Induced by Bed Load

    Institute of Scientific and Technical Information of China (English)

    CAO Shuyou; LIU Xingnian; HUANG Er; YANG Keiun

    2008-01-01

    Flash floods result from a complex interaction among hydro-meteorological, hydrologi-cal, and hydraulic processes across various spatial and temporal scales. Sichuan Province suffers flash floods frequently owing to mountain weather and topography. A flash flood and gravel bed load transport are two key relative problems in mountain river engineering. Bed materials are often encountered in alternate scouring and deposition in mountain fluvial processes during a flash flood.In this circumstance, CRS-1 bed load numerical model jointly with scale physical model is em-ployed to predict water level and gravel bed scour and deposition for design of flood control dykes and flash flood disaster mitigation. A case study on the mechanism of a flash flood disaster in-duced by bed load transport for a hydropower station in Sichuan Province is conducted. Finally,suggestions to protect the hydropower station are proposed.

  12. 77 FR 76499 - Changes in Flood Hazard Determinations

    Science.gov (United States)

    2012-12-28

    ... Flood Insurance Rate Maps (FIRMs), and in some cases the Flood Insurance Study (FIS) reports, currently... officer Community map Community State and county Location and case No. of community repository Effective... Honorable Gay Laramie County September 27, 2012 560029 1268). of Laramie County Woodhouse,...

  13. Visualization of the Impact of the Catastrophic Flooding Events

    DEFF Research Database (Denmark)

    Mioc, Darka; Anton, François; Moreri, K. K.

    maps. This can greatly help decision makers with the emergency measures and mitigation in most of the cases. In this article, we present a case study about mapping of flood risks due to a dam burst showing risk maps of flood hazards and available emergency facilities and their significance for risk...

  14. Primary healthcare system capacities for responding to storm and flood-related health problems: a case study from a rural district in central Vietnam

    Directory of Open Access Journals (Sweden)

    Hoang Van Minh

    2014-12-01

    Full Text Available Background: As a tropical depression in the East Sea, Vietnam is greatly affected by climate change and natural disasters. Knowledge of the current capacity of the primary healthcare system in Vietnam to respond to health issues associated with storms and floods is very important for policy making in the country. However, there has been little scientific research in this area. Objective: This research was to assess primary healthcare system capacities in a rural district in central Vietnam to respond to such health issues. Design: This was a cross-sectional descriptive study using quantitative and qualitative approaches. Quantitative methods used self-administered questionnaires. Qualitative methods (in-depth interviews and focus groups discussions were used to broaden understanding of the quantitative material and to get additional information on actions taken. Results: 1 Service delivery: Medical emergency services, especially surgical operations and referral systems, were not always available during the storm and flood seasons. 2 Governance: District emergency plans focus largely on disaster response rather than prevention. The plans did not clearly define the role of primary healthcare and had no clear information on the coordination mechanism among different sectors and organizations. 3 Financing: The budget for prevention and control of flood and storm activities was limited and had no specific items for healthcare activities. Only a little additional funding was available, but the procedures to get this funding were usually time-consuming. 4 Human resources: Medical rescue teams were established, but there were no epidemiologists or environmental health specialists to take care of epidemiological issues. Training on prevention and control of climate change and disaster-related health issues did not meet actual needs. 5 Information and research: Data that can be used for planning and management (including population and epidemiological

  15. Physico-geographical characterization of the landscape denominated flood-prone lowlands. The case of the Protected Natural Reserve Balamkín, Campeche

    Directory of Open Access Journals (Sweden)

    Alvaro Gerardo Palacio Aponte

    2012-03-01

    Full Text Available This paper describes landscape areas locally known as flood-prone lowlands, found in southeastern Campeche, Mexico. Functionally, these are not restricted to cumulative plains covered with flooded soils (gleysols and waterborne vegetation ("palo de tinte", as suggested in the past. This study demonstrates that these landscape areas are closely linked and correlated to geoforms and adjacent ecosystems. In order to support these correlations, all landscape components are described, and the importance and ecological role of vegetation as a biological indicator of the system's dynamics are highlighted.

  16. Primary healthcare system capacities for responding to storm and flood-related health problems: a case study from a rural district in central Vietnam.

    Science.gov (United States)

    Van Minh, Hoang; Tuan Anh, Tran; Rocklöv, Joacim; Bao Giang, Kim; Trang, Le Quynh; Sahlen, Klas-Göran; Nilsson, Maria; Weinehall, Lars

    2014-01-01

    As a tropical depression in the East Sea, Vietnam is greatly affected by climate change and natural disasters. Knowledge of the current capacity of the primary healthcare system in Vietnam to respond to health issues associated with storms and floods is very important for policy making in the country. However, there has been little scientific research in this area. This research was to assess primary healthcare system capacities in a rural district in central Vietnam to respond to such health issues. This was a cross-sectional descriptive study using quantitative and qualitative approaches. Quantitative methods used self-administered questionnaires. Qualitative methods (in-depth interviews and focus groups discussions) were used to broaden understanding of the quantitative material and to get additional information on actions taken. 1) Service delivery: Medical emergency services, especially surgical operations and referral systems, were not always available during the storm and flood seasons. 2) Governance: District emergency plans focus largely on disaster response rather than prevention. The plans did not clearly define the role of primary healthcare and had no clear information on the coordination mechanism among different sectors and organizations. 3) Financing: The budget for prevention and control of flood and storm activities was limited and had no specific items for healthcare activities. Only a little additional funding was available, but the procedures to get this funding were usually time-consuming. 4) Human resources: Medical rescue teams were established, but there were no epidemiologists or environmental health specialists to take care of epidemiological issues. Training on prevention and control of climate change and disaster-related health issues did not meet actual needs. 5) Information and research: Data that can be used for planning and management (including population and epidemiological data) were largely lacking. The district lacked a disease

  17. Flood Hazard Prediction from Soil Properties by Remote Sensing and Geographic Information System: A Case Study of Mae Rim Watershed,Chiang Mai Province,Thailand

    Institute of Scientific and Technical Information of China (English)

    PANJIANJIUN; E.BERGSMA; 等

    1998-01-01

    Physiography and soil in Mae Rim watershed,Chiang Mai Province,Thailand were investigated by using aerial photographs and satellite image in conjunction with field work,and soil infiltration rate and soil shear resistance were measured in field. Many factors affecting runoff were analyzed usig the Integrated Land and Water Informaiton System(ILWIS).As a result,a model determining flood hazar was set up.Three mps including runoff curve number map,runoff coefficent map,and flood inumdation map were created,In addition,the time of concentration was predicted.

  18. Interpreting the impact of flood forecasts by combining policy analysis studies and flood defence

    Directory of Open Access Journals (Sweden)

    Slomp Robert

    2016-01-01

    Full Text Available Flood forecasting is necessary to save lives and reduce damages. Reducing damages is important to save livelihoods and to reduce the recovery time. Flood alerts should contain expected time of the event, location and extent of the event. A flood alert is not only one message but part of a rehearsed flow of information using multiple canals. First people have to accept the fact that there might be a threat and what the threat is about. People need a reference to understand the situation and be aware of possible measures they can take to assure their own safety and reduce damages. Information to the general public has to be consistent with the information used by emergency services and has to be very clear about consequences and context of possible measures (as shelter in place or preventive evacuation. Emergency services should monitor how the public is responding to adapt their communication en operation during a crisis. Flood warnings and emergency services are often coordinated by different government organisations. This is an extra handicap for having consistent information out on time for people to use. In an information based society, where everyone has twitter, email and a camera, public organisations may have to trust the public more and send out the correct information as it comes in. In the Netherlands Rijkswaterstaat, the National Water Authority and the National Public Works Department, is responsible for or involved in forecasting in case of floods, policy studies on flood risk, policy studies on maintenance, assessment and design of flood defences, elaborating rules and regulations for flood defences, advice on crisis management to the national government and for maintaining the main infrastructure in the Netherlands (high ways and water ways. The Water Management Center in the Netherlands (WMCN has developed a number of models to provide flood forecasts. WMCN is run for and by all managers of flood defences and is hosted by

  19. Case Studies of the ROZ CO2 Flood and the Combined ROZ/MPZ CO2 Flood at the Goldsmith Landreth Unit, Ector County, Texas. Using ''Next Generation'' CO2 EOR Technologies to Optimize the Residual Oil Zone CO2 Flood

    Energy Technology Data Exchange (ETDEWEB)

    Trentham, Robert C. [Univ. of Texas, Midland, TX (United States); Melzer, L. Stephen [Univ. of Texas, Midland, TX (United States); Kuuskraa, Vello [Advanced Resources International, Inc., Arlington, VA (United States); Koperna, George [Advanced Resources International, Inc., Arlington, VA (United States)

    2015-06-30

    The technology for CO2 Enhanced Oil Recovery (CO2 EOR) has significantly advanced since the earliest floods were implemented in the 1970s. At least for the Permian Basin region of the U.S., the oil recovery has been now been extended into residual oil zones (ROZs) where the mobile fluid phase is water and immobile phase is oil. But the nature of the formation and fluids within the ROZs has brought some challenges that were not present when flooding the MPZs. The Goldsmith-Landreth project in the Permian Basin was intended to first identify the most pressing issues of the ROZs floods and, secondly, begin to address them with new techniques designed to optimize a flood that commingled the MPZ and the ROZ. The early phase of the research conducted considerable reservoir and fluid characterization work and identified both technical and commercial challenges of producing the enormous quantities of water when flooding the ROZs. It also noted the differing water compositions in the ROZ as compared to the overlying MPZs. A new CO2 gas lift system using a capillary string was successfully applied during the project which conveyed the CO2 to the deeper and differing ROZ reservoir conditions at Goldsmith and added a second capillary string that facilitated applying scale inhibitors to mitigate the scaling tendencies of the mixing ROZ and MPZ formation waters. The project also undertook a reservoir modeling effort, using the acquired reservoir characterization data, to history match both the primary and water flood phases of the MPZ and to establish the initial conditions for a modeling effort to forecast response of the ROZ to CO2 EOR. With the advantage of many profile logs acquired from the operator, some concentration on the original pattern area for the ROZ pilot was accomplished to attempt to perfect the history match for that area. Several optional scenarios for producing the ROZ were simulated seeking to find the

  20. A GIS based approach for the prediction of the dam break flood hazard – A case study of Zardezas reservoir “Skikda, Algeria”

    Directory of Open Access Journals (Sweden)

    Derdous Oussama

    2015-12-01

    Full Text Available The construction of dams in rivers can offer many advantages, however the consequences resulting from their failure could result in major damage, including loss of life and property destruction. To mitigate the threats of dam break it is essential to appreciate the characteristics of the potential flood in realistic manner. In this study an approach based on the integration of hydraulic modelling and GIS has been used to assess the risks resulting from a potential failure of Zardezas dam, a concrete dam located in Skikda, in the North East of Algeria. HEC-GeoRAS within GIS was used to extract geometric information from a digital elevation model and then imported into HEC-RAS. Flow simulation of the dam break was performed using HEC-RAS and results were mapped using the GIS. Finally, a flood hazard map based on water depth and flow velocity maps was created in GIS environment. According to this map the potential failure of Zardezas dam will place a large number in people in danger. The present study has shown that Application of Geographical Information System (GIS techniques in integration with hydraulic modelling can significantly reduce the time and the resources required to forecast potential dam break flood hazard which can play a crucial role in improving both flood disaster management and land use planning downstream of dams.

  1. Flash floods and debris flow in the city area of Messina, north-east part of Sicily, Italy in October 2009: the case of the Giampilieri catchment

    Directory of Open Access Journals (Sweden)

    G. T. Aronica

    2012-05-01

    Full Text Available This paper concerns the analysis of the 1 October 2009 flash flood and debris flow event caused by a very intense rainfall concentrated over the Messina area. The storm caused severe flash floods in many villages around the city of Messina, such as Giampilieri, Scaletta Zanclea, Altolia Superiore and Molino, with 38 casualties and significant damages to property, buildings, roads and bridges estimated close to 550 million Euro. The main focus of this work is to perform a post event analysis, putting together available meteorological and hydrological data in order to get better insight into temporal and spatial variability of the rain storm, the soil moisture conditions and the consequent flash flood in the Giampilieri catchment. The event was investigated using observed data from a raingauge network. Statistical analysis using GEV distribution was performed and rainfall return period (storm severity was estimated. Further, measured rainfall data and rainfall-runoff modelling were used to estimate soil moisture conditions, to analyse the hydrological behaviour and to reconstruct flood hydrograph. With the help of GIS technology and particularly spatial analysis, the volume of debris which has gone down into the Giampilieri village was also calculated. GIS maps with landslide and material deposit areas were produced and analysed.

  2. Social vulnerability assessment of flood risk using GIS-based multicriteria decision analysis. A case study of Vila Nova de Gaia (Portugal

    Directory of Open Access Journals (Sweden)

    Paulo Fernandez

    2016-07-01

    Full Text Available Over the last decade, flood disasters have affected millions of people and caused massive economic losses. Social vulnerability assessment uses a combination of several factors to represent a population's differential access to resources and its ability to cope with and respond to hazards. In this paper, social vulnerability assessment to flood risk was applied to the third most populous Portuguese municipality. The study was developed at the neighbourhood level, allowing for social vulnerability analysis at inter civil parish, intra civil parish, and municipality scales. A geographic information system-based multicriteria decision analysis (GIS-MCDA was applied to social vulnerability and allows for an increased understanding and improved monitoring of social vulnerability over space, identifying ‘hot spots’ that require adaptation policies. Mafamude, Oliveira do Douro, Vila Nova de Gaia, and Avintes civil parishes display the greatest vulnerability to flooding. According to the most pessimistic scenario 57%–68% of the area of these civil parishes is classed at a high or very high level of social vulnerability. The GIS-MCDA helps to assess what and who is at risk, and where targeted impact-reduction strategies should be implemented. The results demonstrate the importance of an urban-scale approach instead of a river basin scale to urban flood risk management plans.

  3. Increased Rotavirus Prevalence in Diarrheal Outbreak Precipitated by Localized Flooding, Solomon Islands, 2014.

    Science.gov (United States)

    Jones, Forrest K; Ko, Albert I; Becha, Chris; Joshua, Cynthia; Musto, Jennie; Thomas, Sarah; Ronsse, Axelle; Kirkwood, Carl D; Sio, Alison; Aumua, Audrey; Nilles, Eric J

    2016-05-01

    Flooding on 1 of the Solomon Islands precipitated a nationwide epidemic of diarrhea that spread to regions unaffected by flooding and caused >6,000 cases and 27 deaths. Rotavirus was identified in 38% of case-patients tested in the city with the most flooding. Outbreak potential related to weather reinforces the need for global rotavirus vaccination.

  4. Low-cost, open access flood inundation modelling with sparse data: A case study of the Lower Damodar River Basin, India

    Science.gov (United States)

    Sanyal, J.; Carbonneau, P.

    2012-04-01

    In developed nations, flood monitoring and management benefits from a range of high-cost modern data and methods such as high resolution terrain data and digital elevation models, cloud penetrating radar data which defines flood extents and advanced computer modelling software. However, in developing countries, such resources are rarely available. The situation is further compounded by the fact that developing countries often have higher population densities which are even more vulnerable to flood hazards. This paper addresses these issues and presents a methodology for flood modelling which is accessible within the resource constraints which are typical in developing countries. A 20 Km flood prone reach of the lower Damodar River Basin in Northern India has been selected as the study area. This area has been subjected to inundation 4 times during the last 6 years due to water released from a network of upstream reservoirs during intense monsoon rainfall events. Within the study site, topographic data from three sources was available. First, we used SRTM data. Second, 40 cross-sections were surveyed with differential GPS and a handheld depth sounder. These data were corrected and their datum adjusted to that of the SRTM DEM with the precise point positioning (PPP) system freely available from Natural Resources Canada. Third, low-cost Cartosat-1 stereo images were used to produce a DEM with Leica Photogrammetry Suite. The elevation points derived from Cartosat-1 images were then manually edited in a 3D stereo viewing environment to represent the narrow but hydraulically significant features, such as the embankments, roads, smaller depressions and merged with the surveyed points for the channel. The SRTM data over the featureless farmland was also made bare-earth and merged with the rest of the mass points to create a hybrid point cloud. The RMSE of this hybrid terrain data was found to be 1.1 m as compared to 2.4 m for the original SRTM DEM. TELEMAC2D, an open

  5. A multi-disciplinary approach to evaluate pluvial floods risk under changing climate: The case study of the municipality of Venice (Italy).

    Science.gov (United States)

    Sperotto, A; Torresan, S; Gallina, V; Coppola, E; Critto, A; Marcomini, A

    2016-08-15

    Global climate change is likely to pose increasing threats in nearly all sectors and across all sub-regions worldwide (IPCC, 2014). Particularly, extreme weather events (e.g. heavy precipitations), together with changing exposure and vulnerability patterns, are expected to increase the damaging effect of storms, pluvial floods and coastal flooding. Developing climate and adaptation services for local planners and decision makers is becoming essential to transfer and communicate sound scientific knowledge about climate related risks and foster the development of national, regional and local adaptation strategies. In order to analyze the effect of climate change on pluvial flood risk and advice adaptation planning, a Regional Risk Assessment (RRA) methodology was developed and applied to the urban territory of the municipality of Venice. Based on the integrated analysis of hazard, exposure, vulnerability and risk, RRA allows identifying and prioritizing targets and sub-areas that are more likely to be affected by pluvial flood risk due to heavy precipitation events in the future scenario 2041-2050. From the early stages of its development and application, the RRA followed a bottom-up approach taking into account the requests, knowledge and perspectives of local stakeholders of the North Adriatic region by means of interactive workshops, surveys and discussions. Results of the analysis showed that all targets (i.e. residential, commercial-industrial areas and infrastructures) are vulnerable to pluvial floods due to the high impermeability and low slope of the topography. The spatial pattern of risk mostly reflects the distribution of the hazard and the districts with the higher percentage of receptors' surface in the higher risk classes (i.e. very high, high and medium) are Lido-Pellestrina and Marghera. The paper discusses how risk-based maps and statistics integrate scientific and local knowledge with the final aim to mainstream climate adaptation in the development

  6. Potential of semi-structural and non-structural adaptation strategies to reduce future flood risk: case study for the Meuse

    Directory of Open Access Journals (Sweden)

    J. K. Poussin

    2012-11-01

    Full Text Available Flood risk throughout Europe has increased in the last few decades, and is projected to increase further owing to continued development in flood-prone areas and climate change. In recent years, studies have shown that adequate undertaking of semi-structural and non-structural measures can considerably decrease the costs of floods for households. However, there is little insight into how such measures can decrease the risk beyond the local level, now and in the future. To gain such insights, a modelling framework using the Damagescanner model with land-use and inundation maps for 2000 and 2030 was developed and applied to the Meuse river basin, in the region of Limburg, in the southeast of the Netherlands. The research suggests that annual flood risk may increase by up to 185% by 2030 compared with 2000, as a result of combined land-use and climate changes. The independent contributions of climate change and land-use change to the simulated increase are 108% and 37%, respectively. The risk-reduction capacity of the implementation of spatial zoning measures, which are meant to limit and regulate developments in flood-prone areas, is between 25% and 45%. Mitigation factors applied to assess the potential impact of three mitigation strategies (dry-proofing, wet-proofing, and the combination of dry- and wet-proofing in residential areas show that these strategies have a risk-reduction capacity of between 21% and 40%, depending on their rate of implementation. Combining spatial zoning and mitigation measures could reduce the total increase in risk by up to 60%. Policy implications of these results are discussed. They focus on the undertaking of effective mitigation measures, and possible ways to increase their implementation by households.

  7. Historical floods in the Dutch Rhine Delta

    Directory of Open Access Journals (Sweden)

    R. Glaser

    2003-01-01

    Full Text Available Historical records provide direct information about the climatic impact on society. Especially great natural disasters such as river floods have been for long attracting the attention of humankind. Time series for flood development on the Rhine branches Waal, Nederrijn/Lek and IJssel in the Dutch Rhine Delta are presented in this paper. In the case of the Waal it is even possible to compare historical flood frequencies based on documentary data with the recent development reconstructed from standardized instrumental measurements. In brief, we will also discuss various parameters concerning the structure of the flood series and the "human dimension" of natural disaster, i.e. the vulnerability of society when facing natural disasters.

  8. NASA Global Flood Mapping System

    Science.gov (United States)

    Policelli, Fritz; Slayback, Dan; Brakenridge, Bob; Nigro, Joe; Hubbard, Alfred

    2017-01-01

    Product utility key factors: Near real time, automated production; Flood spatial extent Cloudiness Pixel resolution: 250m; Flood temporal extent; Flash floods short duration on ground?; Landcover--Water under vegetation cover vs open water

  9. Floods Risk Management in Colombia

    Directory of Open Access Journals (Sweden)

    Leonardo Güiza Suárez

    2013-10-01

    Full Text Available The last rainy season 2010-2011 resulted in Colombia in around 500 casualties and more than 3.6 million of victims. Although this rainfall term accounted for one of the strongest it was not an unprecedented event since for more than fifty years this phenomenon has been taking place in the same Colombian regions producing casualties and victims. This fact makes us to think about the public management by authorities regarding flooding prevention in our country. This article elaborates on this topic explaining the risk management system in case of flooding in Colombia. It shows some national figures of the main ravages brought about by the 2010 2011 rainy seasons. Finally the article analyzes two cases of study of how operational is this public policy in risk management: La Mojana and Canal del Dique regions. It was evident that the state failed in managing the risk management from flooding because despite the important investment, every year the victims, casualties and material damages are increasing steadily.

  10. On Flood Alert

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    lina braces fora particularly dangerous flood season in the wake of disastrous rainstorms Aseries of heavy storms since early May led to severe flooding and landslides in south and southwest China,causing heavy casualties and economic losses. Severe convective weather such as downpours,

  11. Discover Floods Educators Guide

    Science.gov (United States)

    Project WET Foundation, 2009

    2009-01-01

    Now available as a Download! This valuable resource helps educators teach students about both the risks and benefits of flooding through a series of engaging, hands-on activities. Acknowledging the different roles that floods play in both natural and urban communities, the book helps young people gain a global understanding of this common--and…

  12. Ecology and Geography of Plague Transmission Areas in Northeastern Brazil

    Science.gov (United States)

    Giles, John; Peterson, A. Townsend; Almeida, Alzira

    2011-01-01

    Plague in Brazil is poorly known and now rarely seen, so studies of its ecology are difficult. We used ecological niche models of historical (1966-present) records of human plague cases across northeastern Brazil to assess hypotheses regarding environmental correlates of plague occurrences across the region. Results indicate that the apparently focal distribution of plague in northeastern Brazil is indeed discontinuous, and that the causes of the discontinuity are not necessarily only related to elevation—rather, a diversity of environmental dimensions correlate to presence of plague foci in the region. Perhaps most interesting is that suitable areas for plague show marked seasonal variation in photosynthetic mass, with peaks in April and May, suggesting links to particular land cover types. Next steps in this line of research will require more detailed and specific examination of reservoir ecology and natural history. PMID:21245925

  13. Sensitivity of Coastal Flood Risk Assessments to Digital Elevation Models

    Directory of Open Access Journals (Sweden)

    Bas van de Sande

    2012-07-01

    Full Text Available Most coastal flood risk studies make use of a Digital Elevation Model (DEM in addition to a projected flood water level in order to estimate the flood inundation and associated damages to property and livelihoods. The resolution and accuracy of a DEM are critical in a flood risk assessment, as land elevation largely determines whether a location will be flooded or will remain dry during a flood event. Especially in low lying deltaic areas, the land elevation variation is usually in the order of only a few decimeters, and an offset of various decimeters in the elevation data has a significant impact on the accuracy of the risk assessment. Publicly available DEMs are often used in studies for coastal flood risk assessments. The accuracy of these datasets is relatively low, in the order of meters, and is especially low in comparison to the level of accuracy required for a flood risk assessment in a deltaic area. For a coastal zone area in Nigeria (Lagos State an accurate LiDAR DEM dataset was adopted as ground truth concerning terrain elevation. In the case study, the LiDAR DEM was compared to various publicly available DEMs. The coastal flood risk assessment using various publicly available DEMs was compared to a flood risk assessment using LiDAR DEMs. It can be concluded that the publicly available DEMs do not meet the accuracy requirement of coastal flood risk assessments, especially in coastal and deltaic areas. For this particular case study, the publically available DEMs highly overestimated the land elevation Z-values and thereby underestimated the coastal flood risk for the Lagos State area. The findings are of interest when selecting data sets for coastal flood risk assessments in low-lying deltaic areas.

  14. A method for mapping flood hazard along roads.

    Science.gov (United States)

    Kalantari, Zahra; Nickman, Alireza; Lyon, Steve W; Olofsson, Bo; Folkeson, Lennart

    2014-01-15

    A method was developed for estimating and mapping flood hazard probability along roads using road and catchment characteristics as physical catchment descriptors (PCDs). The method uses a Geographic Information System (GIS) to derive candidate PCDs and then identifies those PCDs that significantly predict road flooding using a statistical modelling approach. The method thus allows flood hazards to be estimated and also provides insights into the relative roles of landscape characteristics in determining road-related flood hazards. The method was applied to an area in western Sweden where severe road flooding had occurred during an intense rain event as a case study to demonstrate its utility. The results suggest that for this case study area three categories of PCDs are useful for prediction of critical spots prone to flooding along roads: i) topography, ii) soil type, and iii) land use. The main drivers among the PCDs considered were a topographical wetness index, road density in the catchment, soil properties in the catchment (mainly the amount of gravel substrate) and local channel slope at the site of a road-stream intersection. These can be proposed as strong indicators for predicting the flood probability in ungauged river basins in this region, but some care is needed in generalising the case study results other potential factors are also likely to influence the flood hazard probability. Overall, the method proposed represents a straightforward and consistent way to estimate flooding hazards to inform both the planning of future roadways and the maintenance of existing roadways.

  15. Simulation and Hydrologic Modeling of Urban Watershed for Flooding Forecast: The case of the Rio das Antas in the city of Anápolis-GO

    Directory of Open Access Journals (Sweden)

    Eduardo Dourado Argolo

    2016-12-01

    Full Text Available The study area is located along the Rio das Antas basin in the city of Anápolis, Goiás. This study exemplifies an urban area exposed to flooding by rainwater. Decline in the permeability of the river basin area is result of significant real state development in recent years. This study proposes to simulate water flows and respective flooding areas along different sections of the River in response to different rainfall intensities. The simulated flow rates are the result of interpretation of land use scenarios and hydrologic modeling of the river basin area. The rational method and the Bernoulli equation were used in the hydraulic simulation model of the computer program HEC-RAS (Hydrologic Engineering Center's River Analysis System...

  16. Estimation of extreme floods : At-site flood estimates by application of a hydrological model and long synthetic series of precipitation and temperature

    OpenAIRE

    Barkved, Line Johanne

    2007-01-01

    Estimation of extreme floods, based on statistical analyses of observed values of flood series, is associated with several problems leading to high uncertainty in the flood estimates. In particular is this related to the length of the observation series and the extrapolation outside the range of observed values, when estimating the rare extreme floods. In many cases, short hydrological records are the common rule rather than the exceptions. This thesis targets at-site, single station, fr...

  17. Assessment of Coastal and Urban Flooding Hazards Applying Extreme Value Analysis and Multivariate Statistical Techniques: A Case Study in Elwood, Australia

    Science.gov (United States)

    Guimarães Nobre, Gabriela; Arnbjerg-Nielsen, Karsten; Rosbjerg, Dan; Madsen, Henrik

    2016-04-01

    Traditionally, flood risk assessment studies have been carried out from a univariate frequency analysis perspective. However, statistical dependence between hydrological variables, such as extreme rainfall and extreme sea surge, is plausible to exist, since both variables to some extent are driven by common meteorological conditions. Aiming to overcome this limitation, multivariate statistical techniques has the potential to combine different sources of flooding in the investigation. The aim of this study was to apply a range of statistical methodologies for analyzing combined extreme hydrological variables that can lead to coastal and urban flooding. The study area is the Elwood Catchment, which is a highly urbanized catchment located in the city of Port Phillip, Melbourne, Australia. The first part of the investigation dealt with the marginal extreme value distributions. Two approaches to extract extreme value series were applied (Annual Maximum and Partial Duration Series), and different probability distribution functions were fit to the observed sample. Results obtained by using the Generalized Pareto distribution demonstrate the ability of the Pareto family to model the extreme events. Advancing into multivariate extreme value analysis, first an investigation regarding the asymptotic properties of extremal dependence was carried out. As a weak positive asymptotic dependence between the bivariate extreme pairs was found, the Conditional method proposed by Heffernan and Tawn (2004) was chosen. This approach is suitable to model bivariate extreme values, which are relatively unlikely to occur together. The results show that the probability of an extreme sea surge occurring during a one-hour intensity extreme precipitation event (or vice versa) can be twice as great as what would occur when assuming independent events. Therefore, presuming independence between these two variables would result in severe underestimation of the flooding risk in the study area.

  18. Investigating the Performance of One- and Two-dimensional Flood Models in a Channelized River Network: A Case Study of the Obion River System

    Science.gov (United States)

    Kalyanapu, A. J.; Dullo, T. T.; Thornton, J. C.; Auld, L. A.

    2015-12-01

    Obion River, is located in the northwestern Tennessee region, and discharges into the Mississippi River. In the past, the river system was largely channelized for agricultural purposes that resulted in increased erosion, loss of wildlife habitat and downstream flood risks. These impacts are now being slowly reversed mainly due to wetland restoration. The river system is characterized by a large network of "loops" around the main channels that hold water either from excess flows or due to flow diversions. Without data on each individual channel, levee, canal, or pond it is not known where the water flows from or to. In some segments along the river, the natural channel has been altered and rerouted by the farmers for their irrigation purposes. Satellite imagery can aid in identifying these features, but its spatial coverage is temporally sparse. All the alterations that have been done to the watershed make it difficult to develop hydraulic models, which could predict flooding and droughts. This is especially true when building one-dimensional (1D) hydraulic models compared to two-dimensional (2D) models, as the former cannot adequately simulate lateral flows in the floodplain and in complex terrains. The objective of this study therefore is to study the performance of 1D and 2D flood models in this complex river system, evaluate the limitations of 1D models and highlight the advantages of 2D models. The study presents the application of HEC-RAS and HEC-2D models developed by the Hydrologic Engineering Center (HEC), a division of the US Army Corps of Engineers. The broader impacts of this study is the development of best practices for developing flood models in channelized river systems and in agricultural watersheds.

  19. A GIS based approach for the prediction of the dam break flood hazard – A case study of Zardezas reservoir “Skikda, Algeria”

    OpenAIRE

    2015-01-01

    The construction of dams in rivers can offer many advantages, however the consequences resulting from their failure could result in major damage, including loss of life and property destruction. To mitigate the threats of dam break it is essential to appreciate the characteristics of the potential flood in realistic manner. In this study an approach based on the integration of hydraulic modelling and GIS has been used to assess the risks resulting from a potential failure of Zardezas dam, a c...

  20. Distillation Column Flooding Predictor

    Energy Technology Data Exchange (ETDEWEB)

    George E. Dzyacky

    2010-11-23

    The Flooding Predictor™ is a patented advanced control technology proven in research at the Separations Research Program, University of Texas at Austin, to increase distillation column throughput by over 6%, while also increasing energy efficiency by 10%. The research was conducted under a U. S. Department of Energy Cooperative Agreement awarded to George Dzyacky of 2ndpoint, LLC. The Flooding Predictor™ works by detecting the incipient flood point and controlling the column closer to its actual hydraulic limit than historical practices have allowed. Further, the technology uses existing column instrumentation, meaning no additional refining infrastructure is required. Refiners often push distillation columns to maximize throughput, improve separation, or simply to achieve day-to-day optimization. Attempting to achieve such operating objectives is a tricky undertaking that can result in flooding. Operators and advanced control strategies alike rely on the conventional use of delta-pressure instrumentation to approximate the column’s approach to flood. But column delta-pressure is more an inference of the column’s approach to flood than it is an actual measurement of it. As a consequence, delta pressure limits are established conservatively in order to operate in a regime where the column is never expected to flood. As a result, there is much “left on the table” when operating in such a regime, i.e. the capacity difference between controlling the column to an upper delta-pressure limit and controlling it to the actual hydraulic limit. The Flooding Predictor™, an innovative pattern recognition technology, controls columns at their actual hydraulic limit, which research shows leads to a throughput increase of over 6%. Controlling closer to the hydraulic limit also permits operation in a sweet spot of increased energy-efficiency. In this region of increased column loading, the Flooding Predictor is able to exploit the benefits of higher liquid

  1. Teleconnection, Regime Shift, and Predictability of Climate Extremes: A Case Study for the Russian Heat Wave and Pakistan Flood in Summer 2010

    Science.gov (United States)

    Lau, W. K.; Reale, O.; Kim, K.

    2011-01-01

    In this talk, we present observational evidence showing that the two major extremes events of the summer of 2010, i.e., the Russian heat wave and the Pakistan flood were physically connected. We find that the Pakistan flood was contributed by a series of unusually heavy rain events over the upper Indus River Basin in July-August. The rainfall regimes shifted from an episodic heavy rain regime in mid-to-late July to a steady heavy rain regime in August. An atmospheric Rossby wave associated with the development of the Russian heat wave was instrumental in spurring the episodic rain events , drawing moisture from the Bay of Bengal and the northern Arabian Sea. The steady rain regime was maintained primarily by monsoon moisture surges from the deep tropics. From experiments with the GEOS-5 forecast system, we assess the predictability of the heavy rain events associated with the Pakistan flood. Preliminary results indicate that there are significantly higher skills in the rainfall forecasts during the episodic heavy rain events in July, compared to the steady rain period in early to mid-August. The change in rainfall predictability may be related to scale interactions between the extratropics and the tropics resulting in a modulation of rainfall predictability by the circulation regimes.

  2. Teleconnection, regime shift, and predictability of climate extremes: A case study for the Russian heat wave and Pakistan flood in summer 2010.

    Science.gov (United States)

    Lau, W. K.; Reale, O.; Kim, K.

    2011-12-01

    In this talk, we present observational evidence showing that the two major extremes events of the summer of 2010, i.e., the Russian heat wave and the Pakistan flood were physically connected. We find that the Pakistan flood was contributed by a series of unusually heavy rain events over the upper Indus River Basin in July-August. The rainfall regimes shifted from an episodic heavy rain regime in mid-to-late July to a steady heavy rain regime in August. An atmospheric Rossby wave associated with the development of the Russian heat wave was instrumental in spurring the episodic rain events , drawing moisture from the Bay of Bengal and the northern Arabian Sea. The steady rain regime was maintained primarily by monsoon moisture surges from the deep tropics. From experiments with the GEOS-5 forecast system, we assess the predictability of the heavy rain events associated with the Pakistan flood. Preliminary results indicate that there are significantly higher skills in the rainfall forecasts during the episodic heavy rain events in July, compared to the steady rain period in early to mid-August. The change in rainfall predictability may be related to scale interactions between the extratropics and the tropics, resulting in a modulation of rainfall predictability by the circulation regimes.

  3. The potential of coordinated reservoir operation for flood mitigation in large basins - A case study on the Bavarian Danube using coupled hydrological-hydrodynamic models

    Science.gov (United States)

    Seibert, S. P.; Skublics, D.; Ehret, U.

    2014-09-01

    The coordinated operation of reservoirs in large-scale river basins has great potential to improve flood mitigation. However, this requires large scale hydrological models to translate the effect of reservoir operation to downstream points of interest, in a quality sufficient for the iterative development of optimized operation strategies. And, of course, it requires reservoirs large enough to make a noticeable impact. In this paper, we present and discuss several methods dealing with these prerequisites for reservoir operation using the example of three major floods in the Bavarian Danube basin (45,000 km2) and nine reservoirs therein: We start by presenting an approach for multi-criteria evaluation of model performance during floods, including aspects of local sensitivity to simulation quality. Then we investigate the potential of joint hydrologic-2d-hydrodynamic modeling to improve model performance. Based on this, we evaluate upper limits of reservoir impact under idealized conditions (perfect knowledge of future rainfall) with two methods: Detailed simulations and statistical analysis of the reservoirs' specific retention volume. Finally, we investigate to what degree reservoir operation strategies optimized for local (downstream vicinity to the reservoir) and regional (at the Danube) points of interest are compatible. With respect to model evaluation, we found that the consideration of local sensitivities to simulation quality added valuable information not included in the other evaluation criteria (Nash-Sutcliffe efficiency and Peak timing). With respect to the second question, adding hydrodynamic models to the model chain did, contrary to our expectations, not improve simulations, despite the fact that under idealized conditions (using observed instead of simulated lateral inflow) the hydrodynamic models clearly outperformed the routing schemes of the hydrological models. Apparently, the advantages of hydrodynamic models could not be fully exploited when

  4. Improving flood risk mapping in Italy: the FloodRisk open-source software

    Science.gov (United States)

    Albano, Raffaele; Mancusi, Leonardo; Craciun, Iulia; Sole, Aurelia; Ozunu, Alexandru

    2017-04-01

    management process, enhancing their awareness. This FOSS approach can promotes transparency and accountability through a process of "guided discovery". Moreover, the immediacy with which information is presented by the qualitative flood risk map, can facilitate and speed up the process of knowledge acquisition. An application of FloodRisk model is showed on a pilot case in "Serio" Valley, (North Italy), and its strengths and limits, in terms of additional efforts required in its application compared with EDQ procedure, have been highlighted focusing on the utility of the results provided for the development of FRMPs. Although they still present limits which prevent the FloodRisk application without critically consider the peculiarities of the investigated area in terms of available knowledge on hazard, exposure and vulnerability, the proposed approach surely produces an increase in available knowledge of flood risk and its drivers. This further information cannot be neglected for defining risk mitigation objectives and strategies. Hence, considering the ongoing efforts in the improvement of data availability and quality, FloodRisk could be a suitable tool for the next revision of flood risk maps due by December 2019, supporting effectively Italian and EU practitioners in the delineation of FRMPs (and for flood risk management in general).

  5. TWO-DIMENSIONAL MODELLING OF ACCIDENTAL FLOOD WAVES PROPAGATION

    Directory of Open Access Journals (Sweden)

    Lorand Catalin STOENESCU

    2011-05-01

    Full Text Available The study presented in this article describes a modern modeling methodology of the propagation of accidental flood waves in case a dam break; this methodology is applied in Romania for the first time for the pilot project „Breaking scenarios of Poiana Uzului dam”. The calculation programs used help us obtain a bidimensional calculation (2D of the propagation of flood waves, taking into consideration the diminishing of the flood wave on a normal direction to the main direction; this diminishing of the flood wave is important in the case of sinuous courses of water or with urban settlements very close to the minor river bed. In the case of Poiana Uzului dam, 2 scenarios were simulated with the help of Ph.D. Eng. Dan Stematiu, plausible scenarios but with very little chances of actually producing. The results were presented as animations with flooded surfaces at certain time steps successively.

  6. Effects of the interannual variations in the flood pulse mediated by hypoxia tolerance: the case of the fish assemblages in the upper Paraná River floodplain

    Directory of Open Access Journals (Sweden)

    Ana Cristina Petry

    Full Text Available The effects of the duration of the floods on abiotic variables and attributes of species tolerant and intolerant to hypoxia (STH and SIH respectively were evaluated in rivers and lakes of the upper Paraná River. Fish were sampled once a year, in six sampling stations, during the high water period from 2000 to 2003. There were overall reductions in dissolved oxygen levels and increases in transparency of water in lakes in years of moderate floods. The duration of floods influenced species differentially based on their tolerance to hypoxia: in moderate floods, richness of STH increased and numerical abundance and biomass of SIH reduced significantly. Opposite relationships were detected between dissolved oxygen and the attributes of STH and SIH. Dissolved oxygen was the best predictor of variability of STH and SIH in years of moderate floods, whereas water transparency predicted significant amounts of STH in years of short floods. Being positively affected by dissolved oxygen reductions, STH seem to take advantages in persisting in seasonally harsh lentic habitats. The incorporation of abiotic data as well the differential tolerance of species to hypoxia would improve further investigations of the effects of interannual variations in the flood pulse on tropical fish assemblagesOs efeitos da duração da cheia sobre algumas variáveis abióticas e atributos das assembleias de peixes (espécies tolerantes e intolerantes à hipóxia, STH e SIH, respectivamente foram avaliados em rios e lagoas do alto rio Paraná. Os peixes foram amostrados uma vez ao ano, em seis localidades, durante o período de águas altas entre 2000 e 2003. Houve reduções generalizadas nos níveis de oxigênio dissolvido e aumentos na transparência da água em lagos em anos de cheias moderadas. A duração das cheias influenciou as espécies diferencialmente em função de sua tolerância à hipóxia: em anos de cheias moderadas, a riqueza das STH aumentou e a abund

  7. Human influenza A(H7N9) virus infection associated with poultry farm, Northeastern China.

    Science.gov (United States)

    Fan, Ming; Huang, Biao; Wang, Ao; Deng, Liquan; Wu, Donglin; Lu, Xinrong; Zhao, Qinglong; Xu, Shuang; Havers, Fiona; Wang, Yanhui; Wu, Jing; Yin, Yuan; Sun, Bingxin; Yao, Jianyi; Xiang, Nijuan

    2014-11-01

    We report on a case of human infection with influenza A(H7N9) virus in Jilin Province in northeastern China. This case was associated with a poultry farm rather than a live bird market, which may point to a new focus for public health surveillance and interventions in this evolving outbreak.

  8. Health impacts of floods.

    Science.gov (United States)

    Du, Weiwei; FitzGerald, Gerard Joseph; Clark, Michele; Hou, Xiang-Yu

    2010-01-01

    Floods are the most common hazard to cause disasters and have led to extensive morbidity and mortality throughout the world. The impact of floods on the human community is related directly to the location and topography of the area, as well as human demographics and characteristics of the built environment. The aim of this study is to identify the health impacts of disasters and the underlying causes of health impacts associated with floods. A conceptual framework is developed that may assist with the development of a rational and comprehensive approach to prevention, mitigation, and management. This study involved an extensive literature review that located >500 references, which were analyzed to identify common themes, findings, and expert views. The findings then were distilled into common themes. The health impacts of floods are wide ranging, and depend on a number of factors. However, the health impacts of a particular flood are specific to the particular context. The immediate health impacts of floods include drowning, injuries, hypothermia, and animal bites. Health risks also are associated with the evacuation of patients, loss of health workers, and loss of health infrastructure including essential drugs and supplies. In the medium-term, infected wounds, complications of injury, poisoning, poor mental health, communicable diseases, and starvation are indirect effects of flooding. In the long-term, chronic disease, disability, poor mental health, and poverty-related diseases including malnutrition are the potential legacy. This article proposes a structured approach to the classification of the health impacts of floods and a conceptual framework that demonstrates the relationships between floods and the direct and indirect health consequences.

  9. Defining the hundred year flood: A Bayesian approach for using historic data to reduce uncertainty in flood frequency estimates

    Science.gov (United States)

    Parkes, Brandon; Demeritt, David

    2016-09-01

    This paper describes a Bayesian statistical model for estimating flood frequency by combining uncertain annual maximum (AMAX) data from a river gauge with estimates of flood peak discharge from various historic sources that predate the period of instrument records. Such historic flood records promise to expand the time series data needed for reducing the uncertainty in return period estimates for extreme events, but the heterogeneity and uncertainty of historic records make them difficult to use alongside Flood Estimation Handbook and other standard methods for generating flood frequency curves from gauge data. Using the flow of the River Eden in Carlisle, Cumbria, UK as a case study, this paper develops a Bayesian model for combining historic flood estimates since 1800 with gauge data since 1967 to estimate the probability of low frequency flood events for the area taking account of uncertainty in the discharge estimates. Results show a reduction in 95% confidence intervals of roughly 50% for annual exceedance probabilities of less than 0.0133 (return periods over 75 years) compared to standard flood frequency estimation methods using solely systematic data. Sensitivity analysis shows the model is sensitive to 2 model parameters both of which are concerned with the historic (pre-systematic) period of the time series. This highlights the importance of adequate consideration of historic channel and floodplain changes or possible bias in estimates of historic flood discharges. The next steps required to roll out this Bayesian approach for operational flood frequency estimation at other sites is also discussed.

  10. Development of flood index by characterisation of flood hydrographs

    Science.gov (United States)

    Bhattacharya, Biswa; Suman, Asadusjjaman

    2015-04-01

    In recent years the world has experienced deaths, large-scale displacement of people, billions of Euros of economic damage, mental stress and ecosystem impacts due to flooding. Global changes (climate change, population and economic growth, and urbanisation) are exacerbating the severity of flooding. The 2010 floods in Pakistan and the 2011 floods in Australia and Thailand demonstrate the need for concerted action in the face of global societal and environmental changes to strengthen resilience against flooding. Due to climatological characteristics there are catchments where flood forecasting may have a relatively limited role and flood event management may have to be trusted upon. For example, in flash flood catchments, which often may be tiny and un-gauged, flood event management often depends on approximate prediction tools such as flash flood guidance (FFG). There are catchments fed largely by flood waters coming from upstream catchments, which are un-gauged or due to data sharing issues in transboundary catchments the flow of information from upstream catchment is limited. Hydrological and hydraulic modelling of these downstream catchments will never be sufficient to provide any required forecasting lead time and alternative tools to support flood event management will be required. In FFG, or similar approaches, the primary motif is to provide guidance by synthesising the historical data. We follow a similar approach to characterise past flood hydrographs to determine a flood index (FI), which varies in space and time with flood magnitude and its propagation. By studying the variation of the index the pockets of high flood risk, requiring attention, can be earmarked beforehand. This approach can be very useful in flood risk management of catchments where information about hydro-meteorological variables is inadequate for any forecasting system. This paper presents the development of FI and its application to several catchments including in Kentucky in the USA

  11. Nogales flood detention study

    Science.gov (United States)

    Norman, Laura M.; Levick, Lainie; Guertin, D. Phillip; Callegary, James; Guadarrama, Jesus Quintanar; Anaya, Claudia Zulema Gil; Prichard, Andrea; Gray, Floyd; Castellanos, Edgar; Tepezano, Edgar; Huth, Hans; Vandervoet, Prescott; Rodriguez, Saul; Nunez, Jose; Atwood, Donald; Granillo, Gilberto Patricio Olivero; Ceballos, Francisco Octavio Gastellum

    2010-01-01

    Flooding in Ambos Nogales often exceeds the capacity of the channel and adjacent land areas, endangering many people. The Nogales Wash is being studied to prevent future flood disasters and detention features are being installed in tributaries of the wash. This paper describes the application of the KINEROS2 model and efforts to understand the capacity of these detention features under various flood and urbanization scenarios. Results depict a reduction in peak flow for the 10-year, 1-hour event based on current land use in tributaries with detention features. However, model results also demonstrate that larger storm events and increasing urbanization will put a strain on the features and limit their effectiveness.

  12. Looking for Similarities Between Lowland (Flash) Floods

    Science.gov (United States)

    Brauer, C.; Teuling, R.; Torfs, P.; Hobbelt, L.; Jansen, F.; Melsen, L.; Uijlenhoet, R.

    2012-12-01

    On 26 August 2010 the eastern part of The Netherlands and the bordering part of Germany were struck by a series of rainfall events. Over an area of 740 km2 more than 120 mm of rainfall were observed in 24 h. We investigated the unprecedented flash flood triggered by this exceptionally heavy rainfall event (return period > 1000 years) in the 6.5 km2 Hupsel Brook catchment, which has been the experimental watershed employed by Wageningen University since the 1960s. This study improved our understanding of the dynamics of such lowland flash floods (Brauer et al., 2011). These observations, however, only show how our experimental catchment behaved and the results cannot be extrapolated directly to different floods in other (neighboring) lowland catchments. Therefore, it is necessary to use the information collected in one well-monitored catchment in combination with data from other, less well monitored catchments to find common signatures which could describe the runoff response during a lowland flood as a function of catchment characteristics. Because of the large spatial extent of the rainfall event in August 2010, many brooks and rivers in the Netherlands and Germany flooded. With data from several catchments we investigated the influence of rainfall and catchment characteristics (such as slope, size and land use) on the reaction of discharge to rainfall. We also investigated the runoff response in these catchments during previous floods by analyzing the relation between storage and discharge and the recession curve. In addition to the flood in August 2010, two other floods occurred in The Netherlands in recently. The three floods occurred in different parts of the country, after different types of rainfall events and with different initial conditions. We selected several catchments during each flood to compare their response and find out if these cases are fundamentally different or that they were produced by the same underlying processes and can be treated in a

  13. Assessment of Flooded Areas Projections and Floods Potential Impacts Applying Remote Sensing Imagery and Demographic Data

    Science.gov (United States)

    Rodriguez, D. A.; Carriello, F.; Fernandes, P. J. F.; Garofolo Lopes, L.; Siqueira Júnior, J. L.

    2016-06-01

    Assessing vulnerability and potential impacts associated with extreme discharges requires an accurate topographic description in order to estimate the extension of flooded areas. However, in most populated regions, topographic data obtained by in-situ measurements is not available. In this case, digital elevation models derived from remote sensing date are usually applied. Moreover, this digital elevation models have intrinsic errors that introduce bigger uncertainty in results than the associated to hydrological projections. On the other hand, estimations of flooded areas through remote sensing images provide accurate information, which could be used for the construction of river level-flooded area relationships regarding vulnerability assessment. In this work, this approach is applied for the city of Porto Velho in the Brazilian Amazonia to assess potential vulnerability to floods associated with climate change projections. The approach is validated using census data, provided by the Brazilian Institute of Geography and Statistics, and information about socio-economical injuries associated to historical floods, provided by the Brazilian Civil Defence. Hydrological projections under climate change are carried out using several downscaling of climate projections as inputs in a hydrological model. Results show more accurate estimation of flood impacts than the obtained using digital elevation models derivate from remote sensing data. This reduces uncertainties in the assessment of vulnerability to floods assoc