WorldWideScience

Sample records for flood assessment area

  1. Flood hazard assessment in areas prone to flash flooding

    Science.gov (United States)

    Kvočka, Davor; Falconer, Roger A.; Bray, Michaela

    2016-04-01

    Contemporary climate projections suggest that there will be an increase in the occurrence of high-intensity rainfall events in the future. These precipitation extremes are usually the main cause for the emergence of extreme flooding, such as flash flooding. Flash floods are among the most unpredictable, violent and fatal natural hazards in the world. Furthermore, it is expected that flash flooding will occur even more frequently in the future due to more frequent development of extreme weather events, which will greatly increase the danger to people caused by flash flooding. This being the case, there will be a need for high resolution flood hazard maps in areas susceptible to flash flooding. This study investigates what type of flood hazard assessment methods should be used for assessing the flood hazard to people caused by flash flooding. Two different types of flood hazard assessment methods were tested: (i) a widely used method based on an empirical analysis, and (ii) a new, physically based and experimentally calibrated method. Two flash flood events were considered herein, namely: the 2004 Boscastle flash flood and the 2007 Železniki flash flood. The results obtained in this study suggest that in the areas susceptible to extreme flooding, the flood hazard assessment should be conducted using methods based on a mechanics-based analysis. In comparison to standard flood hazard assessment methods, these physically based methods: (i) take into account all of the physical forces, which act on a human body in floodwater, (ii) successfully adapt to abrupt changes in the flow regime, which often occur for flash flood events, and (iii) rapidly assess a flood hazard index in a relatively short period of time.

  2. Assessment of flood risk in Tokyo metropolitan area

    Science.gov (United States)

    Hirano, J.; Dairaku, K.

    2013-12-01

    Flood is one of the most significant natural hazards in Japan. The Tokyo metropolitan area has been affected by several large flood disasters. Therefore, investigating potential flood risk in Tokyo metropolitan area is important for development of adaptation strategy for future climate change. We aim to develop a method for evaluating flood risk in Tokyo Metropolitan area by considering effect of historical land use and land cover change, socio-economic change, and climatic change. Ministry of land, infrastructure, transport and tourism in Japan published 'Statistics of flood', which contains data for flood causes, number of damaged houses, area of wetted surface, and total amount of damage for each flood at small municipal level. By using these flood data, we estimated damage by inundation inside a levee for each prefecture based on a statistical method. On the basis of estimated damage, we developed flood risk curves in the Tokyo metropolitan area, representing relationship between damage and exceedance probability of flood for the period 1976-2008 for each prefecture. Based on the flood risk curve, we attempted evaluate potential flood risk in the Tokyo metropolitan area and clarify the cause for regional difference of flood risk. By analyzing flood risk curves, we found out regional differences of flood risk. We identified high flood risk in Tokyo and Saitama prefecture. On the other hand, flood risk was relatively low in Ibaraki and Chiba prefecture. We found that these regional differences of flood risk can be attributed to spatial distribution of entire property value and ratio of damaged housing units in each prefecture.We also attempted to evaluate influence of climate change on potential flood risk by considering variation of precipitation amount and precipitation intensity in the Tokyo metropolitan area. Results shows that we can evaluate potential impact of precipitation change on flood risk with high accuracy by using our methodology. Acknowledgments

  3. Flood Risk Assessment in Urban Areas Based on Spatial Analytics and Social Factors

    Directory of Open Access Journals (Sweden)

    Costas Armenakis

    2017-11-01

    Full Text Available Flood maps alone are not sufficient to determine and assess the risks to people, property, infrastructure, and services due to a flood event. Simply put, the risk is almost zero to minimum if the flooded region is “empty” (i.e., unpopulated, has not properties, no industry, no infrastructure, and no socio-economic activity. High spatial resolution Earth Observation (EO data can contribute to the generation and updating of flood risk maps based on several aspects including population, economic development, and critical infrastructure, which can enhance a city’s flood mitigation and preparedness planning. In this case study for the Don River watershed, Toronto, the flood risk is determined and flood risk index maps are generated by implementing a methodology for estimating risk based on the geographic coverage of the flood hazard, vulnerability of people, and the exposure of large building structures to flood water. Specifically, the spatial flood risk index maps have been generated through analytical spatial modeling which takes into account the areas in which a flood hazard is expected to occur, the terrain’s morphological characteristics, socio-economic parameters based on demographic data, and the density of large building complexes. Generated flood risk maps are verified through visual inspection with 3D city flood maps. Findings illustrate that areas of higher flood risk coincide with areas of high flood hazard and social and building exposure vulnerability.

  4. Flood risk in a changing world - a coupled transdisciplinary modelling framework for flood risk assessment in an Alpine study area

    Science.gov (United States)

    Huttenlau, Matthias; Schneeberger, Klaus; Winter, Benjamin; Pazur, Robert; Förster, Kristian; Achleitner, Stefan; Bolliger, Janine

    2017-04-01

    Devastating flood events have caused substantial economic damage across Europe during past decades. Flood risk management has therefore become a topic of crucial interest across state agencies, research communities and the public sector including insurances. There is consensus that mitigating flood risk relies on impact assessments which quantitatively account for a broad range of aspects in a (changing) environment. Flood risk assessments which take into account the interaction between the drivers climate change, land-use change and socio-economic change might bring new insights to the understanding of the magnitude and spatial characteristic of flood risks. Furthermore, the comparative assessment of different adaptation measures can give valuable information for decision-making. With this contribution we present an inter- and transdisciplinary research project aiming at developing and applying such an impact assessment relying on a coupled modelling framework for the Province of Vorarlberg in Austria. Stakeholder engagement ensures that the final outcomes of our study are accepted and successfully implemented in flood management practice. The study addresses three key questions: (i) What are scenarios of land- use and climate change for the study area? (ii) How will the magnitude and spatial characteristic of future flood risk change as a result of changes in climate and land use? (iii) Are there spatial planning and building-protection measures which effectively reduce future flood risk? The modelling framework has a modular structure comprising modules (i) climate change, (ii) land-use change, (iii) hydrologic modelling, (iv) flood risk analysis, and (v) adaptation measures. Meteorological time series are coupled with spatially explicit scenarios of land-use change to model runoff time series. The runoff time series are combined with impact indicators such as building damages and results are statistically assessed to analyse flood risk scenarios. Thus, the

  5. Assessment of Socioeconomic Vulnerability to Floods in the Bâsca Chiojdului Catchment Area

    Directory of Open Access Journals (Sweden)

    REMUS PRĂVĂLIE

    2014-12-01

    Full Text Available Hydrological risk phenomena such as floods are among the most costly natural disasters worldwide, effects consisting of socioeconomic damages and deaths. The Bâsca Chiojdului catchment area, by its morphometric and hydrographic peculiarities, is prone to generate these hydrological risk phenomena, so there is a high vulnerability in the socioeconomic elements. This paper is focused on the identification of the main socioeconomic elements vulnerable to hydrological risk phenomena such as floods, based on the assessment of their manifestation potential. Thus, following the delimitation of areas with the highest flood occurrence potential (susceptibility to floods, major socioeconomic factors existing in the basin, considering human settlements (constructions, transport infrastructure, and agricultural areas (the most important category, were superimposed. Results showed a high vulnerability for all three exposed socioeconomic elements especially in valley sectors, of which household structures were the most vulnerable, given both their importance and the high number of areas highly exposed to floods (approximately 2,500 houses and outbuildings, out of a total of about 10,250, intersect the most susceptible area to floods in the study area.

  6. Flood impact assessment on the development of Archaia Olympia riparian area in Greece.

    Science.gov (United States)

    Pasaporti, Christina; Podimata, Marianthi; Yannopoulos, Panayotis

    2013-04-01

    A long list of articles in the literature examines several issues of flood risk management and applications of flood scenarios, taking into consideration the climate changes, as well as decision making tools in flood planning. The present study tries to highlight the conversation concerning flood impacts on the development rate of a riparian area. More specifically, Archaia (Ancient) Olympia watershed was selected as a case study area, since it is considered as a region of special interest and international significance. In addition, Alfeios River, which is the longest river of Peloponnisos Peninsula, passes through the plain of Archaia Olympia. Flood risk scenarios allow scientists and practitioners to understand the adverse effects of flooding on development activities such as farming, tourism etc. and infrastructures in the area such as road and railway networks, Flokas dam and the hydroelectric power plant, bridges, settlements and other properties. Flood risks cause adverse consequences on the region of Archaia Olympia (Ancient Olympic stadium) and Natura 2000 site area. Furthermore, SWOT analysis was used in order to quantify multicriteria and socio-economic characteristics of the study area. SWOT analysis, as a planning method, indicates the development perspective by identifying the strengths, weaknesses, threads and opportunities. Subsequent steps in the process of intergraded River Management Plan of Archaia Olympia could be derived from SWOT analysis. The recognition and analysis of hydro-geomorphological influences on riparian development activities can lead to the definition of hazardous and vulnerability zones and special warning equipment. The former information combined with the use of the spatial database for the catchment area of the River Alfeios, which aims to gather multiple watershed data, could serve in preparing the Management Plan of River Basin District 01 where Alfeios R. belongs. Greece has to fulfill the obligation of implementing River

  7. Assessing coastal flood risk and sea level rise impacts at New York City area airports

    Science.gov (United States)

    Ohman, K. A.; Kimball, N.; Osler, M.; Eberbach, S.

    2014-12-01

    Flood risk and sea level rise impacts were assessed for the Port Authority of New York and New Jersey (PANYNJ) at four airports in the New York City area. These airports included John F. Kennedy International, LaGuardia, Newark International, and Teterboro Airports. Quantifying both present day and future flood risk due to climate change and developing flood mitigation alternatives is crucial for the continued operation of these airports. During Hurricane Sandy in October 2012 all four airports were forced to shut down, in part due to coastal flooding. Future climate change and sea level rise effects may result in more frequent shutdowns and disruptions in travel to and from these busy airports. The study examined the effects of the 1%-annual-chance coastal flooding event for present day existing conditions and six different sea level rise scenarios at each airport. Storm surge model outputs from the Federal Emergency Management Agency (FEMA) provided the present day storm surge conditions. 50th and 90thpercentile sea level rise projections from the New York Panel on Climate Change (NPCC) 2013 report were incorporated into storm surge results using linear superposition methods. These projections were evaluated for future years 2025, 2035, and 2055. In addition to the linear superposition approach for storm surge at airports where waves are a potential hazard, one dimensional wave modeling was performed to get the total water level results. Flood hazard and flood depth maps were created based on these results. In addition to assessing overall flooding at each airport, major at-risk infrastructure critical to the continued operation of the airport was identified and a detailed flood vulnerability assessment was performed. This assessment quantified flood impacts in terms of potential critical infrastructure inundation and developed mitigation alternatives to adapt to coastal flooding and future sea level changes. Results from this project are advancing the PANYNJ

  8. Damage assessment methodology for vehicles exposed to flooding in urban areas

    Directory of Open Access Journals (Sweden)

    E. Martínez Gomariz

    2017-10-01

    Full Text Available Urban floods may provoke important damages to vehicles, usually not taken into account within most studies related to urban flood risks damage assessments. Herein a methodology to estimate damages to vehicles exposed to urban floods is presented. After a state-of-the-art review, the most recent damage curves for vehicles developed by the U.S. Army Corps of Engineers (USACE, 2009 are presented as the best adaptive and the most comprehensively performed so far. The proposed methodology is applied to the Spanish municipality of Badalona, framed in the H2020 European Project BINGO. In order to conduct this methodology some aspects such as the vehicular distribution are analyzed within the study area. Finally, Expected Annual Damage (EAD for flooded vehicles is calculated based on inundations related to design storms of different return periods (1, 10, 100 and 500 years.

  9. Flood Assessment Area 3 Radioactive Waste Management Site, Nevada Test Site, Nye County, Nevada

    International Nuclear Information System (INIS)

    NSTec Environmental Management

    2007-01-01

    A flood assessment was conducted at the Area 3 Radioactive Waste Management Site (RWMS) at the Nevada Test Site (NTS) in Nye County, Nevada (Figure 1-1). The study area encompasses the watershed of Yucca Flat, a closed basin approximately 780 square kilometers (km2) (300 square miles) in size. The focus of this effort was on a drainage area of approximately 94 km2 (36 mi2), determined from review of topographic maps and aerial photographs to be the only part of the Yucca Flat watershed that could directly impact the Area 3 RWMS. This smaller area encompasses portions of the Halfpint Range, including Paiute Ridge, Jangle Ridge, Carbonate Ridge, Slanted Buttes, Cockeyed Ridge, and Banded Mountain. The Area 3 RWMS is located on coalescing alluvial fans emanating from this drainage area

  10. Assessment of flood susceptible areas using spatially explicit, probabilistic multi-criteria decision analysis

    Science.gov (United States)

    Tang, Zhongqian; Zhang, Hua; Yi, Shanzhen; Xiao, Yangfan

    2018-03-01

    GIS-based multi-criteria decision analysis (MCDA) is increasingly used to support flood risk assessment. However, conventional GIS-MCDA methods fail to adequately represent spatial variability and are accompanied with considerable uncertainty. It is, thus, important to incorporate spatial variability and uncertainty into GIS-based decision analysis procedures. This research develops a spatially explicit, probabilistic GIS-MCDA approach for the delineation of potentially flood susceptible areas. The approach integrates the probabilistic and the local ordered weighted averaging (OWA) methods via Monte Carlo simulation, to take into account the uncertainty related to criteria weights, spatial heterogeneity of preferences and the risk attitude of the analyst. The approach is applied to a pilot study for the Gucheng County, central China, heavily affected by the hazardous 2012 flood. A GIS database of six geomorphological and hydrometeorological factors for the evaluation of susceptibility was created. Moreover, uncertainty and sensitivity analysis were performed to investigate the robustness of the model. The results indicate that the ensemble method improves the robustness of the model outcomes with respect to variation in criteria weights and identifies which criteria weights are most responsible for the variability of model outcomes. Therefore, the proposed approach is an improvement over the conventional deterministic method and can provides a more rational, objective and unbiased tool for flood susceptibility evaluation.

  11. Fragility analysis of flood protection structures in earthquake and flood prone areas around Cologne, Germany for multi-hazard risk assessment

    Science.gov (United States)

    Tyagunov, Sergey; Vorogushyn, Sergiy; Munoz Jimenez, Cristina; Parolai, Stefano; Fleming, Kevin; Merz, Bruno; Zschau, Jochen

    2013-04-01

    The work presents a methodology for fragility analyses of fluvial earthen dikes in earthquake and flood prone areas. Fragility estimates are being integrated into the multi-hazard (earthquake-flood) risk analysis being undertaken within the framework of the EU FP7 project MATRIX (New Multi-Hazard and Multi-Risk Assessment Methods for Europe) for the city of Cologne, Germany. Scenarios of probable cascading events due to the earthquake-triggered failure of flood protection dikes and the subsequent inundation of surroundings are analyzed for the area between the gauges Andernach and Düsseldorf along the Rhine River. Along this river stretch, urban areas are partly protected by earthen dikes, which may be prone to failure during exceptional floods and/or earthquakes. The seismic fragility of the dikes is considered in terms of liquefaction potential (factor of safety), estimated by the use of the simplified procedure of Seed and Idriss. It is assumed that initiation of liquefaction at any point throughout the earthen dikes' body corresponds to the failure of the dike and, therefore, this should be taken into account for the flood risk calculations. The estimated damage potential of such structures is presented as a two-dimensional surface (as a function of seismic hazard and water level). Uncertainties in geometrical and geotechnical dike parameters are considered within the framework of Monte Carlo simulations. Taking into consideration the spatial configuration of the existing flood protection system within the area under consideration, seismic hazard curves (in terms of PGA) are calculated for sites along the river segment of interest at intervals of 1 km. The obtained estimates are used to calculate the flood risk when considering the temporal coincidence of seismic and flood events. Changes in flood risk for the considered hazard cascade scenarios are quantified and compared to the single-hazard scenarios.

  12. Flood evolution assessment and monitoring using hydrological modelling techniques: analysis of the inundation areas at a regional scale

    Science.gov (United States)

    Podhoranyi, M.; Kuchar, S.; Portero, A.

    2016-08-01

    The primary objective of this study is to present techniques that cover usage of a hydrodynamic model as the main tool for monitoring and assessment of flood events while focusing on modelling of inundation areas. We analyzed the 2010 flood event (14th May - 20th May) that occurred in the Moravian-Silesian region (Czech Republic). Under investigation were four main catchments: Opava, Odra, Olše and Ostravice. Four hydrodynamic models were created and implemented into the Floreon+ platform in order to map inundation areas that arose during the flood event. In order to study the dynamics of the water, we applied an unsteady flow simulation for the entire area (HEC-RAS 4.1). The inundation areas were monitored, evaluated and recorded semi-automatically by means of the Floreon+ platform. We focused on information about the extent and presence of the flood areas. The modeled flooded areas were verified by comparing them with real data from different sources (official reports, aerial photos and hydrological networks). The study confirmed that hydrodynamic modeling is a very useful tool for mapping and monitoring of inundation areas. Overall, our models detected 48 inundation areas during the 2010 flood event.

  13. FEMA DFIRM Flood Hazard Areas

    Data.gov (United States)

    Minnesota Department of Natural Resources — FEMA flood hazard delineations are used by the Federal Emergency Management Agency (FEMA) to designate the Special Flood Hazard Area (SFHA) and for insurance rating...

  14. 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...

  15. Landslide and flood hazard assessment in urban areas of Levoča region (Eastern Slovakia)

    Science.gov (United States)

    Magulova, Barbora; Caporali, Enrica; Bednarik, Martin

    2010-05-01

    The case study presents the use of statistical methods and analysis tools, for hazard assessment of "urbanization units", implemented in a Geographic Information Systems (GIS) environment. As a case study, the Levoča region (Slovakia) is selected. The region, with a total area of about 351 km2, is widely affected by landslides and floods. The problem, for small urbanization areas, is nowadays particularly significant from the socio-economic point of view. It is considered, presently, also an increasing problem, mainly because of climate change and more frequent extreme rainfall events. The geo-hazards are evaluated using a multivariate analysis. The landslide hazard assessment is based on the comparison and subsequent statistical elaboration of territorial dependence among different input factors influencing the instability of the slopes. Particularly, five factors influencing slope stability are evaluated, i.e. lithology, slope aspect, slope angle, hypsographic level and present land use. As a result a new landslide susceptibility map is compiled and different zones of stable, dormant and non-stable areas are defined. For flood hazard map a detailed digital elevation model is created. A compose index of flood hazard is derived from topography, land cover and pedology related data. To estimate flood discharge, time series of stream flow and precipitation measurements are used. The assessment results are prognostic maps of landslide hazard and flood hazard, which presents the optimal base for urbanization planning.

  16. Probabilistic Flood Defence Assessment Tools

    Directory of Open Access Journals (Sweden)

    Slomp Robert

    2016-01-01

    Full Text Available The WTI2017 project is responsible for the development of flood defence assessment tools for the 3600 km of Dutch primary flood defences, dikes/levees, dunes and hydraulic structures. These tools are necessary, as per January 1st 2017, the new flood risk management policy for the Netherlands will be implemented. Then, the seven decades old design practice (maximum water level methodology of 1958 and two decades old safety standards (and maximum hydraulic load methodology of 1996 will formally be replaced by a more risked based approach for the national policy in flood risk management. The formal flood defence assessment is an important part of this new policy, especially for flood defence managers, since national and regional funding for reinforcement is based on this assessment. This new flood defence policy is based on a maximum allowable probability of flooding. For this, a maximum acceptable individual risk was determined at 1/100 000 per year, this is the probability of life loss of for every protected area in the Netherlands. Safety standards of flood defences were then determined based on this acceptable individual risk. The results were adjusted based on information from cost -benefit analysis, societal risk and large scale societal disruption due to the failure of critical infrastructure e.g. power stations. The resulting riskbased flood defence safety standards range from a 300 to a 100 000 year return period for failure. Two policy studies, WV21 (Safety from floods in the 21st century and VNK-2 (the National Flood Risk in 2010 provided the essential information to determine the new risk based safety standards for flood defences. The WTI2017 project will provide the safety assessment tools based on these new standards and is thus an essential element for the implementation of this policy change. A major issue to be tackled was the development of user-friendly tools, as the new assessment is to be carried out by personnel of the

  17. Simple Method for Assessing Spread of Flood Prone Areas under Historical and Future Rainfall in the Upper Citarum Watershed

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    Bambang Dwi Dasanto

    2014-06-01

    Full Text Available From 1931 to 2010 the flood frequency in Upper Citarum Watershed had increased sharply indicating the decline of the wateshed quality. With the change of climate, risk of the flood may get worse. This study aims to determine effective rainfall that caused flooding and to evaluate the impact of future rainfall changes on the flood prone areas. Effective rainfall which contributes to direct runoff (DRO and leads to flooding was determined using regression equation relating the DRO and cumulative rainfall of a number of consecutive days. Mapping the flood prone areas was developed using the GIS techniques. Results showed that the effective rainfall which caused flooding was the rainfall accumulation for four consecutive days before occurrence of peak of DRO. The percentage of accuracy between estimated and actual flood maps was about 76.9%. According to historical rainfall, the flood prone areas spreaded at right and left directions of the Upstream Citarum River. If this area experiences the climate change, the frequency and flood extents will increase. This study can only identify locations and possibility of flood occurrence but it cannot demonstrate widespread of flood inundation precisely. However, this simple approach can evaluate the flood frequency and intensity quite well.

  18. Flood Hazard Areas - High Risk

    Data.gov (United States)

    Department of Homeland Security — The S_Fld_Haz_Ar table contains information about the flood hazards within the study area. A spatial file with locational information also corresponds with this data...

  19. Health Effects of Coastal Storms and Flooding in Urban Areas: A Review and Vulnerability Assessment

    Directory of Open Access Journals (Sweden)

    Kathryn Lane

    2013-01-01

    Full Text Available Coastal storms can take a devastating toll on the public's health. Urban areas like New York City (NYC may be particularly at risk, given their dense population, reliance on transportation, energy infrastructure that is vulnerable to flood damage, and high-rise residential housing, which may be hard-hit by power and utility outages. Climate change will exacerbate these risks in the coming decades. Sea levels are rising due to global warming, which will intensify storm surge. These projections make preparing for the health impacts of storms even more important. We conducted a broad review of the health impacts of US coastal storms to inform climate adaptation planning efforts, with a focus on outcomes relevant to NYC and urban coastal areas, and incorporated some lessons learned from recent experience with Superstorm Sandy. Based on the literature, indicators of health vulnerability were selected and mapped within NYC neighborhoods. Preparing for the broad range of anticipated effects of coastal storms and floods may help reduce the public health burden from these events.

  20. Health effects of coastal storms and flooding in urban areas: a review and vulnerability assessment.

    Science.gov (United States)

    Lane, Kathryn; Charles-Guzman, Kizzy; Wheeler, Katherine; Abid, Zaynah; Graber, Nathan; Matte, Thomas

    2013-01-01

    Coastal storms can take a devastating toll on the public's health. Urban areas like New York City (NYC) may be particularly at risk, given their dense population, reliance on transportation, energy infrastructure that is vulnerable to flood damage, and high-rise residential housing, which may be hard-hit by power and utility outages. Climate change will exacerbate these risks in the coming decades. Sea levels are rising due to global warming, which will intensify storm surge. These projections make preparing for the health impacts of storms even more important. We conducted a broad review of the health impacts of US coastal storms to inform climate adaptation planning efforts, with a focus on outcomes relevant to NYC and urban coastal areas, and incorporated some lessons learned from recent experience with Superstorm Sandy. Based on the literature, indicators of health vulnerability were selected and mapped within NYC neighborhoods. Preparing for the broad range of anticipated effects of coastal storms and floods may help reduce the public health burden from these events.

  1. Reserve Special Flood Hazard Areas (SFHA)

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This vector dataset depicts the 1% annual flood boundary (otherwise known as special flood hazard area or 100 year flood boundary) for its specified area. The data...

  2. Elephant Butte Special Flood Hazard Areas (SFHA)

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This vector dataset depicts the 1% annual flood boundary (otherwise known as special flood hazard area or 100 year flood boundary) for its specified area. The data...

  3. Application of STORMTOOLS's simplified flood inundation model with sea level rise to assess impacts to RI coastal areas

    Science.gov (United States)

    Spaulding, M. L.

    2015-12-01

    The vision for STORMTOOLS is to provide access to a suite of coastal planning tools (numerical models et al), available as a web service, that allows wide spread accessibly and applicability at high resolution for user selected coastal areas of interest. The first product developed under this framework were flood inundation maps, with and without sea level rise, for varying return periods for RI coastal waters. The flood mapping methodology is based on using the water level vs return periods at a primary NOAA water level gauging station and then spatially scaling the values, based on the predictions of high resolution, storm and wave simulations performed by Army Corp of Engineers, North Atlantic Comprehensive Coastal Study (NACCS) for tropical and extratropical storms on an unstructured grid, to estimate inundation levels for varying return periods. The scaling for the RI application used Newport, RI water levels as the reference point. Predictions are provided for once in 25, 50, and 100 yr return periods (at the upper 95% confidence level), with sea level rises of 1, 2, 3, and 5 ft. Simulations have also been performed for historical hurricane events including 1938, Carol (1954), Bob (1991), and Sandy (2012) and nuisance flooding events with return periods of 1, 3, 5, and 10 yr. Access to the flooding maps is via a web based, map viewer that seamlessly covers all coastal waters of the state at one meter resolution. The GIS structure of the map viewer allows overlays of additional relevant data sets (roads and highways, wastewater treatment facilities, schools, hospitals, emergency evacuation routes, etc.) as desired by the user. The simplified flooding maps are publically available and are now being implemented for state and community resilience planning and vulnerability assessment activities in response to climate change impacts.

  4. Flood Damage Assessment in Pearl River Delta Rural Area Application in Huashan Town, Huadu District,Guanghzou during the 2017 5.7 Heavy Rain Storm

    Science.gov (United States)

    Wang, X.

    2017-12-01

    The Pearl River Delta (PRD) in China, the summer rain storm occurs frequently, the flood damage is very serious. Damage assessment is the basis of scientific decision-making in disaster mitigation. All approaches of flood damage analysis contain uncertainties due to the inaccuracies and generalisations used, the lack of data aggravates this problem, making methods very rough. This study presents a detailed flood damage assessment framework in Pearl River Delta rural area, using 2017 "5.7" heavy rain storm event to simulate the process and estimate the flood loss in resident building and property, agriculture production. The framework integrates four modules,1) utilize the remote sensing and statistical yearbook and so on to construct the disaster bearing bodies GIS database; 2) using hydraulics model to simulate the flood extent and depth spatial distribution;3)through field investigation to obtain the flood loss data for all kinds of hazard-affected body, using statistical analysis method to get the damage curves;4)Integrate flood scenarios, disaster bearing bodies GIS database and damage curves to calculate the flood loss estimation value. Using this methodology, in the 2017 "5.7" heavy rain storm event, Huashan Town flood damage loss is underestimate compared with the government report, because of not considering the damage of water conservancy facilities. But the disaster loss value on the spatial distribution is consistent with actual situation. In terms of aggregated values in the whole town, the model is capable of obtaining figures that are within the same order of magnitude. This study produce a flood damage assessment framework taking into account the regional characteristics of PRD rural area, provide a template for future practice. This study only considers the current impacts, the framework should be improved by taking into account socio-economic and climatic changes, as well as implementing adaptation measures to be applied to assess the potential

  5. Torrential Flood Hazards Assessment, Management, And Mitigation, In Wadi Aday, Muscat Area, Sultanate Of Oman, A GIS and RS Approach

    International Nuclear Information System (INIS)

    SalehI, A.S.; AI-Hatrushi, S.M.

    2009-01-01

    Flash flood hazard of Wadi Aday threaten human activities in an important urban area of Muscat City, the capital of Sultanate of Oman. To evaluate and mitigate these floods; Remote Sensing (IKONOS Images), Topographic and Cadastral maps, data of rainfall, floods and other data sources have been used under a GIS environment and manipulated. The study determined the areas under the flood risk, and clarified the risk class and degree for each of human activities object in the lower part of Wadi Aday. In order to mitigate the flood hazards, and to utilize the floods water in such extreme hot desert; the study suggested: establishing two dams and artificial channel added to some methods that reduce the erosion on canyon reach road

  6. Development of flood probability charts for urban drainage network in coastal areas through a simplified joint assessment approach

    Directory of Open Access Journals (Sweden)

    R. Archetti

    2011-10-01

    Full Text Available The operating conditions of urban drainage networks during storm events depend on the hydraulic conveying capacity of conduits and also on downstream boundary conditions. This is particularly true in coastal areas where the level of the receiving water body is directly or indirectly affected by tidal or wave effects. In such cases, not just different rainfall conditions (varying intensity and duration, but also different sea-levels and their effects on the network operation should be considered. This paper aims to study the behaviour of a seaside town storm sewer network, estimating the threshold condition for flooding and proposing a simplified method to assess the urban flooding severity as a function of climate variables. The case study is a portion of the drainage system of Rimini (Italy, implemented and numerically modelled by means of InfoWorks CS code. The hydraulic simulation of the sewerage system identified the percentage of nodes of the drainage system where flooding is expected to occur. Combining these percentages with both climate variables' values has lead to the definition of charts representing the combined degree of risk "rainfall-sea level" for the drainage system under investigation. A final comparison between such charts and the results obtained from a one-year rainfall-sea level time series has demonstrated the reliability of the analysis.

  7. Application of Flood Nomograph for Flood Forecasting in Urban Areas

    Directory of Open Access Journals (Sweden)

    Eui Hoon Lee

    2018-01-01

    Full Text Available Imperviousness has increased due to urbanization, as has the frequency of extreme rainfall events by climate change. Various countermeasures, such as structural and nonstructural measures, are required to prepare for these effects. Flood forecasting is a representative nonstructural measure. Flood forecasting techniques have been developed for the prevention of repetitive flood damage in urban areas. It is difficult to apply some flood forecasting techniques using training processes because training needs to be applied at every usage. The other flood forecasting techniques that use rainfall data predicted by radar are not appropriate for small areas, such as single drainage basins. In this study, a new flood forecasting technique is suggested to reduce flood damage in urban areas. The flood nomograph consists of the first flooding nodes in rainfall runoff simulations with synthetic rainfall data at each duration. When selecting the first flooding node, the initial amount of synthetic rainfall is 1 mm, which increases in 1 mm increments until flooding occurs. The advantage of this flood forecasting technique is its simple application using real-time rainfall data. This technique can be used to prepare a preemptive response in the process of urban flood management.

  8. Multi-source data fusion and modeling to assess and communicate complex flood dynamics to support decision-making for downstream areas of dams: The 2011 hurricane irene and schoharie creek floods, NY

    Science.gov (United States)

    Renschler, Chris S.; Wang, Zhihao

    2017-10-01

    In light of climate and land use change, stakeholders around the world are interested in assessing historic and likely future flood dynamics and flood extents for decision-making in watersheds with dams as well as limited availability of stream gages and costly technical resources. This research evaluates an assessment and communication approach of combining GIS, hydraulic modeling based on latest remote sensing and topographic imagery by comparing the results to an actual flood event and available stream gages. On August 28th 2011, floods caused by Hurricane Irene swept through a large rural area in New York State, leaving thousands of people homeless, devastating towns and cities. Damage was widespread though the estimated and actual floods inundation and associated return period were still unclear since the flooding was artificially increased by flood water release due to fear of a dam break. This research uses the stream section right below the dam between two stream gages North Blenheim and Breakabeen along Schoharie Creek as a case study site to validate the approach. The data fusion approach uses a GIS, commonly available data sources, the hydraulic model HEC-RAS as well as airborne LiDAR data that were collected two days after the flood event (Aug 30, 2011). The aerial imagery of the airborne survey depicts a low flow event as well as the evidence of the record flood such as debris and other signs of damage to validate the hydrologic simulation results with the available stream gauges. Model results were also compared to the official Federal Emergency Management Agency (FEMA) flood scenarios to determine the actual flood return period of the event. The dynamic of the flood levels was then used to visualize the flood and the actual loss of the Old Blenheim Bridge using Google Sketchup. Integration of multi-source data, cross-validation and visualization provides new ways to utilize pre- and post-event remote sensing imagery and hydrologic models to better

  9. Spatial and Temporal Flood Risk Assessment for Decision Making Approach

    Science.gov (United States)

    Azizat, Nazirah; Omar, Wan-Mohd-Sabki Wan

    2018-03-01

    Heavy rainfall, adversely impacting inundation areas, depends on the magnitude of the flood. Significantly, location of settlements, infrastructure and facilities in floodplains result in many regions facing flooding risks. A problem faced by the decision maker in an assessment of flood vulnerability and evaluation of adaptation measures is recurrent flooding in the same areas. Identification of recurrent flooding areas and frequency of floods should be priorities for flood risk management. However, spatial and temporal variability become major factors of uncertainty in flood risk management. Therefore, dynamic and spatial characteristics of these changes in flood impact assessment are important in making decisions about the future of infrastructure development and community life. System dynamics (SD) simulation and hydrodynamic modelling are presented as tools for modelling the dynamic characteristics of flood risk and spatial variability. This paper discusses the integration between spatial and temporal information that is required by the decision maker for the identification of multi-criteria decision problems involving multiple stakeholders.

  10. Mapping flood and flooding potential indices: a methodological approach to identifying areas susceptible to flood and flooding risk. Case study: the Prahova catchment (Romania)

    Science.gov (United States)

    Zaharia, Liliana; Costache, Romulus; Prăvălie, Remus; Ioana-Toroimac, Gabriela

    2017-04-01

    Given that floods continue to cause yearly significant worldwide human and material damages, flood risk mitigation is a key issue and a permanent challenge in developing policies and strategies at various spatial scales. Therefore, a basic phase is elaborating hazard and flood risk maps, documents which are an essential support for flood risk management. The aim of this paper is to develop an approach that allows for the identification of flash-flood and flood-prone susceptible areas based on computing and mapping of two indices: FFPI (Flash-Flood Potential Index) and FPI (Flooding Potential Index). These indices are obtained by integrating in a GIS environment several geographical variables which control runoff (in the case of the FFPI) and favour flooding (in the case of the FPI). The methodology was applied in the upper (mountainous) and middle (hilly) catchment of the Prahova River, a densely populated and socioeconomically well-developed area which has been affected repeatedly by water-related hazards over the past decades. The resulting maps showing the spatialization of the FFPI and FPI allow for the identification of areas with high susceptibility to flashfloods and flooding. This approach can provide useful mapped information, especially for areas (generally large) where there are no flood/hazard risk maps. Moreover, the FFPI and FPI maps can constitute a preliminary step for flood risk and vulnerability assessment.

  11. 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= .

  12. Improving the analysis of social component of flash-floods risk assessment: Application to urban areas of Castilla y León (Spain)

    Science.gov (United States)

    Aroca Jimenez, Estefanía; Bodoque del Pozo, Jose Maria; Garcia Martin, Juan Antonio; Diez Herrero, Andres

    2016-04-01

    The increasing evidence of anthropogenic climate change, the respective intensification of extreme events as well as the increase in human exposure to natural hazards and their vulnerability show that the enhancement of strategies on how to reduce disaster risk and promote adaptation to extreme events is critical to increase resilience. Growing economic losses, high numbers of casualties and the disruption of livelihoods in various places of the world, at an even higher rate than the increase of magnitude and frequency of extreme events, underline that the vulnerability of societies exposed is a key aspect to be considered. Social vulnerability characterizes the predisposition of society to be afflicted by hazards such as floods, being flash floods one of the hazards with the greatest capacity to generate risk. Despite its importance, social vulnerability is often a neglected aspect of traditional risk assessments which mainly focus on economic and structural measures. The aim of this research is to identify those social characteristics which render people vulnerable to flash flood hazards, and consider whether these characteristics are identifiable as local patterns at regional level. The result of this task is a Social Susceptibility Index (SSI) based on susceptibility profiles of the population per township. These profiles are obtained by Hierarchical Segmentation and Latent Class Analysis of demographic and socio-economic information provided by different public organisms. By adding exposure information to SSI, a Social and Infraestructure Flood Vulnerability Index (SIFVI) is created. The methodology proposed here is implemented in the region of Castilla y León (94,226 km2). Townships that are included in this study meet two requirements: i) city centres are affected by an area where potential significant flash-flood risk exists (i.e. villages are crossed by rivers with a longitudinal slope higher than 0.01); ii) city centres are affected by an area with low

  13. An operational procedure for rapid flood risk assessment in Europe

    Science.gov (United States)

    Dottori, Francesco; Kalas, Milan; Salamon, Peter; Bianchi, Alessandra; Alfieri, Lorenzo; Feyen, Luc

    2017-07-01

    The development of methods for rapid flood mapping and risk assessment is a key step to increase the usefulness of flood early warning systems and is crucial for effective emergency response and flood impact mitigation. Currently, flood early warning systems rarely include real-time components to assess potential impacts generated by forecasted flood events. To overcome this limitation, this study describes the benchmarking of an operational procedure for rapid flood risk assessment based on predictions issued by the European Flood Awareness System (EFAS). Daily streamflow forecasts produced for major European river networks are translated into event-based flood hazard maps using a large map catalogue derived from high-resolution hydrodynamic simulations. Flood hazard maps are then combined with exposure and vulnerability information, and the impacts of the forecasted flood events are evaluated in terms of flood-prone areas, economic damage and affected population, infrastructures and cities.An extensive testing of the operational procedure has been carried out by analysing the catastrophic floods of May 2014 in Bosnia-Herzegovina, Croatia and Serbia. The reliability of the flood mapping methodology is tested against satellite-based and report-based flood extent data, while modelled estimates of economic damage and affected population are compared against ground-based estimations. Finally, we evaluate the skill of risk estimates derived from EFAS flood forecasts with different lead times and combinations of probabilistic forecasts. Results highlight the potential of the real-time operational procedure in helping emergency response and management.

  14. A Location Intelligence System for the Assessment of Pluvial Flooding Risk and the Identification of Storm Water Pollutant Sources from Roads in Suburbanised Areas

    Directory of Open Access Journals (Sweden)

    Szymon Szewrański

    2018-06-01

    Full Text Available The interplay of an ever-growing number of inhabitants, sprawl development, soil sealing, changes in urban traffic characteristics, as well as observed climate trends gives rise to more frequent pluvial flooding in cities, a higher run-off of water, and an increasing pollution of surface water. The aim of this research is to develop a location intelligence system for the assessment of pluvial flooding risks and the identification of storm water pollutant sources from roads in newly-developed areas. The system combines geographic information systems and business intelligence software, and it is based on the original Pluvial Flood Risk Assessment tool. The location intelligence system effectively identifies the spatial and temporal distribution of pluvial flood risks, allows to preliminarily evaluate the total run-off from roads, and helps localise potential places for new water management infrastructure. Further improvements concern the modelling of a flow accumulation and drainage system, the application of weather radar precipitation data, and traffic monitoring and modelling.

  15. Truth or Consequences Special Flood Hazard Areas (SFHA)

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This vector dataset depicts the 1% annual flood boundary (otherwise known as special flood hazard area or 100 year flood boundary) for its specified area. The data...

  16. A methodology for urban flood resilience assessment

    Science.gov (United States)

    Lhomme, Serge; Serre, Damien; Diab, Youssef; Laganier, Richard

    2010-05-01

    In Europe, river floods have been increasing in frequency and severity [Szöllösi-Nagy and Zevenbergen, 2005]. Moreover, climate change is expected to exacerbate the frequency and intensity of hydro meteorological disaster [IPCC, 2007]. Despite efforts made to maintain the flood defense assets, we often observe levee failures leading to finally increase flood risk in protected area. Furthermore, flood forecasting models, although benefiting continuous improvements, remain partly inaccurate due to uncertainties arising all along data calculation processes. In the same time, the year 2007 marks a turning point in history: half of the world population now lives in cities (UN-Habitat, 2007). Moreover, the total urban population is expected to double from two to four billion over the next 30 to 35 years (United Nations, 2006). This growing rate is equivalent to the creation of a new city of one million inhabitants every week, and this during the next four decades [Flood resilience Group]. So, this quick urban development coupled with technical failures and climate change have increased flood risk and corresponding challenges to urban flood risk management [Ashley et al., 2007], [Nie et al., 2009]. These circumstances oblige to manage flood risk by integrating new concepts like urban resilience. In recent years, resilience has become a central concept for risk management. This concept has emerged because a more resilient system is less vulnerable to risk and, therefore, more sustainable [Serre et al., 2010]. But urban flood resilience is a concept that has not yet been directly assessed. Therefore, when decision makers decide to use the resilience concept to manage urban flood, they have no tool to help them. That is why this paper proposes a methodology to assess urban flood resilience in order to make this concept operational. Networks affect the well-being of the people and the smooth functioning of services and, more generally, of economical activities. Yet

  17. Return period assessment of urban pluvial floods through modelling of rainfall–flood response

    DEFF Research Database (Denmark)

    Tuyls, Damian Murla; Thorndahl, Søren Liedtke; Rasmussen, Michael Robdrup

    2018-01-01

    Intense rainfall in urban areas can often generate severe flood impacts. Consequently, it is crucial to design systems to minimize potential flood damages. Traditional, simple design of urban drainage systems assumes agreement between rainfall return period and its consequent flood return period......; however, this does not always apply. Hydraulic infrastructures found in urban drainage systems can increase system heterogeneity and perturb the impact of severe rainfall response. In this study, a surface flood return period assessment was carried out at Lystrup (Denmark), which has received the impact...... of flooding in recent years. A 35 years' rainfall dataset together with a coupled 1D/2D surface and network model was used to analyse and assess flood return period response. Results show an ambiguous relation between rainfall and flood return periods indicating that linear rainfall–runoff relationships will...

  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. Living in Prone Flooding Area: in Coastal Areas of Semarang

    Science.gov (United States)

    Tyas, W. P.

    2018-02-01

    When settlements are not able to provide a comfort area to live in, in this case because of a periodic threat of tidal flood coming to certain settlement areas, it is likely that the people still cannot leave the area. This paper explores the leading factors of the attachment of people to the areas, from economic, physical, social and psychological factors, including a place attachment. Therefore, the approach of the problem solution to tackle the tidal flooding in the areas should be also concern and have considerations relate to the factors.

  20. Assessment of flood Response Characteristics to Urbanization and extreme flood events-Typhoons at Cheongju, Chungbuk

    Science.gov (United States)

    Chang, HyungJoon; Lee, Hyosang; Hwang, Myunggyu; Jang, Sukhwan

    2016-04-01

    The changes of land use influence on the flood characteristics, which depend on rainfall runoff procedures in the catchment. This study assesses the changes of flood characteristics due to land use changes between 1997 and 2012. The catchment model (HEC-HMS) is calibrated with flood events of 1990's and 2000's respectively, then the design rainfall of 100, 200, 500year return period are applied to this model, which represent the catchment in 1990's and 2000's, to assess the flood peaks. Then the extreme flood events (i.e., 6 typhoon events) are applied to assess the flood responses. The results of comparison between 1990's and 2000's show that the flood peak and level of 2000's are increasing and time to peak of 2000's is decreasing comparing to those of 1990's :3% to 78% increase in flood peak, 3% in flood level and 10.2% to 16% decrease in time to peak in 100year return period flood. It is due to decreasing of the farmland area (2.18%), mountainous area (8.88%), and increasing of the urbanization of the area (5.86%). This study also estimates the responses to extreme flood events. The results of 2000's show that the increasing of the flood peak and time to peak comparing to 1990's. It indicates that the extreme rainfall is more responsible at unurbanized catchment ( 2000's), which resulting with a 11% increasing of the peak volume. Acknowledgement This research was supported by a grant (11-TI-C06) from Advanced Water Management Research Program funded by Ministry of Land, Infrastructure and Transport of Korean government.

  1. Multi-dimensional flood vulnerability assessment using data envelopment analysis

    Science.gov (United States)

    Zahid, Zalina; Saharizan, Nurul Syuhada; Hamzah, Paezah; Hussin, Siti Aida Sheikh; Khairi, Siti Shaliza Mohd

    2017-11-01

    Malaysia has been greatly impacted by flood during monsoon seasons. Even though flood prone areas are well identified, assessment on the vulnerability of the disaster is lacking. Assessment of flood vulnerability, defined as the potential for loss when a disaster occurs, is addressed in this paper. The focus is on the development of flood vulnerability measurement in 11 states in Peninsular Malaysia using a non-parametric approach of Data Envelopment Analysis. Scores for three dimensions of flood vulnerability (Population Vulnerability, Social Vulnerability and Biophysical) were calculated using secondary data of selected input and output variables across an 11-year period from 2004 to 2014. The results showed that Johor and Pahang were the most vulnerable to flood in terms of Population Vulnerability, followed by Kelantan, the most vulnerable to flood in terms of Social Vulnerability and Kedah, Pahang and Terengganu were the most vulnerable to flood in terms of Biophysical Vulnerability among the eleven states. The results also showed that the state of Johor, Pahang and Kelantan to be most vulnerable across the three dimensions. Flood vulnerability assessment is important as it provides invaluable information that will allow the authority to identify and develop plans for flood mitigation and to reduce the vulnerability of flood at the affected regions.

  2. Climate-proof planning for flood-prone areas : assessing the adaptive capacity of planning institutions in the Netherlands

    NARCIS (Netherlands)

    van den Brink, Margo; Meijerink, Sander; Termeer, Catrien; Gupta, Joyeeta

    It is generally acknowledged that adapting low-lying, flood-prone deltas to the projected impacts of climate change is of great importance. Deltas are densely populated and often subject to high risk. Climate-proof planning is, however, not only a new but also a highly complex task that poses

  3. Climate-proof planning for flood-prone areas: assessing the adaptive capacity of planning institutions in the Netherlands

    NARCIS (Netherlands)

    Brink, van den M.A.; Meijerink, S.; Termeer, C.J.A.M.; Gupta, J.

    2014-01-01

    It is generally acknowledged that adapting lowlying, flood-prone deltas to the projected impacts of climate change is of great importance. Deltas are densely populated and often subject to high risk. Climate-proof planning is, however, not only a new but also a highly complex task that poses

  4. FLOOD SUSCEPTIBILITY ASSESSMENT IN THE NIRAJ BASIN

    Directory of Open Access Journals (Sweden)

    SANDA ROŞCA

    2012-03-01

    Full Text Available Flood susceptibility assessment in the Niraj basin. In the context of global warming and the increasing frequency of extreme weather events, it becomes evident that we have to face natural hazards, such as floods. In the area of Niraj basin this phenomenon is specific both in the spring, because of the snow melting and of the precipitations which come along with the season, and then in the summer because of the torrential precipitations but rarely in autumn and winter. The aim of this paper is to determinate the susceptibility of the zone and obtain a map which will take into consideration the possibility of a flooding. Defining vulnerability can help us understand this type of natural disasters and find the best ways to reduce it. For this purpose we use thematic layers, morphological characteristics (slope and depth fragmentation, hydrological characteristics, geology, pedology (permeability and soil texture, landuse, precipitation data, and human interventions because in this way we have the possibility to use data mining for this purpose. Data mining will allow us to extract new information based on the existing sets of data.The final result will be a thematic map that highlights the areas which are exposed to the flood. Therefore, this map can be used as a support decision for local government or business purposes.

  5. Urban flood return period assessment through rainfall-flood response modelling

    DEFF Research Database (Denmark)

    Murla, Damian; Thorndahl, Søren Liedtke

    Intense rainfall can often cause severe floods, especially in urbanized areas, where population density or large impermeable areas are found. In this context, floods can generate a direct impact in a social-environmental-economic viewpoint. Traditionally, in design of Urban Drainage Systems (UDS......), correlation between return period (RP) of a given rainfall and RP of its consequent flood has been assumed to be linear (e.g.DS/EN752 (2008)). However, this is not always the case. Complex UDS, where diverse hydraulic infrastructures are often found, increase the heterogeneity of system response, which may...... cause an alteration of the mentioned correlation. Consequently, reliability on future urban planning, design and resilience against floods may be also affected by this misassumption. In this study, an assessment of surface flood RP across rainfall RP has been carried out at Lystrup, a urbanized...

  6. 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.

  7. Flood loss assessment in the Kota Tinggi

    International Nuclear Information System (INIS)

    Tam, T H; Ibrahim, A L; Rahman, M Z A; Mazura, Z

    2014-01-01

    Malaysia is free from several destructive and widespread natural disasters but frequently affected by floods, which caused massive flood damage. In 2006 and 2007, an extreme rainfall occured in many parts of Peninsular Malaysia, which caused severe flooding in several major cities. Kota Tinggi was chosen as study area as it is one the seriously affected area in Johor state. The aim of this study is to estimate potential flood damage to physical elements in Kota Tinggi. The flood damage map contains both qualitative and quantitative information which corresponds to the consequences of flooding. This study only focuses on physical elements. Three different damage functions were adopted to calculate the potential flood damage and flood depth is considered as the main parameter. The adopted functions are United States, the Netherlands and Malaysia. The estimated flood damage for housing using United States, the Netherlands and Malaysia was RM 350/m 2 RM 200/m 2 and RM 100/m 2 respectively. These results successfully showed the average flood damage of physical element. Such important information needed by local authority and government for urban spatial planning and aiming to reduce flood risk

  8. Assessment of hyporheic zone, flood-plain, soil-gas, soil, and surface-water contamination at the Old Incinerator Area, Fort Gordon, Georgia, 2009-2010

    Science.gov (United States)

    Guimaraes, Wladmir B.; Falls, W. Fred; Caldwell, Andral W.; Ratliff, W. Hagan; Wellborn, John B.; Landmeyer, James E.

    2011-01-01

    The U.S. Geological Survey, in cooperation with the U.S. Department of the Army Environmental and Natural Resources Management Office of the U.S. Army Signal Center and Fort Gordon, Georgia, assessed the hyporheic zone, flood plain, soil gas, soil, and surface-water for contaminants at the Old Incinerator Area at Fort Gordon, from October 2009 to September 2010. The assessment included the detection of organic contaminants in the hyporheic zone, flood plain, soil gas, and surface water. In addition, the organic contaminant assessment included the analysis of explosives and chemical agents in selected areas. Inorganic contaminants were assessed in soil and surface-water samples. The assessment was conducted to provide environmental contamination data to the U.S. Army at Fort Gordon pursuant to requirements of the Resource Conservation and Recovery Act Part B Hazardous Waste Permit process. Total petroleum hydrocarbons were detected above the method detection level in all 13 samplers deployed in the hyporheic zone and flood plain of an unnamed tributary to Spirit Creek. The combined concentrations of benzene, toluene, ethylbenzene, and total xylene were detected at 3 of the 13 samplers. Other organic compounds detected in one sampler included octane and trichloroethylene. In the passive soil-gas survey, 28 of the 60 samplers detected total petroleum hydrocarbons above the method detection level. Additionally, 11 of the 60 samplers detected the combined masses of benzene, toluene, ethylbenzene, and total xylene above the method detection level. Other compounds detected above the method detection level in the passive soil-gas survey included octane, trimethylbenzene, perchlorethylene, and chloroform. Subsequent to the passive soil-gas survey, six areas determined to have relatively high contaminant mass were selected, and soil-gas samplers were deployed, collected, and analyzed for explosives and chemical agents. No explosives or chemical agents were detected above

  9. Flood Foresight: A near-real time flood monitoring and forecasting tool for rapid and predictive flood impact assessment

    Science.gov (United States)

    Revilla-Romero, Beatriz; Shelton, Kay; Wood, Elizabeth; Berry, Robert; Bevington, John; Hankin, Barry; Lewis, Gavin; Gubbin, Andrew; Griffiths, Samuel; Barnard, Paul; Pinnell, Marc; Huyck, Charles

    2017-04-01

    The hours and days immediately after a major flood event are often chaotic and confusing, with first responders rushing to mobilise emergency responders, provide alleviation assistance and assess loss to assets of interest (e.g., population, buildings or utilities). Preparations in advance of a forthcoming event are becoming increasingly important; early warning systems have been demonstrated to be useful tools for decision markers. The extent of damage, human casualties and economic loss estimates can vary greatly during an event, and the timely availability of an accurate flood extent allows emergency response and resources to be optimised, reduces impacts, and helps prioritise recovery. In the insurance sector, for example, insurers are under pressure to respond in a proactive manner to claims rather than waiting for policyholders to report losses. Even though there is a great demand for flood inundation extents and severity information in different sectors, generating flood footprints for large areas from hydraulic models in real time remains a challenge. While such footprints can be produced in real time using remote sensing, weather conditions and sensor availability limit their ability to capture every single flood event across the globe. In this session, we will present Flood Foresight (www.floodforesight.com), an operational tool developed to meet the universal requirement for rapid geographic information, before, during and after major riverine flood events. The tool provides spatial data with which users can measure their current or predicted impact from an event - at building, basin, national or continental scales. Within Flood Foresight, the Screening component uses global rainfall predictions to provide a regional- to continental-scale view of heavy rainfall events up to a week in advance, alerting the user to potentially hazardous situations relevant to them. The Forecasting component enhances the predictive suite of tools by providing a local

  10. Effect of Urban Green Spaces and Flooded Area Type on Flooding Probability

    Directory of Open Access Journals (Sweden)

    Hyomin Kim

    2016-01-01

    Full Text Available Countermeasures to urban flooding should consider long-term perspectives, because climate change impacts are unpredictable and complex. Urban green spaces have emerged as a potential option to reduce urban flood risks, and their effectiveness has been highlighted in notable urban water management studies. In this study, flooded areas in Seoul, Korea, were divided into four flooded area types by cluster analysis based on topographic and physical characteristics and verified using discriminant analysis. After division by flooded area type, logistic regression analysis was performed to determine how the flooding probability changes with variations in green space area. Type 1 included regions where flooding occurred in a drainage basin that had a flood risk management infrastructure (FRMI. In Type 2, the slope was steep; the TWI (Topographic Wetness Index was relatively low; and soil drainage was favorable. Type 3 represented the gentlest sloping areas, and these were associated with the highest TWI values. In addition, these areas had the worst soil drainage. Type 4 had moderate slopes, imperfect soil drainage and lower than average TWI values. We found that green spaces exerted a considerable influence on urban flooding probabilities in Seoul, and flooding probabilities could be reduced by over 50% depending on the green space area and the locations where green spaces were introduced. Increasing the area of green spaces was the most effective method of decreasing flooding probability in Type 3 areas. In Type 2 areas, the maximum hourly precipitation affected the flooding probability significantly, and the flooding probability in these areas was high despite the extensive green space area. These findings can contribute towards establishing guidelines for urban spatial planning to respond to urban flooding.

  11. An empirical assessment of which inland floods can be managed.

    Science.gov (United States)

    Mogollón, Beatriz; Frimpong, Emmanuel A; Hoegh, Andrew B; Angermeier, Paul L

    2016-02-01

    Riverine flooding is a significant global issue. Although it is well documented that the influence of landscape structure on floods decreases as flood size increases, studies that define a threshold flood-return period, above which landscape features such as topography, land cover and impoundments can curtail floods, are lacking. Further, the relative influences of natural versus built features on floods is poorly understood. Assumptions about the types of floods that can be managed have considerable implications for the cost-effectiveness of decisions to invest in transforming land cover (e.g., reforestation) and in constructing structures (e.g., storm-water ponds) to control floods. This study defines parameters of floods for which changes in landscape structure can have an impact. We compare nine flood-return periods across 31 watersheds with widely varying topography and land cover in the southeastern United States, using long-term hydrologic records (≥20 years). We also assess the effects of built flow-regulating features (best management practices and artificial water bodies) on selected flood metrics across urban watersheds. We show that landscape features affect magnitude and duration of only those floods with return periods ≤10 years, which suggests that larger floods cannot be managed effectively by manipulating landscape structure. Overall, urban watersheds exhibited larger (270 m(3)/s) but quicker (0.41 days) floods than non-urban watersheds (50 m(3)/s and 1.5 days). However, urban watersheds with more flow-regulating features had lower flood magnitudes (154 m(3)/s), but similar flood durations (0.55 days), compared to urban watersheds with fewer flow-regulating features (360 m(3)/s and 0.23 days). Our analysis provides insight into the magnitude, duration and count of floods that can be curtailed by landscape structure and its management. Our findings are relevant to other areas with similar climate, topography, and land use, and can help

  12. An empirical assessment of which inland floods can be managed

    Science.gov (United States)

    Mogollón, Beatriz; Frimpong, Emmanuel A.; Hoegh, Andrew B.; Angermeier, Paul

    2016-01-01

    Riverine flooding is a significant global issue. Although it is well documented that the influence of landscape structure on floods decreases as flood size increases, studies that define a threshold flood-return period, above which landscape features such as topography, land cover and impoundments can curtail floods, are lacking. Further, the relative influences of natural versus built features on floods is poorly understood. Assumptions about the types of floods that can be managed have considerable implications for the cost-effectiveness of decisions to invest in transforming land cover (e.g., reforestation) and in constructing structures (e.g., storm-water ponds) to control floods. This study defines parameters of floods for which changes in landscape structure can have an impact. We compare nine flood-return periods across 31 watersheds with widely varying topography and land cover in the southeastern United States, using long-term hydrologic records (≥20 years). We also assess the effects of built flow-regulating features (best management practices and artificial water bodies) on selected flood metrics across urban watersheds. We show that landscape features affect magnitude and duration of only those floods with return periods ≤10 years, which suggests that larger floods cannot be managed effectively by manipulating landscape structure. Overall, urban watersheds exhibited larger (270 m3/s) but quicker (0.41 days) floods than non-urban watersheds (50 m3/s and 1.5 days). However, urban watersheds with more flow-regulating features had lower flood magnitudes (154 m3/s), but similar flood durations (0.55 days), compared to urban watersheds with fewer flow-regulating features (360 m3/s and 0.23 days). Our analysis provides insight into the magnitude, duration and count of floods that can be curtailed by landscape structure and its management. Our findings are relevant to other areas with similar climate, topography, and land use, and can help ensure that

  13. Flood risk assessment and mapping for the Lebanese watersheds

    Science.gov (United States)

    Abdallah, Chadi; Hdeib, Rouya

    2016-04-01

    Of all natural disasters, floods affect the greatest number of people worldwide and have the greatest potential to cause damage. Nowadays, with the emerging global warming phenomenon, this number is expected to increase. The Eastern Mediterranean area, including Lebanon (10452 Km2, 4.5 M habitant), has witnessed in the past few decades an increase frequency of flooding events. This study profoundly assess the flood risk over Lebanon covering all the 17 major watersheds and a number of small sub-catchments. It evaluate the physical direct tangible damages caused by floods. The risk assessment and evaluation process was carried out over three stages; i) Evaluating Assets at Risk, where the areas and assets vulnerable to flooding are identified, ii) Vulnerability Assessment, where the causes of vulnerability are assessed and the value of the assets are provided, iii) Risk Assessment, where damage functions are established and the consequent damages of flooding are estimated. A detailed Land CoverUse map was prepared at a scale of 1/ 1 000 using 0.4 m resolution satellite images within the flood hazard zones. The detailed field verification enabled to allocate and characterize all elements at risk, identify hotspots, interview local witnesses, and to correlate and calibrate previous flood damages with the utilized models. All filed gathered information was collected through Mobile Application and transformed to be standardized and classified under GIS environment. Consequently; the general damage evaluation and risk maps at different flood recurrence periods (10, 50, 100 years) were established. Major results showed that floods in a winter season (December, January, and February) of 10 year recurrence and of water retention ranging from 1 to 3 days can cause total damages (losses) that reach 1.14 M for crop lands and 2.30 M for green houses. Whereas, it may cause 0.2 M to losses in fruit trees for a flood retention ranging from 3 to 5 days. These numbers differs

  14. Quantitative risk analysis of urban flooding in lowland areas

    NARCIS (Netherlands)

    Ten Veldhuis, J.A.E.

    2010-01-01

    Urban flood risk analyses suffer from a lack of quantitative historical data on flooding incidents. Data collection takes place on an ad hoc basis and is usually restricted to severe events. The resulting data deficiency renders quantitative assessment of urban flood risks uncertain. The study

  15. Assessment of Three Flood Hazard Mapping Methods: A Case Study of Perlis

    Science.gov (United States)

    Azizat, Nazirah; Omar, Wan Mohd Sabki Wan

    2018-03-01

    Flood is a common natural disaster and also affect the all state in Malaysia. Regarding to Drainage and Irrigation Department (DID) in 2007, about 29, 270 km2 or 9 percent of region of the country is prone to flooding. Flood can be such devastating catastrophic which can effected to people, economy and environment. Flood hazard mapping can be used is an important part in flood assessment to define those high risk area prone to flooding. The purposes of this study are to prepare a flood hazard mapping in Perlis and to evaluate flood hazard using frequency ratio, statistical index and Poisson method. The six factors affecting the occurrence of flood including elevation, distance from the drainage network, rainfall, soil texture, geology and erosion were created using ArcGIS 10.1 software. Flood location map in this study has been generated based on flooded area in year 2010 from DID. These parameters and flood location map were analysed to prepare flood hazard mapping in representing the probability of flood area. The results of the analysis were verified using flood location data in year 2013, 2014, 2015. The comparison result showed statistical index method is better in prediction of flood area rather than frequency ratio and Poisson method.

  16. Assessing flood forecast uncertainty with fuzzy arithmetic

    Directory of Open Access Journals (Sweden)

    de Bruyn Bertrand

    2016-01-01

    Full Text Available Providing forecasts for flow rates and water levels during floods have to be associated with uncertainty estimates. The forecast sources of uncertainty are plural. For hydrological forecasts (rainfall-runoff performed using a deterministic hydrological model with basic physics, two main sources can be identified. The first obvious source is the forcing data: rainfall forecast data are supplied in real time by meteorological forecasting services to the Flood Forecasting Service within a range between a lowest and a highest predicted discharge. These two values define an uncertainty interval for the rainfall variable provided on a given watershed. The second source of uncertainty is related to the complexity of the modeled system (the catchment impacted by the hydro-meteorological phenomenon, the number of variables that may describe the problem and their spatial and time variability. The model simplifies the system by reducing the number of variables to a few parameters. Thus it contains an intrinsic uncertainty. This model uncertainty is assessed by comparing simulated and observed rates for a large number of hydro-meteorological events. We propose a method based on fuzzy arithmetic to estimate the possible range of flow rates (and levels of water making a forecast based on possible rainfalls provided by forcing and uncertainty model. The model uncertainty is here expressed as a range of possible values. Both rainfall and model uncertainties are combined with fuzzy arithmetic. This method allows to evaluate the prediction uncertainty range. The Flood Forecasting Service of Oise and Aisne rivers, in particular, monitors the upstream watershed of the Oise at Hirson. This watershed’s area is 310 km2. Its response time is about 10 hours. Several hydrological models are calibrated for flood forecasting in this watershed and use the rainfall forecast. This method presents the advantage to be easily implemented. Moreover, it permits to be carried out

  17. Quantitative flood risk assessment for Polders

    International Nuclear Information System (INIS)

    Manen, Sipke E. van; Brinkhuis, Martine

    2005-01-01

    In the Netherlands, the design of dikes and other water retaining structures is based on an acceptable probability (frequency) of overtopping. In 1993 a new safety concept was introduced based on total flood risk. Risk was defined as the product of probability and consequences. In recent years advanced tools have become available to calculate the actual flood risk of a polder. This paper describes the application of these tools to an existing lowland river area. The complete chain of calculations necessary to estimate the risk of flooding of a polder (or dike ring) is presented. The difficulties in applying the present day tools and the largest uncertainties in the calculations are shown

  18. Quantitative flood risk assessment for Polders

    Energy Technology Data Exchange (ETDEWEB)

    Manen, Sipke E. van [Ministry of Transport, Public Works and Water Management, Bouwdienst Rijkswaterstaat, Griffioenlaan 2, Utrecht 3526 (Netherlands)]. E-mail: s.e.vmanen@bwd.rws.minvenw.nl; Brinkhuis, Martine [Ministry of Transport, Public Works and Water Management, Delft (Netherlands)

    2005-12-01

    In the Netherlands, the design of dikes and other water retaining structures is based on an acceptable probability (frequency) of overtopping. In 1993 a new safety concept was introduced based on total flood risk. Risk was defined as the product of probability and consequences. In recent years advanced tools have become available to calculate the actual flood risk of a polder. This paper describes the application of these tools to an existing lowland river area. The complete chain of calculations necessary to estimate the risk of flooding of a polder (or dike ring) is presented. The difficulties in applying the present day tools and the largest uncertainties in the calculations are shown.

  19. 44 CFR 65.14 - Remapping of areas for which local flood protection systems no longer provide base flood protection.

    Science.gov (United States)

    2010-10-01

    ... local flood protection systems no longer provide base flood protection. 65.14 Section 65.14 Emergency... § 65.14 Remapping of areas for which local flood protection systems no longer provide base flood... process of restoring a flood protection system that was: (i) Constructed using Federal funds; (ii...

  20. Urban flood return period assessment through rainfall-flood response modelling

    Science.gov (United States)

    Murla Tuyls, Damian; Thorndahl, Søren

    2017-04-01

    Intense rainfall can often cause severe floods, especially in urbanized areas, where population density or large impermeable areas are found. In this context, floods can generate a direct impact in a social-environmental-economic viewpoint. Traditionally, in design of Urban Drainage Systems (UDS), correlation between return period (RP) of a given rainfall and RP of its consequent flood has been assumed to be linear (e.g. DS/EN752 (2008)). However, this is not always the case. Complex UDS, where diverse hydraulic infrastructures are often found, increase the heterogeneity of system response, which may cause an alteration of the mentioned correlation. Consequently, reliability on future urban planning, design and resilience against floods may be also affected by this misassumption. In this study, an assessment of surface flood RP across rainfall RP has been carried out at Lystrup, a urbanized catchment area of 440ha and 10.400inhab. located in Jutland (Denmark), which has received the impact of several pluvial flooding in the last recent years. A historical rainfall dataset from the last 35 years from two different rain gauges located at 2 and 10 km from the study area has been provided by the Danish Wastewater Pollution Committee and the Danish Meteorological Institute (DMI). The most extreme 25 rainfall events have been selected through a two-step multi-criteria procedure, ensuring an adequate variability of rainfall, from extreme high peak storms with a short duration to moderate rainfall with longer duration. In addition, a coupled 1D/2D surface and network UDS model of the catchment area developed in an integrated MIKE URBAN and MIKE Flood model (DHI 2014), considering both permeable and impermeable areas, in combination with a DTM (2x2m res.) has been used to study and assess in detail flood RP. Results show an ambiguous relation between rainfall RP and flood response. Local flood levels, flood area and volume RP estimates should therefore not be neglected in

  1. Influence of spreading urbanization in flood areas on flood damage in Slovenia

    International Nuclear Information System (INIS)

    Komac, B; Zorn, M; Natek, K

    2008-01-01

    Damage caused by natural disasters in Slovenia is frequently linked to the ignoring of natural factors in spatial planning. Historically, the construction of buildings and settlements avoided dangerous flood areas, but later we see increasing construction in dangerous areas. During the floods in 1990, the most affected buildings were located on ill-considered locations, and the majority was built in more recent times. A similar situation occurred during the floods of September 2007. Comparing the effects of these floods, we determined that damage was always greater due to the urbanization of flood areas. This process furthermore increasingly limits the 'manoeuvring space' for water management authorities, who due to the torrential nature of Slovenia's rivers can not ensure the required level of safety from flooding for unsuitably located settlements and infrastructure. Every year, the Environmental Agency of the Republic of Slovenia issues more than one thousand permits for interventions in areas that affect the water regime, and through decrees the government allows construction in riparian zones, which is supposedly forbidden by the Law on Water. If we do not take measures with more suitable policies for spatial planning, we will no long have the possibility in future to reduce the negative consequences of floods. Given that torrential floods strike certain Slovene regions every three years on average and that larger floods occur at least once a decade, it is senseless to lay the blame on climate change.

  2. CADYRI, a dynamic mapping tool of human risk associated with flooding in urban areas

    Science.gov (United States)

    Tanguy, M.; Chokmani, K.; Bernier, M.; Poulin, J.

    2013-12-01

    When a flood affects an urban area, the managers and services responsible for public safety need precise and real time information on the localization of the flooded areas, on the submersion heights in those areas, but also on the vulnerability of people exposed to this hazard. Such information is essential for an effective crisis management. Despite a growing interest in this topic over the last 15 years, the development of flood risk assessment tools mainly focused on quantitative modeling of the monetary damages caused by floods to residential buildings or to critical infrastructures. Little attention was paid to the vulnerability of people exposed to flooding but also to the effects of the failure or destruction of critical infrastructures and residential building on people health and security during the disaster. Moreover, these models do not integrate the dynamic features of the flood (extent, submersion heights) and the evolution of human vulnerability in the same mapping tool. Thus, an accurate and precise evaluation of human risk induced by urban flooding is hardly feasible using such models. This study presents CADYRI, a dynamic mapping tool of human risk associated with flooding in urban areas, which fills the actual needs in terms of flood risk evaluation and management. This innovative tool integrates a methodology of flood hazard mapping that simulates, for a given discharge, the associated water level, and subsequently determines the extent of the flooded area and the submersion heights at each point of the flooded area, using a DEM. The dynamics of human vulnerability is then mapped at the household level, according to the characteristics of the flood hazard. Three key components of human vulnerability have been identified and are integrated to CADYRI: 1, the intrinsic vulnerability of the population, estimated by specific socio-economic indicators; 2, the vulnerability of buildings, assessed by their structural features; 3, the vulnerability of

  3. An assessment of flood vulnerability on physical development along ...

    African Journals Online (AJOL)

    Mohammad

    Key words: Drainage channel, flood, risk assessment, vulnerability. INTRODUCTION ... hydraulic and other control structures.” The effects of floods are always ..... An application of Geographic Information System in mapping flood risk zones in ...

  4. Influence of Flood Detention Capability in Flood Prevention for Flood Disaster of Depression Area

    OpenAIRE

    Chia Lin Chan; Yi Ju Yang; Chih Chin Yang

    2011-01-01

    Rainfall records of rainfall station including the rainfall potential per hour and rainfall mass of five heavy storms are explored, respectively from 2001 to 2010. The rationalization formula is to investigate the capability of flood peak duration of flood detention pond in different rainfall conditions. The stable flood detention model is also proposed by using system dynamic control theory to get the message of flood detention pond in this research. When rainfall freque...

  5. A prediction and damage assessment model for snowmelt flood events in middle and high latitudes Region

    Science.gov (United States)

    Qiao, C.; Huang, Q.; Chen, T.; Zhang, X.

    2017-12-01

    In the context of global warming, the snowmelt flood events in the mountainous area of the middle and high latitudes are increasingly frequent and create severe casualties and property damages. Carrying out the prediction and risk assessment of the snowmelt flood is of great importance in the water resources management, the flood warning and prevention. Based on the remote sensing and GIS techniques, the relationships of the variables influencing the snowmelt flood such as the snow area, the snow depth, the air temperature, the precipitation, the land topography and land covers are analyzed and a prediction and damage assessment model for snowmelt floods is developed. This model analyzes and predicts the flood submerging area, flood depth, flood grade, and the damages of different underlying surfaces in the study area in a given time period based on the estimation of snowmelt amount, the snowmelt runoff, the direction and velocity of the flood. Then it was used to predict a snowmelt flood event in the Ertis River Basin in northern Xinjiang, China, during March and June, 2005 and to assess its damages including the damages of roads, transmission lines, settlements caused by the floods and the possible landslides using the hydrological and meteorological data, snow parameter data, DEM data and land use data. A comparison was made between the prediction results from this model and observation data including the flood measurement and its disaster loss data, which suggests that this model performs well in predicting the strength and impact area of snowmelt flood and its damage assessment. This model will be helpful for the prediction and damage assessment of snowmelt flood events in the mountainous area in the middle and high latitudes in spring, which has great social and economic significance because it provides a relatively reliable method for snowmelt flood prediction and reduces the possible damages caused by snowmelt floods.

  6. Uncertainty quantification in flood risk assessment

    Science.gov (United States)

    Blöschl, Günter; Hall, Julia; Kiss, Andrea; Parajka, Juraj; Perdigão, Rui A. P.; Rogger, Magdalena; Salinas, José Luis; Viglione, Alberto

    2017-04-01

    Uncertainty is inherent to flood risk assessments because of the complexity of the human-water system, which is characterised by nonlinearities and interdependencies, because of limited knowledge about system properties and because of cognitive biases in human perception and decision-making. On top of the uncertainty associated with the assessment of the existing risk to extreme events, additional uncertainty arises because of temporal changes in the system due to climate change, modifications of the environment, population growth and the associated increase in assets. Novel risk assessment concepts are needed that take into account all these sources of uncertainty. They should be based on the understanding of how flood extremes are generated and how they change over time. They should also account for the dynamics of risk perception of decision makers and population in the floodplains. In this talk we discuss these novel risk assessment concepts through examples from Flood Frequency Hydrology, Socio-Hydrology and Predictions Under Change. We believe that uncertainty quantification in flood risk assessment should lead to a robust approach of integrated flood risk management aiming at enhancing resilience rather than searching for optimal defense strategies.

  7. Flood characteristics of the Haor area in Bangladesh

    Science.gov (United States)

    Suman, Asadusjjaman; Bhattacharya, Biswa

    2013-04-01

    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. Bangladesh is a country, which is frequently suffering from flooding. The current research is conducted in the framework of a project, which focuses on the flooding issues in the Haor region in the north-east of Bangladesh. A haor is a saucer-shaped depression, which is used during the dry period (December to mid-May) for agriculture and as a fishery during the wet period (June-November), and thereby presents a very interesting socio-economic perspective of flood risk management. Pre-monsoon flooding till mid-May causes agricultural loss and lot of distress whereas monsoon flooding brings benefits. The area is bordering India, thereby presenting trans-boundary issues as well, and is fed by some flashy Indian catchments. The area is drained mainly through 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 impact of climate changes. A 1D2D model, with one-dimensional model for the rivers (based on MIKE 11 modelling tool from Danish Hydraulic Institute) and a two

  8. Keep Children Safe From Drowning in Flooded Areas

    Centers for Disease Control (CDC) Podcasts

    2006-08-10

    As the cleanup process begins after a natural disaster, there may be areas of flooding. Watch your children to prevent them from playing in or around flood water.  Created: 8/10/2006 by Emergency Communications System.   Date Released: 10/22/2007.

  9. 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.

  10. 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

  11. NATURAL HAZARD ASSESSMENT OF SW MYANMAR - A CONTRIBUTION OF REMOTE SENSING AND GIS METHODS TO THE DETECTION OF AREAS VULNERABLE TO EARTHQUAKES AND TSUNAMI / CYCLONE FLOODING

    Directory of Open Access Journals (Sweden)

    George Pararas-Carayannis

    2009-01-01

    Full Text Available Myanmar, formerly Burma, is vulnerable to several natural hazards, such as earthquakes, cyclones, floods, tsunamis and landslides. The present study focuses on geomorphologic and geologic investigations of the south-western region of the country, based on satellite data (Shuttle Radar Topography Mission-SRTM, MODIS and LANDSAT. The main objective is to detect areas vulnerable to inundation by tsunami waves and cyclone surges. Since the region is also vulnerable to earthquake hazards, it is also important to identify seismotectonic patterns, the location of major active faults, and local site conditions that may enhance ground motions and earthquake intensities. As illustrated by this study, linear, topographic features related to subsurface tectonic features become clearly visible on SRTM-derived morphometric maps and on LANDSAT imagery. The GIS integrated evaluation of LANDSAT and SRTM data helps identify areas most susceptible to flooding and inundation by tsunamis and storm surges. Additionally, land elevation maps help identify sites greater than 10 m in elevation height, that would be suitable for the building of protective tsunami/cyclone shelters.

  12. Lessons learned from Khartoum flash flood impacts: An integrated assessment.

    Science.gov (United States)

    Mahmood, Mohamad Ibrahim; Elagib, Nadir Ahmed; Horn, Finlay; Saad, Suhair A G

    2017-12-01

    This study aims at enabling the compilation of key lessons for decision makers and urban planners in rapidly urbanizing cities regarding the identification of representative, chief causal natural and human factors for the increased level of flash flood risk. To achieve this, the impacts of flash flood events of 2013 and 2014 in the capital of Sudan, Khartoum, were assessed using seven integrated approaches, i.e. rainfall data analysis, document analysis of affected people and houses, observational fieldwork in the worst flood affected areas, people's perception of causes and mitigation measures through household interviews, reported drinking water quality, reported water-related diseases and social risk assessment. Several lessons have been developed as follows. Urban planners must recognize the devastating risks of building within natural pathways of ephemeral watercourses. They must also ensure effective drainage infrastructures and physio-geographical investigations prior to developing urban areas. The existing urban drainage systems become ineffective due to blockage by urban waste. Building of unauthorized drainage and embankment structures by locals often cause greater flood problems than normal. The urban runoff is especially problematic for residential areas built within low-lying areas having naturally low infiltration capacity, as surface water can rapidly collect within hollows and depressions, or beside elevated roads that preclude the free flow of floodwater. Weak housing and infrastructure quality are especially vulnerable to flash flooding and even to rainfall directly. Establishment of services infrastructure is imperative for flash flood disaster risk reduction. Water supply should be from lower aquifers to avoid contaminant groundwater. Regular monitoring of water quality and archiving of its indicators help identify water-related diseases and sources of water contamination in the event of environmental disasters such as floods. Though the

  13. Potential of 3D City Models to assess flood vulnerability

    Science.gov (United States)

    Schröter, Kai; Bochow, Mathias; Schüttig, Martin; Nagel, Claus; Ross, Lutz; Kreibich, Heidi

    2016-04-01

    Vulnerability, as the product of exposure and susceptibility, is a key factor of the flood risk equation. Furthermore, the estimation of flood loss is very sensitive to the choice of the vulnerability model. Still, in contrast to elaborate hazard simulations, vulnerability is often considered in a simplified manner concerning the spatial resolution and geo-location of exposed objects as well as the susceptibility of these objects at risk. Usually, area specific potential flood loss is quantified on the level of aggregated land-use classes, and both hazard intensity and resistance characteristics of affected objects are represented in highly simplified terms. We investigate the potential of 3D City Models and spatial features derived from remote sensing data to improve the differentiation of vulnerability in flood risk assessment. 3D City Models are based on CityGML, an application scheme of the Geography Markup Language (GML), which represents the 3D geometry, 3D topology, semantics and appearance of objects on different levels of detail. As such, 3D City Models offer detailed spatial information which is useful to describe the exposure and to characterize the susceptibility of residential buildings at risk. This information is further consolidated with spatial features of the building stock derived from remote sensing data. Using this database a spatially detailed flood vulnerability model is developed by means of data-mining. Empirical flood damage data are used to derive and to validate flood susceptibility models for individual objects. We present first results from a prototype application in the city of Dresden, Germany. The vulnerability modeling based on 3D City Models and remote sensing data is compared i) to the generally accepted good engineering practice based on area specific loss potential and ii) to a highly detailed representation of flood vulnerability based on a building typology using urban structure types. Comparisons are drawn in terms of

  14. A framework for global river flood risk assessments

    Science.gov (United States)

    Winsemius, H. C.; Van Beek, L. P. H.; Jongman, B.; Ward, P. J.; Bouwman, A.

    2013-05-01

    There is an increasing need for strategic global assessments of flood risks in current and future conditions. In this paper, we propose a framework for global flood risk assessment for river floods, which can be applied in current conditions, as well as in future conditions due to climate and socio-economic changes. The framework's goal is to establish flood hazard and impact estimates at a high enough resolution to allow for their combination into a risk estimate, which can be used for strategic global flood risk assessments. The framework estimates hazard at a resolution of ~ 1 km2 using global forcing datasets of the current (or in scenario mode, future) climate, a global hydrological model, a global flood-routing model, and more importantly, an inundation downscaling routine. The second component of the framework combines hazard with flood impact models at the same resolution (e.g. damage, affected GDP, and affected population) to establish indicators for flood risk (e.g. annual expected damage, affected GDP, and affected population). The framework has been applied using the global hydrological model PCR-GLOBWB, which includes an optional global flood routing model DynRout, combined with scenarios from the Integrated Model to Assess the Global Environment (IMAGE). We performed downscaling of the hazard probability distributions to 1 km2 resolution with a new downscaling algorithm, applied on Bangladesh as a first case study application area. We demonstrate the risk assessment approach in Bangladesh based on GDP per capita data, population, and land use maps for 2010 and 2050. Validation of the hazard estimates has been performed using the Dartmouth Flood Observatory database. This was done by comparing a high return period flood with the maximum observed extent, as well as by comparing a time series of a single event with Dartmouth imagery of the event. Validation of modelled damage estimates was performed using observed damage estimates from the EM

  15. A framework for global river flood risk assessments

    Directory of Open Access Journals (Sweden)

    H. C. Winsemius

    2013-05-01

    Full Text Available There is an increasing need for strategic global assessments of flood risks in current and future conditions. In this paper, we propose a framework for global flood risk assessment for river floods, which can be applied in current conditions, as well as in future conditions due to climate and socio-economic changes. The framework's goal is to establish flood hazard and impact estimates at a high enough resolution to allow for their combination into a risk estimate, which can be used for strategic global flood risk assessments. The framework estimates hazard at a resolution of ~ 1 km2 using global forcing datasets of the current (or in scenario mode, future climate, a global hydrological model, a global flood-routing model, and more importantly, an inundation downscaling routine. The second component of the framework combines hazard with flood impact models at the same resolution (e.g. damage, affected GDP, and affected population to establish indicators for flood risk (e.g. annual expected damage, affected GDP, and affected population. The framework has been applied using the global hydrological model PCR-GLOBWB, which includes an optional global flood routing model DynRout, combined with scenarios from the Integrated Model to Assess the Global Environment (IMAGE. We performed downscaling of the hazard probability distributions to 1 km2 resolution with a new downscaling algorithm, applied on Bangladesh as a first case study application area. We demonstrate the risk assessment approach in Bangladesh based on GDP per capita data, population, and land use maps for 2010 and 2050. Validation of the hazard estimates has been performed using the Dartmouth Flood Observatory database. This was done by comparing a high return period flood with the maximum observed extent, as well as by comparing a time series of a single event with Dartmouth imagery of the event. Validation of modelled damage estimates was performed using observed damage estimates from

  16. Evaluation of various modelling approaches in flood routing simulation and flood area mapping

    Science.gov (United States)

    Papaioannou, George; Loukas, Athanasios; Vasiliades, Lampros; Aronica, Giuseppe

    2016-04-01

    An essential process of flood hazard analysis and mapping is the floodplain modelling. The selection of the modelling approach, especially, in complex riverine topographies such as urban and suburban areas, and ungauged watersheds may affect the accuracy of the outcomes in terms of flood depths and flood inundation area. In this study, a sensitivity analysis implemented using several hydraulic-hydrodynamic modelling approaches (1D, 2D, 1D/2D) and the effect of modelling approach on flood modelling and flood mapping was investigated. The digital terrain model (DTMs) used in this study was generated from Terrestrial Laser Scanning (TLS) point cloud data. The modelling approaches included 1-dimensional hydraulic-hydrodynamic models (1D), 2-dimensional hydraulic-hydrodynamic models (2D) and the coupled 1D/2D. The 1D hydraulic-hydrodynamic models used were: HECRAS, MIKE11, LISFLOOD, XPSTORM. The 2D hydraulic-hydrodynamic models used were: MIKE21, MIKE21FM, HECRAS (2D), XPSTORM, LISFLOOD and FLO2d. The coupled 1D/2D models employed were: HECRAS(1D/2D), MIKE11/MIKE21(MIKE FLOOD platform), MIKE11/MIKE21 FM(MIKE FLOOD platform), XPSTORM(1D/2D). The validation process of flood extent achieved with the use of 2x2 contingency tables between simulated and observed flooded area for an extreme historical flash flood event. The skill score Critical Success Index was used in the validation process. The modelling approaches have also been evaluated for simulation time and requested computing power. The methodology has been implemented in a suburban ungauged watershed of Xerias river at Volos-Greece. The results of the analysis indicate the necessity of sensitivity analysis application with the use of different hydraulic-hydrodynamic modelling approaches especially for areas with complex terrain.

  17. Remote Sensing and GIS Assessment of Flood Vulnerability of ...

    African Journals Online (AJOL)

    Lokoja, the Kogi state capital, is located at the Niger-Benue confluence. Hazards erupt when human activities in the confluence area are not properly managed. This article uses the Remote Sensing and GIS technique to assess the flood vulnerability zones of the town using the bench mark minimum and maximum water ...

  18. Interim report on flash floods, Area 5 - Nevada Test Site

    International Nuclear Information System (INIS)

    French, R.H.

    1980-09-01

    Examination of the presently available data indicates that consideration must be given to the possibility of flash floods when siting waste management facilities in Area 5 of the Nevada Test Site. 6 figures, 7 tables

  19. Flash Flood Type Identification within Catchments in Beijing Mountainous Area

    Science.gov (United States)

    Nan, W.

    2017-12-01

    Flash flood is a common type of disaster in mountainous area, Flash flood with the feature of large flow rate, strong flushing force, destructive power, has periodically caused loss to life and destruction to infrastructure in mountainous area. Beijing as China's political, economic and cultural center, the disaster prevention and control work in Beijing mountainous area has always been concerned widely. According to the transport mechanism, sediment concentration and density, the flash flood type identification within catchment can provide basis for making the hazards prevention and mitigation policy. Taking Beijing as the study area, this paper extracted parameters related to catchment morphological and topography features respectively. By using Bayes discriminant, Logistic regression and Random forest, the catchments in Beijing mountainous area were divided into water floods process, fluvial sediment transport process and debris flows process. The results found that Logistic regression analysis showed the highest accuracy, with the overall accuracy of 88.2%. Bayes discriminant and Random forest had poor prediction effects. This study confirmed the ability of morphological and topography features to identify flash flood process. The circularity ratio, elongation ratio and roughness index can be used to explain the flash flood types effectively, and the Melton ratio and elevation relief ratio also did a good job during the identification, whereas the drainage density seemed not to be an issue at this level of detail. Based on the analysis of spatial patterns of flash flood types, fluvial sediment transport process and debris flow process were the dominant hazards, while the pure water flood process was much less. The catchments dominated by fluvial sediment transport process were mainly distributed in the Yan Mountain region, where the fault belts were relatively dense. The debris flow process prone to occur in the Taihang Mountain region thanks to the abundant

  20. Improving Flood Damage Assessment Models in Italy

    Science.gov (United States)

    Amadio, M.; Mysiak, J.; Carrera, L.; Koks, E.

    2015-12-01

    The use of Stage-Damage Curve (SDC) models is prevalent in ex-ante assessments of flood risk. To assess the potential damage of a flood event, SDCs describe a relation between water depth and the associated potential economic damage over land use. This relation is normally developed and calibrated through site-specific analysis based on ex-post damage observations. In some cases (e.g. Italy) SDCs are transferred from other countries, undermining the accuracy and reliability of simulation results. Against this background, we developed a refined SDC model for Northern Italy, underpinned by damage compensation records from a recent flood event. Our analysis considers both damage to physical assets and production losses from business interruptions. While the first is calculated based on land use information, production losses are measured through the spatial distribution of Gross Value Added (GVA). An additional component of the model assesses crop-specific agricultural losses as a function of flood seasonality. Our results show an overestimation of asset damage from non-calibrated SDC values up to a factor of 4.5 for tested land use categories. Furthermore, we estimate that production losses amount to around 6 per cent of the annual GVA. Also, maximum yield losses are less than a half of the amount predicted by the standard SDC methods.

  1. Recent advances in flood forecasting and flood risk assessment

    Directory of Open Access Journals (Sweden)

    G. Arduino

    2005-01-01

    Full Text Available Recent large floods in Europe have led to increased interest in research and development of flood forecasting systems. Some of these events have been provoked by some of the wettest rainfall periods on record which has led to speculation that such extremes are attributable in some measure to anthropogenic global warming and represent the beginning of a period of higher flood frequency. Whilst current trends in extreme event statistics will be difficult to discern, conclusively, there has been a substantial increase in the frequency of high floods in the 20th century for basins greater than 2x105 km2. There is also increasing that anthropogenic forcing of climate change may lead to an increased probability of extreme precipitation and, hence, of flooding. There is, therefore, major emphasis on the improvement of operational flood forecasting systems in Europe, with significant European Community spending on research and development on prototype forecasting systems and flood risk management projects. This Special Issue synthesises the most relevant scientific and technological results presented at the International Conference on Flood Forecasting in Europe held in Rotterdam from 3-5 March 2003. During that meeting 150 scientists, forecasters and stakeholders from four continents assembled to present their work and current operational best practice and to discuss future directions of scientific and technological efforts in flood prediction and prevention. The papers presented at the conference fall into seven themes, as follows.

  2. Multiple flood vulnerability assessment approach based on fuzzy comprehensive evaluation method and coordinated development degree model.

    Science.gov (United States)

    Yang, Weichao; Xu, Kui; Lian, Jijian; Bin, Lingling; Ma, Chao

    2018-05-01

    Flood is a serious challenge that increasingly affects the residents as well as policymakers. Flood vulnerability assessment is becoming gradually relevant in the world. The purpose of this study is to develop an approach to reveal the relationship between exposure, sensitivity and adaptive capacity for better flood vulnerability assessment, based on the fuzzy comprehensive evaluation method (FCEM) and coordinated development degree model (CDDM). The approach is organized into three parts: establishment of index system, assessment of exposure, sensitivity and adaptive capacity, and multiple flood vulnerability assessment. Hydrodynamic model and statistical data are employed for the establishment of index system; FCEM is used to evaluate exposure, sensitivity and adaptive capacity; and CDDM is applied to express the relationship of the three components of vulnerability. Six multiple flood vulnerability types and four levels are proposed to assess flood vulnerability from multiple perspectives. Then the approach is applied to assess the spatiality of flood vulnerability in Hainan's eastern area, China. Based on the results of multiple flood vulnerability, a decision-making process for rational allocation of limited resources is proposed and applied to the study area. The study shows that multiple flood vulnerability assessment can evaluate vulnerability more completely, and help decision makers learn more information about making decisions in a more comprehensive way. In summary, this study provides a new way for flood vulnerability assessment and disaster prevention decision. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Development of a precipitation-area curve for warning criteria of short-duration flash flood

    Science.gov (United States)

    Bae, Deg-Hyo; Lee, Moon-Hwan; Moon, Sung-Keun

    2018-01-01

    This paper presents quantitative criteria for flash flood warning that can be used to rapidly assess flash flood occurrence based on only rainfall estimates. This study was conducted for 200 small mountainous sub-catchments of the Han River basin in South Korea because South Korea has recently suffered many flash flood events. The quantitative criteria are calculated based on flash flood guidance (FFG), which is defined as the depth of rainfall of a given duration required to cause frequent flooding (1-2-year return period) at the outlet of a small stream basin and is estimated using threshold runoff (TR) and antecedent soil moisture conditions in all sub-basins. The soil moisture conditions were estimated during the flooding season, i.e., July, August and September, over 7 years (2002-2009) using the Sejong University Rainfall Runoff (SURR) model. A ROC (receiver operating characteristic) analysis was used to obtain optimum rainfall values and a generalized precipitation-area (P-A) curve was developed for flash flood warning thresholds. The threshold function was derived as a P-A curve because the precipitation threshold with a short duration is more closely related to basin area than any other variables. For a brief description of the P-A curve, generalized thresholds for flash flood warnings can be suggested for rainfall rates of 42, 32 and 20 mm h-1 in sub-basins with areas of 22-40, 40-100 and > 100 km2, respectively. The proposed P-A curve was validated based on observed flash flood events in different sub-basins. Flash flood occurrences were captured for 9 out of 12 events. This result can be used instead of FFG to identify brief flash flood (less than 1 h), and it can provide warning information to decision-makers or citizens that is relatively simple, clear and immediate.

  4. Flood Risk Assessment Based On Security Deficit Analysis

    Science.gov (United States)

    Beck, J.; Metzger, R.; Hingray, B.; Musy, A.

    Risk is a human perception: a given risk may be considered as acceptable or unac- ceptable depending on the group that has to face that risk. Flood risk analysis of- ten estimates economic losses from damages, but neglects the question of accept- able/unacceptable risk. With input from land use managers, politicians and other stakeholders, risk assessment based on security deficit analysis determines objects with unacceptable risk and their degree of security deficit. Such a risk assessment methodology, initially developed by the Swiss federal authorities, is illustrated by its application on a reach of the Alzette River (Luxembourg) in the framework of the IRMA-SPONGE FRHYMAP project. Flood risk assessment always involves a flood hazard analysis, an exposed object vulnerability analysis, and an analysis combing the results of these two previous analyses. The flood hazard analysis was done with the quasi-2D hydraulic model FldPln to produce flood intensity maps. Flood intensity was determined by the water height and velocity. Object data for the vulnerability analysis, provided by the Luxembourg government, were classified according to their potential damage. Potential damage is expressed in terms of direct, human life and secondary losses. A thematic map was produced to show the object classification. Protection goals were then attributed to the object classes. Protection goals are assigned in terms of an acceptable flood intensity for a certain flood frequency. This is where input from land use managers and politicians comes into play. The perception of risk in the re- gion or country influences the protection goal assignment. Protection goals as used in Switzerland were used in this project. Thematic maps showing the protection goals of each object in the case study area for a given flood frequency were produced. Com- parison between an object's protection goal and the intensity of the flood that touched the object determine the acceptability of the risk and the

  5. Hydrological and hydraulic models for determination of flood-prone and flood inundation areas

    Science.gov (United States)

    Aksoy, Hafzullah; Sadan Ozgur Kirca, Veysel; Burgan, Halil Ibrahim; Kellecioglu, Dorukhan

    2016-05-01

    Geographic Information Systems (GIS) are widely used in most studies on water resources. Especially, when the topography and geomorphology of study area are considered, GIS can ease the work load. Detailed data should be used in this kind of studies. Because of, either the complication of the models or the requirement of highly detailed data, model outputs can be obtained fast only with a good optimization. The aim in this study, firstly, is to determine flood-prone areas in a watershed by using a hydrological model considering two wetness indexes; the topographical wetness index, and the SAGA (System for Automated Geoscientific Analyses) wetness index. The wetness indexes were obtained in the Quantum GIS (QGIS) software by using the Digital Elevation Model of the study area. Flood-prone areas are determined by considering the wetness index maps of the watershed. As the second stage of this study, a hydraulic model, HEC-RAS, was executed to determine flood inundation areas under different return period-flood events. River network cross-sections required for this study were derived from highly detailed digital elevation models by QGIS. Also river hydraulic parameters were used in the hydraulic model. Modelling technology used in this study is made of freely available open source softwares. Based on case studies performed on watersheds in Turkey, it is concluded that results of such studies can be used for taking precaution measures against life and monetary losses due to floods in urban areas particularly.

  6. Hydrological and hydraulic models for determination of flood-prone and flood inundation areas

    Directory of Open Access Journals (Sweden)

    H. Aksoy

    2016-05-01

    Full Text Available Geographic Information Systems (GIS are widely used in most studies on water resources. Especially, when the topography and geomorphology of study area are considered, GIS can ease the work load. Detailed data should be used in this kind of studies. Because of, either the complication of the models or the requirement of highly detailed data, model outputs can be obtained fast only with a good optimization. The aim in this study, firstly, is to determine flood-prone areas in a watershed by using a hydrological model considering two wetness indexes; the topographical wetness index, and the SAGA (System for Automated Geoscientific Analyses wetness index. The wetness indexes were obtained in the Quantum GIS (QGIS software by using the Digital Elevation Model of the study area. Flood-prone areas are determined by considering the wetness index maps of the watershed. As the second stage of this study, a hydraulic model, HEC-RAS, was executed to determine flood inundation areas under different return period-flood events. River network cross-sections required for this study were derived from highly detailed digital elevation models by QGIS. Also river hydraulic parameters were used in the hydraulic model. Modelling technology used in this study is made of freely available open source softwares. Based on case studies performed on watersheds in Turkey, it is concluded that results of such studies can be used for taking precaution measures against life and monetary losses due to floods in urban areas particularly.

  7. Assess the flood resilience tools integration in the landuse projects

    Science.gov (United States)

    Moulin, E.; Deroubaix, J.-F.

    2012-04-01

    Despite a severe regulation concerning the building in flooding areas, 80% of these areas are already built in the Greater Paris (Paris, Val-de-Marne, Hauts-de-Seine and Seine-Saint-Denis). The land use in flooding area is presented as one of the main solutions to solve the ongoing real estate pressure. For instance some of the industrial wastelands located along the river are currently in redevelopment and residential buildings are planned. So the landuse in the flooding areas is currently a key issue in the development of the Greater Paris area. To deal with floods there are some resilience tools, whether structural (such as perimeter barriers or building aperture barriers, etc) or non structural (such as warning systems, etc.). The technical solutions are available and most of the time efficient1. Still, we notice that these tools are not much implemented. The people; stakeholders and inhabitants, literally seems to be not interested. This papers focus on the integration of resilience tools in urban projects. Indeed one of the blockages in the implementation of an efficient flood risk prevention policy is the lack of concern of the landuse stakeholders and the inhabitants for the risk2. We conducted an important number of interviews with stakeholders involved in various urban projects and we assess, in this communication, to what extent the improvement of the resilience to floods is considered as a main issue in the execution of an urban project? How this concern is maintained or could be maintained throughout the project. Is there a dilution of this concern? In order to develop this topic we rely on a case study. The "Ardoines" is a project aiming at redeveloping an industrial site (South-East Paris), into a project including residential and office buildings and other amenities. In order to elaborate the master plan, the urban planning authority brought together some flood risk experts. According to the comments of the experts, the architect in charge of the

  8. Weighted normalized risk factor for floods risk assessment

    Directory of Open Access Journals (Sweden)

    Ashraf Mohamed Elmoustafa

    2012-12-01

    Full Text Available Multi Criteria Analysis (MCA describes any structured approach used to determine overall preferences among alternative options, where options accomplish certain or several objectives. The flood protection of properties is a highly important issue due to the damage, danger and other hazards associated to it to human life, properties, and environment. To determine the priority of execution of protection works for any project, many aspects should be considered in order to decide the areas to start the data collection and analysis with. Multi criteria analysis techniques were tested and evaluated for the purpose of flood risk assessment, hydro-morphological parameters were used in this analysis. Finally a suitable technique was chosen and tested to be adopted as a mark of flood risk level and results were presented.

  9. A global framework for future costs and benefits of river-flood protection in urban areas

    Science.gov (United States)

    Ward, Philip J.; Jongman, Brenden; Aerts, Jeroen C. J. H.; Bates, Paul D.; Botzen, Wouter J. W.; Diaz Loaiza, Andres; Hallegatte, Stephane; Kind, Jarl M.; Kwadijk, Jaap; Scussolini, Paolo; Winsemius, Hessel C.

    2017-09-01

    Floods cause billions of dollars of damage each year, and flood risks are expected to increase due to socio-economic development, subsidence, and climate change. Implementing additional flood risk management measures can limit losses, protecting people and livelihoods. Whilst several models have been developed to assess global-scale river-flood risk, methods for evaluating flood risk management investments globally are lacking. Here, we present a framework for assessing costs and benefits of structural flood protection measures in urban areas around the world. We demonstrate its use under different assumptions of current and future climate change and socio-economic development. Under these assumptions, investments in dykes may be economically attractive for reducing risk in large parts of the world, but not everywhere. In some regions, economically efficient investments could reduce future flood risk below today’s levels, in spite of climate change and economic growth. We also demonstrate the sensitivity of the results to different assumptions and parameters. The framework can be used to identify regions where river-flood protection investments should be prioritized, or where other risk-reducing strategies should be emphasized.

  10. Flood Risk and Probabilistic Benefit Assessment to Support Management of Flood-Prone Lands: Evidence From Candaba Floodplains, Philippines

    Science.gov (United States)

    Juarez, A. M.; Kibler, K. M.; Sayama, T.; Ohara, M.

    2016-12-01

    Flood management decision-making is often supported by risk assessment, which may overlook the role of coping capacity and the potential benefits derived from direct use of flood-prone land. Alternatively, risk-benefit analysis can support floodplain management to yield maximum socio-ecological benefits for the minimum flood risk. We evaluate flood risk-probabilistic benefit tradeoffs of livelihood practices compatible with direct human use of flood-prone land (agriculture/wild fisheries) and nature conservation (wild fisheries only) in Candaba, Philippines. Located north-west to Metro Manila, Candaba area is a multi-functional landscape that provides a temporally-variable mix of possible land uses, benefits and ecosystem services of local and regional value. To characterize inundation from 1.3- to 100-year recurrence intervals we couple frequency analysis with rainfall-runoff-inundation modelling and remotely-sensed data. By combining simulated probabilistic floods with both damage and benefit functions (e.g. fish capture and rice yield with flood intensity) we estimate potential damages and benefits over varying probabilistic flood hazards. We find that although direct human uses of flood-prone land are associated with damages, for all the investigated magnitudes of flood events with different frequencies, the probabilistic benefits ( 91 million) exceed risks by a large margin ( 33 million). Even considering risk, probabilistic livelihood benefits of direct human uses far exceed benefits provided by scenarios that exclude direct "risky" human uses (difference of 85 million). In addition, we find that individual coping strategies, such as adapting crop planting periods to the flood pulse or fishing rather than cultivating rice in the wet season, minimize flood losses ( 6 million) while allowing for valuable livelihood benefits ($ 125 million) in flood-prone land. Analysis of societal benefits and local capacities to cope with regular floods demonstrate the

  11. FORECAST OF THE DYNAMICS FLOODING OF THE CRIMEAN AREA DURING OF FLASH FLOODS IN 2012ON THE BASIS COMPUTER SIMULATION

    Directory of Open Access Journals (Sweden)

    E. O. Agafonnikova

    2014-01-01

    Full Text Available The dynamics features of the surface waters for the territory of the Crimea area of Krasnodar region in flash flood conditions have been studied. The parameters of flooding depending on the precipitation intensity have been defined.

  12. 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.

  13. 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.

  14. 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

  15. IMPACT ASSESSMENT OF STRUCTURAL FLOOD MITIGATION MEASURES

    Directory of Open Access Journals (Sweden)

    ZVIJAKOVA LENKA

    2015-03-01

    Full Text Available The objective of the paper is to propose a methodology for assessing water constructions, which will allow impact assessment of water constructions on the environment and hence select the best option for the permission process. The result is “Guideline for environmental impact assessment of flood protection object”, which uses the method of UMRA (universal matrix of risk analysis, which is one of the methods of risk analysis proposed not only to enhance the transparency and sensitivity of the evaluation process, but also to cope with the requirements of the EIA system in the Slovakia and Europe Union.

  16. A framework for global river flood risk assessments

    NARCIS (Netherlands)

    Winsemius, H.C.; van Beek, L.P.H.|info:eu-repo/dai/nl/14749799X; Jongman, B.; Ward, P.J.; Bouwman, A.

    2013-01-01

    There is an increasing need for strategic global assessments of flood risks in current and future conditions. In this paper, we propose a framework for global flood risk assessment for river floods, which can be applied in current conditions, as well as in future conditions due to climate and

  17. FINANCING OF THE FLOOD DEFENSE IN DABULENI-CETATE AREA

    Directory of Open Access Journals (Sweden)

    Dorin COSMA

    2014-11-01

    Full Text Available Danube River Basin has been frequently affected by floods in the last decades which often gained historical meanings, the latest being recorded in 2006 and 2013. The material losses were very high and on the Cetate-Dabuleni sector of the Danube river, after the floods of 2006 the dikes have been damaged and partially destroyed. In the end the Rast locality was almost total relocated. Following these events, we need to rebuild the flood defense infrastructure in the Lower Danube, but after the first assessment the costs are very high. With this paper we propose the ways of funding the flood protection works on the Lower Danube, research being done on the Cetate-Dabuleni Danube's sector.

  18. "Flooding Risk Analysis and the Understanding of Hydrological Disturbance due to the Rapid Urbanization in a Low-Scale Subwatershed in Houston Area". ( The project develops a relavant Model of flooding risk assessment to define the connection between increased streamflow/flooding and the rapid urban land development).

    Science.gov (United States)

    Geldiyev, P.

    2017-12-01

    Rapid urban development and changing climate influences the frequency and magnitude of flooding in Houston area. This proposed project aims to evaluate the flooding risks with the current and future land use changes by 2040 for one subbasin of the San Jacinto Brazos/Neches-Trinity Coastal basin. Surface environments and streamflow data of the Clear Creek are analyzed and stimulated to discuss the possible impact of urbanization on the occurrence of floods. The streamflow data is analyzed and simulated with the application of the Geographic Information Systems and its extensions. Both hydrologic and hydraulic models of the Clear Creek are created with the use of HEC-HMS and HEC-RAS software. Both models are duplicated for the year 2040, based on projected 2040 Landcover Maps developed by Houston and Galveston Area Council. This project examines a type of contemporary hydrologic disturbance and the interaction between land cover and changes in hydrological processes. Expected results will be very significant for urban development and flooding management.

  19. Flood risk management in Flanders: from flood risk objectives to appropriate measures through state assessment

    Directory of Open Access Journals (Sweden)

    Verbeke Sven

    2016-01-01

    Full Text Available In compliance with the EU Flood Directive to reduce flood risk, flood risk management objectives are indispensable for the delineation of necessary measures. In Flanders, flood risk management objectives are part of the environmental objectives which are judicially integrated by the Decree on Integrated Water Policy. Appropriate objectives were derived by supporting studies and extensive consultation on a local, regional and policy level. Under a general flood risk objective sub-objectives are formulated for different aspects: water management and safety, shipping, ecology, and water supply. By developing a risk matrix, it is possible to assess the current state of flood risk and to judge where action is needed to decrease the risk. Three different states of flood risk are distinguished: a acceptable risk, where no action is needed, b intermediate risk where the risk should be reduced by cost efficient actions, and c unacceptable risk, where action is necessary. For each particular aspect, the severity of the consequences of flooding is assessed by quantifiable indicators, such as economic risk, people at risk and ecological flood tolerance. The framework also allows evaluating the effects of the implemented measures and the autonomous development such as climate change and land use change. This approach gives a quantifiable assessment of state, and enables a prioritization of flood risk measures for the reduction of flood risk in a cost efficient and sustainable way.

  20. Flood Hazard and Risk Analysis in Urban Area

    Science.gov (United States)

    Huang, Chen-Jia; Hsu, Ming-hsi; Teng, Wei-Hsien; Lin, Tsung-Hsien

    2017-04-01

    Typhoons always induce heavy rainfall during summer and autumn seasons in Taiwan. Extreme weather in recent years often causes severe flooding which result in serious losses of life and property. With the rapid industrial and commercial development, people care about not only the quality of life, but also the safety of life and property. So the impact of life and property due to disaster is the most serious problem concerned by the residents. For the mitigation of the disaster impact, the flood hazard and risk analysis play an important role for the disaster prevention and mitigation. In this study, the vulnerability of Kaohsiung city was evaluated by statistics of social development factor. The hazard factors of Kaohsiung city was calculated by simulated flood depth of six different return periods and four typhoon events which result in serious flooding in Kaohsiung city. The flood risk can be obtained by means of the flood hazard and social vulnerability. The analysis results provide authority to strengthen disaster preparedness and to set up more resources in high risk areas.

  1. 44 CFR 65.13 - Mapping and map revisions for areas subject to alluvial fan flooding.

    Science.gov (United States)

    2010-10-01

    ... areas subject to alluvial fan flooding. 65.13 Section 65.13 Emergency Management and Assistance FEDERAL... areas subject to alluvial fan flooding. This section describes the procedures to be followed and the... provides protection from the base flood in an area subject to alluvial fan flooding. This information must...

  2. Assessment of flood mitigation through riparian detention in ...

    Indian Academy of Sciences (India)

    19

    changing climate – a case study. 2. 3. Kwan Tun ... expected to mitigate flood damage in downstream urban areas. In this study ... recognized as the most vulnerable region in respect of natural disasters. In the main ..... An integrated numerical model was developed in this study for flooding simulation to realize. 21 the flood ...

  3. September 2013 Storm and Flood Assessment Report

    Energy Technology Data Exchange (ETDEWEB)

    Walterscheid, J. C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-12-21

    Between September 10 and 17, 2013, New Mexico and Colorado received a historically large amount of precipitation (Figure 1). This report assesses the damage caused by flooding along with estimated costs to repair the damage at Los Alamos National Laboratory (the Laboratory) on the Pajarito Plateau. Los Alamos County, New Mexico, received between 200% and 600% of the normal precipitation for this time period (Figure 2), and the Laboratory received approximately 450% percent of its average precipitation for September (Figure 3). As a result, the Laboratory was inundated with rain, including the extremely large, greater-than-1000-yr return period event that occurred between September 12 and 13 (Table 1). With saturated antecedent soil conditions from the September 10 storm, when the September 12 to September 13 storm hit, the flooding was disastrous to the Laboratory’s environmental infrastructure, including access roads, gage stations, watershed controls, control measures installed under the National Pollutant Discharge Elimination System Permit (hereafter, the Individual Permit), and groundwater monitoring wells (Figures 4 through 21). From September 16 to October 1, 2013, the Laboratory completed field assessments of environmental infrastructure and generated descriptions and estimates of the damage, which are presented in spreadsheets in Attachments 1 to 4 of this report. Section 2 of this report contains damage assessments by watershed, including access roads, gage stations, watershed controls, and control measures installed under the Individual Permit. Section 3 contains damage assessments of monitoring wells by the groundwater monitoring groups as established in the Interim Facility-Wide Groundwater Monitoring Plan for Monitoring Year 2014. Section 4 addresses damage and loss of automated samplers. Section 5 addresses sediment sampling needs, and Section 6 is the summary of estimated recovery costs from the significant rain and flooding during September 2013.

  4. Novel flood risk assessment framework for rapid decision making

    Science.gov (United States)

    Valyrakis, Manousos; Koursari, Eftychia; Solley, Mark

    2016-04-01

    The impacts of catastrophic flooding, have significantly increased over the last few decades. This is due to primarily the increased urbanisation in ever-expanding mega-cities as well as due to the intensification both in magnitude and frequency of extreme hydrologic events. Herein a novel conceptual framework is presented that incorporates the use of real-time information to inform and update low dimensionality hydraulic models, to allow for rapid decision making towards preventing loss of life and safeguarding critical infrastructure. In particular, a case study from the recent UK floods in the area of Whitesands (Dumfries), is presented to demonstrate the utility of this approach. It is demonstrated that effectively combining a wealth of readily available qualitative information (such as crowdsourced visual documentation or using live data from sensing techniques), with existing quantitative data, can help appropriately update hydraulic models and reduce modelling uncertainties in future flood risk assessments. This approach is even more useful in cases where hydraulic models are limited, do not exist or were not needed before unpredicted dynamic modifications to the river system took place (for example in the case of reduced or eliminated hydraulic capacity due to blockages). The low computational cost and rapid assessment this framework offers, render it promising for innovating in flood management.

  5. 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.

  6. Flood damage assessment – Literature review and recommended procedure

    DEFF Research Database (Denmark)

    Olesen, Lea; Löwe, Roland; Arnbjerg-Nielsen, Karsten

    The assessment of flood risk is an essential tool in evaluating the potential consequences of a flood. The analysis of the risk can be applied as part of the flood plain management, but can also be used in a cost-benefit analysis, when comparing different adaption strategies. This analysis is the...

  7. Assessment of factors contributing to flood disaster in Ibadan ...

    African Journals Online (AJOL)

    Climate change has brought with it some forms of extreme weather events. One of such is heavy rainfall which often leads to flood. In recent times, flood disaster has been a regular occurrence destroying lives and property. This study was carried out to identify and assess contributing factors to flood disaster in Ibadan ...

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

    OpenAIRE

    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 ris...

  9. A Bayesian Network approach for flash flood risk assessment

    Science.gov (United States)

    Boutkhamouine, Brahim; Roux, Hélène; Pérès, François

    2017-04-01

    influencing variables. Each node of the graph corresponds to a variable and arcs represent the probabilistic dependencies between these variables. Both the quantification of the strength of these probabilistic dependencies and the computation of inferences are based on Bayes' theorem. In order to use BNs for the assessment of the flooding risks, the modelling work is divided into two parts. First, identifying all the factors controlling the flood generation. The qualitative explanation of this issue is then reached by establishing the cause and effect relationships between these factors. These underlying relationships are represented in what we call Conditional Probabilities Tables (CPTs). The next step is to estimate these CPTs using information coming from network of sensors, databases and expertise. By using this basic cognitive structure, we will be able to estimate the magnitude of flood risk in a small geographical area with a homogeneous hydrological system. The second part of our work will be dedicated to the estimation of this risk on the scale of a basin. To do so, we will create a spatio-temporal model able to take in consideration both spatial and temporal variability of all factors involved in the flood generation. Key words: Flash flood forecasting - Uncertainty modelling - flood risk management -Bayesian Networks.

  10. A framework for probabilistic pluvial flood nowcasting for urban areas

    Science.gov (United States)

    Ntegeka, Victor; Murla, Damian; Wang, Lipen; Foresti, Loris; Reyniers, Maarten; Delobbe, Laurent; Van Herk, Kristine; Van Ootegem, Luc; Willems, Patrick

    2016-04-01

    Pluvial flood nowcasting is gaining ground not least because of the advancements in rainfall forecasting schemes. Short-term forecasts and applications have benefited from the availability of such forecasts with high resolution in space (~1km) and time (~5min). In this regard, it is vital to evaluate the potential of nowcasting products for urban inundation applications. One of the most advanced Quantitative Precipitation Forecasting (QPF) techniques is the Short-Term Ensemble Prediction System, which was originally co-developed by the UK Met Office and Australian Bureau of Meteorology. The scheme was further tuned to better estimate extreme and moderate events for the Belgian area (STEPS-BE). Against this backdrop, a probabilistic framework has been developed that consists of: (1) rainfall nowcasts; (2) sewer hydraulic model; (3) flood damage estimation; and (4) urban inundation risk mapping. STEPS-BE forecasts are provided at high resolution (1km/5min) with 20 ensemble members with a lead time of up to 2 hours using a 4 C-band radar composite as input. Forecasts' verification was performed over the cities of Leuven and Ghent and biases were found to be small. The hydraulic model consists of the 1D sewer network and an innovative 'nested' 2D surface model to model 2D urban surface inundations at high resolution. The surface components are categorized into three groups and each group is modelled using triangular meshes at different resolutions; these include streets (3.75 - 15 m2), high flood hazard areas (12.5 - 50 m2) and low flood hazard areas (75 - 300 m2). Functions describing urban flood damage and social consequences were empirically derived based on questionnaires to people in the region that were recently affected by sewer floods. Probabilistic urban flood risk maps were prepared based on spatial interpolation techniques of flood inundation. The method has been implemented and tested for the villages Oostakker and Sint-Amandsberg, which are part of the

  11. Extending flood damage assessment methodology to include ...

    African Journals Online (AJOL)

    Optimal and sustainable flood plain management, including flood control, can only be achieved when the impacts of flood control measures are considered for both the man-made and natural environments, and the sociological aspects are fully considered. Until now, methods/models developed to determine the influences ...

  12. Assessment of vulnerability to extreme flash floods in design storms.

    Science.gov (United States)

    Kim, Eung Seok; Choi, Hyun Il

    2011-07-01

    There has been an increase in the occurrence of sudden local flooding of great volume and short duration caused by heavy or excessive rainfall intensity over a small area, which presents the greatest potential danger threat to the natural environment, human life, public health and property, etc. Such flash floods have rapid runoff and debris flow that rises quickly with little or no advance warning to prevent flood damage. This study develops a flash flood index through the average of the same scale relative severity factors quantifying characteristics of hydrographs generated from a rainfall-runoff model for the long-term observed rainfall data in a small ungauged study basin, and presents regression equations between rainfall characteristics and the flash flood index. The aim of this study is to develop flash flood index-duration-frequency relation curves by combining the rainfall intensity-duration-frequency relation and the flash flood index from probability rainfall data in order to evaluate vulnerability to extreme flash floods in design storms. This study is an initial effort to quantify the flash flood severity of design storms for both existing and planned flood control facilities to cope with residual flood risks due to extreme flash floods that have ocurred frequently in recent years.

  13. A National Assessment of Changes in Flood Exposure in the United States

    Science.gov (United States)

    Lam, N.; Qiang, Y.; Cai, H.; Zou, L.

    2017-12-01

    Analyzing flood exposure and its temporal trend is the first step toward understanding flood risk, flood hazard, and flood vulnerability. This presentation is based on a national, county-based study assessing the changes in population and urban areas in high-risk flood zones from 2001-2011 in the contiguous United States. Satellite land use land cover data, Federal Emergency Management Agency (FEMA)'s 100-year flood maps, and census data were used to extract the proportion of developed (urban) land in flood zones by county in the two time points, and indices of difference were calculated. Local Moran's I statistic was applied to identify hotspots of increase in urban area in flood zones, and geographically weighted regression was used to estimate the population in flood zones from the land cover data. Results show that in 2011, an estimate of about 25.3 million people (8.3% of the total population) lived in the high-risk flood zones. Nationally, the ratio of urban development in flood zones is less than the ratio of land in flood zones, implying that Americans were responsive to flood hazards by avoiding development in flood zones. However, this trend varied from place to place, with coastal counties having less urban development in flood zones than the inland counties. Furthermore, the contrast between coastal and inland counties increased during 2001-2011. Finally, several exceptions from the trend (hotspots) were detected, most notably New York City and Miami where significant increases in urban development in flood zones were found. This assessment provides important baseline information on the spatial patterns of flood exposure and their changes from 2001-2011. The study pinpoints regions that may need further investigations and better policy to reduce the overall flood risks. Methodologically, the study demonstrates that pixelated land cover data can be integrated with other natural and human data to investigate important societal problems. The same

  14. Floods and climate: emerging perspectives for flood risk assessment and management

    DEFF Research Database (Denmark)

    Merz, B.; Aerts, J.; Arnbjerg-Nielsen, Karsten

    2014-01-01

    context of floods. We come to the following conclusions: (1) extending the traditional system boundaries (local catchment, recent decades, hydrological/hydraulic processes) opens up exciting possibilities for better understanding and improved tools for flood risk assessment and management. (2) Statistical......, and this variation may be partially quantifiable and predictable, with the perspective of dynamic, climate-informed flood risk management. (4) Efforts are needed to fully account for factors that contribute to changes in all three risk components (hazard, exposure, vulnerability) and to better understand......Flood estimation and flood management have traditionally been the domain of hydrologists, water resources engineers and statisticians, and disciplinary approaches abound. Dominant views have been shaped; one example is the catchment perspective: floods are formed and influenced by the interaction...

  15. Flood Hazard Assessment for the Savannah River Site

    International Nuclear Information System (INIS)

    Chen, K.F.

    1999-01-01

    'A method was developed to determine the probabilistic flood elevation curves for certain Savannah River Site (SRS) facilities. This paper presents the method used to determine the probabilistic flood elevation curve for F-Area due to runoff from the Upper Three Runs basin. Department of Energy (DOE) Order 420.1, Facility Safety, outlines the requirements for Natural Phenomena Hazard (NPH) mitigation for new and existing DOE facilities. The NPH considered in this paper is flooding. The facility-specific probabilistic flood hazard curve defines as a function of water elevation the annual probability of occurrence or the return period in years. Based on facility-specific probabilistic flood hazard curves and the nature of facility operations (e.g., involving hazardous or radioactive materials), facility managers can design permanent or temporary devices to prevent the propagation of flood on site, and develop emergency preparedness plans to mitigate the consequences of floods.'

  16. Geomorphic Flood Area (GFA): a QGIS tool for a cost-effective delineation of the floodplains

    Science.gov (United States)

    Samela, Caterina; Albano, Raffaele; Sole, Aurelia; Manfreda, Salvatore

    2017-04-01

    Flood Prone Areas using Digital Elevation Models, Journal of Hydrologic Engineering, 16(10), 781-790. Manfreda, S., Nardi, F., Samela, C., Grimaldi, S., Taramasso, A. C., Roth, G., & Sole, A. (2014). Investigation on the Use of Geomorphic Approaches for the Delineation of Flood Prone Areas, Journal of Hydrology, 517, 863-876. Manfreda, S., Samela, C., Gioia, A., Consoli, G., Iacobellis, V., Giuzio, L., & Sole, A. (2015). Flood-prone areas assessment using linear binary classifiers based on flood maps obtained from 1D and 2D hydraulic models. Natural Hazards, Vol. 79 (2), pp 735-754. Samela, C. (2016), 100-year flood susceptibility maps for the continental U.S. derived with a geomorphic method. University of Basilicata. Dataset. Samela, C., Manfreda, S., Paola, F. D., Giugni, M., Sole, A., & Fiorentino, M. (2016). DEM-Based Approaches for the Delineation of Flood-Prone Areas in an Ungauged Basin in Africa. Journal of Hydrologic Engineering, 21(2), 1-10. Samela, C., Troy, T.J., Manfreda, S. (2017). Geomorphic classifiers for flood-prone areas delineation for data-scarce environments, Advances in Water Resources (under review).

  17. Integrated urban flood risk assessment – adapting a multicriteria approach to a city

    Directory of Open Access Journals (Sweden)

    C. Kubal

    2009-11-01

    Full Text Available Flood risk assessment is an essential part of flood risk management. As part of the new EU flood directive it is becoming increasingly more popular in European flood policy. Particularly cities with a high concentration of people and goods are vulnerable to floods. This paper introduces the adaptation of a novel method of multicriteria flood risk assessment, that was recently developed for the more rural Mulde river basin, to a city. The study site is Leipzig, Germany. The "urban" approach includes a specific urban-type set of economic, social and ecological flood risk criteria, which focus on urban issues: population and vulnerable groups, differentiated residential land use classes, areas with social and health care but also ecological indicators such as recreational urban green spaces. These criteria are integrated using a "multicriteria decision rule" based on an additive weighting procedure which is implemented into the software tool FloodCalc urban. Based on different weighting sets we provide evidence of where the most flood-prone areas are located in a city. Furthermore, we can show that with an increasing inundation extent it is both the social and the economic risks that strongly increase.

  18. Accumulation risk assessment for the flooding hazard

    Science.gov (United States)

    Roth, Giorgio; Ghizzoni, Tatiana; Rudari, Roberto

    2010-05-01

    One of the main consequences of the demographic and economic development and of markets and trades globalization is represented by risks cumulus. In most cases, the cumulus of risks intuitively arises from the geographic concentration of a number of vulnerable elements in a single place. For natural events, risks cumulus can be associated, in addition to intensity, also to event's extension. In this case, the magnitude can be such that large areas, that may include many regions or even large portions of different countries, are stroked by single, catastrophic, events. Among natural risks, the impact of the flooding hazard cannot be understated. To cope with, a variety of mitigation actions can be put in place: from the improvement of monitoring and alert systems to the development of hydraulic structures, throughout land use restrictions, civil protection, financial and insurance plans. All of those viable options present social and economic impacts, either positive or negative, whose proper estimate should rely on the assumption of appropriate - present and future - flood risk scenarios. It is therefore necessary to identify proper statistical methodologies, able to describe the multivariate aspects of the involved physical processes and their spatial dependence. In hydrology and meteorology, but also in finance and insurance practice, it has early been recognized that classical statistical theory distributions (e.g., the normal and gamma families) are of restricted use for modeling multivariate spatial data. Recent research efforts have been therefore directed towards developing statistical models capable of describing the forms of asymmetry manifest in data sets. This, in particular, for the quite frequent case of phenomena whose empirical outcome behaves in a non-normal fashion, but still maintains some broad similarity with the multivariate normal distribution. Fruitful approaches were recognized in the use of flexible models, which include the normal

  19. Uncertainty Analysis of A Flood Risk Mapping Procedure Applied In Urban Areas

    Science.gov (United States)

    Krause, J.; Uhrich, S.; Bormann, H.; Diekkrüger, B.

    In the framework of IRMA-Sponge program the presented study was part of the joint research project FRHYMAP (flood risk and hydrological mapping). A simple con- ceptual flooding model (FLOODMAP) has been developed to simulate flooded areas besides rivers within cities. FLOODMAP requires a minimum of input data (digital el- evation model (DEM), river line, water level plain) and parameters and calculates the flood extent as well as the spatial distribution of flood depths. of course the simulated model results are affected by errors and uncertainties. Possible sources of uncertain- ties are the model structure, model parameters and input data. Thus after the model validation (comparison of simulated water to observed extent, taken from airborne pictures) the uncertainty of the essential input data set (digital elevation model) was analysed. Monte Carlo simulations were performed to assess the effect of uncertain- ties concerning the statistics of DEM quality and to derive flooding probabilities from the set of simulations. The questions concerning a minimum resolution of a DEM re- quired for flood simulation and concerning the best aggregation procedure of a given DEM was answered by comparing the results obtained using all available standard GIS aggregation procedures. Seven different aggregation procedures were applied to high resolution DEMs (1-2m) in three cities (Bonn, Cologne, Luxembourg). Basing on this analysis the effect of 'uncertain' DEM data was estimated and compared with other sources of uncertainties. Especially socio-economic information and monetary transfer functions required for a damage risk analysis show a high uncertainty. There- fore this study helps to analyse the weak points of the flood risk and damage risk assessment procedure.

  20. Framework for probabilistic flood risk assessment in an Alpine region

    Science.gov (United States)

    Schneeberger, Klaus; Huttenlau, Matthias; Steinberger, Thomas; Achleitner, Stefan; Stötter, Johann

    2014-05-01

    Flooding is among the natural hazards that regularly cause significant losses to property and human lives. The assessment of flood risk delivers crucial information for all participants involved in flood risk management and especially for local authorities and insurance companies in order to estimate the possible flood losses. Therefore a framework for assessing flood risk has been developed and is introduced with the presented contribution. Flood risk is thereby defined as combination of the probability of flood events and of potential flood damages. The probability of occurrence is described through the spatial and temporal characterisation of flood. The potential flood damages are determined in the course of vulnerability assessment, whereas, the exposure and the vulnerability of the elements at risks are considered. Direct costs caused by flooding with the focus on residential building are analysed. The innovative part of this contribution lies on the development of a framework which takes the probability of flood events and their spatio-temporal characteristic into account. Usually the probability of flooding will be determined by means of recurrence intervals for an entire catchment without any spatial variation. This may lead to a misinterpretation of the flood risk. Within the presented framework the probabilistic flood risk assessment is based on analysis of a large number of spatial correlated flood events. Since the number of historic flood events is relatively small additional events have to be generated synthetically. This temporal extrapolation is realised by means of the method proposed by Heffernan and Tawn (2004). It is used to generate a large number of possible spatial correlated flood events within a larger catchment. The approach is based on the modelling of multivariate extremes considering the spatial dependence structure of flood events. The input for this approach are time series derived from river gauging stations. In a next step the

  1. Flood Hazard Assessment for the Savannah River Site

    International Nuclear Information System (INIS)

    Chen, K.F.

    2000-01-01

    A method was developed to determine the probabilistic flood elevation curves for certain Savannah River Site (SRS) facilities. This paper presents the method used to determine the probabilistic flood elevation curve for F-Area due to runoff from the Upper Three Runs basin. Department of Energy (DOE) Order 420.1, Facility Safety, outlines the requirements for Natural Phenomena Hazard (NPH) mitigation for new and existing DOE facilities. The NPH considered in this paper is flooding. The facility-specific probabilistic flood hazard curve defines as a function of water elevation the annual probability of occurrence or the return period in years. Based on facility-specific probabilistic flood hazard curves and the nature of facility operations (e.g., involving hazardous or radioactive materials), facility managers can design permanent or temporary devices to prevent the propagation of flood on site, and develop emergency preparedness plans to mitigate the consequences of floods. A method was developed to determine the probabilistic flood hazard curves for SRS facilities. The flood hazard curves for the SRS F-Area due to flooding in the Upper Three Runs basin are presented in this paper

  2. 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.

  3. Evaluating extreme flood characteristics of small mountainous basins of the Black Sea coastal area, Northern Caucasus

    Directory of Open Access Journals (Sweden)

    L. S. Lebedeva

    2015-06-01

    Full Text Available The probability of heavy rains and river floods is expected to increase with time in the Northern Caucasus region. Densely populated areas in the valleys of small mountainous watersheds already frequently suffer from catastrophic peak floods caused by intense rains at higher elevations. This study aimed at assessing the flood characteristics of several small basins in the piedmont area of the Caucasus Mountains adjacent to the Black Sea coast including ungauged Cemes River in the Novorossiysk city. The Deterministic-Stochastic Modelling System which consists of hydrological model Hydrograph and stochastic weather generator was applied to evaluate extreme rainfall and runoff characteristics of 1% exceedance probability. Rainfall intensity is shown to play more significant role than its depth in formation of extreme flows within the studied region.

  4. A quantitative flood risk analysis methodology for urban areas with integration of social research data

    Directory of Open Access Journals (Sweden)

    I. Escuder-Bueno

    2012-09-01

    Full Text Available Risk analysis has become a top priority for authorities and stakeholders in many European countries, with the aim of reducing flooding risk, considering the population's needs and improving risk awareness. Within this context, two methodological pieces have been developed in the period 2009–2011 within the SUFRI project (Sustainable Strategies of Urban Flood Risk Management with non-structural measures to cope with the residual risk, 2nd ERA-Net CRUE Funding Initiative. First, the "SUFRI Methodology for pluvial and river flooding risk assessment in urban areas to inform decision-making" provides a comprehensive and quantitative tool for flood risk analysis. Second, the "Methodology for investigation of risk awareness of the population concerned" presents the basis to estimate current risk from a social perspective and identify tendencies in the way floods are understood by citizens. Outcomes of both methods are integrated in this paper with the aim of informing decision making on non-structural protection measures. The results of two case studies are shown to illustrate practical applications of this developed approach. The main advantage of applying the methodology herein presented consists in providing a quantitative estimation of flooding risk before and after investing in non-structural risk mitigation measures. It can be of great interest for decision makers as it provides rational and solid information.

  5. A quantitative flood risk analysis methodology for urban areas with integration of social research data

    Science.gov (United States)

    Escuder-Bueno, I.; Castillo-Rodríguez, J. T.; Zechner, S.; Jöbstl, C.; Perales-Momparler, S.; Petaccia, G.

    2012-09-01

    Risk analysis has become a top priority for authorities and stakeholders in many European countries, with the aim of reducing flooding risk, considering the population's needs and improving risk awareness. Within this context, two methodological pieces have been developed in the period 2009-2011 within the SUFRI project (Sustainable Strategies of Urban Flood Risk Management with non-structural measures to cope with the residual risk, 2nd ERA-Net CRUE Funding Initiative). First, the "SUFRI Methodology for pluvial and river flooding risk assessment in urban areas to inform decision-making" provides a comprehensive and quantitative tool for flood risk analysis. Second, the "Methodology for investigation of risk awareness of the population concerned" presents the basis to estimate current risk from a social perspective and identify tendencies in the way floods are understood by citizens. Outcomes of both methods are integrated in this paper with the aim of informing decision making on non-structural protection measures. The results of two case studies are shown to illustrate practical applications of this developed approach. The main advantage of applying the methodology herein presented consists in providing a quantitative estimation of flooding risk before and after investing in non-structural risk mitigation measures. It can be of great interest for decision makers as it provides rational and solid information.

  6. Assessment on the pedestrian risk during floods based on numerical simulation - A case study in Jinan City

    Science.gov (United States)

    Cheng, T.; Xu, Z.; Hong, S.

    2017-12-01

    Flood disasters frequently attack the urban area in Jinan City during past years, and the city is faced with severe road flooding which greatly threaten pedestrians' safety. Therefore, it is of great significance to investigate the pedestrian risk during floods under specific topographic condition. In this study, a model coupled hydrological and hydrodynamic processes is developed in the study area to simulate the flood routing process on the road for the "7.18" rainstorm and validated with post-disaster damage survey information. The risk of pedestrian is estimated with a flood risk assessment model. The result shows that the coupled model performs well in the rainstorm flood process. On the basis of the simulation result, the areas with extreme risk, medium risk, and mild risk are identified, respectively. Regions with high risk are generally located near the mountain front area with steep slopes. This study will provide scientific support for the flood control and disaster reduction in Jinan City.

  7. Integrated flash flood vulnerability assessment: Insights from East Attica, Greece

    Science.gov (United States)

    Karagiorgos, Konstantinos; Thaler, Thomas; Heiser, Micha; Hübl, Johannes; Fuchs, Sven

    2016-10-01

    In the framework of flood risk assessment, vulnerability is a key concept to assess the susceptibility of elements at risk. Besides the increasing amount of studies on flash floods available, in-depth information on vulnerability in Mediterranean countries was missing so far. Moreover, current approaches in vulnerability research are driven by a divide between social scientists who tend to view vulnerability as representing a set of socio-economic factors, and natural scientists who view vulnerability in terms of the degree of loss to an element at risk. Further, vulnerability studies in response to flash flood processes are rarely answered in the literature. In order to close this gap, this paper implemented an integrated vulnerability approach focusing on residential buildings exposed to flash floods in Greece. In general, both physical and social vulnerability was comparable low, which is interpreted as a result from (a) specific building regulations in Greece as well as general design principles leading to less structural susceptibility of elements at risk exposed, and (b) relatively low economic losses leading to less social vulnerability of citizens exposed. The population show high risk awareness and coping capacity to response to natural hazards event and in the same time the impact of the events are quite low, because of the already high use of local protection measures. The low vulnerability score for East Attica can be attributed especially to the low physical vulnerability and the moderate socio-economic well-being of the area. The consequence is to focus risk management strategies mainly in the reduction of the social vulnerability. By analysing both physical and social vulnerability an attempt was made to bridge the gap between scholars from sciences and humanities, and to integrate the results of the analysis into the broader vulnerability context.

  8. Evolutionary leap in large-scale flood risk assessment needed

    OpenAIRE

    Vorogushyn, Sergiy; Bates, Paul D.; de Bruijn, Karin; Castellarin, Attilio; Kreibich, Heidi; Priest, Sally J.; Schröter, Kai; Bagli, Stefano; Blöschl, Günter; Domeneghetti, Alessio; Gouldby, Ben; Klijn, Frans; Lammersen, Rita; Neal, Jeffrey C.; Ridder, Nina

    2018-01-01

    Current approaches for assessing large-scale flood risks contravene the fundamental principles of the flood risk system functioning because they largely ignore basic interactions and feedbacks between atmosphere, catchments, river-floodplain systems and socio-economic processes. As a consequence, risk analyses are uncertain and might be biased. However, reliable risk estimates are required for prioritizing national investments in flood risk mitigation or for appraisal and management of insura...

  9. Environmental Health Risk Assesement in Flood-prone Area in Tamangapa Sub-District Makassar

    Science.gov (United States)

    Haris, Ibrahim Abdul; Basir, Basir

    2018-05-01

    Environmental health in Indonesia is still caution to concern, poor sanitation in Indonesia is characterized by the high incidence of infectious diseases in society. The society in flood-prone area has a high-risk exposure on the disease based on the environment because they live in disaster-prone area. This research aimed to describe the condition of sanitary facilities and risky behavior on public health in flood-prone areas in Manggala district particularly in Tamangapa sub-district of Makassar. This reserach uses an observation method with a descriptive approach. The data is processed by using SPSS and Arc View GIS applications. Environmental risk category is determined by the approach of Environmental Health Risk Assessment (EHRA). The results showed that the flood-prone area in RT 04 RW 06 was included in very high-risk category at 229 with an index value of environmental health risks 212-229. Meanwhile, RT 04 RW 05 was in the category of low risk in the amount of 155 with an index of 155-173. Environmental health hazards identified in Tamangapa flood-prone areas sub-district includes domestic sources of clean water, domestic wastewater, and household garbage.

  10. Flood hazard assessment for the Savannah River Site

    International Nuclear Information System (INIS)

    Chen, K.F.

    2000-01-01

    A method was developed to determine the probabilistic flood elevation curves for certain Savannah River Site (SRS) facilities. This paper presents the method used to determine the probabilistic flood elevation curve for F-Area due to runoff from the Upper Three Runs basin. Department of Energy (DOE) Order 420.1, Facility Safety, outlines the requirements for Natural Phenomena Hazard (NPH) mitigation for new and existing DOE facilities. The NPH considered in this paper is flooding. The facility-specific probabilistic flood hazard curve defines as a function of water elevation the annual probability of occurrence or the return period in years. Based on facility-specific probabilistic flood hazard curves and the nature of facility operations (e.g., involving hazardous or radioactive materials), facility managers can design permanent or temporary devices to prevent the propagation of flood on site, and develop emergency preparedness plans to mitigate the consequences of floods. The flood hazard curves for the SRS F-Area due to flooding in the Upper Three Runs basin are presented in this paper

  11. Integrating adaptive behaviour in large-scale flood risk assessments: an Agent-Based Modelling approach

    Science.gov (United States)

    Haer, Toon; Aerts, Jeroen

    2015-04-01

    Between 1998 and 2009, Europe suffered over 213 major damaging floods, causing 1126 deaths, displacing around half a million people. In this period, floods caused at least 52 billion euro in insured economic losses making floods the most costly natural hazard faced in Europe. In many low-lying areas, the main strategy to cope with floods is to reduce the risk of the hazard through flood defence structures, like dikes and levees. However, it is suggested that part of the responsibility for flood protection needs to shift to households and businesses in areas at risk, and that governments and insurers can effectively stimulate the implementation of individual protective measures. However, adaptive behaviour towards flood risk reduction and the interaction between the government, insurers, and individuals has hardly been studied in large-scale flood risk assessments. In this study, an European Agent-Based Model is developed including agent representatives for the administrative stakeholders of European Member states, insurers and reinsurers markets, and individuals following complex behaviour models. The Agent-Based Modelling approach allows for an in-depth analysis of the interaction between heterogeneous autonomous agents and the resulting (non-)adaptive behaviour. Existing flood damage models are part of the European Agent-Based Model to allow for a dynamic response of both the agents and the environment to changing flood risk and protective efforts. By following an Agent-Based Modelling approach this study is a first contribution to overcome the limitations of traditional large-scale flood risk models in which the influence of individual adaptive behaviour towards flood risk reduction is often lacking.

  12. Impact of modelling scale on probabilistic flood risk assessment: the Malawi case

    Directory of Open Access Journals (Sweden)

    Rudari Roberto

    2016-01-01

    Full Text Available In the early months of 2015, destructive floods hit Malawi, causing deaths and economic losses. Flood risk assessment outcomes can be used to increase scientific-supported awareness of risk. The recent increase in availability of high resolution data such as TanDEM-X at 12m resolution makes possible the use of detailed physical based flood hazard models in risk assessment. Nonetheless the scale of hazard modelling still remains an issue, which requires a compromise between level of detail and computational efforts. This work presents two different approaches on hazard modelling. Both methods rely on 32-years of numeric weather re-analysis and rainfall-runoff transformation through a fully distributed WFLOW-type hydrological model. The first method, applied at national scale, uses fast post-processing routines, which estimate flood water depth at a resolution of about 1×1km. The second method applies a full 2D hydraulic model to propagate water discharge into the flood plains and best suites for small areas where assets are concentrated. At the 12m resolution, three hot spots with a model area of approximately 10×10 km are analysed. Flood hazard maps obtained with both approaches are combined with flood impact models at the same resolution to generate indicators for flood risk. A quantitative comparison of the two approaches is presented in order to show the effects of modelling scale on both hazard and impact losses.

  13. 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

  14. The effect of a disastrous flood on the quality of life in Dongting lake area in China.

    Science.gov (United States)

    Tan, H Z; Luo, Y J; Wen, S W; Liu, A Z; Li, S Q; Yang, T B; Sun, Z Q

    2004-01-01

    We carried out an epidemiological study to assess the impact of flood on the quality of life (QOL) of residents in the affected areas in China. We used a natural experiment approach, randomly selected 494 adults from 18 villages, which suffered from flooding as a result of embankments collapsing, 473 adults from 16 villages, which suffered from, soaked flood, and 773 adults from 11 villages without flood (control group). We used the Generic QOL Inventory-74 (GQOLI-74), social support scale, and questionnaires to assess the QOL of all study participants. The QOL was significantly poorer in soaked group (58.4) and (especially) in collapsed group (55.1) than in control group (59.5, pintrovert personality, and residents with adverse life-events, whereas social support and extrovert personalities offset the negative impact of flood on QOL.

  15. Flood damage curves for consistent global risk assessments

    Science.gov (United States)

    de Moel, Hans; Huizinga, Jan; Szewczyk, Wojtek

    2016-04-01

    Assessing potential damage of flood events is an important component in flood risk management. Determining direct flood damage is commonly done using depth-damage curves, which denote the flood damage that would occur at specific water depths per asset or land-use class. Many countries around the world have developed flood damage models using such curves which are based on analysis of past flood events and/or on expert judgement. However, such damage curves are not available for all regions, which hampers damage assessments in those regions. Moreover, due to different methodologies employed for various damage models in different countries, damage assessments cannot be directly compared with each other, obstructing also supra-national flood damage assessments. To address these problems, a globally consistent dataset of depth-damage curves has been developed. This dataset contains damage curves depicting percent of damage as a function of water depth as well as maximum damage values for a variety of assets and land use classes (i.e. residential, commercial, agriculture). Based on an extensive literature survey concave damage curves have been developed for each continent, while differentiation in flood damage between countries is established by determining maximum damage values at the country scale. These maximum damage values are based on construction cost surveys from multinational construction companies, which provide a coherent set of detailed building cost data across dozens of countries. A consistent set of maximum flood damage values for all countries was computed using statistical regressions with socio-economic World Development Indicators from the World Bank. Further, based on insights from the literature survey, guidance is also given on how the damage curves and maximum damage values can be adjusted for specific local circumstances, such as urban vs. rural locations, use of specific building material, etc. This dataset can be used for consistent supra

  16. Integral assessment of floodplains as a basis for spatially-explicit flood loss forecasts

    Science.gov (United States)

    Zischg, Andreas Paul; Mosimann, Markus; Weingartner, Rolf

    2016-04-01

    flood scenario, the resulting number of affected residents, houses and therefore the losses are computed. This integral assessment leads to a hydro-economical characterisation of each floodplain. Based on that, a transfer function between discharge forecast and damages can be elaborated. This transfer function describes the relationship between predicted peak discharge, flood volume and the number of exposed houses, residents and the related losses. It also can be used to downscale the regional discharge forecast to a local level loss forecast. In addition, a dynamic map delimiting the probable flooded areas on the basis of the forecasted discharge can be prepared. The predicted losses and the delimited flooded areas provide a complementary information for assessing the need of preventive measures on one hand on the long-term timescale and on the other hand 6h-24h in advance of a predicted flood. To conclude, we can state that the transfer function offers the possibility for an integral assessment of floodplains as a basis for spatially-explicit flood loss forecasts. The procedure has been developed and tested in the alpine and pre-alpine environment of the Aare river catchment upstream of Bern, Switzerland.

  17. Flood damage in Italy: towards an assessment model of reconstruction costs

    Science.gov (United States)

    Sterlacchini, Simone; Zazzeri, Marco; Genovese, Elisabetta; Modica, Marco; Zoboli, Roberto

    2016-04-01

    Recent decades in Italy have seen a very rapid expansion of urbanisation in terms of physical assets, while demographics have remained stable. Both the characteristics of Italian soil and anthropic development, along with repeated global climatic stress, have made the country vulnerable to floods, the intensity of which is increasingly alarming. The combination of these trends will contribute to large financial losses due to property damage in the absence of specific mitigation strategies. The present study focuses on the province of Sondrio in Northern Italy (area of about 3,200 km²), which is home to more than 180,000 inhabitants and the population is growing slightly. It is clearly a hot spot for flood exposure, as it is primarily a mountainous area where floods and flash floods hit frequently. The model we use for assessing potential flood damage determines risk scenarios by overlaying flood hazard maps and economic asset data. In Italy, hazard maps are provided by Regional Authorities through the Hydrogeological System Management Plan (PAI) based on EU Flood Directive guidelines. The PAI in the study area includes both the large plain and the secondary river system and considers three hazard scenarios of Low, Medium and High Frequency associated with return periods of 20, 200 and 500 years and related water levels. By an overlay of PAI maps and residential areas, visualized on a GIS, we determine which existing built-up areas are at risk for flood according to each scenario. Then we investigate the value of physical assets potentially affected by floods in terms of market values, using the database of the Italian Property Market Observatory (OMI), and in terms of reconstruction costs, by considering synthetic cost indexes of predominant building types (from census information) and PAI water height. This study illustrates a methodology to assess flood damage in urban settlements and aims to determine general guidelines that can be extended throughout Italy

  18. Flash-flood potential assessment and mapping by integrating the ...

    Indian Academy of Sciences (India)

    Romulus Costache

    2017-06-16

    Jun 16, 2017 ... torrential phenomena considered for the study (training area) and for the results' testing (validating ... Service (USA). At that ... to improve the quality of flash-flood forecasts. ...... offers the possibility to obtain more credible and.

  19. Vulnerability assessment including tangible and intangible components in the index composition: An Amazon case study of flooding and flash flooding.

    Science.gov (United States)

    Andrade, Milena Marília Nogueira de; Szlafsztein, Claudio Fabian

    2018-07-15

    The vulnerability of cities and communities in the Amazon to flooding and flash flooding is increasing. The effects of extreme events on populations vary across landscapes, causing vulnerability to differ spatially. Traditional vulnerability studies in Brazil and across the world have used the vulnerability index for the country and, more recently, municipality scales. The vulnerability dimensions are exposure, sensitivity, and adaptive capacity. For each of these dimensions, there is a group of indicators that constitutes a vulnerability index using quantitative data. Several vulnerability assessments have used sensitivity and exposure analyses and, recently, adaptive capacity has been considered. The Geographical Information Systems (GIS) analysis allows spatial regional modeling using quantitative vulnerability indicators. This paper presents a local-scale vulnerability assessment in an urban Amazonian area, Santarém City, using interdisciplinary methods. Data for exposure and sensitivity were gathered by remote sensing and census data, respectively. However, adaptive capacity refers to local capacities, whether infrastructural or not, and the latter were gathered by qualitative participatory methods. For the mixed data used to study adaptive capacity, we consider tangible components for countable infrastructure that can cope with hazards, and intangible components that reflect social activities based on risk perceptions and collective action. The results indicate that over 80% of the area is highly or moderately vulnerable to flooding and flash flooding. Exposure and adaptive capacity were determinants of the results. Lower values of adaptive capacity play a significant role in vulnerability enhancement. Copyright © 2018 Elsevier B.V. All rights reserved.

  20. Quantification of uncertainty in flood risk assessment for flood protection planning: a Bayesian approach

    Science.gov (United States)

    Dittes, Beatrice; Špačková, Olga; Ebrahimian, Negin; Kaiser, Maria; Rieger, Wolfgang; Disse, Markus; Straub, Daniel

    2017-04-01

    Flood risk estimates are subject to significant uncertainties, e.g. due to limited records of historic flood events, uncertainty in flood modeling, uncertain impact of climate change or uncertainty in the exposure and loss estimates. In traditional design of flood protection systems, these uncertainties are typically just accounted for implicitly, based on engineering judgment. In the AdaptRisk project, we develop a fully quantitative framework for planning of flood protection systems under current and future uncertainties using quantitative pre-posterior Bayesian decision analysis. In this contribution, we focus on the quantification of the uncertainties and study their relative influence on the flood risk estimate and on the planning of flood protection systems. The following uncertainty components are included using a Bayesian approach: 1) inherent and statistical (i.e. limited record length) uncertainty; 2) climate uncertainty that can be learned from an ensemble of GCM-RCM models; 3) estimates of climate uncertainty components not covered in 2), such as bias correction, incomplete ensemble, local specifics not captured by the GCM-RCM models; 4) uncertainty in the inundation modelling; 5) uncertainty in damage estimation. We also investigate how these uncertainties are possibly reduced in the future when new evidence - such as new climate models, observed extreme events, and socio-economic data - becomes available. Finally, we look into how this new evidence influences the risk assessment and effectivity of flood protection systems. We demonstrate our methodology for a pre-alpine catchment in southern Germany: the Mangfall catchment in Bavaria that includes the city of Rosenheim, which suffered significant losses during the 2013 flood event.

  1. Swift delineation of flood-prone areas over large European regions

    Science.gov (United States)

    Tavares da Costa, Ricardo; Castellarin, Attilio; Manfreda, Salvatore; Samela, Caterina; Domeneghetti, Alessio; Mazzoli, Paolo; Luzzi, Valerio; Bagli, Stefano

    2017-04-01

    According to the European Environment Agency (EEA Report No 1/2016), a significant share of the European population is estimated to be living on or near a floodplain, with Italy having the highest population density in flood-prone areas among the countries analysed. This tendency, tied with event frequency and magnitude (e.g.: the 24/11/2016 floods in Italy) and the fact that river floods may occur at large scales and at a transboundary level, where data is often sparse, presents a challenge in flood-risk management. The availability of consistent flood hazard and risk maps during prevention, preparedness, response and recovery phases are a valuable and important step forward in improving the effectiveness, efficiency and robustness of evidence-based decision making. The present work aims at testing and discussing the usefulness of pattern recognition techniques based on geomorphologic indices (Manfreda et al., J. Hydrol. Eng., 2011, Degiorgis et al., J Hydrol., 2012, Samela et al., J. Hydrol. Eng., 2015) for the simplified mapping of river flood-prone areas at large scales. The techniques are applied to 25m Digital Elevation Models (DEM) of the Danube, Po and Severn river watersheds, obtained from the Copernicus data and information funded by the European Union - EU-DEM layers. Results are compared to the Pan-European flood hazard maps derived by Alfieri et al. (Hydrol. Proc., 2013) using a set of distributed hydrological (LISFLOOD, van der Knijff et al., Int. J. Geogr. Inf. Sci., 2010, employed within the European Flood Awareness System, www.efas.eu) and hydraulic models (LISFLOOD-FP, Bates and De Roo, J. Hydrol., 2000). Our study presents different calibration and cross-validation exercises of the DEM-based mapping algorithms to assess to which extent, and with which accuracy, they can be reproduced over different regions of Europe. This work is being developed under the System-Risk project (www.system-risk.eu) that received funding from the European Union

  2. Internal Flooding Probabilistic Safety Assessment of an OPR-1000 Plant during Low Power and Shutdown Operation

    International Nuclear Information System (INIS)

    Lee, Yoon Hwan; Park, Jin Hee; Lim, Ho Gon

    2016-01-01

    In 2009, the electric power research institute (EPRI) published a guideline for the development of IF-PRA that addresses the requirements of the ASME/ANS RASa-2009 PRA consensus standard. The EPRI guideline delineates a level of detail and assessment complexity that has been significantly increased with respect to the guidance for IF assessment performed for the individual plant examination (IPE) to address Generic Letter 88- 20. The main differences include: A more systematic approach to the definition of flood area. The identification, screening and analysis of flooding sources and scenarios. The calculation of the initiating-event frequency (IEF) based on the actual length and characteristics of the piping. The inclusion of spatial effects such as spray from pipe leaks. The specific documentation associated with the plant walkdowns. Among these differences, this research focused on the third and fourth items when performing the internal flooding PSA. This is done by identifying the pipe and fluid characteristics, assessing the pipe pressure, characterizing the pipe (i.e., pipe diameter, length, etc.) and determining the pressure boundary failure frequency. The results were summed for the various piping systems within a given flood area to arrive at an overall internal flood initiating frequency for a given flood mode (i.e., spray, general flood, or major flood) for that particular area by each POS (Plant Operational State). In this initiating event frequency evaluations, the POS duration time is especially considered to get the real values for LPSD state. Characterizations of spray scenarios were evaluated to determine their impact on plant risk caused by internal flooding events.

  3. FLOOD RISK ASSESSMENT IN RIVER TIMIS BASIN - THE CARANSEBES - LUGOJ SECTOR- USING GIS TECHNIQUE

    Directory of Open Access Journals (Sweden)

    MIHAI VALENTIN HERBEI

    2012-11-01

    Full Text Available Flood risk assessment in Timis River basin - the Caransebes -Lugoj sector- using GIS technique. Over time freshets, thus floods constituted and constitute a particularly important issue that requires attention. In many cases, flood damages are extensive to the environment, to the economy and also socially. The purpose of this paper is to identify flood-prone areas between Caransebes and Lugoj, land that is part of the Timis river basin. This paper is based on a theoretical model in which we considered the building elements of the flood produced on the Timis river in April 2005 (levels and flows. to represent the zones flood – prone, we used the numerical model of the terrain, created for the abovementioned area. On this model , according to levels measured at hydrometric stations, were defined those flood prone areas. The Timis river hydrographic basin includes a varied terrain (mountains, hills and plains, with pronounced differences in altitude and massiveness, resulting from tectonic movements that have affected the region, this fact has affected water flow processes, both directly through fragmentation and slope, and indirectly, by creating the vertical climate, vegetation and soils zones. Using GIS technology to study hydrological phenomena and their impact on the geographic area are of particular importance due to the complexity of these techniques, which enables detailed analysis and analytical precision as well as an increased speed of the analysis. Creating theoretical models that give scale to the hydrological phenomena, in this case representing the flood areas, is of great practical importance because based on these models the areas can be defined and viewed, having the possibility of taking measures to prevent environmental effects on the natural and / or anthropogenic environment. In the studied area review of the flood of 2005, were represented flood areas, therefore, according with the researches, several villages, located in

  4. How useful are Swiss flood insurance data for flood vulnerability assessments?

    Science.gov (United States)

    Röthlisberger, Veronika; Bernet, Daniel; Zischg, Andreas; Keiler, Margreth

    2015-04-01

    vulnerability and resilience assessments. For instance, the collation of insurance loss data with event documentations containing information on flood intensity allows to develop damage curves. Flood damage curves are fundamental for many risk analysis methodologies but to date only few are published and the spatial and temporal scope of their applicability is subject of discussion. Another possibility of using insurance data lies in the field of assessment exposure, where the analysis of comprehensive insurance portfolio data can improve the understanding of the physical but also the socio-economical vulnerability of a society. The poster spotlights key opportunities and challenges scientists are facing when using insurance data for flood vulnerability assessments.

  5. Upstream Structural Management Measures for an Urban Area Flooding in Turkey and their Consequences on Flood Risk Management

    Science.gov (United States)

    Akyurek, Z.; Bozoglu, B.; Girayhan, T.

    2015-12-01

    Flooding has the potential to cause significant impacts to economic activities as well as to disrupt or displace populations. Changing climate regimes such as extreme precipitation events increase flood vulnerability and put additional stresses on infrastructure. In this study the flood modelling in an urbanized area, namely Samsun-Terme in Blacksea region of Turkey is done. MIKE21 with flexible grid is used in 2- dimensional shallow water flow modelling. 1/1000 scaled maps with the buildings for the urbanized area and 1/5000 scaled maps for the rural parts are used to obtain DTM needed in the flood modelling. The bathymetry of the river is obtained from additional surveys. The main river passing through the urbanized area has a capacity of Q5 according to the design discharge obtained by simple ungauged discharge estimation depending on catchment area only. The effects of the available structures like bridges across the river on the flooding are presented. The upstream structural measures are studied on scenario basis. Four sub-catchments of Terme River are considered as contributing the downstream flooding. The existing circumstance of the Terme River states that the meanders of the river have a major effect on the flood situation and lead to approximately 35% reduction in the peak discharge between upstream and downstream of the river. It is observed that if the flow from the upstream catchments can be retarded through a detention pond constructed in at least two of the upstream catchments, estimated Q100 flood can be conveyed by the river without overtopping from the river channel. The operation of the upstream detention ponds and the scenarios to convey Q500 without causing flooding are also presented. Structural management measures to address changes in flood characteristics in water management planning are discussed. Flood risk is obtained by using the flood hazard maps and water depth-damage functions plotted for a variety of building types and occupancies

  6. A Computational Framework for Flood Risk Assessment in The Netherlands

    Directory of Open Access Journals (Sweden)

    A.A. Markus

    2010-01-01

    Full Text Available The safety of dikes in The Netherlands, located in the delta of the rivers Rhine, Meuse and Scheldt, has been the subject of debate for more than ten years. The safety (or flood risk of a particular area may depend on the safety of other areas. This is referred to as effects of river system behaviour on flood risk (quantified as the estimated number of casualties and economic damage. A computational framework was developed to assess these effects. It consists of several components that are loosely coupled via data files and Tcl scripts to manage the individual programs and keep track of the state of the computations. The computations involved are lengthy (days or even weeks on a Linux cluster, which makes the framework currently more suitable for planning and design than for real-time operation. While the framework was constructed ad hoc, it can also be viewed more formally as a tuplespace Realising this makes it possible to adopt the philosophy for other similar frameworks.

  7. 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%.

  8. STUDY REGARDING DELINEATION OF FLOOD HAZARD ZONES IN THE HYDROGRAPHIC BASIN OF THE SOMEŞ RIVER, BORDER AREA

    Directory of Open Access Journals (Sweden)

    STOICA F.

    2014-03-01

    Full Text Available The hydrological studies will provide the characteristic parameters for the floods occurred for the calculus discharges with overflow probabilities of 0,1%; 1%, 5%, 10%. The hydrologic and hydraulic models will be made by using the hydro-meteorological data base and the topographical measurements on site; them calibration will be done according to the records of the historical floods. The studies on the hydrologic and hydraulic models will be necessary for the establishment of the carrying capacity of the riverbeds, for the delimitation of the flood plains and for the detection of the transit discharges at the hydro-technical installations, but also for the establishment of the parameters needed for the structural measures’ projects. These will be based on the 1D and 2D unstable hydro-dynamic models. Therefore, the users would be able to assess the proposed measures and the impact over the river’s system; of course with the potential combination of the 1D and 2D. The main objectives followed by the project are: • identification of the river basins or river sub-basins with flood risks; • regionalization of the flood hazard; • presentation of the main flash floods occurred during the last 30 years, which induced floods; • assessment of the consequences of eventual flood over the population, properties and environment; • the establishment of the protection degree, accepted for the human settlements, for the economic and social objectives, for the farm areas, etc.;

  9. What are people thinking about floods? A study in two Mediterranean areas: Costa Brava, Spain and Talcahuano City, Chile

    Science.gov (United States)

    Lara, A.; Ribas, A.; Cifuentes, L. A.

    2013-05-01

    Mediterranean areas are not immune to flood problems. The Spanish Mediterranean coast is a reflection of this, where flooding continues to be the greatest natural hazard with negative effects on the territory. The urbanization of coastal watersheds, very pronounced in the last 15 years, has led to the creation of authentic urban continuums in the seafront and the appearance of residential developments therein. The municipalities of Costa Brava, in the province of Girona, are an example of this dynamic of the increasing risk, exposure, and impact of floods. In Chile, floods are considered one of the main natural hazards, especially in the province of Concepcion. One of the most important cities of this area is Talcahuano, which has suffered continual flood episodes during recent years. Flood episodes could yet increase in the future due to the high frequency of extraordinary atmospheric events and a higher exposure to flood risk created by the development of intensive urbanization processes. However, after the February 27th 8.8 degrees earthquake (Richter scale) that affected the center-south of Chile and originated the tsunami which flooded a large percentage of the residential area and military base of the city of Talcahuano, the risk, vulnerability, resilience and copy capacity concepts changed. This research looks at the social perception and social knowledge of Mediterranean residents affected and unaffected by floods, emphasizing which is their risk, vulnerability, resilience and copy capacity concept and what kind of measures they proposed to reduce their flood vulnerability. The end objective of this research is to become a framework for future local flood policies and a tool that could be reviewed by specialists in other regions that might be affected by this hazard. This social assessment has been carried out through surveys of residents in Costa Brava and Talcahuano whose endogenous and exogenous characteristics have been significant in explaining their

  10. Examining the Capability of Supervised Machine Learning Classifiers in Extracting Flooded Areas from Landsat TM Imagery: A Case Study from a Mediterranean Flood

    Directory of Open Access Journals (Sweden)

    Gareth Ireland

    2015-03-01

    Full Text Available This study explored the capability of Support Vector Machines (SVMs and regularised kernel Fisher’s discriminant analysis (rkFDA machine learning supervised classifiers in extracting flooded area from optical Landsat TM imagery. The ability of both techniques was evaluated using a case study of a riverine flood event in 2010 in a heterogeneous Mediterranean region, for which TM imagery acquired shortly after the flood event was available. For the two classifiers, both linear and non-linear (kernel versions were utilised in their implementation. The ability of the different classifiers to map the flooded area extent was assessed on the basis of classification accuracy assessment metrics. Results showed that rkFDA outperformed SVMs in terms of accurate flooded pixels detection, also producing fewer missed detections of the flooded area. Yet, SVMs showed less false flooded area detections. Overall, the non-linear rkFDA classification method was the more accurate of the two techniques (OA = 96.23%, K = 0.877. Both methods outperformed the standard Normalized Difference Water Index (NDWI thresholding (OA = 94.63, K = 0.818 by roughly 0.06 K points. Although overall accuracy results for the rkFDA and SVMs classifications only showed a somewhat minor improvement on the overall accuracy exhibited by the NDWI thresholding, notably both classifiers considerably outperformed the thresholding algorithm in other specific accuracy measures (e.g. producer accuracy for the “not flooded” class was ~10.5% less accurate for the NDWI thresholding algorithm in comparison to the classifiers, and average per-class accuracy was ~5% less accurate than the machine learning models. This study provides evidence of the successful application of supervised machine learning for classifying flooded areas in Landsat imagery, where few studies so far exist in this direction. Considering that Landsat data is open access and has global coverage, the results of this study

  11. When nature frowns: A comprehensive impact assessment of the 2012 Babessi floods on people’s livelihoods in rural Cameroon

    Directory of Open Access Journals (Sweden)

    Roland A. Balgah

    2015-11-01

    Full Text Available Floods are the most common natural disasters worldwide. Much of the growing literature on the impact of floods, especially in developed countries, and to a lesser extent in rural areas of developing countries, concentrates on economic rather than a comprehensive assessment of combined effects on people’s livelihoods. Holistic floods impact assessments are often done long after the shock, raising problems of data reliability following long recall periods, although post-disaster needs assessments when carried out earlier can facilitate appropriate disaster recovery, relief and reconstruction activities. We applied the sustainable livelihoods framework as a comprehensive approach to assess the impacts of the Babessi floods in 2012 on livelihoods in rural (north western region of Cameroon 6 weeks after the floods. Using a structured questionnaire, data was collected from victims before and after the floods, using recall methods. A matched sample of nonvictims randomly selected from the same village as the victims was used to assess vulnerability to the floods by household type. Floods were found to have serious economic, social, human and food security impacts on victims. Both government and nongovernmental support were jointly crucial for household recovery. Comparatively observed high levels of recovery were attributed to the low loss of human lives. The article concludes with the need for comprehensive approaches to floods impact assessments. The need for combining formal and informal instruments in post-disaster management in rural areas is also emphasised.

  12. Development of method for evaluating estimated inundation area by using river flood analysis based on multiple flood scenarios

    Science.gov (United States)

    Ono, T.; Takahashi, T.

    2017-12-01

    Non-structural mitigation measures such as flood hazard map based on estimated inundation area have been more important because heavy rains exceeding the design rainfall frequently occur in recent years. However, conventional method may lead to an underestimation of the area because assumed locations of dike breach in river flood analysis are limited to the cases exceeding the high-water level. The objective of this study is to consider the uncertainty of estimated inundation area with difference of the location of dike breach in river flood analysis. This study proposed multiple flood scenarios which can set automatically multiple locations of dike breach in river flood analysis. The major premise of adopting this method is not to be able to predict the location of dike breach correctly. The proposed method utilized interval of dike breach which is distance of dike breaches placed next to each other. That is, multiple locations of dike breach were set every interval of dike breach. The 2D shallow water equations was adopted as the governing equation of river flood analysis, and the leap-frog scheme with staggered grid was used. The river flood analysis was verified by applying for the 2015 Kinugawa river flooding, and the proposed multiple flood scenarios was applied for the Akutagawa river in Takatsuki city. As the result of computation in the Akutagawa river, a comparison with each computed maximum inundation depth of dike breaches placed next to each other proved that the proposed method enabled to prevent underestimation of estimated inundation area. Further, the analyses on spatial distribution of inundation class and maximum inundation depth in each of the measurement points also proved that the optimum interval of dike breach which can evaluate the maximum inundation area using the minimum assumed locations of dike breach. In brief, this study found the optimum interval of dike breach in the Akutagawa river, which enabled estimated maximum inundation area

  13. Floods

    Science.gov (United States)

    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 ...

  14. Assessing surface water flood risk and management strategies under future climate change: Insights from an Agent-Based Model.

    Science.gov (United States)

    Jenkins, K; Surminski, S; Hall, J; Crick, F

    2017-10-01

    Climate change and increasing urbanization are projected to result in an increase in surface water flooding and consequential damages in the future. In this paper, we present insights from a novel Agent Based Model (ABM), applied to a London case study of surface water flood risk, designed to assess the interplay between different adaptation options; how risk reduction could be achieved by homeowners and government; and the role of flood insurance and the new flood insurance pool, Flood Re, in the context of climate change. The analysis highlights that while combined investment in property-level flood protection and sustainable urban drainage systems reduce surface water flood risk, the benefits can be outweighed by continued development in high risk areas and the effects of climate change. In our simulations, Flood Re is beneficial in its function to provide affordable insurance, even under climate change. However, the scheme does face increasing financial pressure due to rising surface water flood damages. If the intended transition to risk-based pricing is to take place then a determined and coordinated strategy will be needed to manage flood risk, which utilises insurance incentives, limits new development, and supports resilience measures. Our modelling approach and findings are highly relevant for the ongoing regulatory and political approval process for Flood Re as well as for wider discussions on the potential of insurance schemes to incentivise flood risk management and climate adaptation in the UK and internationally. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Assessment of Hyporheic Zone, Flood-Plain, Soil-Gas, Soil, and Surface-Water Contamination at the McCoys Creek Chemical Training Area, Fort Gordon, Georgia, 2009-2010

    Science.gov (United States)

    Guimaraes, Wladmir B.; Falls, W. Fred; Caldwell, Andral W.; Ratliff, W. Hagan; Wellborn, John B.; Landmeyer, James E.

    2011-01-01

    The U.S. Geological Survey, in cooperation with the U.S. Department of the Army Environmental and Natural Resources Management Office of the U.S. Army Signal Center and Fort Gordon, Georgia, assessed the hyporheic zone, flood plain, soil gas, soil, and surface water for contaminants at the McCoys Creek Chemical Training Area (MCTA) at Fort Gordon, from October 2009 to September 2010. The assessment included the detection of organic contaminants in the hyporheic zone, flood plain, soil gas, and surface water. In addition, the organic contaminant assessment included the analysis of organic compounds classified as explosives and chemical agents in selected areas. Inorganic contaminants were assessed in soil and surface-water samples. The assessment was conducted to provide environmental contamination data to the U.S. Army at Fort Gordon pursuant to requirements of the Resource Conservation and Recovery Act Part B Hazardous Waste Permit process. Ten passive samplers were deployed in the hyporheic zone and flood plain, and total petroleum hydrocarbons (TPH) and octane were detected above the method detection level in every sampler. Other organic compounds detected above the method detection level in the hyporheic zone and flood-plain samplers were trichloroethylene, and cis- and trans- 1, 2-dichloroethylene. One trip blank detected TPH below the method detection level but above the nondetection level. The concentrations of TPH in the samplers were many times greater than the concentrations detected in the blank; therefore, all other TPH concentrations detected are considered to represent environmental conditions. Seventy-one soil-gas samplers were deployed in a grid pattern across the MCTA. Three trip blanks and three method blanks were used and not deployed, and TPH was detected above the method detection level in two trip blanks and one method blank. Detection of TPH was observed at all 71 samplers, but because TPH was detected in the trip and method blanks, TPH was

  16. Impacts of dyke development in flood prone areas in the Vietnamese Mekong Delta to downstream flood hazard

    Science.gov (United States)

    Khanh Triet Nguyen, Van; Dung Nguyen, Viet; Fujii, Hideto; Kummu, Matti; Merz, Bruno; Apel, Heiko

    2016-04-01

    The Vietnamese Mekong Delta (VMD) plays an important role in food security and socio-economic development of the country. Being a low-lying coastal region, the VMD is particularly susceptible to both riverine and tidal floods, which provide, on (the) one hand, the basis for the rich agricultural production and the livelihood of the people, but on the other hand pose a considerable hazard depending on the severity of the floods. But despite of potentially hazardous flood, the area remain active as a rice granary due to its nutrient-rich soils and sediment input, and dense waterways, canals and the long standing experience of the population living with floods. In response to both farmers' requests and governmental plans, the construction of flood protection infrastructure in the delta progressed rapidly in the last twenty years, notably at areas prone to deep flooding, i.e. the Plain of Reeds (PoR) and Long Xuyen Quadrangle (LXQ). Triple rice cropping becomes possible in farmlands enclosed by "full-dykes", i.e. dykes strong and high enough to prevent flooding of the flood plains for most of the floods. In these protected flood plains rice can be grown even during the peak flood period (September to November). However, little is known about the possibly (and already alleged) negative impacts of this fully flood protection measure to downstream areas. This study aims at quantifying how the flood regime in the lower part of the VMD (e.g. Can Tho, My Thuan, …) has been changed in the last 2 recent "big flood" events of 2000 and 2011 due to the construction of the full-dyke system in the upper part. First, an evaluation of 35 years of daily water level data was performed in order to detect trends at key gauging stations: Kratie: upper boundary of the Delta, Tan Chau and Chau Doc: areas with full-dyke construction, Can Tho and My Thuan: downstream. Results from the Mann-Kendall (MK) test show a decreasing trend of the annual maximum water level at 3 stations Kratie, Tan

  17. 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.

  18. Colombia Mi Pronostico Flood Application: Updating and Improving the Mi Pronostico Flood Web Application to Include an Assessment of Flood Risk

    Science.gov (United States)

    Rushley, Stephanie; Carter, Matthew; Chiou, Charles; Farmer, Richard; Haywood, Kevin; Pototzky, Anthony, Jr.; White, Adam; Winker, Daniel

    2014-01-01

    Colombia is a country with highly variable terrain, from the Andes Mountains to plains and coastal areas, many of these areas are prone to flooding disasters. To identify these risk areas NASA's Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) was used to construct a digital elevation model (DEM) for the study region. The preliminary risk assessment was applied to a pilot study area, the La Mosca River basin. Precipitation data from the National Aeronautics and Space Administration (NASA) Tropical Rainfall Measuring Mission (TRMM)'s near-real-time rainfall products as well as precipitation data from the Instituto de Hidrologia, Meteorologia y Estudios Ambientales (the Institute of Hydrology, Meteorology and Environmental Studies, IDEAM) and stations in the La Mosca River Basin were used to create rainfall distribution maps for the region. Using the precipitation data and the ASTER DEM, the web application, Mi Pronóstico, run by IDEAM, was updated to include an interactive map which currently allows users to search for a location and view the vulnerability and current weather and flooding conditions. The geospatial information was linked to an early warning system in Mi Pronóstico that can alert the public of flood warnings and identify locations of nearby shelters.

  19. A long-term, continuous simulation approach for large-scale flood risk assessments

    Science.gov (United States)

    Falter, Daniela; Schröter, Kai; Viet Dung, Nguyen; Vorogushyn, Sergiy; Hundecha, Yeshewatesfa; Kreibich, Heidi; Apel, Heiko; Merz, Bruno

    2014-05-01

    The Regional Flood Model (RFM) is a process based model cascade developed for flood risk assessments of large-scale basins. RFM consists of four model parts: the rainfall-runoff model SWIM, a 1D channel routing model, a 2D hinterland inundation model and the flood loss estimation model for residential buildings FLEMOps+r. The model cascade was recently undertaken a proof-of-concept study at the Elbe catchment (Germany) to demonstrate that flood risk assessments, based on a continuous simulation approach, including rainfall-runoff, hydrodynamic and damage estimation models, are feasible for large catchments. The results of this study indicated that uncertainties are significant, especially for hydrodynamic simulations. This was basically a consequence of low data quality and disregarding dike breaches. Therefore, RFM was applied with a refined hydraulic model setup for the Elbe tributary Mulde. The study area Mulde catchment comprises about 6,000 km2 and 380 river-km. The inclusion of more reliable information on overbank cross-sections and dikes considerably improved the results. For the application of RFM for flood risk assessments, long-term climate input data is needed to drive the model chain. This model input was provided by a multi-site, multi-variate weather generator that produces sets of synthetic meteorological data reproducing the current climate statistics. The data set comprises 100 realizations of 100 years of meteorological data. With the proposed continuous simulation approach of RFM, we simulated a virtual period of 10,000 years covering the entire flood risk chain including hydrological, 1D/2D hydrodynamic and flood damage estimation models. This provided a record of around 2.000 inundation events affecting the study area with spatially detailed information on inundation depths and damage to residential buildings on a resolution of 100 m. This serves as basis for a spatially consistent, flood risk assessment for the Mulde catchment presented in

  20. 44 CFR 65.11 - Evaluation of sand dunes in mapping coastal flood hazard areas.

    Science.gov (United States)

    2010-10-01

    ... mapping coastal flood hazard areas. 65.11 Section 65.11 Emergency Management and Assistance FEDERAL... Insurance Program IDENTIFICATION AND MAPPING OF SPECIAL HAZARD AREAS § 65.11 Evaluation of sand dunes in mapping coastal flood hazard areas. (a) General conditions. For purposes of the NFIP, FEMA will consider...

  1. Flood hazard assessment using 1D and 2D approaches

    Science.gov (United States)

    Petaccia, Gabriella; Costabile, Pierfranco; Macchione, Francesco; Natale, Luigi

    2013-04-01

    The EU flood risk Directive (Directive 2007/60/EC) prescribes risk assessment and mapping to develop flood risk management plans. Flood hazard mapping may be carried out with mathematical models able to determine flood-prone areas once realistic conditions (in terms of discharge or water levels) are imposed at the boundaries of the case study. The deterministic models are mainly based on shallow water equations expressed in their 1D or 2D formulation. The 1D approach is widely used, especially in technical studies, due to its relative simplicity, its computational efficiency and also because it requires topographical data not as expensive as the ones needed by 2D models. Even if in a great number of practical situations, such as modeling in-channel flows and not too wide floodplains, the 1D approach may provide results close to the prediction of a more sophisticated 2D model, it must be pointed out that the correct use of a 1D model in practical situations is more complex than it may seem. The main issues to be correctly modeled in a 1D approach are the definition of hydraulic structures such as bridges and buildings interacting with the flow and the treatment of the tributaries. Clearly all these aspects have to be taken into account also in the 2D modeling, but with fewer difficulties. The purpose of this paper is to show how the above cited issues can be described using a 1D or 2D unsteady flow modeling. In particular the Authors will show the devices that have to be implemented in 1D modeling to get reliable predictions of water levels and discharges comparable to the ones obtained using a 2D model. Attention will be focused on an actual river (Crati river) located in the South of Italy. This case study is quite complicated since it deals with the simulation of channeled flows, overbank flows, interactions with buildings, bridges and tributaries. Accurate techniques, intentionally developed by the Authors to take into account all these peculiarities in 1D and 2

  2. Analysis of economic vulnerability to flash floods in urban areas of Castilla y León (Spain)

    Science.gov (United States)

    Aroca-Jimenez, Estefanía; Bodoque, Jose Maria; García, Juan Antonio; Diez-Herrero, Andres

    2017-04-01

    The growth of exposed population to floods, the expansion in allocation of economical activities to flood-prone areas and the rise of extraordinary event frequency over the last few decades, have resulted in an increase of flash flood-related casualties and economic losses. The increase in these losses at an even higher rate than the increase of magnitude and frequency of extreme events, underline that the vulnerability of societies exposed is a key aspect to be considered. Vulnerability is defined as the conditions determined by physical, social, economic and environmental factors or processes which increase the susceptibility of a community to the impact of hazards such as floods, being flash floods one of the natural hazards with the greatest capacity to generate risk. In recent years, numerous papers have deal with the assessment of the social dimension of vulnerability. However, economic factors are often a neglected aspect in traditional risk assessments which mainly focus on structural measures and flood damage models. In this context, the aim of this research is to identify those economic characteristics which render people vulnerable to flash flood hazard, and consider whether these characteristics are identifiable as local patterns at regional level. The result of this task is an Economic Vulnerability Index (EVI) based on susceptibility profiles of the population per township. These profiles are obtained by Hierarchical Segmentation and Latent Class Cluster Analysis of economic information provided by different public institutional databases. The methodology proposed here is implemented in the region of Castilla y León (94,230 km2), placed in Central-Northern Spain. Townships included in this study meet two requirements: i) urban areas are potentially affected by flash floods (i.e. villages are crossed by rivers or streams with a longitudinal slope higher than 0.01 m m-1); ii) urban areas are affected by an area with low or exceptional probability of

  3. A Flood Risk Assessment of Quang Nam, Vietnam Using Spatial Multicriteria Decision Analysis

    Directory of Open Access Journals (Sweden)

    Chinh Luu

    2018-04-01

    Full Text Available Vietnam is highly vulnerable to flood and storm impacts. Holistic flood risk assessment maps that adequately consider flood risk factors of hazard, exposure, and vulnerability are not available. These are vital for flood risk preparedness and disaster mitigation measures at the local scale. Unfortunately, there is a lack of knowledge about spatial multicriteria decision analysis and flood risk analysis more broadly in Vietnam. In response to this need, we identify and quantify flood risk components in Quang Nam province through spatial multicriteria decision analysis. The study presents a new approach to local flood risk assessment mapping, which combines historical flood marks with exposure and vulnerability data. The flood risk map output could assist and empower decision-makers in undertaking flood risk management activities in the province. Our study demonstrates a methodology to build flood risk assessment maps using flood mark, exposure and vulnerability data, which could be applied in other provinces in Vietnam.

  4. Economic Risk Evaluation in Urban Flooding and Instability-Prone Areas: The Case Study of San Giovanni Rotondo (Southern Italy

    Directory of Open Access Journals (Sweden)

    Roberta Pellicani

    2018-03-01

    Full Text Available Estimating economic losses caused on buildings and other civil engineering works due to flooding events is often a difficult task. The accuracy of the estimate is affected by the availability of detailed data regarding the return period of the flooding event, vulnerability of exposed assets, and type of economy run in the affected area. This paper aims to provide a quantitative methodology for the assessment of economic losses associated with flood scenarios. The proposed methodology was performed for an urban area in Southern Italy prone to hydrogeological instabilities. At first, the main physical characteristics of the area such as rainfall, land use, permeability, roughness, and slopes of the area under investigation were estimated in order to obtain input for flooding simulations. Afterwards, the analysis focused on the spatial variability incidence of the rainfall parameters in flood events. The hydraulic modeling provided different flood hazard scenarios. The risk curve obtained by plotting economic consequences vs. the return period for each hazard scenario can be a useful tool for local authorities to identify adequate risk mitigation measures and therefore prioritize the economic resources necessary for the implementation of such mitigation measures.

  5. Effective delineation of urban flooded areas based on aerial ortho-photo imagery

    Science.gov (United States)

    Zhang, Ying; Guindon, Bert; Raymond, Don; Hong, Gang

    2016-10-01

    The combination of rapid global urban growth and climate change has resulted in increased occurrence of major urban flood events across the globe. The distribution of flooded area is one of the key information layers for applications of emergency planning and response management. While SAR systems and technologies have been widely used for flood area delineation, radar images suffer from range ambiguities arising from corner reflection effects and shadowing in dense urban settings. A new mapping framework is proposed for the extraction and quantification of flood extent based on aerial optical multi-spectral imagery and ancillary data. This involves first mapping of flood areas directly visible to the sensor. Subsequently, the complete area of submergence is estimated from this initial mapping and inference techniques based on baseline data such as land cover and GIS information such as available digital elevation models. The methodology has been tested and proven effective using aerial photography for the case of the 2013 flood in Calgary, Canada.

  6. LiDAR and IFSAR-Based Flood Inundation Model Estimates for Flood-Prone Areas of Afghanistan

    Science.gov (United States)

    Johnson, W. C.; Goldade, M. M.; Kastens, J.; Dobbs, K. E.; Macpherson, G. L.

    2014-12-01

    Extreme flood events are not unusual in semi-arid to hyper-arid regions of the world, and Afghanistan is no exception. Recent flashfloods and flashflood-induced landslides took nearly 100 lives and destroyed or damaged nearly 2000 homes in 12 villages within Guzargah-e-Nur district of Baghlan province in northeastern Afghanistan. With available satellite imagery, flood-water inundation estimation can be accomplished remotely, thereby providing a means to reduce the impact of such flood events by improving shared situational awareness during major flood events. Satellite orbital considerations, weather, cost, data licensing restrictions, and other issues can often complicate the acquisition of appropriately timed imagery. Given the need for tools to supplement imagery where not available, complement imagery when it is available, and bridge the gap between imagery based flood mapping and traditional hydrodynamic modeling approaches, we have developed a topographic floodplain model (FLDPLN), which has been used to identify and map river valley floodplains with elevation data ranging from 90-m SRTM to 1-m LiDAR. Floodplain "depth to flood" (DTF) databases generated by FLDPLN are completely seamless and modular. FLDPLN has been applied in Afghanistan to flood-prone areas along the northern and southern flanks of the Hindu Kush mountain range to generate a continuum of 1-m increment flood-event models up to 10 m in depth. Elevation data used in this application of FLDPLN included high-resolution, drone-acquired LiDAR (~1 m) and IFSAR (5 m; INTERMAP). Validation of the model has been accomplished using the best available satellite-derived flood inundation maps, such as those issued by Unitar's Operational Satellite Applications Programme (UNOSAT). Results provide a quantitative approach to evaluating the potential risk to urban/village infrastructure as well as to irrigation systems, agricultural fields and archaeological sites.

  7. Risk assessment of flood disaster and forewarning model at different spatial-temporal scales

    Science.gov (United States)

    Zhao, Jun; Jin, Juliang; Xu, Jinchao; Guo, Qizhong; Hang, Qingfeng; Chen, Yaqian

    2018-05-01

    Aiming at reducing losses from flood disaster, risk assessment of flood disaster and forewarning model is studied. The model is built upon risk indices in flood disaster system, proceeding from the whole structure and its parts at different spatial-temporal scales. In this study, on the one hand, it mainly establishes the long-term forewarning model for the surface area with three levels of prediction, evaluation, and forewarning. The method of structure-adaptive back-propagation neural network on peak identification is used to simulate indices in prediction sub-model. Set pair analysis is employed to calculate the connection degrees of a single index, comprehensive index, and systematic risk through the multivariate connection number, and the comprehensive assessment is made by assessment matrixes in evaluation sub-model. The comparison judging method is adopted to divide warning degree of flood disaster on risk assessment comprehensive index with forewarning standards in forewarning sub-model and then the long-term local conditions for proposing planning schemes. On the other hand, it mainly sets up the real-time forewarning model for the spot, which introduces the real-time correction technique of Kalman filter based on hydrological model with forewarning index, and then the real-time local conditions for presenting an emergency plan. This study takes Tunxi area, Huangshan City of China, as an example. After risk assessment and forewarning model establishment and application for flood disaster at different spatial-temporal scales between the actual and simulated data from 1989 to 2008, forewarning results show that the development trend for flood disaster risk remains a decline on the whole from 2009 to 2013, despite the rise in 2011. At the macroscopic level, project and non-project measures are advanced, while at the microcosmic level, the time, place, and method are listed. It suggests that the proposed model is feasible with theory and application, thus

  8. Flood risk assessment in France: comparison of extreme flood estimation methods (EXTRAFLO project, Task 7)

    Science.gov (United States)

    Garavaglia, F.; Paquet, E.; Lang, M.; Renard, B.; Arnaud, P.; Aubert, Y.; Carre, J.

    2013-12-01

    In flood risk assessment the methods can be divided in two families: deterministic methods and probabilistic methods. In the French hydrologic community the probabilistic methods are historically preferred to the deterministic ones. Presently a French research project named EXTRAFLO (RiskNat Program of the French National Research Agency, https://extraflo.cemagref.fr) deals with the design values for extreme rainfall and floods. The object of this project is to carry out a comparison of the main methods used in France for estimating extreme values of rainfall and floods, to obtain a better grasp of their respective fields of application. In this framework we present the results of Task 7 of EXTRAFLO project. Focusing on French watersheds, we compare the main extreme flood estimation methods used in French background: (i) standard flood frequency analysis (Gumbel and GEV distribution), (ii) regional flood frequency analysis (regional Gumbel and GEV distribution), (iii) local and regional flood frequency analysis improved by historical information (Naulet et al., 2005), (iv) simplify probabilistic method based on rainfall information (i.e. Gradex method (CFGB, 1994), Agregee method (Margoum, 1992) and Speed method (Cayla, 1995)), (v) flood frequency analysis by continuous simulation approach and based on rainfall information (i.e. Schadex method (Paquet et al., 2013, Garavaglia et al., 2010), Shyreg method (Lavabre et al., 2003)) and (vi) multifractal approach. The main result of this comparative study is that probabilistic methods based on additional information (i.e. regional, historical and rainfall information) provide better estimations than the standard flood frequency analysis. Another interesting result is that, the differences between the various extreme flood quantile estimations of compared methods increase with return period, staying relatively moderate up to 100-years return levels. Results and discussions are here illustrated throughout with the example

  9. An Assessment of the Effectiveness of Tree-Based Models for Multi-Variate Flood Damage Assessment in Australia

    Directory of Open Access Journals (Sweden)

    Roozbeh Hasanzadeh Nafari

    2016-07-01

    Full Text Available Flood is a frequent natural hazard that has significant financial consequences for Australia. In Australia, physical losses caused by floods are commonly estimated by stage-damage functions. These methods usually consider only the depth of the water and the type of buildings at risk. However, flood damage is a complicated process, and it is dependent on a variety of factors which are rarely taken into account. This study explores the interaction, importance, and influence of water depth, flow velocity, water contamination, precautionary measures, emergency measures, flood experience, floor area, building value, building quality, and socioeconomic status. The study uses tree-based models (regression trees and bagging decision trees and a dataset collected from 2012 to 2013 flood events in Queensland, which includes information on structural damages, impact parameters, and resistance variables. The tree-based approaches show water depth, floor area, precautionary measures, building value, and building quality to be important damage-influencing parameters. Furthermore, the performance of the tree-based models is validated and contrasted with the outcomes of a multi-parameter loss function (FLFArs from Australia. The tree-based models are shown to be more accurate than the stage-damage function. Consequently, considering more parameters and taking advantage of tree-based models is recommended. The outcome is important for improving established Australian flood loss models and assisting decision-makers and insurance companies dealing with flood risk assessment.

  10. Integrating human behaviour dynamics into flood disaster risk assessment

    Science.gov (United States)

    Aerts, J. C. J. H.; Botzen, W. J.; Clarke, K. C.; Cutter, S. L.; Hall, J. W.; Merz, B.; Michel-Kerjan, E.; Mysiak, J.; Surminski, S.; Kunreuther, H.

    2018-03-01

    The behaviour of individuals, businesses, and government entities before, during, and immediately after a disaster can dramatically affect the impact and recovery time. However, existing risk-assessment methods rarely include this critical factor. In this Perspective, we show why this is a concern, and demonstrate that although initial efforts have inevitably represented human behaviour in limited terms, innovations in flood-risk assessment that integrate societal behaviour and behavioural adaptation dynamics into such quantifications may lead to more accurate characterization of risks and improved assessment of the effectiveness of risk-management strategies and investments. Such multidisciplinary approaches can inform flood-risk management policy development.

  11. Construction of an integrated social vulnerability index in urban areas prone to flash flooding

    Science.gov (United States)

    Aroca-Jimenez, Estefania; Bodoque, Jose Maria; Garcia, Juan Antonio; Diez-Herrero, Andres

    2017-09-01

    Among the natural hazards, flash flooding is the leading cause of weather-related deaths. Flood risk management (FRM) in this context requires a comprehensive assessment of the social risk component. In this regard, integrated social vulnerability (ISV) can incorporate spatial distribution and contribution and the combined effect of exposure, sensitivity and resilience to total vulnerability, although these components are often disregarded. ISV is defined by the demographic and socio-economic characteristics that condition a population's capacity to cope with, resist and recover from risk and can be expressed as the integrated social vulnerability index (ISVI). This study describes a methodological approach towards constructing the ISVI in urban areas prone to flash flooding in Castilla y León (Castile and León, northern central Spain, 94 223 km2, 2 478 376 inhabitants). A hierarchical segmentation analysis (HSA) was performed prior to the principal components analysis (PCA), which helped to overcome the sample size limitation inherent in PCA. ISVI was obtained from weighting vulnerability factors based on the tolerance statistic. In addition, latent class cluster analysis (LCCA) was carried out to identify spatial patterns of vulnerability within the study area. Our results show that the ISVI has high spatial variability. Moreover, the source of vulnerability in each urban area cluster can be identified from LCCA. These findings make it possible to design tailor-made strategies for FRM, thereby increasing the efficiency of plans and policies and helping to reduce the cost of mitigation measures.

  12. A web GIS based integrated flood assessment modeling tool for coastal urban watersheds

    Science.gov (United States)

    Kulkarni, A. T.; Mohanty, J.; Eldho, T. I.; Rao, E. P.; Mohan, B. K.

    2014-03-01

    Urban flooding has become an increasingly important issue in many parts of the world. In this study, an integrated flood assessment model (IFAM) is presented for the coastal urban flood simulation. A web based GIS framework has been adopted to organize the spatial datasets for the study area considered and to run the model within this framework. The integrated flood model consists of a mass balance based 1-D overland flow model, 1-D finite element based channel flow model based on diffusion wave approximation and a quasi 2-D raster flood inundation model based on the continuity equation. The model code is written in MATLAB and the application is integrated within a web GIS server product viz: Web Gram Server™ (WGS), developed at IIT Bombay, using Java, JSP and JQuery technologies. Its user interface is developed using open layers and the attribute data are stored in MySQL open source DBMS. The model is integrated within WGS and is called via Java script. The application has been demonstrated for two coastal urban watersheds of Navi Mumbai, India. Simulated flood extents for extreme rainfall event of 26 July, 2005 in the two urban watersheds of Navi Mumbai city are presented and discussed. The study demonstrates the effectiveness of the flood simulation tool in a web GIS environment to facilitate data access and visualization of GIS datasets and simulation results.

  13. Assessment of the effectiveness of flood adaptation strategies for HCMC

    Science.gov (United States)

    Lasage, R.; Veldkamp, T. I. E.; de Moel, H.; Van, T. C.; Phi, H. L.; Vellinga, P.; Aerts, J. C. J. H.

    2014-06-01

    Coastal cities are vulnerable to flooding, and flood risk to coastal cities will increase due to sea-level rise. Moreover, Asian cities in particular are subject to considerable population growth and associated urban developments, increasing this risk even more. Empirical data on vulnerability and the cost and benefits of flood risk reduction measures are therefore paramount for sustainable development of these cities. This paper presents an approach to explore the impacts of sea-level rise and socio-economic developments on flood risk for the flood-prone District 4 in Ho Chi Minh City, Vietnam, and to develop and evaluate the effects of different adaptation strategies (new levees, dry- and wet proofing of buildings and elevating roads and buildings). A flood damage model was developed to simulate current and future flood risk using the results from a household survey to establish stage-damage curves for residential buildings. The model has been used to assess the effects of several participatory developed adaptation strategies to reduce flood risk, expressed in expected annual damage (EAD). Adaptation strategies were evaluated assuming combinations of both sea-level scenarios and land-use scenarios. Together with information on costs of these strategies, we calculated the benefit-cost ratio and net present value for the adaptation strategies until 2100, taking into account depreciation rates of 2.5% and 5%. The results of this modelling study indicate that the current flood risk in District 4 is USD 0.31 million per year, increasing up to USD 0.78 million per year in 2100. The net present value and benefit-cost ratios using a discount rate of 5 % range from USD -107 to -1.5 million, and from 0.086 to 0.796 for the different strategies. Using a discount rate of 2.5% leads to an increase in both net present value and benefit-cost ratio. The adaptation strategies wet-proofing and dry-proofing generate the best results using these economic indicators. The information

  14. Identification and delineation of areas flood hazard using high accuracy of DEM data

    Science.gov (United States)

    Riadi, B.; Barus, B.; Widiatmaka; Yanuar, M. J. P.; Pramudya, B.

    2018-05-01

    Flood incidents that often occur in Karawang regency need to be mitigated. These expectations exist on technologies that can predict, anticipate and reduce disaster risks. Flood modeling techniques using Digital Elevation Model (DEM) data can be applied in mitigation activities. High accuracy DEM data used in modeling, will result in better flooding flood models. The result of high accuracy DEM data processing will yield information about surface morphology which can be used to identify indication of flood hazard area. The purpose of this study was to identify and describe flood hazard areas by identifying wetland areas using DEM data and Landsat-8 images. TerraSAR-X high-resolution data is used to detect wetlands from landscapes, while land cover is identified by Landsat image data. The Topography Wetness Index (TWI) method is used to detect and identify wetland areas with basic DEM data, while for land cover analysis using Tasseled Cap Transformation (TCT) method. The result of TWI modeling yields information about potential land of flood. Overlay TWI map with land cover map that produces information that in Karawang regency the most vulnerable areas occur flooding in rice fields. The spatial accuracy of the flood hazard area in this study was 87%.

  15. USGS environmental characterization of flood sediments left in the New Orleans area after Hurricanes Katrina and Rita, 2005--Progress Report

    Science.gov (United States)

    Plumlee, Geoffrey S.; Meeker, Gregory P.; Lovelace, John K.; Rosenbauer, Robert J.; Lamothe, Paul J.; Furlong, Edward T.; Demas, Charles R.

    2006-01-01

    Introduction: The flooding in the greater New Orleans area that resulted from Hurricanes Katrina and Rita in September, 2005, left behind accumulations of sediments up to many centimeters thick on streets, lawns, parking lots, and other flat surfaces. These flood sediment deposits have been the focus of extensive study by the US Environmental Protection Agency (EPA) and Louisiana Department of Environmental Quality (LDEQ) due to concerns that the sediments may contain elevated levels of heavy metals, organic contaminants, and microbes. The U.S. Geological Survey (USGS) is characterizing a limited number of flood sediment samples that were collected on September 15-16 and October 6-7, 2005, from the greater New Orleans area by personnel from the USGS Louisiana Water Science Center in Baton Rouge. Small samples (< 3 pints each) of wet to dry flood sediment were collected from 11 localities around downtown New Orleans on September 15, 2005, and two large samples (40 pints each) of wet flood sediment were collected from the Chalmette area on September 16. Twelve additional samples (8-10 pints each) were collected from New Orleans, Slidell, Rigolets, and Violet on October 6 and 7. The USGS characterization studies of these flood sediments are designed to produce data and interpretations regarding how the sediments and any contained contaminants may respond to environmental processes. This information will be of use to cleanup managers and DoI/USGS scientists assessing environmental impacts of the hurricanes and subsequent cleanup activities.

  16. 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.

  17. ICUD-0147 Extreme event statistics of urban pluvial floods – Return period assessment and rainfall variability impacts

    DEFF Research Database (Denmark)

    Tuyls, Damian Murla; Nielsen, Rasmus; Thorndahl, Søren Liedtke

    2017-01-01

    A return period assessment of urban flood has been performed and its adhered impact of rainfall variability studied over a urban drainage catchment area in Aalborg, Denmark. Recorded rainfall from 7 rain gauges has been used, located in a range of 7.5Km and for a period varying form 18-37 years....... Return period of rainfall and flood at catchment and local scale has been estimated, its derived ambiguities analysed and the variability of rain gauge based rainfall investigated regarding to flood estimation results. Results show a clear contrast between rainfall and flood return period estimates...

  18. Survey of Microbial Diversity in Flood Areas during Thailand 2011 Flood Crisis Using High-Throughput Tagged Amplicon Pyrosequencing.

    Science.gov (United States)

    Mhuantong, Wuttichai; Wongwilaiwalin, Sarunyou; Laothanachareon, Thanaporn; Eurwilaichitr, Lily; Tangphatsornruang, Sithichoke; Boonchayaanant, Benjaporn; Limpiyakorn, Tawan; Pattaragulwanit, Kobchai; Punmatharith, Thantip; McEvoy, John; Khan, Eakalak; Rachakornkij, Manaskorn; Champreda, Verawat

    2015-01-01

    The Thailand flood crisis in 2011 was one of the largest recorded floods in modern history, causing enormous damage to the economy and ecological habitats of the country. In this study, bacterial and fungal diversity in sediments and waters collected from ten flood areas in Bangkok and its suburbs, covering residential and agricultural areas, were analyzed using high-throughput 454 pyrosequencing of 16S rRNA gene and internal transcribed spacer sequences. Analysis of microbial community showed differences in taxa distribution in water and sediment with variations in the diversity of saprophytic microbes and sulfate/nitrate reducers among sampling locations, suggesting differences in microbial activity in the habitats. Overall, Proteobacteria represented a major bacterial group in waters, while this group co-existed with Firmicutes, Bacteroidetes, and Actinobacteria in sediments. Anaeromyxobacter, Steroidobacter, and Geobacter were the dominant bacterial genera in sediments, while Sulfuricurvum, Thiovirga, and Hydrogenophaga predominated in waters. For fungi in sediments, Ascomycota, Glomeromycota, and Basidiomycota, particularly in genera Philipsia, Rozella, and Acaulospora, were most frequently detected. Chytridiomycota and Ascomycota were the major fungal phyla, and Rhizophlyctis and Mortierella were the most frequently detected fungal genera in water. Diversity of sulfate-reducing bacteria, related to odor problems, was further investigated using analysis of the dsrB gene which indicated the presence of sulfate-reducing bacteria of families Desulfobacteraceae, Desulfobulbaceae, Syntrobacteraceae, and Desulfoarculaceae in the flood sediments. The work provides an insight into the diversity and function of microbes related to biological processes in flood areas.

  19. Effects of flood on farmers in peri-urban area of Ibadan, Oyo state ...

    African Journals Online (AJOL)

    One of the commonest environmental hazards threatening food security now in Nigeria is flood. The study therefore investigated the effects of flood on farmers in peri – urban areas of Ibadan. Using a snow ball research method, 60 farmers were selected from the six local governments in the peri – urban areas of Ibadan and ...

  20. Blending satellite data and RADAR tool for rapid flood damage assessment in Agriculture: A case study in Sri Lanka

    Science.gov (United States)

    Amarnath, Giriraj; Inada, Yoshiaki; Inoue, Ryosuke; Alahacoon, Niranga; Smakhtin, Vladimir

    2014-05-01

    During the catastrophic flooding it is critically important to estimate losses as it is essential for facilitating good decision making at the district, province and national levels of government and to appraise aid agencies for necessary assistance. Flood loss estimates can also be used to evaluate the cost effectiveness of alternative approaches to strengthening flood control measures. In the case of Sri Lanka there were limited knowledge and application system exist for carrying out rapid damage assessment for Agriculture in Sri Lanka. FAO has developed the tool "Rapid Agricultural Disaster Assessment Routine" (RADAR) based on theoretical approach that uses simple tools for assessing the impact on agriculture of a disastrous event. There are two knowledge bases that contain information needed for calculation of the value loss or damage. The procedure of rapid impact assessment implies the use of knowledge-bases, database and GIS. In this study, the user friendly application of RADAR system has been developed. Three components were considered including agriculture, livestock and farmers asset to estimate the losses. The application will allow estimating flood damage at various scales and this being tested at district level and specific example for the 2011 floods in Sri Lanka. In order to understand flood inundation cycle, time-series optical MODIS satellite data (2000-2011) and microwave ALOS PALSAR (2006-2011) were used to derive annual flood extent, flood duration and recurrent areas to identify flood risk and impact of seasonal flooding on agriculture. This study demonstrates how RADAR & satellite-based flood products can be effectively used for rapid damage assessment and managing the floods.

  1. Geomorphic Assessment of Floods within the Urban Environment of ...

    African Journals Online (AJOL)

    This study examined urban geomorphic conditions that lead to flooding in urban areas of ... the elimination of vegetation cover as well as deficient drainage networks ... Department of Geography & Resource Development, University of Ghana, Legon, .... A number of case studies from different parts of the world dealing.

  2. Forecasting flood-prone areas using Shannon's entropy model

    Indian Academy of Sciences (India)

    2Department of Water Engineering, Faculty of Agriculture, Lorestan University, ... decision tree methods for determining flood sus- .... a system to prevent disorder, instability, distur- ..... using support vector machine and GIS at the Golestan.

  3. Flood-risk mapping: contributions towards an enhanced assessment of extreme events and associated risks

    Directory of Open Access Journals (Sweden)

    B. Büchele

    2006-01-01

    Full Text Available Currently, a shift from classical flood protection as engineering task towards integrated flood risk management concepts can be observed. In this context, a more consequent consideration of extreme events which exceed the design event of flood protection structures and failure scenarios such as dike breaches have to be investigated. Therefore, this study aims to enhance existing methods for hazard and risk assessment for extreme events and is divided into three parts. In the first part, a regionalization approach for flood peak discharges was further developed and substantiated, especially regarding recurrence intervals of 200 to 10 000 years and a large number of small ungauged catchments. Model comparisons show that more confidence in such flood estimates for ungauged areas and very long recurrence intervals may be given as implied by statistical analysis alone. The hydraulic simulation in the second part is oriented towards hazard mapping and risk analyses covering the whole spectrum of relevant flood events. As the hydrodynamic simulation is directly coupled with a GIS, the results can be easily processed as local inundation depths for spatial risk analyses. For this, a new GIS-based software tool was developed, being presented in the third part, which enables estimations of the direct flood damage to single buildings or areas based on different established stage-damage functions. Furthermore, a new multifactorial approach for damage estimation is presented, aiming at the improvement of damage estimation on local scale by considering factors like building quality, contamination and precautionary measures. The methods and results from this study form the base for comprehensive risk analyses and flood management strategies.

  4. High-resolution flood modeling of urban areas using MSN_Flood

    Directory of Open Access Journals (Sweden)

    Michael Hartnett

    2017-07-01

    Full Text Available Although existing hydraulic models have been used to simulate and predict urban flooding, most of these models are inadequate due to the high spatial resolution required to simulate flows in urban floodplains. Nesting high-resolution subdomains within coarser-resolution models is an efficient solution for enabling simultaneous calculation of flooding due to tides, surges, and high river flows. MSN_Flood has been developed to incorporate moving boundaries around nested domains, permitting alternate flooding and drying along the boundary and in the interior of the domain. Ghost cells adjacent to open boundary cells convert open boundaries, in effect, into internal boundaries. The moving boundary may be multi-segmented and non-continuous, with recirculating flow across the boundary. When combined with a bespoke adaptive interpolation scheme, this approach facilitates a dynamic internal boundary. Based on an alternating-direction semi-implicit finite difference scheme, MSN_Flood was used to hindcast a major flood event in Cork City resulting from the combined pressures of fluvial, tidal, and storm surge processes. The results show that the model is computationally efficient, as the 2-m high-resolution nest is used only in the urban flooded region. Elsewhere, lower-resolution nests are used. The results also show that the model is highly accurate when compared with measured data. The model is capable of incorporating nested sub-domains when the nested boundary is multi-segmented and highly complex with lateral gradients of elevation and velocities. This is a major benefit when modelling urban floodplains at very high resolution.

  5. Analysis of flood vulnerability in urban area; a case study in deli watershed

    Science.gov (United States)

    Indrawan, I.; Siregar, R. I.

    2018-03-01

    Based on the National Disaster Management Agency of Indonesia, the distribution of disasters and victims died until the year 2016 is the largest flood disaster. Deli River is a river that has the greatest flood potential through Medan City. In Deli Watershed, flow discharge affected by the discharge from its tributaries, the high rainfall intensity and human activity. We should anticipate reducing and preventing the occurrence of losses due to flood damage. One of the ways to anticipate flood disaster is to predict which part of urban area is would flood. The objective of this study is to analyze the flood inundation areas due to overflow of Deli River through Medan city. Two-dimensional modeling by HEC-RAS 5.0.3 is a widely used hydraulic software tool developed by the U.S Army Corps of Engineers, which combined with the HEC-HMS for hydrological modeling. The result shows flood vulnerability in Medan by a map to present the spot that vulnerable about flood. The flooded area due to the overflowing of Deli River consists of seven sub districts, namely Medan Johor, Medan Selayang, Medan Kota, Medan Petisah, Medan Maimun, Medan Perjuangan and Medan Barat.

  6. Assessment of channel changes, model of historical floods, and effects of backwater on flood stage, and flood mitigation alternatives for the Wichita River at Wichita Falls, Texas

    Science.gov (United States)

    Winters, Karl E.; Baldys, Stanley

    2011-01-01

    In cooperation with the City of Wichita Falls, the U.S. Geological Survey assessed channel changes on the Wichita River at Wichita Falls, Texas, and modeled historical floods to investigate possible causes and potential mitigation alternatives to higher flood stages in recent (2007 and 2008) floods. Extreme flooding occurred on the Wichita River on June 30, 2007, inundating 167 homes in Wichita Falls. Although a record flood stage was reached in June 2007, the peak discharge was much less than some historical floods at Wichita Falls. Streamflow and stage data from two gages on the Wichita River and one on Holliday Creek were used to assess the interaction of the two streams. Changes in the Wichita River channel were evaluated using historical aerial and ground photography, comparison of recent and historical cross sections, and comparison of channel roughness coefficients with those from earlier studies. The floods of 2007 and 2008 were modeled using a one-dimensional step-backwater model. Calibrated channel roughness was larger for the 2007 flood compared to the 2008 flood, and the 2007 flood peaked about 4 feet higher than the 2008 flood. Calibration of the 1941 flood yielded a channel roughness coefficient (Manning's n) of 0.030, which represents a fairly clean natural channel. The step-backwater model was also used to evaluate the following potential mitigation alternatives: (1) increasing the capacity of the bypass channel near River Road in Wichita Falls, Texas; (2) removal of obstructions near the Scott Avenue and Martin Luther King Junior Boulevard bridges in Wichita Falls, Texas; (3) widening of aggraded channel banks in the reach between Martin Luther King Junior Boulevard and River Road; and (4) reducing channel bank and overbank roughness. Reductions in water-surface elevations ranged from 0.1 foot to as much as 3.0 feet for the different mitigation alternatives. The effects of implementing a combination of different flood-mitigation alternatives were

  7. Maximum flood hazard assessment for OPG's deep geologic repository for low and intermediate level waste

    International Nuclear Information System (INIS)

    Nimmrichter, P.; McClintock, J.; Peng, J.; Leung, H.

    2011-01-01

    Ontario Power Generation (OPG) has entered a process to seek Environmental Assessment and licensing approvals to construct a Deep Geologic Repository (DGR) for Low and Intermediate Level Radioactive Waste (L&ILW) near the existing Western Waste Management Facility (WWMF) at the Bruce nuclear site in the Municipality of Kincardine, Ontario. In support of the design of the proposed DGR project, maximum flood stages were estimated for potential flood hazard risks associated with coastal, riverine and direct precipitation flooding. The estimation of lake/coastal flooding for the Bruce nuclear site considered potential extreme water levels in Lake Huron, storm surge and seiche, wind waves, and tsunamis. The riverine flood hazard assessment considered the Probable Maximum Flood (PMF) within the local watersheds, and within local drainage areas that will be directly impacted by the site development. A series of hydraulic models were developed, based on DGR project site grading and ditching, to assess the impact of a Probable Maximum Precipitation (PMP) occurring directly at the DGR site. Overall, this flood assessment concluded there is no potential for lake or riverine based flooding and the DGR area is not affected by tsunamis. However, it was also concluded from the results of this analysis that the PMF in proximity to the critical DGR operational areas and infrastructure would be higher than the proposed elevation of the entrance to the underground works. This paper provides an overview of the assessment of potential flood hazard risks associated with coastal, riverine and direct precipitation flooding that was completed for the DGR development. (author)

  8. Assessment of the Influence of the Hydrological Regime of the Volga River on the Dynamics of Flooding on Sarpinsky Island

    Directory of Open Access Journals (Sweden)

    A.S. Rulev

    2017-03-01

    Full Text Available The seasonal dynamics of flooding on Sarpinsky Island, which is included in the city of Volgograd, following the damming by the Volga HPP has been considered. The following research problems have been set: firstly, to establish seasonal patterns of flooding in the island territory; secondly, to find out if there is a flooding threat to social infrastructure facilities. The flooded area of the island has been assessed by Landsat multispectral images with a spatial resolution of 30 m. Only images with the survey date corresponding to the peak of high waters (with the difference of not more than 7–10 days have been analyzed. The flooding areas of the island have been calculated for the date when flooding peaked (April–May during the period from 1985 to 2016. The phases of spring flooding determined by the island landscape and the water discharge from the Volga HPP have been revealed. The curve of the area of flooding reaches maximum values after the water discharge is up to 11–12 km3, which depends on the initial filling of floodplain reservoirs (landscape depressions in depth without any increase in the area of flooding. The average shift between the peaks of water discharge and the area of flooding is 10–15 days and reflects gradual filling of floodplain reservoirs on Sarpinsky Island after the beginning of water discharge from the Volga HPP. It has been found that there is no threat to infrastructure facilities on Sarpinsky Island under the current volumes of water discharge during the flooding period. The obtained results are important for urban planning on the island, as well as for management of the regimes of water passage through the dam of the Volga HPP.

  9. A comparative assessment of decision trees algorithms for flash flood susceptibility modeling at Haraz watershed, northern Iran.

    Science.gov (United States)

    Khosravi, Khabat; Pham, Binh Thai; Chapi, Kamran; Shirzadi, Ataollah; Shahabi, Himan; Revhaug, Inge; Prakash, Indra; Tien Bui, Dieu

    2018-06-15

    Floods are one of the most damaging natural hazards causing huge loss of property, infrastructure and lives. Prediction of occurrence of flash flood locations is very difficult due to sudden change in climatic condition and manmade factors. However, prior identification of flood susceptible areas can be done with the help of machine learning techniques for proper timely management of flood hazards. In this study, we tested four decision trees based machine learning models namely Logistic Model Trees (LMT), Reduced Error Pruning Trees (REPT), Naïve Bayes Trees (NBT), and Alternating Decision Trees (ADT) for flash flood susceptibility mapping at the Haraz Watershed in the northern part of Iran. For this, a spatial database was constructed with 201 present and past flood locations and eleven flood-influencing factors namely ground slope, altitude, curvature, Stream Power Index (SPI), Topographic Wetness Index (TWI), land use, rainfall, river density, distance from river, lithology, and Normalized Difference Vegetation Index (NDVI). Statistical evaluation measures, the Receiver Operating Characteristic (ROC) curve, and Freidman and Wilcoxon signed-rank tests were used to validate and compare the prediction capability of the models. Results show that the ADT model has the highest prediction capability for flash flood susceptibility assessment, followed by the NBT, the LMT, and the REPT, respectively. These techniques have proven successful in quickly determining flood susceptible areas. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Assessing the Effects of Periodic Flooding on the Population Structure and Recruitment Rates of Riparian Tree Forests

    Directory of Open Access Journals (Sweden)

    Jean-Sébastien Berthelot

    2014-08-01

    Full Text Available Riparian forest stands are subjected to a variety of hydrological stresses as a result of annual fluctuations in water levels during the growing season. Spring floods create additional water-related stress as a result of a major inflow of water that floods riverside land. This exploratory study assesses the impacts of successive floods on tree dynamics and regeneration in an active sedimentation area, while determining the age of the stands using the recruitment rates, tree structure and tree rings based on dendrochronological analysis. Environmental data were also recorded for each vegetation quadrat. In total, 2633 tree stems were tallied throughout the quadrats (200 m2, and tree specimens were analyzed based on the various flood zones. A total of 720 specimens were counted (100 m2 strip to measure natural regeneration. Higher recruitment rates are noted for the no-flood zones and lower rates in active floodplains. During the period of the establishment of tree species, the survival rates are comparable between the flood zones and the no-flood zones. Tree diameter distribution reveals a strong predominance of young trees in flooded areas. Different factors appear to come into play in the dynamics of riparian forest stands, including the disruptions associated with successive flooding.

  11. Dynamic model of forest area on flood zone of Padang City, West Sumatra Province-Indonesia

    Science.gov (United States)

    Dewata, Indang; Iswandi, U.

    2018-05-01

    The flood disaster has caused many harm to human life, and the change of watershed characteristic is one of the factors causing the flood disaster. The increase of deforestation due to the increase of water causes the occurrence of flood disaster in the rainy season. The research objective was to develop a dynamic model of forest on flood hazard zone using powersim 10.1. In model development, there are three scenarios: optimistic, moderate, and pessimistic. The study shows that in Padang there are about 13 percent of high flood hazard zones. Deforestation of 4.5 percent/year is one cause that may increased the flooding intensity in Padang. There will be 14 percent of total forest area when management policy of forest absence in 2050.

  12. Urban flooding and health risk analysis by use of quantitative microbial risk assessment

    DEFF Research Database (Denmark)

    Andersen, Signe Tanja

    D thesis is to identify the limitations and possibilities for optimising microbial risk assessments of urban flooding through more evidence-based solutions, including quantitative microbial data and hydrodynamic water quality models. The focus falls especially on the problem of data needs and the causes......, but also when wading through a flooded area. The results in this thesis have brought microbial risk assessments one step closer to more uniform and repeatable risk analysis by using actual and relevant measured data and hydrodynamic water quality models to estimate the risk from flooding caused...... are expected to increase in the future. To ensure public health during extreme rainfall, solutions are needed, but limited knowledge on microbial water quality, and related health risks, makes it difficult to implement microbial risk analysis as a part of the basis for decision making. The main aim of this Ph...

  13. Flood Hazard Recurrence Frequencies for C-, F-, E-, S-, H-, Y-, and Z-Areas

    International Nuclear Information System (INIS)

    Chen, K.F.

    1999-01-01

    A method was developed to determine the probabilistic flood elevation curves for Savannah River Site facilities. This report presents the method used to determine the probabilistic flood elevation curves for C-, F-, E-, H-, S-, Y-, and Z-Areas due to runoff from the Upper Three Runs and Fourmile Branch basins

  14. Investigating flood susceptible areas in inaccessible regions using remote sensing and geographic information systems.

    Science.gov (United States)

    Lim, Joongbin; Lee, Kyoo-Seock

    2017-03-01

    Every summer, North Korea (NK) suffers from floods, resulting in decreased agricultural production and huge economic loss. Besides meteorological reasons, several factors can accelerate flood damage. Environmental studies about NK are difficult because NK is inaccessible due to the division of Korea. Remote sensing (RS) can be used to delineate flood inundated areas in inaccessible regions such as NK. The objective of this study was to investigate the spatial characteristics of flood susceptible areas (FSAs) using multi-temporal RS data and digital elevation model data. Such study will provide basic information to restore FSAs after reunification. Defining FSAs at the study site revealed that rice paddies with low elevation and low slope were the most susceptible areas to flood in NK. Numerous sediments from upper streams, especially streams through crop field areas on steeply sloped hills, might have been transported and deposited into stream channels, thus disturbing water flow. In conclusion, NK floods may have occurred not only due to meteorological factors but also due to inappropriate land use for flood management. In order to mitigate NK flood damage, reforestation is needed for terraced crop fields. In addition, drainage capacity for middle stream channel near rice paddies should be improved.

  15. Risk assessment of urban flood disaster in Jingdezhen City based on analytic hierarchy process and geographic information system

    Science.gov (United States)

    Sun, D. C.; Huang, J.; Wang, H. M.; Wang, Z. Q.; Wang, W. Q.

    2017-08-01

    The research of urban flood risk assessment and management are of great academic and practical importance, which has become a widespread concern throughout the world. It’s significant to understand the spatial-temporal distribution of the flood risk before making the risk response measures. In this study, the urban region of Jingdezhen City is selected as the study area. The assessment indicators are selected from four aspects: disaster-causing factors, disaster-pregnant environment, disaster-bearing body and the prevention and mitigation ability, by consideration of the formation process of urban flood risk. And then, a small-scale flood disaster risk assessment model is developed based on Analytic Hierarchy Process(AHP) and Geographic Information System(GIS), and the spatial-temporal distribution of flood risk in Jingdezhen City is analysed. The results show that the risk decreases gradually from the centre line of Changjiang River to the surrounding, and the areas of high flood disaster risk is decreasing from 2010 to 2013 while the risk areas are more concentred. The flood risk of the areas along the Changjiang River is the largest, followed by the low-lying areas in Changjiang District. And the risk is also large in Zhushan District where the population, the industries and commerce are concentrated. The flood risk in the western part of Changjiang District and the north-eastern part of the study area is relatively low. The results can provide scientific support for flood control construction and land development planning in Jingdezhen City.

  16. Flood occurrence mapping of the middle Mahakam lowland area using satellite radar

    Directory of Open Access Journals (Sweden)

    H. Hidayat

    2012-07-01

    Full Text Available Floodplain lakes and peatlands in the middle Mahakam lowland area are considered as ecologically important wetland in East Kalimantan, Indonesia. However, due to a lack of data, the hydrological functioning of the region is still poorly understood. Among remote sensing techniques that can increase data availability, radar is well-suitable for the identification, mapping, and measurement of tropical wetlands, for its cloud unimpeded sensing and night and day operation. Here we aim to extract flood extent and flood occurrence information from a series of radar images of the middle Mahakam lowland area. We explore the use of Phased Array L-band Synthetic Aperture Radar (PALSAR imagery for observing flood inundation dynamics by incorporating field water level measurements. Water level measurements were carried out along the river, in lakes and in peatlands, using pressure transducers. For validation of the open water flood occurrence map, bathymetry measurements were carried out in the main lakes. A series of PALSAR images covering the middle and lower Mahakam area in the years 2007 through 2010 were collected. A fully inundated region can be easily recognized on radar images from a dark signature. Open water flood occurrence was mapped using a threshold value taken from radar backscatter of the permanently inundated river and lakes areas. Radar backscatter intensity analysis of the vegetated floodplain area revealed consistently high backscatter values, indicating flood inundation under forest canopy. We used those values as the threshold for flood occurrence mapping in the vegetated area.

  17. Investigation of Flood Risk Assessment in Inaccessible Regions using Multiple Remote Sensing and Geographic Information Systems

    Science.gov (United States)

    Lim, J.; Lee, K. S.

    2017-12-01

    Flooding is extremely dangerous when a river overflows to inundate an urban area. From 1995 to 2016, North Korea (NK) experienced annual extensive damage to life and property almost each year due to a levee breach resulting from typhoons and heavy rainfall during the summer monsoon season. Recently, Hoeryeong City (2016) experienced heavy rainfall during typhoon Lionrock and the resulting flood killed and injured many people (68,900) and destroyed numerous buildings and settlements (11,600). The NK state media described it as the biggest national disaster since 1945. Thus, almost all annual repeat occurrences of floods in NK have had a serious impact, which makes it necessary to figure out the extent of floods in restoring the damaged environment. In addition, traditional hydrological model is impractical to delineate Flood Damaged Areas (FDAs) in NK due to the inaccessibility. Under such a situation, multiple optical Remote Sensing (RS) and radar RS along with a Geographic Information System (GIS)-based spatial analysis were utilized in this study (1) to develop modelling FDA delineation using multiple RS and GIS methods and (2) to conduct flood risk assessment in NK. Interpreting high-resolution web-based satellite imagery were also implemented to confirm the results of the study. From the study result, it was found that (1) on August 30th, 2016, an area of 117.2 km2 (8.6%) at Hoeryeong City was inundated. Most floods occurred in flat areas with a lower and middle stream order. (2) In the binary logistic regression model applied in this study, the distance from the nearest stream map and landform map variables are important factors to delineate FDAs because these two factors reflect heterogeneous mountainous NK topography. (3) Total annual flood risk of study area is estimated to be ₩454.13 million NKW ($504,417.24 USD, and ₩576.53 million SKW). The risk of the confluence of the Tumen River and Hoeryeong stream appears to be the highest. (4) High resolution

  18. Mapping Infected Area after a Flash-Flooding Storm Using Multi Criteria Analysis and Spectral Indices

    Science.gov (United States)

    Al-Akad, S.; Akensous, Y.; Hakdaoui, M.

    2017-11-01

    This research article is summarize the applications of remote sensing and GIS to study the urban floods risk in Al Mukalla. Satellite acquisition of a flood event on October 2015 in Al Mukalla (Yemen) by using flood risk mapping techniques illustrate the potential risk present in this city. Satellite images (The Landsat and DEM images data were atmospherically corrected, radiometric corrected, and geometric and topographic distortions rectified.) are used for flood risk mapping to afford a hazard (vulnerability) map. This map is provided by applying image-processing techniques and using geographic information system (GIS) environment also the application of NDVI, NDWI index, and a method to estimate the flood-hazard areas. Four factors were considered in order to estimate the spatial distribution of the hazardous areas: flow accumulation, slope, land use, geology and elevation. The multi-criteria analysis, allowing to deal with vulnerability to flooding, as well as mapping areas at the risk of flooding of the city Al Mukalla. The main object of this research is to provide a simple and rapid method to reduce and manage the risks caused by flood in Yemen by take as example the city of Al Mukalla.

  19. Flood Risk Assessment and Forecasting for the Ganges-Brahmaputra-Meghna River Basins

    Science.gov (United States)

    Hopson, T. M.; Priya, S.; Young, W.; Avasthi, A.; Clayton, T. D.; Brakenridge, G. R.; Birkett, C. M.; Riddle, E. E.; Broman, D.; Boehnert, J.; Sampson, K. M.; Kettner, A.; Singh, D.

    2017-12-01

    During the 2017 South Asia monsoon, torrential rains and catastrophic floods affected more than 45 million people, including 16 million children, across the Ganges-Brahmaputra-Meghna (GBM) basins. The basin is recognized as one of the world's most disaster-prone regions, with severe floods occurring almost annually causing extreme loss of life and property. In light of this vulnerability, the World Bank and collaborators have contributed toward reducing future flood impacts through recent developments to improve operational preparedness for such events, as well as efforts in more general preparedness and resilience building through planning based on detailed risk assessments. With respect to improved event-specific flood preparedness through operational warnings, we discuss a new forecasting system that provides probability-based flood forecasts developed for more than 85 GBM locations. Forecasts are available online, along with near-real-time data maps of rainfall (predicted and actual) and river levels. The new system uses multiple data sets and multiple models to enhance forecasting skill, and provides improved forecasts up to 16 days in advance of the arrival of high waters. These longer lead times provide the opportunity to save both lives and livelihoods. With sufficient advance notice, for example, farmers can harvest a threatened rice crop or move vulnerable livestock to higher ground. Importantly, the forecasts not only predict future water levels but indicate the level of confidence in each forecast. Knowing whether the probability of a danger-level flood is 10 percent or 90 percent helps people to decide what, if any, action to take. With respect to efforts in general preparedness and resilience building, we also present a recent flood risk assessment, and how it provides, for the first time, a numbers-based view of the impacts of different size floods across the Ganges basin. The findings help identify priority areas for tackling flood risks (for

  20. Regional flood impact assessment for Kiel and Eckernförde, Germany

    Science.gov (United States)

    Shustikova, Iuliia; Viavattene, Christophe; Seiß, Guntram

    2017-04-01

    It is well-observed that extreme flood events bring considerable destruction to coastal communities. The estimates of damage increases when direct and indirect losses are both considered in the assessment. This study applied the INtegrated DisRuption Assessment (INDRA) model which is designed to estimate and compare not only tangible but also intangible losses such as risk to life, recovery mechanisms and household displacement. Multi-criteria analysis (MCA) was performed in order to compare hotspots of high flood risk on the regional scale and detect which impact indicators influence results the most. INDRA allowed assessing the following impact indicators: direct damages to buildings and roads, transport disruption, risk to life and financial recovery mechanisms of private households and businesses. The focus was on two hotspots of flood risk, where direct and indirect impacts from 200 years flood were assessed and analyzed in terms of relative importance to the region. The region here was defined as municipalities located on the Baltic Sea coast within the Schleswig-Holstein state, Germany. The hotspots are the towns of Kiel and Eckernförde. They are urban areas with a high concentration of people and assets, which previously experienced extreme flood events. From the performed investigation it was found out that modeled flood differently impacts Kiel and Eckernförde. The results produced by MCA show that the scores of direct and indirect damage are slightly higher in Eckernförde than in Kiel. Transport disruption is a compelling element in the performed regional impact assessment and demonstrated immense weight. Extreme events may pose significant direct and indirect impacts on the coastal roads, obstructing not only the access to important landmarks such as hospitals, train stations, harbors, etc. but also to contiguous municipalities. Yet, the analysis showed that other impact indicators are rather of local importance and would not cause vast damage on a

  1. Upstream structural management measures for an urban area flooding in Turkey

    Science.gov (United States)

    Akyurek, Z.; Bozoğlu, B.; Sürer, S.; Mumcu, H.

    2015-06-01

    In recent years, flooding has become an increasing concern across many parts of the world of both the general public and their governments. The climate change inducing more intense rainfall events occurring in short period of time lead flooding in rural and urban areas. In this study the flood modelling in an urbanized area, namely Samsun-Terme in Blacksea region of Turkey is performed. MIKE21 with flexible grid is used in 2-dimensional shallow water flow modelling. 1 × 1000-1 scaled maps with the buildings for the urbanized area and 1 × 5000-1 scaled maps for the rural parts are used to obtain DTM needed in the flood modelling. The bathymetry of the river is obtained from additional surveys. The main river passing through the urbanized area has a capacity of 500 m3 s-1 according to the design discharge obtained by simple ungauged discharge estimation depending on catchment area only. The upstream structural base precautions against flooding are modelled. The effect of four main upstream catchments on the flooding in the downstream urban area are modelled as different scenarios. It is observed that if the flow from the upstream catchments can be retarded through a detention pond constructed in one of the upstream catchments, estimated Q100 flood can be conveyed by the river without overtopping from the river channel. The operation of the upstream detention ponds and the scenarios to convey Q500 without causing flooding are also presented. Structural management measures to address changes in flood characteristics in water management planning are discussed.

  2. Flood Inundation Mapping and Management using RISAT-1 derived Flood Inundation Areas, Cartosat-1 DEM and a River Flow Model

    Science.gov (United States)

    Kuldeep, K.; Garg, P. K.; Garg, R. D.

    2017-12-01

    The frequent occurrence of repeated flood events in many regions of the world causing damage to human life and property has augmented the need for effective flood risk management. Microwave satellite data is becoming an indispensable asset for monitoring of many environmental and climatic applications as numerous space-borne synthetic aperture radar (SAR) sensors are offering the data with high spatial resolutions and multi-polarization capabilities. The implementation and execution of Flood mapping, monitoring and management applications has become easier with the availability of SAR data which has obvious advantages over optical data due to its all weather, day and night capabilities. In this study, the exploitation of the SAR dataset for hydraulic modelling and disaster management has been highlighted using feature extraction techniques for water area identification and water level extraction within the floodplain. The availability of high precision digital elevation model generated from the Cartosat-1 stereo pairs has enhanced the capability of retrieving the water depth maps by incorporating the SAR derived flood extent maps. This paper illustrates the flood event on June 2013 in Yamuna River, Haryana, India. The water surface profile computed by combining the topographic data with the RISAT-1 data accurately reflects the true water line. Water levels that were computed by carrying out the modelling using hydraulic model in HECRAS also suggest that the water surface profiles provided by the combined use of topographic data and SAR accurately reflect the true water line. The proposed approach has also been found better in extraction of inundation within vegetated areas.

  3. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, MERCED COUNTY, CALIFORNIA AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Floodplain Mapping/Redelineation study deliverables depict and quantify the flood risks for the study area. The primary risk classifications used are the...

  4. Neighbourhood Socio Economic Disadvantage Index’s Analysis of the Flood Disasters Area at East Jakarta in 1996 and 2016

    Science.gov (United States)

    Ranti Ristiani, Christina; Rokhmatuloh; Hernina, Revi

    2017-12-01

    Flood is one of natural disasters that have often happened in East Jakarta. Flood can give several negative impacts and it can affect all aspects of society lives such as economics, political, cultural, socials and others. East Jakarta is an urban area which continuously grows and establishes to become a rapid area. It can be seen from the highest population density in East Jakarta (BPS, 2016) and categorized into a region prone to flooding based on data Prone Flood Map in 1996 and 2016. The higher population exists in East Jakarta, the bigger possibility of the negative effects of disaster it gets. The negative impacts of flood disaster can affect societies especially with socio-economic disadvantage. One of the index to measure socio-economic disadvantage is NSDI (Neighbourhood socio-economic disadvantage index). However, to adjust indicators used in NSDI with Indonesia statistical data compatibility, it needs further assessment and evaluation. Therefore, this paper evaluates previous main indicators used in previous NSDI studies and improves with indicators which more suitable with statistical records in Indonesia. As a result, there will be improved 19 indicators to be used in NSDI, but the groups of indicators remain the same as previous namely; income, education, occupation, housing, and population.

  5. New challenges on uncertainty propagation assessment of flood risk analysis

    Science.gov (United States)

    Martins, Luciano; Aroca-Jiménez, Estefanía; Bodoque, José M.; Díez-Herrero, Andrés

    2016-04-01

    Natural hazards, such as floods, cause considerable damage to the human life, material and functional assets every year and around the World. Risk assessment procedures has associated a set of uncertainties, mainly of two types: natural, derived from stochastic character inherent in the flood process dynamics; and epistemic, that are associated with lack of knowledge or the bad procedures employed in the study of these processes. There are abundant scientific and technical literature on uncertainties estimation in each step of flood risk analysis (e.g. rainfall estimates, hydraulic modelling variables); but very few experience on the propagation of the uncertainties along the flood risk assessment. Therefore, epistemic uncertainties are the main goal of this work, in particular,understand the extension of the propagation of uncertainties throughout the process, starting with inundability studies until risk analysis, and how far does vary a proper analysis of the risk of flooding. These methodologies, such as Polynomial Chaos Theory (PCT), Method of Moments or Monte Carlo, are used to evaluate different sources of error, such as data records (precipitation gauges, flow gauges...), hydrologic and hydraulic modelling (inundation estimation), socio-demographic data (damage estimation) to evaluate the uncertainties propagation (UP) considered in design flood risk estimation both, in numerical and cartographic expression. In order to consider the total uncertainty and understand what factors are contributed most to the final uncertainty, we used the method of Polynomial Chaos Theory (PCT). It represents an interesting way to handle to inclusion of uncertainty in the modelling and simulation process. PCT allows for the development of a probabilistic model of the system in a deterministic setting. This is done by using random variables and polynomials to handle the effects of uncertainty. Method application results have a better robustness than traditional analysis

  6. How Confident can we be in Flood Risk Assessments?

    Science.gov (United States)

    Merz, B.

    2017-12-01

    Flood risk management should be based on risk analyses quantifying the risk and its reduction for different risk reduction strategies. However, validating risk estimates by comparing model simulations with past observations is hardly possible, since the assessment typically encompasses extreme events and their impacts that have not been observed before. Hence, risk analyses are strongly based on assumptions and expert judgement. This situation opens the door for cognitive biases, such as `illusion of certainty', `overconfidence' or `recency bias'. Such biases operate specifically in complex situations with many factors involved, when uncertainty is high and events are probabilistic, or when close learning feedback loops are missing - aspects that all apply to risk analyses. This contribution discusses how confident we can be in flood risk assessments, and reflects about more rigorous approaches towards their validation.

  7. Low cost, multiscale and multi-sensor application for flooded area mapping

    Directory of Open Access Journals (Sweden)

    D. Giordan

    2018-05-01

    Full Text Available Flood mapping and estimation of the maximum water depth are essential elements for the first damage evaluation, civil protection intervention planning and detection of areas where remediation is needed. In this work, we present and discuss a methodology for mapping and quantifying flood severity over floodplains. The proposed methodology considers a multiscale and multi-sensor approach using free or low-cost data and sensors. We applied this method to the November 2016 Piedmont (northwestern Italy flood. We first mapped the flooded areas at the basin scale using free satellite data from low- to medium-high-resolution from both the SAR (Sentinel-1, COSMO-Skymed and multispectral sensors (MODIS, Sentinel-2. Using very- and ultra-high-resolution images from the low-cost aerial platform and remotely piloted aerial system, we refined the flooded zone and detected the most damaged sector. The presented method considers both urbanised and non-urbanised areas. Nadiral images have several limitations, in particular in urbanised areas, where the use of terrestrial images solved this limitation. Very- and ultra-high-resolution images were processed with structure from motion (SfM for the realisation of 3-D models. These data, combined with an available digital terrain model, allowed us to obtain maps of the flooded area, maximum high water area and damaged infrastructures.

  8. Assessing uncertainty in SRTM elevations for global flood modelling

    Science.gov (United States)

    Hawker, L. P.; Rougier, J.; Neal, J. C.; Bates, P. D.

    2017-12-01

    The SRTM DEM is widely used as the topography input to flood models in data-sparse locations. Understanding spatial error in the SRTM product is crucial in constraining uncertainty about elevations and assessing the impact of these upon flood prediction. Assessment of SRTM error was carried out by Rodriguez et al (2006), but this did not explicitly quantify the spatial structure of vertical errors in the DEM, and nor did it distinguish between errors over different types of landscape. As a result, there is a lack of information about spatial structure of vertical errors of the SRTM in the landscape that matters most to flood models - the floodplain. Therefore, this study attempts this task by comparing SRTM, an error corrected SRTM product (The MERIT DEM of Yamazaki et al., 2017) and near truth LIDAR elevations for 3 deltaic floodplains (Mississippi, Po, Wax Lake) and a large lowland region (the Fens, UK). Using the error covariance function, calculated by comparing SRTM elevations to the near truth LIDAR, perturbations of the 90m SRTM DEM were generated, producing a catalogue of plausible DEMs. This allows modellers to simulate a suite of plausible DEMs at any aggregated block size above native SRTM resolution. Finally, the generated DEM's were input into a hydrodynamic model of the Mekong Delta, built using the LISFLOOD-FP hydrodynamic model, to assess how DEM error affects the hydrodynamics and inundation extent across the domain. The end product of this is an inundation map with the probability of each pixel being flooded based on the catalogue of DEMs. In a world of increasing computer power, but a lack of detailed datasets, this powerful approach can be used throughout natural hazard modelling to understand how errors in the SRTM DEM can impact the hazard assessment.

  9. GIS Analysis of Flood Vulnerable Areas In Benin- Owena River Basin, Nigeria

    Directory of Open Access Journals (Sweden)

    Adebayo Oluwasegun Hezekiah

    2017-07-01

    Full Text Available The frequency and intensity of flood disasters have become serious issues in the national development process of Nigeria as flood disasters have caused serious environmental damages, loss of human lives and other heavy economic losses;  putting the issue of disaster reduction and risk management higher on the policy agenda of affected governments, multilateral agencies and NGOs. The starting point of concrete flood disaster mitigation efforts is to identify the areas with higher risk levels and fashion out appropriate preventive and response mechanisms. This research paper explored the potentials of Geographic Information System (GIS in data capture, processing and analysis in identifying flood-prone areas for the purpose of planning for disaster mitigation and preparedness, using Benin-Owena river basin of Nigeria as a unit of analysis. The data used in this study were obtained from FORMECU and were entered and use to develop a flood risk information system. Analysis and capability of the developed system was illustrated and shown graphically. The research showed that over one thousand settlements harbouring over ten million people located in the study area are at grave risk of flooding.   Key words: Flood, Risk, Vulnerability, Geographical Information System (GIS, River -Basin

  10. Assessment of the spatial scaling behaviour of floods in the United Kingdom

    Science.gov (United States)

    Formetta, Giuseppe; Stewart, Elizabeth; Bell, Victoria

    2017-04-01

    Floods are among the most dangerous natural hazards, causing loss of life and significant damage to private and public property. Regional flood-frequency analysis (FFA) methods are essential tools to assess the flood hazard and plan interventions for its mitigation. FFA methods are often based on the well-known index flood method that assumes the invariance of the coefficient of variation of floods with drainage area. This assumption is equivalent to the simple scaling or self-similarity assumption for peak floods, i.e. their spatial structure remains similar in a particular, relatively simple, way to itself over a range of scales. Spatial scaling of floods has been evaluated at national scale for different countries such as Canada, USA, and Australia. According our knowledge. Such a study has not been conducted for the United Kingdom even though the standard FFA method there is based on the index flood assumption. In this work we present an integrated approach to assess of the spatial scaling behaviour of floods in the United Kingdom using three different methods: product moments (PM), probability weighted moments (PWM), and quantile analysis (QA). We analyse both instantaneous and daily annual observed maximum floods and performed our analysis both across the entire country and in its sub-climatic regions as defined in the Flood Studies Report (NERC, 1975). To evaluate the relationship between the k-th moments or quantiles and the drainage area we used both regression with area alone and multiple regression considering other explanatory variables to account for the geomorphology, amount of rainfall, and soil type of the catchments. The latter multiple regression approach was only recently demonstrated being more robust than the traditional regression with area alone that can lead to biased estimates of scaling exponents and misinterpretation of spatial scaling behaviour. We tested our framework on almost 600 rural catchments in UK considered as entire region and

  11. Comparison of 2D numerical models for river flood hazard assessment: simulation of the Secchia River flood in January, 2014

    Science.gov (United States)

    Shustikova, Iuliia; Domeneghetti, Alessio; Neal, Jeffrey; Bates, Paul; Castellarin, Attilio

    2017-04-01

    Hydrodynamic modeling of inundation events still brings a large array of uncertainties. This effect is especially evident in the models run for geographically large areas. Recent studies suggest using fully two-dimensional (2D) models with high resolution in order to avoid uncertainties and limitations coming from the incorrect interpretation of flood dynamics and an unrealistic reproduction of the terrain topography. This, however, affects the computational efficiency increasing the running time and hardware demands. Concerning this point, our study evaluates and compares numerical models of different complexity by testing them on a flood event that occurred in the basin of the Secchia River, Northern Italy, on 19th January, 2014. The event was characterized by a levee breach and consequent flooding of over 75 km2 of the plain behind the dike within 48 hours causing population displacement, one death and economic losses in excess of 400 million Euro. We test the well-established TELEMAC 2D, and LISFLOOD-FP codes, together with the recently launched HEC-RAS 5.0.3 (2D model), all models are implemented using different grid size (2-200 m) based on the 1 m digital elevation model resolution. TELEMAC is a fully 2D hydrodynamic model which is based on the finite-element or finite-volume approach. Whereas HEC-RAS 5.0.3 and LISFLOOD-FP are both coupled 1D-2D models. All models are calibrated against observed inundation extent and maximum water depths, which are retrieved from remotely sensed data and field survey reports. Our study quantitatively compares the three modeling strategies highlighting differences in terms of the ease of implementation, accuracy of representation of hydraulic processes within floodplains and computational efficiency. Additionally, we look into the different grid resolutions in terms of the results accuracy and computation time. Our study is a preliminary assessment that focuses on smaller areas in order to identify potential modeling schemes

  12. Capturing changes in flood risk with Bayesian approaches for flood damage assessment

    Science.gov (United States)

    Vogel, Kristin; Schröter, Kai; Kreibich, Heidi; Thieken, Annegret; Müller, Meike; Sieg, Tobias; Laudan, Jonas; Kienzler, Sarah; Weise, Laura; Merz, Bruno; Scherbaum, Frank

    2016-04-01

    Flood risk is a function of hazard as well as of exposure and vulnerability. All three components are under change over space and time and have to be considered for reliable damage estimations and risk analyses, since this is the basis for an efficient, adaptable risk management. Hitherto, models for estimating flood damage are comparatively simple and cannot sufficiently account for changing conditions. The Bayesian network approach allows for a multivariate modeling of complex systems without relying on expert knowledge about physical constraints. In a Bayesian network each model component is considered to be a random variable. The way of interactions between those variables can be learned from observations or be defined by expert knowledge. Even a combination of both is possible. Moreover, the probabilistic framework captures uncertainties related to the prediction and provides a probability distribution for the damage instead of a point estimate. The graphical representation of Bayesian networks helps to study the change of probabilities for changing circumstances and may thus simplify the communication between scientists and public authorities. In the framework of the DFG-Research Training Group "NatRiskChange" we aim to develop Bayesian networks for flood damage and vulnerability assessments of residential buildings and companies under changing conditions. A Bayesian network learned from data, collected over the last 15 years in flooded regions in the Elbe and Danube catchments (Germany), reveals the impact of many variables like building characteristics, precaution and warning situation on flood damage to residential buildings. While the handling of incomplete and hybrid (discrete mixed with continuous) data are the most challenging issues in the study on residential buildings, a similar study, that focuses on the vulnerability of small to medium sized companies, bears new challenges. Relying on a much smaller data set for the determination of the model

  13. Prehistoric floods on the Tennessee River—Assessing the use of stratigraphic records of past floods for improved flood-frequency analysis

    Science.gov (United States)

    Harden, Tessa M.; O'Connor, Jim E.

    2017-06-14

    Stratigraphic analysis, coupled with geochronologic techniques, indicates that a rich history of large Tennessee River floods is preserved in the Tennessee River Gorge area. Deposits of flood sediment from the 1867 peak discharge of record (460,000 cubic feet per second at Chattanooga, Tennessee) are preserved at many locations throughout the study area at sites with flood-sediment accumulation. Small exposures at two boulder overhangs reveal evidence of three to four other floods similar in size, or larger, than the 1867 flood in the last 3,000 years—one possibly as much or more than 50 percent larger. Records of floods also are preserved in stratigraphic sections at the mouth of the gorge at Williams Island and near Eaves Ferry, about 70 river miles upstream of the gorge. These stratigraphic records may extend as far back as about 9,000 years ago, giving a long history of Tennessee River floods. Although more evidence is needed to confirm these findings, a more in-depth comprehensive paleoflood study is feasible for the Tennessee River.

  14. Participatory flood vulnerability assessment: a multi-criteria approach

    Directory of Open Access Journals (Sweden)

    M. M. de Brito

    2018-01-01

    Full Text Available This paper presents a participatory multi-criteria decision-making (MCDM approach for flood vulnerability assessment while considering the relationships between vulnerability criteria. The applicability of the proposed framework is demonstrated in the municipalities of Lajeado and Estrela, Brazil. The model was co-constructed by 101 experts from governmental organizations, universities, research institutes, NGOs, and private companies. Participatory methods such as the Delphi survey, focus groups, and workshops were applied. A participatory problem structuration, in which the modellers work closely with end users, was used to establish the structure of the vulnerability index. The preferences of each participant regarding the criteria importance were spatially modelled through the analytical hierarchy process (AHP and analytical network process (ANP multi-criteria methods. Experts were also involved at the end of the modelling exercise for validation. The final product is a set of individual and group flood vulnerability maps. Both AHP and ANP proved to be effective for flood vulnerability assessment; however, ANP is preferred as it considers the dependences among criteria. The participatory approach enabled experts to learn from each other and acknowledge different perspectives towards social learning. The findings highlight that to enhance the credibility and deployment of model results, multiple viewpoints should be integrated without forcing consensus.

  15. Participatory flood vulnerability assessment: a multi-criteria approach

    Science.gov (United States)

    Madruga de Brito, Mariana; Evers, Mariele; Delos Santos Almoradie, Adrian

    2018-01-01

    This paper presents a participatory multi-criteria decision-making (MCDM) approach for flood vulnerability assessment while considering the relationships between vulnerability criteria. The applicability of the proposed framework is demonstrated in the municipalities of Lajeado and Estrela, Brazil. The model was co-constructed by 101 experts from governmental organizations, universities, research institutes, NGOs, and private companies. Participatory methods such as the Delphi survey, focus groups, and workshops were applied. A participatory problem structuration, in which the modellers work closely with end users, was used to establish the structure of the vulnerability index. The preferences of each participant regarding the criteria importance were spatially modelled through the analytical hierarchy process (AHP) and analytical network process (ANP) multi-criteria methods. Experts were also involved at the end of the modelling exercise for validation. The final product is a set of individual and group flood vulnerability maps. Both AHP and ANP proved to be effective for flood vulnerability assessment; however, ANP is preferred as it considers the dependences among criteria. The participatory approach enabled experts to learn from each other and acknowledge different perspectives towards social learning. The findings highlight that to enhance the credibility and deployment of model results, multiple viewpoints should be integrated without forcing consensus.

  16. The role of interactions along the flood process chain and implications for risk assessment

    Science.gov (United States)

    Vorogushyn, Sergiy; Apel, Heiko; Viet Nguyen, Dung; Guse, Björn; Kreibich, Heidi; Lüdtke, Stefan; Schröter, Kai; Merz, Bruno

    2017-04-01

    Floods with their manifold characteristics are shaped by various processes along the flood process chain - from triggering meteorological extremes through catchment and river network process down to impacts on societies. In flood risk systems numerous interactions and feedbacks along the process chain may occur which finally shape spatio-temporal flood patterns and determine the ultimate risk. In this talk, we review some important interactions in the atmosphere-catchment, river-dike-floodplain and vulnerability compartments of the flood risk system. We highlight the importance of spatial interactions for flood hazard and risk assessment. For instance, the role of spatial rainfall structure or wave superposition in river networks is elucidated with selected case studies. In conclusion, we show the limits of current methods in assessment of large-scale flooding and outline the approach to more comprehensive risk assessment based on our regional flood risk model (RFM) for Germany.

  17. Flood Mapping: Assessing the uncertainty associated with flood inundation modelling. A case study of the Mora River, Sweden

    OpenAIRE

    Åberg, Isabelle

    2017-01-01

    Expansion of cities and major infrastructure projects lead to changes in land use and river flows. The probability of flooding is expected to increase in the future as a result of these changes in combination with climate change. Hydraulic models can be used to obtain simulated water levels to investigate the risk of flooding and identify areas that might potentially be flooded due to climate change. Since a model is a simplification of the reality it is important to be aware of a model’s unc...

  18. Floods and climate: emerging perspectives for flood risk assessment and management

    NARCIS (Netherlands)

    Merz, B.; Aerts, J.C.J.H.; Arnbjerg-Nielsen, K.; Baldi, M.; Becker, A.; Bichet, A.; Blöschl, G.; Bouwer, L.M.; Brauer, A.; Cioffi, F.; Delgado, J.M.; Gocht, M.; Guzetti, F.; Harrigan, S.; Hirschboeck, K.; Kilsby, C.; Kron, W.; Kwon, H. -H.; Lall, U.; Merz, R.; Nissen, K.; Salvatti, P.; Swierczynski, T.; Ulbrich, U.; Viglione, A.; Ward, P.J.; Weiler, M.; Wilhelm, B.; Nied, M.

    2014-01-01

    Flood estimation and flood management have traditionally been the domain of hydrologists, water resources engineers and statisticians, and disciplinary approaches abound. Dominant views have been shaped; one example is the catchment perspective: floods are formed and influenced by the interaction of

  19. Applying the Flood Vulnerability Index as a Knowledge base for flood risk assessment

    NARCIS (Netherlands)

    Balica, S-F.

    2012-01-01

    Floods are one of the most common and widely distributed natural risks to life and property worldwide. An important part of modern flood risk management is to evaluate vulnerability to floods. This evaluation can be done only by using a parametric approach. Worldwide there is a need to enhance our

  20. The Impact of Changing Storage Area on Flood Magnitude and Occurrence

    Directory of Open Access Journals (Sweden)

    Kusumastuti D.I.

    2012-01-01

    Full Text Available This study focuses on the impact of combined catchment and storage upon flood occurrences and flood peaks. A significant factor that plays an important role of the combined catchment and storage is the ratio of contributing catchment area to storage area (AC/AS where the impact significantly shows increasing frequency of storage overflow and flood peaks with the increasing of AC/AS. Some case studies examined in this work, i.e. Way Pegadungan (Lampung, Sumatra and NagaraRiver (South Kalimantan catchments show similar behavior. Swamps located on the sides of downstream of Way Pegadungan as well as Nagara River act as storages during flood events. The dyke which was planned to be built increases the ratio of AC/AS significantly as storage area reduced considerably. This has an impact on flood peaks which can increase considerably. The improved understanding of these process controls will be useful in assisting the management of such catchments, particularly to assist in flood prevention and mitigation.

  1. Assessing flash flood vulnerability using a multi-vulnerability approach

    Directory of Open Access Journals (Sweden)

    Karagiorgos Konstantinos

    2016-01-01

    Full Text Available In the framework of flood risk assessment, while the understanding of hazard and exposure has significantly improved over the last years, knowledge on vulnerability remains one of the challenges. Current approaches in vulnerability research are characterised by a division between social scientists and natural scientists. In order to close this gap, we present an approach that combines information on physical and social vulnerability in order to merge information on the susceptibility of elements at risk and society. With respect to physical vulnerability, the study is based on local-scale vulnerability models using nonlinear regression approaches. Modified Weibull distributions were fit to the data in order to represent the relationship between process magnitude and degree of loss. With respect to social vulnerability we conducted a door-to-door survey which resulted in particular insights on flood risk awareness and resilience strategies of exposed communities. In general, both physical and social vulnerability were low in comparison with other European studies, which may result from (a specific building regulations in the four Mediterranean test sites as well as general design principles leading to low structural susceptibility of elements at risk, and (b relatively low social vulnerability of citizens exposed. As a result it is shown that a combination of different perspectives of vulnerability will lead to a better understanding of exposure and capacities in flood risk management.

  2. Potentially pathogenic free-living amoebae in some flood-affected areas during 2011 Chiang Mai flood.

    Science.gov (United States)

    Wannasan, Anchalee; Uparanukraw, Pichart; Songsangchun, Apichart; Morakote, Nimit

    2013-01-01

    The survey was carried out to investigate the presence of potentially pathogenic free-living amoebae (FLA) during flood in Chiang Mai, Thailand in 2011. From different crisis flood areas, seven water samples were collected and tested for the presence of amoebae using culture and molecular methods. By monoxenic culture, FLA were detected from all samples at 37 °C incubation. The FLA growing at 37 °C were morphologically identified as Acanthamoeba spp., Naegleria spp. and some unidentified amoebae. Only three samples (42.8%), defined as thermotolerant FLA, continued to grow at 42 °C. By molecular methods, two non-thermotolerant FlA were shown to have 99% identity to Acanthamoeba sp. and 98% identity to Hartmannella vermiformis while the two thermotolerant FLA were identified as Echinamoeba exundans (100% identity) and Hartmannella sp. (99% identity). This first report of the occurrence of FLA in water during the flood disaster will provide information to the public to be aware of potentially pathogenic FLA.

  3. A methodology for the assessment of flood hazards at the regional scale

    Science.gov (United States)

    Gallina, Valentina; Torresan, Silvia; Critto, Andrea; Zabeo, Alex; Semenzin, Elena; Marcomini, Antonio

    2013-04-01

    In recent years, the frequency of water-related disasters has increased and recent flood events in Europe (e.g. 2002 in Central Europe, 2007 in UK, 2010 in Italy) caused physical-environmental and socio-economic damages. Specifically, floods are the most threatening water-related disaster that affects humans, their lives and properties. Within the KULTURisk project (FP7) a Regional Risk Assessment (RRA) methodology is proposed to evaluate the benefits of risk prevention in terms of reduced environmental risks due to floods. The method is based on the KULTURisk framework and allows the identification and prioritization of targets (i.e. people, buildings, infrastructures, agriculture, natural and semi-natural systems, cultural heritages) and areas at risk from floods in the considered region by comparing the baseline scenario (i.e. current state) with alternative scenarios (i.e. where different structural and/or non-structural measures are planned). The RRA methodology is flexible and 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). The final aim of RRA is to help decision-makers in examining the possible environmental risks associated with uncertain future flood hazards and in identifying which prevention scenario could be the most suitable one. The RRA methodology employs Multi-Criteria Decision Analysis (MCDA functions) in order to integrate stakeholder preferences and experts judgments into the analysis. Moreover, Geographic Information Systems (GISs) are used to manage, process, analyze, and map data to facilitate the analysis and the information sharing with different experts and stakeholders. In order to characterize flood risks, the proposed methodology integrates the output of hydrodynamic models with the analysis of site-specific bio-geophysical and socio-economic indicators (e.g. slope of the territory, land cover

  4. Analysing the Effects of Flood-Resilience Technologies in Urban Areas Using a Synthetic Model Approach

    Directory of Open Access Journals (Sweden)

    Reinhard Schinke

    2016-11-01

    Full Text Available Flood protection systems with their spatial effects play an important role in managing and reducing flood risks. The planning and decision process as well as the technical implementation are well organized and often exercised. However, building-related flood-resilience technologies (FReT are often neglected due to the absence of suitable approaches to analyse and to integrate such measures in large-scale flood damage mitigation concepts. Against this backdrop, a synthetic model-approach was extended by few complementary methodical steps in order to calculate flood damage to buildings considering the effects of building-related FReT and to analyse the area-related reduction of flood risks by geo-information systems (GIS with high spatial resolution. It includes a civil engineering based investigation of characteristic properties with its building construction including a selection and combination of appropriate FReT as a basis for derivation of synthetic depth-damage functions. Depending on the real exposition and the implementation level of FReT, the functions can be used and allocated in spatial damage and risk analyses. The application of the extended approach is shown at a case study in Valencia (Spain. In this way, the overall research findings improve the integration of FReT in flood risk management. They provide also some useful information for advising of individuals at risk supporting the selection and implementation of FReT.

  5. SLR-induced changes on storm flooding in coastal areas: the role of accommodation space

    Science.gov (United States)

    Jiménez, Jose A.; Dockx, Stijn; Monbaliu, Jaak

    2015-04-01

    Most of existing predictions of climate-induce changes in coastal storminess in the Mediterranean indicate the absence of any significant increasing trend in neither wave height nor surge. However, this does not mean that magnitude and/or frequency of storm-induced coastal hazards will not be affected by climate change. Thus, sea level rise will induce a series of long-term changes in coastal areas that although not directly affecting storminess will interact with storm-induced processes and, thus, changing coastal storm risks. A typical approach to account SLR-induced effects on coastal inundation by storms is to modify present water level extreme climate by adding expected MWL increase. This implies to consider the coast as a static and passive system to SLR maintaining its configuration from actual to projected (rised) sea level and, as a result of this, the frequency of flood events should increase and, the magnitude of flooding associated to a probability of occurrence will also increase. This will only be realistic for really passive or rigid coasts. However, sandy coastlines will response to SLR and, thus, this approach should undervalue coastal resilience. Within this context, the main aim of this work is to propose a method to assess the effects of SLR on the magnitude of storm-induced coastal flooding on sandy coastlines taking into account their capacity of response. It combines the use of a inundation model (LISFLOOD-FP) for delineating the flood-prone area for given storm conditions and, a coastal module to account for SLR-induced changes in the coastal fringe. The method assumes an equilibrium-type coastal response to SLR which, ideally, implies that the beach profile will be reconstructed under the new higher water level, in such a way that the relative beach configuration will be the same. However, this should only be possible provided there is enough accommodation space in the hinterland. In most of developed coasts, the existence of human built

  6. Near Real-Time Flood Monitoring and Impact Assessment Systems. Chapter 6; [Case Study: 2011 Flooding in Southeast Asia

    Science.gov (United States)

    Ahamed, Aakash; Bolten, John; Doyle, Colin; Fayne, Jessica

    2016-01-01

    Floods are the costliest natural disaster, causing approximately 6.8 million deaths in the twentieth century alone. Worldwide economic flood damage estimates in 2012 exceed $19 Billion USD. Extended duration floods also pose longer term threats to food security, water, sanitation, hygiene, and community livelihoods, particularly in developing countries. Projections by the Intergovernmental Panel on Climate Change (IPCC) suggest that precipitation extremes, rainfall intensity, storm intensity, and variability are increasing due to climate change. Increasing hydrologic uncertainty will likely lead to unprecedented extreme flood events. As such, there is a vital need to enhance and further develop traditional techniques used to rapidly assess flooding and extend analytical methods to estimate impacted population and infrastructure. Measuring flood extent in situ is generally impractical, time consuming, and can be inaccurate. Remotely sensed imagery acquired from space-borne and airborne sensors provides a viable platform for consistent and rapid wall-to-wall monitoring of large flood events through time. Terabytes of freely available satellite imagery are made available online each day by NASA, ESA, and other international space research institutions. Advances in cloud computing and data storage technologies allow researchers to leverage these satellite data and apply analytical methods at scale. Repeat-survey earth observations help provide insight about how natural phenomena change through time, including the progression and recession of floodwaters. In recent years, cloud-penetrating radar remote sensing techniques (e.g., Synthetic Aperture Radar) and high temporal resolution imagery platforms (e.g., MODIS and its 1-day return period), along with high performance computing infrastructure, have enabled significant advances in software systems that provide flood warning, assessments, and hazard reduction potential. By incorporating social and economic data

  7. Surging Seas Risk Finder: A Tool for Local-Scale Flood Risk Assessments in Coastal Cities

    Science.gov (United States)

    Kulp, S. A.; Strauss, B.

    2015-12-01

    Local decision makers in coastal cities require accurate, accessible, and thorough assessments of flood exposure risk within their individual municipality, in their efforts to mitigate against damage due to future sea level rise. To fill this need, we have developed Climate Central's Surging Seas Risk Finder, an interactive data toolkit which presents our sea level rise and storm surge analysis for every coastal town, city, county, and state within the USA. Using this tool, policy makers can easily zoom in on their local place of interest to receive a detailed flood risk assessment, which synthesizes a wide range of features including total population, socially vulnerable population, housing, property value, road miles, power plants, schools, hospitals, and many other critical facilities. Risk Finder can also be used to identify specific points of interest in danger of exposure at different flood levels. Additionally, this tool provides localized storm surge probabilities and sea level rise projections at tidal gauges along the coast, so that users can quickly understand the risk of flooding in their area over the coming decades.

  8. Detection and assessment of flood susceptible irrigation networks in Licab, Nueva Ecija, Philippines using LiDAR DTM

    Science.gov (United States)

    Alberto, R. T.; Hernando, P. J. C.; Tagaca, R. C.; Celestino, A. B.; Palado, G. C.; Camaso, E. E.; Damian, G. B.

    2017-09-01

    Climate change has wide-ranging effects on the environment and socio-economic and related sectors which includes water resources, agriculture and food security, human health, terrestrial ecosystems, coastal zones and biodiversity. Farmers are under pressure to the changing weather and increasing unpredictable water supply. Because of rainfall deficiencies, artificial application of water has been made through irrigation. Irrigation is a basic determinant of agriculture because its inadequacies are the most powerful constraints on the increase of agricultural production. Irrigation networks are permanent and temporary conduits that supply water to agricultural areas from an irrigation source. Detection of irrigation networks using LiDAR DTM, and flood susceptible assessment of irrigation networks could give baseline information on the development and management of sustainable agriculture. Map Gully Depth (MGD) in Whitebox GAT was used to generate the potential irrigation networks. The extracted MGD was overlaid in ArcGIS as guide in the digitization of potential irrigation networks. A flood hazard map was also used to identify the flood susceptible irrigation networks in the study area. The study was assessed through field validation of points which were generated using random sampling method. Results of the study showed that most of the detected irrigation networks have low to moderate susceptibility to flooding while the rest have high susceptibility to flooding which is due to shifting weather. These irrigation networks may cause flood when it overflows that could also bring huge damage to rice and other agricultural areas.

  9. Enhanced Effects of Flood Disasters Due to Hillside Development in Urban Areas

    Directory of Open Access Journals (Sweden)

    Wei-Hsien Teng

    2013-02-01

    Full Text Available In recent years, the Taiwan government has established a number of flood control facilities such as dikes, pumping stations and drainage systems to effectively reduce downstream flooding. However, with continued development and urbanization of catchment areas, the original designs of most flood control facilities have become outdated. Hillside lands in the upper and middle reaches of river basins have undergone urban development through unsound engineering practices, paving the way for heavy downstream flooding. Therefore, proper river basin management should include both upstream and downstream sides. The main purpose of the paper is to simulate non-urban inundation areas with various degrees of development (0%, 10%, 20%, 40% and 60%, over two different return periods of 25 years and 200 years, for intensive rainfall events in the Shi-Chi District, Taiwan. Through hydrological analysis and numerical simulations of inundation, quantitative data on inundation potential have been established based on the land development conditions along the hillsides on the upper and middle reaches of the Keelung River Basin. The simulated results show that the increase in the extent of land development in the upper reaches causes an increase in the area and depth of inundation, resulting in an increased risk of flooding in downstream areas. If the land-use policy makers in the upper reaches of the river basin’s hillsides do not properly manage the land development, the risk of flooding in downstream areas will increase. In such an event, the policy makers should first review the situation to understand the problem with the consideration of this study. Thus, proper development and flood mitigation in hillsides can be established.

  10. Quantification of flood risk mitigation benefits: A building-scale damage assessment through the RASOR platform.

    Science.gov (United States)

    Arrighi, Chiara; Rossi, Lauro; Trasforini, Eva; Rudari, Roberto; Ferraris, Luca; Brugioni, Marcello; Franceschini, Serena; Castelli, Fabio

    2018-02-01

    Flood risk mitigation usually requires a significant investment of public resources and cost-effectiveness should be ensured. The assessment of the benefits of hydraulic works requires the quantification of (i) flood risk in absence of measures, (ii) risk in presence of mitigation works, (iii) investments to achieve acceptable residual risk. In this work a building-scale is adopted to estimate direct tangible flood losses to several building classes (e.g. residential, industrial, commercial, etc.) and respective contents, exploiting various sources of public open data in a GIS environment. The impact simulations for assigned flood hazard scenarios are computed through the RASOR platform which allows for an extensive characterization of the properties and their vulnerability through libraries of stage-damage curves. Recovery and replacement costs are estimated based on insurance data, market values and socio-economic proxies. The methodology is applied to the case study of Florence (Italy) where a system of retention basins upstream of the city is under construction to reduce flood risk. Current flood risk in the study area (70 km 2 ) is about 170 Mio euros per year without accounting for people, infrastructures, cultural heritage and vehicles at risk. The monetary investment in the retention basins is paid off in about 5 years. However, the results show that although hydraulic works are cost-effective, a significant residual risk has to be managed and the achievement of the desired level of acceptable risk would require about 1 billion euros of investments. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Quantifying the effect of autonomous adaptation to global river flood projections: application to future flood risk assessments

    Science.gov (United States)

    Kinoshita, Youhei; Tanoue, Masahiro; Watanabe, Satoshi; Hirabayashi, Yukiko

    2018-01-01

    This study represents the first attempt to quantify the effects of autonomous adaptation on the projection of global flood hazards and to assess future flood risk by including this effect. A vulnerability scenario, which varies according to the autonomous adaptation effect for conventional disaster mitigation efforts, was developed based on historical vulnerability values derived from flood damage records and a river inundation simulation. Coupled with general circulation model outputs and future socioeconomic scenarios, potential future flood fatalities and economic loss were estimated. By including the effect of autonomous adaptation, our multimodel ensemble estimates projected a 2.0% decrease in potential flood fatalities and an 821% increase in potential economic losses by 2100 under the highest emission scenario together with a large population increase. Vulnerability changes reduced potential flood consequences by 64%-72% in terms of potential fatalities and 28%-42% in terms of potential economic losses by 2100. Although socioeconomic changes made the greatest contribution to the potential increased consequences of future floods, about a half of the increase of potential economic losses was mitigated by autonomous adaptation. There is a clear and positive relationship between the global temperature increase from the pre-industrial level and the estimated mean potential flood economic loss, while there is a negative relationship with potential fatalities due to the autonomous adaptation effect. A bootstrapping analysis suggests a significant increase in potential flood fatalities (+5.7%) without any adaptation if the temperature increases by 1.5 °C-2.0 °C, whereas the increase in potential economic loss (+0.9%) was not significant. Our method enables the effects of autonomous adaptation and additional adaptation efforts on climate-induced hazards to be distinguished, which would be essential for the accurate estimation of the cost of adaptation to

  12. Dynamic building risk assessment theoretic model for rainstorm-flood utilization ABM and ABS

    Science.gov (United States)

    Lai, Wenze; Li, Wenbo; Wang, Hailei; Huang, Yingliang; Wu, Xuelian; Sun, Bingyun

    2015-12-01

    Flood is one of natural disasters with the worst loss in the world. It needs to assess flood disaster risk so that we can reduce the loss of flood disaster. Disaster management practical work needs the dynamic risk results of building. Rainstorm flood disaster system is a typical complex system. From the view of complex system theory, flood disaster risk is the interaction result of hazard effect objects, rainstorm flood hazard factors, and hazard environments. Agent-based modeling (ABM) is an important tool for complex system modeling. Rainstorm-flood building risk dynamic assessment method (RFBRDAM) was proposed using ABM in this paper. The interior structures and procedures of different agents in proposed meth had been designed. On the Netlogo platform, the proposed method was implemented to assess the building risk changes of the rainstorm flood disaster in the Huaihe River Basin using Agent-based simulation (ABS). The results indicated that the proposed method can dynamically assess building risk of the whole process for the rainstorm flood disaster. The results of this paper can provide one new approach for flood disaster building risk dynamic assessment and flood disaster management.

  13. Assessment of big floods in the Eastern Black Sea Basin of Turkey.

    Science.gov (United States)

    Yüksek, Ömer; Kankal, Murat; Üçüncü, Osman

    2013-01-01

    In this study, general knowledge and some details of the floods in Eastern Black Sea Basin of Turkey are presented. Brief hydro-meteorological analysis of selected nine floods and detailed analysis of the greatest flood are given. In the studied area, 51 big floods have taken place between 1955-2005 years, causing 258 deaths and nearly US $500,000,000 of damage. Most of the floods have occurred in June, July and August. It is concluded that especially for the rainstorms that have caused significantly damages, the return periods of the rainfall heights and resultant flood discharges have gone up to 250 and 500 years, respectively. A general agreement is observed between the return periods of rains and resultant floods. It is concluded that there has been no significant climate change to cause increases in flood harms. The most important human factors to increase the damage are determined as wrong and illegal land use, deforestation and wrong urbanization and settlement, psychological and technical factors. Some structural and non-structural measures to mitigate flood damages are also included in the paper. Structural measures include dykes and flood levees. Main non-structural measures include flood warning system, modification of land use, watershed management and improvement, flood insurance, organization of flood management studies, coordination between related institutions and education of the people and informing of the stakeholders.

  14. DEM-based Approaches for the Identification of Flood Prone Areas

    Science.gov (United States)

    Samela, Caterina; Manfreda, Salvatore; Nardi, Fernando; Grimaldi, Salvatore; Roth, Giorgio; Sole, Aurelia

    2013-04-01

    The remarkable number of inundations that caused, in the last decades, thousands of deaths and huge economic losses, testifies the extreme vulnerability of many Countries to the flood hazard. As a matter of fact, human activities are often developed in the floodplains, creating conditions of extremely high risk. Terrain morphology plays an important role in understanding, modelling and analyzing the hydraulic behaviour of flood waves. Research during the last 10 years has shown that the delineation of flood prone areas can be carried out using fast methods that relay on basin geomorphologic features. In fact, the availability of new technologies to measure surface elevation (e.g., GPS, SAR, SAR interferometry, RADAR and LASER altimetry) has given a strong impulse to the development of Digital Elevation Models (DEMs) based approaches. The identification of the dominant topographic controls on the flood inundation process is a critical research question that we try to tackle with a comparative analysis of several techniques. We reviewed four different approaches for the morphological characterization of a river basin with the aim to provide a description of their performances and to identify their range of applicability. In particular, we explored the potential of the following tools. 1) The hydrogeomorphic method proposed by Nardi et al. (2006) which defines the flood prone areas according to the water level in the river network through the hydrogeomorphic theory. 2) The linear binary classifier proposed by Degiorgis et al. (2012) which allows distinguishing flood-prone areas using two features related to the location of the site under exam with respect to the nearest hazard source. The two features, proposed in the study, are the length of the path that hydrologically connects the location under exam to the nearest element of the drainage network and the difference in elevation between the cell under exam and the final point of the same path. 3) The method by

  15. Real-time flood forecasts & risk assessment using a possibility-theory based fuzzy neural network

    Science.gov (United States)

    Khan, U. T.

    2016-12-01

    Globally floods are one of the most devastating natural disasters and improved flood forecasting methods are essential for better flood protection in urban areas. Given the availability of high resolution real-time datasets for flood variables (e.g. streamflow and precipitation) in many urban areas, data-driven models have been effectively used to predict peak flow rates in river; however, the selection of input parameters for these types of models is often subjective. Additionally, the inherit uncertainty associated with data models along with errors in extreme event observations means that uncertainty quantification is essential. Addressing these concerns will enable improved flood forecasting methods and provide more accurate flood risk assessments. In this research, a new type of data-driven model, a quasi-real-time updating fuzzy neural network is developed to predict peak flow rates in urban riverine watersheds. A possibility-to-probability transformation is first used to convert observed data into fuzzy numbers. A possibility theory based training regime is them used to construct the fuzzy parameters and the outputs. A new entropy-based optimisation criterion is used to train the network. Two existing methods to select the optimum input parameters are modified to account for fuzzy number inputs, and compared. These methods are: Entropy-Wavelet-based Artificial Neural Network (EWANN) and Combined Neural Pathway Strength Analysis (CNPSA). Finally, an automated algorithm design to select the optimum structure of the neural network is implemented. The overall impact of each component of training this network is to replace the traditional ad hoc network configuration methods, with one based on objective criteria. Ten years of data from the Bow River in Calgary, Canada (including two major floods in 2005 and 2013) are used to calibrate and test the network. The EWANN method selected lagged peak flow as a candidate input, whereas the CNPSA method selected lagged

  16. [The assessment of vulnerability to floods in Guangdong province at district level].

    Science.gov (United States)

    Zhu, Qi; Liu, Tao; Zhang, Yong-hui; Luo, Yuan; Wei, Yao; Xiao, Jian-peng; Zeng, Si-qing; Ma, Wen-jun

    2012-11-01

    To evaluate the vulnerability to floods in Guangdong province at district level. Data were collected from the sixth census, the 2010 Statistical Yearbook of Guangdong, the 2010 Health Statistics Yearbook of Guangdong and China Disease Prevention and Control information systems, etc. The weight of each indicator was determined based on subjective method and objective method respectively; and finally the results of the two methods were compared. 13 indicators were selected for the assessment of vulnerability to floods, including 6 sensitivity indicators, 5 adaptability indicators and 2 exposure indicators. Indicators with large weight (subjective weight/objective weight) were the proportion of population older than 65 years old (0.31/0.30), the proportion of population older than 65 years old (0.16/0.23), infant mortality rate (0.18/0.20), the total Gross Domestic Product (GDP) per capita (0.33/0.21), the proportion of illiterate in the population older than 15 years old (0.19/0.28), history frequency of floods (0.75/0.75). The mean vulnerability index (VI) calculated by subjective method was 0.35 with the standard deviation of 0.10; the mean vulnerability index calculated by objective method was 0.31 with the standard deviation of 0.08. The two weighting methods showed consistent results of vulnerability index (ICC = 0.975, P 0.50 or objective VI > 0.40 should pay more attention to floods, including parts of the coastal areas, Beijiang River Basin, the eastern tributary area of Dongjiang River and the northern part of Pearl River Delta. Dapu district of Meizhou (0.55/0.45), Dianbai district and Maogang district of Maoming (0.54/0.48) were most vulnerable. Districts of Heyuan, Dongguan, Zhaoqing and Huizhou were less vulnerable, Yuancheng district of Heyuan showed least vulnerable to floods (0.15/0.12) followed by Dongguan (0.18/0.16), Duanzhou district (0.18/0.16) and Guangning (0.17/0.15) district of Zhaoqing. The score of indicators differed among different level

  17. An assessment of flood vulnerability in Khyber Pukhtunkhwa province of Pakistan

    Directory of Open Access Journals (Sweden)

    Said Qasim

    2017-02-01

    Full Text Available In this research we have attempted to measure vulnerability of the communities living in the flood prone area of Khyber Pukhtunkhwa province of Pakistan. Extensive literature review was conducted to identify the flood vulnerability indicators. Primary data were used to achieve the objective of this study. Questionnaires were used to collect the primary data from the selected households and from the director of Centre for Disaster Preparedness and Management. Subjective assessment technique was used to allocate weights to the selected indicators of vulnerability. A sample size of 280 respondents was taken from three selected locations of Charsadda, Nowshera and Peshawar. Simple random sampling was employed for the selection of respondents. Results revealed that overall vulnerability as well as component vulnerability for the selected locations was very high. The study therefore recommends preparedness, provision of funds for building houses with flood resistant materials and building houses in safer places. There is also a need for enhancing the adaptive capacities of the concerned communities through their socio-economic uplift. Implementation of these policies would lower the vulnerability of the communities to flood disasters.

  18. Self-Reported and FEMA Flood Exposure Assessment after Hurricane Sandy: Association with Mental Health Outcomes.

    Directory of Open Access Journals (Sweden)

    Wil Lieberman-Cribbin

    Full Text Available Hurricane Sandy caused extensive physical and economic damage; the long-term mental health consequences are unknown. Flooding is a central component of hurricane exposure, influencing mental health through multiple pathways that unfold over months after flooding recedes. Here we assess the concordance in self-reported and Federal Emergency Management (FEMA flood exposure after Hurricane Sandy and determine the associations between flooding and anxiety, depression, and post-traumatic stress disorder (PTSD. Self-reported flood data and mental health symptoms were obtained through validated questionnaires from New York City and Long Island residents (N = 1231 following Sandy. Self-reported flood data was compared to FEMA data obtained from the FEMA Modeling Task Force Hurricane Sandy Impact Analysis. Multivariable logistic regressions were performed to determine the relationship between flooding exposure and mental health outcomes. There were significant discrepancies between self-reported and FEMA flood exposure data. Self-reported dichotomous flooding was positively associated with anxiety (ORadj: 1.5 [95% CI: 1.1-1.9], depression (ORadj: 1.7 [1.3-2.2], and PTSD (ORadj: 2.5 [1.8-3.4], while self-reported continuous flooding was associated with depression (ORadj: 1.1 [1.01-1.12] and PTSD (ORadj: 1.2 [1.1-1.2]. Models with FEMA dichotomous flooding (ORadj: 2.1 [1.5-2.8] or FEMA continuous flooding (ORadj: 1.1 [1.1-1.2] were only significantly associated with PTSD. Associations between mental health and flooding vary according to type of flood exposure measure utilized. Future hurricane preparedness and recovery efforts must integrate micro and macro-level flood exposures in order to accurately determine flood exposure risk during storms and realize the long-term importance of flooding on these three mental health symptoms.

  19. Economic Assessment of Flood Control Facilities under Climate Uncertainty: A Case of Nakdong River, South Korea

    Directory of Open Access Journals (Sweden)

    Kyeongseok Kim

    2018-01-01

    Full Text Available Climate change contributes to enhanced flood damage that has been increasing for the last several decades. Understanding climate uncertainties improves adaptation strategies used for investment in flood control facilities. This paper proposes an investment decision framework for one flood zone to cope with future severe climate impacts. This framework can help policy-makers investigate the cost of future damage and conduct an economic assessment using real options under future climate change scenarios. The proposed methodology provides local municipalities with an adaptation strategy for flood control facilities in a flood zone. Using the proposed framework, the flood prevention facilities in the Nakdong River Basin of South Korea was selected as a case study site to analyze the economic assessment of the investments for flood control facilities. Using representative concentration pathway (RCP climate scenarios, the cost of future flood damage to 23 local municipalities was calculated, and investment strategies for adaptation were analyzed. The project option value was determined by executing an option to invest in an expansion that would adapt to floods under climate change. The results of the case study showed that the proposed flood facilities are economically feasible under both scenarios used. The framework is anticipated to present guidance for establishing investment strategies for flood control facilities of a flood zone in multiple municipalities’ settings.

  20. An Integrated Modelling Framework to Assess Flood Risk under Urban Development and Changing Climate

    DEFF Research Database (Denmark)

    that combines a model for the socio-economic development of cities (DANCE4WATER) with an urban flood model. The urban flood model is a 1D-2D spatially distributed hydrologic and hydraulic model that, for a given urban layout, simulates flow in the sewer system and the surface flow in the catchment (MIKE FLOOD......). The socio-economic model computes urban layouts that are transferred to the hydraulic model in the form of changes of impervious area and potential flow paths on the surface. Estimates of flood prone areas, as well as the expected annual damage due to flooding, are returned to the socio-economic model...... as an input for further refinement of the scenarios for the urban development. Our results in an Australian case study suggest that urban development is a major driver for flood risk and vice versa that flood risk can be significantly reduced if it is accounted for in the development of the cities...

  1. Assessment of Remote Sensing Products and Hydrologic Simulation of the 2016 Louisiana Flood in the Amite River Basin

    Science.gov (United States)

    Gao, S.; Bilskie, M. V.; Hagen, S. C.; Braud, D.

    2017-12-01

    Riverine and coastal flooding are one of the most common environmental hazards that affect millions of people around the world. For example, in August 2016, a slow-moving upper level low-pressure system with a high amount of atmospheric moisture brought heavy rains from August 11 to August 13. The torrential downpours led to widespread flash flooding and river flooding across multiple parishes in Southeast Louisiana and Southwest Mississippi (NWS, 2016; Watson et al., 2017). Precipitation totals as high as 26 inches were recorded during the two-day event. A Louisiana Economic Development report documented that the state of Louisiana suffered more than eight billion dollars in damage from the catastrophic flooding (LED, 2016). According to the National Weather Service (NWS) in New Orleans, the rainfall caused the Amite River, Comite River, Tangipahoa River and Tickfaw River to rise to record-setting levels. Some of the most serious flooding occurred along the Amite River, which runs between Baton Rouge and the nearby city of Denham Springs, and has its headwaters in southwestern Mississippi and drains into Lake Maurepas (Mossa et al., 1997). To develop an understanding of the driving mechanisms that caused the catastrophic flooding a campaign was initiated to collect and rigorously examine all possible remote sensing products in order to derive the flooding extent and depth within the Amite River basin. In addition, a Soil and Water Assessment Tool (SWAT) has been developed for the Amite River watershed to simulate runoff from the 2016 Louisiana flood event. The developed and assimilated remote sensing and modeling products will enhance understanding of the hydrological processes within the Amite River basin. This will provide further insight into conceptualization of flood risk across river deltas that are vulnerable to both riverine and coastal flooding. Reference:LED. (2016). The economic impact of the august 2016 floods on the state of Louisiana. Mossa, J., & Mc

  2. Urban Flood Risk Assessment Under Uncertain Conditions and Scarce Information

    Science.gov (United States)

    Rodríguez-Gaviria, E. M.; Botero-Fernandez, V.

    2015-12-01

    Flood risk management in small urban areas in Colombia has a great degree of uncertainty due to the low availability and quality of data, the non-existent personnel qualified in the collection and processing of data, and the insufficient information to evaluate the risk and vulnerability. It is because of this that two methods are developed: one for the generation of flood threat maps for different return periods combining historical, geomorphological, and hydrological hydraulic methods assisted by remote sensors and SIG through the use of data acquired through field campaigns, official hydrological networks, orthophotos, multitemporal topographic maps, and ASTER, STRM, and LiDAR images. And another method in which categorical variables are established, linking local physical, social, economical, environmental and political-institutional factors that are explored through different media such as reports, news, databases, transects, interviews, community workshops, and surveys conducted at homes. Such variables were included within an analysis of multiple correspondence to conduct a descriptive study of the exposure, susceptibility, and capacity conditions and to create a vulnerability index that was spatially plotted spatially on maps. The uncertainty is reduced in the measure in which local knowledge is used as a source of information acquisition, of validation of what already exists, and of calibration of the proposed methods. This research was applied to the urban centers of Caucasia (Antioquia) and Plato (Magdalena), which have been historically affected by slow flooding of the Magdalena and Cauca river, it being especially useful in the selection of best alternatives for risk management, planning for development, and land use management, with the possibility of replicating it to benefit other municipalities that experience the same reality.

  3. An influence diagram for urban flood risk assessment through pluvial flood hazards under non-stationary conditions

    DEFF Research Database (Denmark)

    Åström, Helena Lisa Alexandra; Friis Hansen, P.; Garrè, Luca

    2014-01-01

    Urban flooding introduces significant risk to society. Non-stationarity leads to increased uncertainty and this is challenging to include in actual decision-making. The primary objective of this study was to develop a risk assessment and decision support framework for pluvial urban flood risk under...... non-stationary conditions using an influence diagram (ID) which is a Bayesian network (BN) extended with decision and utility nodes. Non-stationarity is considered to be the influence of climate change where extreme precipitation patterns change over time. The overall risk is quantified in monetary...... terms expressed as expected annual damage. The network is dynamic in as much as it assesses risk at different points in time. The framework provides means for decision-makers to assess how different decisions on flood adaptation affect the risk now and in the future. The result from the ID was extended...

  4. Assessing the Impacts of Flooding Caused by Extreme Rainfall Events Through a Combined Geospatial and Numerical Modeling Approach

    Science.gov (United States)

    Santillan, J. R.; Amora, A. M.; Makinano-Santillan, M.; Marqueso, J. T.; Cutamora, L. C.; Serviano, J. L.; Makinano, R. M.

    2016-06-01

    In this paper, we present a combined geospatial and two dimensional (2D) flood modeling approach to assess the impacts of flooding due to extreme rainfall events. We developed and implemented this approach to the Tago River Basin in the province of Surigao del Sur in Mindanao, Philippines, an area which suffered great damage due to flooding caused by Tropical Storms Lingling and Jangmi in the year 2014. The geospatial component of the approach involves extraction of several layers of information such as detailed topography/terrain, man-made features (buildings, roads, bridges) from 1-m spatial resolution LiDAR Digital Surface and Terrain Models (DTM/DSMs), and recent land-cover from Landsat 7 ETM+ and Landsat 8 OLI images. We then used these layers as inputs in developing a Hydrologic Engineering Center Hydrologic Modeling System (HEC HMS)-based hydrologic model, and a hydraulic model based on the 2D module of the latest version of HEC River Analysis System (RAS) to dynamically simulate and map the depth and extent of flooding due to extreme rainfall events. The extreme rainfall events used in the simulation represent 6 hypothetical rainfall events with return periods of 2, 5, 10, 25, 50, and 100 years. For each event, maximum flood depth maps were generated from the simulations, and these maps were further transformed into hazard maps by categorizing the flood depth into low, medium and high hazard levels. Using both the flood hazard maps and the layers of information extracted from remotely-sensed datasets in spatial overlay analysis, we were then able to estimate and assess the impacts of these flooding events to buildings, roads, bridges and landcover. Results of the assessments revealed increase in number of buildings, roads and bridges; and increase in areas of land-cover exposed to various flood hazards as rainfall events become more extreme. The wealth of information generated from the flood impact assessment using the approach can be very useful to the

  5. 44 CFR 65.5 - Revision to special hazard area boundaries with no change to base flood elevation determinations.

    Science.gov (United States)

    2010-10-01

    ... zones and floodways) it may be feasible to elevate areas with engineered earthen fill above the base... area boundaries with no change to base flood elevation determinations. 65.5 Section 65.5 Emergency... § 65.5 Revision to special hazard area boundaries with no change to base flood elevation determinations...

  6. Imagining flood futures: risk assessment and management in practice.

    Science.gov (United States)

    Lane, Stuart N; Landström, Catharina; Whatmore, Sarah J

    2011-05-13

    The mantra that policy and management should be 'evidence-based' is well established. Less so are the implications that follow from 'evidence' being predictions of the future (forecasts, scenarios, horizons) even though such futures define the actions taken today to make the future sustainable. Here, we consider the tension between 'evidence', reliable because it is observed, and predictions of the future, unobservable in conventional terms. For flood risk management in England and Wales, we show that futures are actively constituted, and so imagined, through 'suites of practices' entwining policy, management and scientific analysis. Management has to constrain analysis because of the many ways in which flood futures can be constructed, but also because of commitment to an accounting calculus, which requires risk to be expressed in monetary terms. It is grounded in numerical simulation, undertaken by scientific consultants who follow policy/management guidelines that define the futures to be considered. Historical evidence is needed to deal with process and parameter uncertainties and the futures imagined are tied to pasts experienced. Reliance on past events is a challenge for prediction, given changing probability (e.g. climate change) and consequence (e.g. development on floodplains). So, risk management allows some elements of risk analysis to become unstable (notably in relation to climate change) but forces others to remain stable (e.g. invoking regulation to prevent inappropriate floodplain development). We conclude that the assumed separation of risk assessment and management is false because the risk calculation has to be defined by management. Making this process accountable requires openness about the procedures that make flood risk analysis more (or less) reliable to those we entrust to produce and act upon them such that, unlike the 'pseudosciences', they can be put to the test of public interrogation by those who have to live with their consequences

  7. Prioritising watersheds on the basis of regional flood susceptibility and vulnerability in mountainous areas through the use of indicators

    Science.gov (United States)

    Rogelis, Carolina; Werner, Micha

    2013-04-01

    Settlements in peri-urban areas of many cities in mountainous areas such as in the Andes are susceptible to hazards such as flash floods and debris flows. Additionally these settlements are in many cases informal and thus vulnerable to such hazards, resulting in significant risk. Such watersheds are often quiet small, and generally there is little or no information from gauges to help characterise risk. To help identify watersheds in which flood management measures are to be targeted, a rapid assessment of risk is required. In this paper a novel approach is presented where indicators of susceptibility and vulnerability to flash floods were used to prioritize 106 mountain watersheds in Bogotá (Colombia). Variables recognized in literature to determine the dominant processes both in susceptibility and vulnerability to flash floods were used to construct the indicators. Susceptibility was considered to increase with flashiness and the possibility of debris flow events occurring. This was assessed through the use of an indicator composed of a morphometric indicator and a land use indicator. The former was constructed using morphological variables recognized in literature to significantly influence flashiness and occurrence of debris flows; the latter was constructed in terms of percentage of vegetation cover, urban area and bare soil. The morphometric indicator was compared with the results of a debris flow propagation algorithm to assess its capacity in indentifying the morphological conditions of a watershed that make it able to transport debris flows. Propagation was carried out through the use of the Modified Single Flow Direction algorithm, following previous identification of source areas by applying thresholds identified in the area-slope curve of the watersheds and empirical thresholds. Results show that the morphometric variables can be grouped in four categories: size, shape, hypsometry and energy, with the energy the component found to best explain the

  8. Natural flood retention in mountain areas by forests and forest like short rotation coppices

    Science.gov (United States)

    Reinhardt-Imjela, Christian; Schulte, Achim; Hartwich, Jens

    2017-04-01

    Natural water retention is an important element of flood risk management in flood generating headwater areas in the low mountain ranges of Central Europe. In this context forests are of particular interest because of the high infiltration capacities of the soils and to increase water retention reforestation of agricultural land would be worthwhile. However competing claims for land use in intensely cultivated regions in Central Europe impede reforestation plans so the potential for a significant increase of natural water retention in forests is strongly limited. Nevertheless the development of innovative forms of land use and crop types opens new perspectives for a combination of agricultural land use with the water retention potential of forests. Recently the increasing demand for renewable energy resources leads to the cultivation of fast growing poplar and willow hybrids on agricultural land in short rotation coppices (SRC). Harvested in cycles of three to six years the wood from the plantations can be used as wood chips for heat and electricity production in specialized power plants. With short rotation plantations a crop type is established on arable land which is similar to forests so that an improvement of water retention can be expected. To what extend SRC may contribute to flood attenuation in headwater areas is investigated for the Chemnitzbach watershed (48 km2) in the Eastern Ore Mountains (Free State of Saxony, Germany), a low mountain range which is an important source of flood runoff in the Elbe basin. The study is based on a rainfall-runoff model of flood events using the conceptual modelling system NASIM. First results reveal a significant reduction of the flood peaks after the implementation of short rotation coppices. However the effect strongly depends on two factors. The first factor is the availability of areas for the plantations. For a substantial impact on the watershed scale large areas are required and with decreasing percentages of SRC

  9. Methodological Framework for Analysing Cascading Effects from Flood Events: The Case of Sukhumvit Area, Bangkok, Thailand

    Directory of Open Access Journals (Sweden)

    Geofrey Hilly

    2018-01-01

    Full Text Available Impacts from floods in urban areas can be diverse and wide ranging. These can include the loss of human life, infrastructure and property damages, as well as other kinds of nuisance and inconvenience to urban life. Hence, the ability to identify and quantify wider ranging effects from floods is of the utmost importance to urban flood managers and infrastructure operators. The present work provides a contribution in this direction and describes a methodological framework for analysing cascading effects from floods that has been applied for the Sukhumvit area in Bangkok (Thailand. It demonstrates that the effects from floods can be much broader in their reach and magnitude than the sole impacts incurred from direct and immediate losses. In Sukhumvit, these include loss of critical services, assets and goods, traffic congestion and delays in transportation, loss of business and income, disturbances and discomfort to the residents, and all these can be traced with the careful analysis of cascading effects. The present work explored the use of different visualization options to present the findings. These include a casual loop diagram, a HAZUR resilience map, a tree diagram and GIS maps.

  10. Thunderstorms and flooding of August 17, 2007, with a context provided by a history of other large storm and flood events in the Black Hills area of South Dakota

    Science.gov (United States)

    Driscoll, Daniel G.; Bunkers, Matthew J.; Carter, Janet M.; Stamm, John F.; Williamson, Joyce E.

    2010-01-01

    The Black Hills area of western South Dakota has a history of damaging flash floods that have resulted primarily from exceptionally strong rain-producing thunderstorms. The best known example is the catastrophic storm system of June 9-10, 1972, which caused severe flooding in several major drainages near Rapid City and resulted in 238 deaths. More recently, severe thunderstorms caused flash flooding near Piedmont and Hermosa on August 17, 2007. Obtaining a thorough understanding of peak-flow characteristics for low-probability floods will require a comprehensive long-term approach involving (1) documentation of scientific information for extreme events such as these; (2) long-term collection of systematic peak-flow records; and (3) regional assessments of a wide variety of peak-flow information. To that end, the U.S. Geological Survey cooperated with the South Dakota Department of Transportation and National Weather Service to produce this report, which provides documentation regarding the August 17, 2007, storm and associated flooding and provides a context through examination of other large storm and flood events in the Black Hills area. The area affected by the August 17, 2007, storms and associated flooding generally was within the area affected by the larger storm of June 9-10, 1972. The maximum observed 2007 precipitation totals of between 10.00 and 10.50 inches occurred within about 2-3 hours in a small area about 5 miles west of Hermosa. The maximum documented precipitation amount in 1972 was 15.0 inches, and precipitation totals of 10.0 inches or more were documented for 34 locations within an area of about 76 square miles. A peak flow of less than 1 cubic foot per second occurred upstream from the 2007 storm extent for streamflow-gaging station 06404000 (Battle Creek near Keystone); whereas, the 1972 peak flow of 26,200 cubic feet per second was large, relative to the drainage area of only 58.6 square miles. Farther downstream along Battle Creek, a 2007

  11. 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

    Flood risk changes in Mediterranean Region integrate multiple factors, some of them related with the hazard (i.e. rainfall intensity), the vulnerability and exposure (i.e. population or assets), feedback processes that affect both hazard and vulnerability (i.e. urbanization of flood prone areas), mitigation and adaptation measures (i.e. rainwater tanks or early warning systems), and the available information used to estimate flood events (i.e. newspapers or gauged data). Flood events in the West Mediterranean region are usually produced as a consequence of very intense and local precipitation, mainly recorded on late summer and autumn that can give place to flash-floods in little torrential rivers (usually non-permanent flows) or urban floods. The Metropolitan Area of Barcelona (AMB), Spain, constitutes a good paradigm of a Mediterranean coast region, with strong urbanization of flood prone areas and high population density in an area crossed by numerous streams. The AMB is constituted by 36 municipalities with a total population above 3.200.000 inhabitants in an extension of 636 km². The major part of the population is concentrated between the Besós River and the Llobregat River, the Littoral Range and the Mediterranean Sea. Although both rivers have experienced catastrophic flood events (i.e. 25 September 1962, 815 deaths; 19-23 September 1971, 19 deaths; October 1987, 8 deaths), the most frequent situation is related with floods in non-permanent streams. Their main impacts are consequence of drainage and runoff problems and can affect both urban and rural areas. This contribution explores the evolution of land uses, population and precipitation from the middle of the 20th century until now, and how these changes have affected (or not), the flood risk. To do it, daily and sub-daily rainfall series, discharge series for the Llobregat and Besós Rivers, population data and land use changes have been analyzed. Future precipitation projections provided by an

  12. A new approach for river flood extent delineation in rural and urban areas combining RADARSAT-2 imagery and flood recurrence interval data

    Science.gov (United States)

    Tanguy, Marion; Bernier, Monique; Chokmani, Karem

    2015-04-01

    When a flood hits an inhabited area, managers and services responsible for public safety need precise, reliable and up to date maps of the areas affected by the flood, in order to quickly roll out and to coordinate the adequate intervention and assistance plans required to limit the human and material damages caused by the disaster. Synthetic aperture radar (SAR) sensors are now considered as one of the most adapted tool for flood detection and mapping in a context of crisis management. Indeed, due to their capacity to acquire data night and day, in almost all meteorological conditions, SAR sensors allow the acquisition of synoptic but detailed views of the areas affected by the flood, even during the active phases of the event. Moreover, new generation sensors such as RADARSAT-2, TerraSAR-X, COSMO-SkyMed, are providing very high resolution images of the disaster (down to 1m ground resolution). Further, critical improvements have been made on the temporal repetitivity of acquisitions and on data availability, through the development of satellite constellations (i.e the four COSMO-Skymed or the Sentinel-1A and 1B satellites) and thanks to the implementation of the International Charter "Space and Major Disasters", which guarantees high priority images acquisition and delivery with 4 to 12 hours. If detection of open water flooded areas is relatively straightforward with SAR imagery, flood detection in built-up areas is often associated with important issues. Indeed, because of the side looking geometry of the SAR sensors, structures such as tall vegetation and structures parallel to the satellite direction of travel may produce shadow and layover effects, leading to important over and under-detections of flooded pixels. Besides, the numerous permanent water-surfaces like radar response areas present in built-up environments, such as parking lots, roads etc., may be mixed up with flooded areas, resulting in substantial inaccuracies in the final flood map. In spite of

  13. The determination of risk areas for muddy floods based on a worst-case erosion modelling

    Science.gov (United States)

    Saathoff, Ulfert; Schindewolf, Marcus; Annika Arévalo, Sarah

    2013-04-01

    Soil erosion and muddy floods are a frequently occurring hazard in the German state of Saxony, because of the topography and the high relief energy together with the high proportion of arable land. Still, the events are rather heterogeneously distributed and we do not know where damage is likely to occur. The goal of this study is to locate hot spots for the risk of muddy floods, with the objective to prevent high economic damage in future. We applied a soil erosion and deposition map of Saxony, calculated with the process based soil erosion model EROSION 3D. This map shows the potential soil erosion and transported sediment for worst case soil conditions and a 10 year rain storm event. Furthermore, a map of the current landuse in the state is used. From the landuse map, we extracted those areas that are especially vulnerable to muddy floods, like residential and industrial areas, infrastructural facilities (e.g. power plants, hospitals) and highways. In combination with the output of the soil erosion model, the amount of sediment, that enters each single landuse entity, is calculated. Based on this data, a state-wide map with classified risks is created. The results are furthermore used to identify the risk of muddy floods for each single municipality in Saxony. The results are evaluated with data of real occurred muddy flood events with documented locations during the period between 2000 and 2010. Additionally, plausibility tests are performed for selected areas (examination of landuse, topography and soil). The results prove to be plausible and most of the documented events can be explained by the modelled risk map. The created map can be used by different institutions like city and traffic planners, to estimate the risk of muddy flood occurrence at specific locations. Furthermore, the risk map can serve insurance companies to evaluate the insurance risk of a building. To make them easily accessible, the risk map will be published online via a web GIS

  14. Flash Flood Hazard Susceptibility Mapping Using Frequency Ratio and Statistical Index Methods in Coalmine Subsidence Areas

    Directory of Open Access Journals (Sweden)

    Chen Cao

    2016-09-01

    Full Text Available This study focused on producing flash flood hazard susceptibility maps (FFHSM using frequency ratio (FR and statistical index (SI models in the Xiqu Gully (XQG of Beijing, China. First, a total of 85 flash flood hazard locations (n = 85 were surveyed in the field and plotted using geographic information system (GIS software. Based on the flash flood hazard locations, a flood hazard inventory map was built. Seventy percent (n = 60 of the flooding hazard locations were randomly selected for building the models. The remaining 30% (n = 25 of the flooded hazard locations were used for validation. Considering that the XQG used to be a coal mining area, coalmine caves and subsidence caused by coal mining exist in this catchment, as well as many ground fissures. Thus, this study took the subsidence risk level into consideration for FFHSM. The ten conditioning parameters were elevation, slope, curvature, land use, geology, soil texture, subsidence risk area, stream power index (SPI, topographic wetness index (TWI, and short-term heavy rain. This study also tested different classification schemes for the values for each conditional parameter and checked their impacts on the results. The accuracy of the FFHSM was validated using area under the curve (AUC analysis. Classification accuracies were 86.61%, 83.35%, and 78.52% using frequency ratio (FR-natural breaks, statistical index (SI-natural breaks and FR-manual classification schemes, respectively. Associated prediction accuracies were 83.69%, 81.22%, and 74.23%, respectively. It was found that FR modeling using a natural breaks classification method was more appropriate for generating FFHSM for the Xiqu Gully.

  15. Variations in flood magnitude-effect relations and the implications for flood risk assessment and river management

    Science.gov (United States)

    Hooke, J. M.

    2015-12-01

    In spite of major physical impacts from large floods, present river management rarely takes into account the possible dynamics and variation in magnitude-impact relations over time in flood risk mapping and assessment nor incorporates feedback effects of changes into modelling. Using examples from the literature and from field measurements over several decades in two contrasting environments, a semi-arid region and a humid-temperate region, temporal variations in channel response to flood events are evaluated. The evidence demonstrates how flood physical impacts can vary at a location over time. The factors influencing that variation on differing timescales are examined. The analysis indicates the importance of morphological changes and trajectory of adjustment in relation to thresholds, and that trends in force or resistance can take place over various timescales, altering those thresholds. Sediment supply can also change with altered connectivity upstream and changes in state of hillslope-channel coupling. It demonstrates that seasonal timing and sequence of events can affect response, particularly deposition through sediment supply. Duration can also have a significant effect and modify the magnitude relation. Lack of response or deposits in some events can mean that flood frequency using such evidence is underestimated. A framework for assessment of both past and possible future changes is provided which emphasises the uncertainty and the inconstancy of the magnitude-impact relation and highlights the dynamic factors and nature of variability that should be considered in sustainable management of river channels.

  16. Towards large scale stochastic rainfall models for flood risk assessment in trans-national basins

    Science.gov (United States)

    Serinaldi, F.; Kilsby, C. G.

    2012-04-01

    While extensive research has been devoted to rainfall-runoff modelling for risk assessment in small and medium size watersheds, less attention has been paid, so far, to large scale trans-national basins, where flood events have severe societal and economic impacts with magnitudes quantified in billions of Euros. As an example, in the April 2006 flood events along the Danube basin at least 10 people lost their lives and up to 30 000 people were displaced, with overall damages estimated at more than half a billion Euros. In this context, refined analytical methods are fundamental to improve the risk assessment and, then, the design of structural and non structural measures of protection, such as hydraulic works and insurance/reinsurance policies. Since flood events are mainly driven by exceptional rainfall events, suitable characterization and modelling of space-time properties of rainfall fields is a key issue to perform a reliable flood risk analysis based on alternative precipitation scenarios to be fed in a new generation of large scale rainfall-runoff models. Ultimately, this approach should be extended to a global flood risk model. However, as the need of rainfall models able to account for and simulate spatio-temporal properties of rainfall fields over large areas is rather new, the development of new rainfall simulation frameworks is a challenging task involving that faces with the problem of overcoming the drawbacks of the existing modelling schemes (devised for smaller spatial scales), but keeping the desirable properties. In this study, we critically summarize the most widely used approaches for rainfall simulation. Focusing on stochastic approaches, we stress the importance of introducing suitable climate forcings in these simulation schemes in order to account for the physical coherence of rainfall fields over wide areas. Based on preliminary considerations, we suggest a modelling framework relying on the Generalized Additive Models for Location, Scale

  17. Comparison of Flood Vulnerability Assessments to Climate Change by Construction Frameworks for a Composite Indicator

    Directory of Open Access Journals (Sweden)

    Jong Seok Lee

    2018-03-01

    Full Text Available As extreme weather conditions due to climate change can cause deadly flood damages all around the world, a role of the flood vulnerability assessment has become recognized as one of the preemptive measures in nonstructural flood mitigation strategies. Although the flood vulnerability is most commonly assessed by a composite indicator compiled from multidimensional phenomena and multiple conflicting criteria associated with floods, directly or indirectly, it has been often overlooked that the construction frameworks and processes can have a significant influence on the flood vulnerability indicator outcomes. This study has, therefore, compared the flood vulnerability ranking orders for the 54 administrative districts in the Nakdong River Watershed of the Korean Peninsula, ranked from composite indicators by different frameworks and multi-attribute utility functions for combining the three assessment components, such as exposure, sensitivity, and coping, presented in the IPCC Third Assessment Report. The results show that the different aggregation components and utility functions under the same proxy variable system can lead to larger volatility of flood vulnerability rankings than expected. It is concluded that the vulnerability indicator needs to be derived from all three assessment components by a multiplicative utility function for a desirable flood vulnerability assessment to climate change.

  18. 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.

  19. Assessment of Tangible Direct Flood Damage Using a Spatial Analysis Approach under the Effects of Climate Change: Case Study in an Urban Watershed in Hanoi, Vietnam

    Directory of Open Access Journals (Sweden)

    Mohamed Kefi

    2018-01-01

    Full Text Available Due to climate change, the frequency and intensity of Hydro-Meteorological disasters, such as floods, are increasing. Therefore, the main purpose of this work is to assess tangible future flood damage in the urban watershed of the To Lich River in Hanoi, Vietnam. An approach based on spatial analysis, which requires the integration of several types of data related to flood characteristics that include depth, in particular, land-use classes, property values, and damage rates, is applied for the analysis. To simulate the future scenarios of flooding, the effects of climate change and land-use changes are estimated for 2030. Additionally, two scenarios based on the implementation of flood control measures are analyzed to demonstrate the effect of adaptation strategies. The findings show that climate change combined with the expansion of built-up areas increases the vulnerability of urban areas to flooding and economic damage. The results also reveal that the impacts of climate change will increase the total damage from floods by 26%. However, appropriate flood mitigation will be helpful in reducing the impacts of losses from floods by approximately 8% with the restoration of lakes and by approximately 29% with the implementation of water-sensitive urban design (WSUD. This study will be useful in helping to identify and map flood-prone areas at local and regional scales, which can lead to the detection and prioritization of exposed areas for appropriate countermeasures in a timely manner. In addition, the quantification of flood damage can be an important indicator to enhance the awareness of local decision-makers on improving the efficiency of regional flood risk reduction strategies.

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

    Directory of Open Access Journals (Sweden)

    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.

  1. Predicted high-water elevations for selected flood events at the Albert Pike Recreation Area, Ouachita National Forest

    Science.gov (United States)

    D.A. Marion

    2012-01-01

    The hydraulic characteristics are determined for the June 11, 2010, flood on the Little Missouri River at the Albert Pike Recreation Area in Arkansas. These characteristics are then used to predict the high-water elevations for the 10-, 25-, 50-, and 100-year flood events in the Loop B, C, and D Campgrounds of the recreation area. The peak discharge and related...

  2. Assessment of flood potential for eight buildings at the Y-12 Plant

    International Nuclear Information System (INIS)

    Eiffe, M.A.

    1997-01-01

    In 1995, P-SQUARED Technologies, Inc., (P2T) was tasked with defining the flood potential for seven buildings at the Y-12 Plant (Buildings 9204-2, 9204-2E, 9206, 9212, 9215, 9720-5, and 9995) in the assumed event of a design storm with a recurrence interval of 10,000 years. At the conclusion of the study, P2T prepared and submitted a report summarizing the flood potential for those seven buildings. In November of 1997, P2T was tasked with (1) defining flood potential for the same seven buildings listed above for design storms with recurrence intervals of 500 years and 2000 years, and (2) defining flood potential for Building 9720-38 for design storms with recurrence intervals of 500 years, 2000 years, and 10,000 years. This report presents the results of the analyses conducted to define flood potential at these locations and for these recurrence intervals. None of the buildings investigated are completely safe from flooding during the storms considered. Runoff from rooftops may cause limited flooding in any areas where water is allowed to pond next to doors, vents, windows, or other openings. Flooding depths inside buildings in these areas should be limited to 1 ft or less. Buildings with openings below the grade of adjacent roads are also subject to flooding, with flood levels dependent upon the topography in that location

  3. A Multimethod Approach towards Assessing Urban Flood Patterns and Its Associated Vulnerabilities in Singapore

    Directory of Open Access Journals (Sweden)

    Winston T. L. Chow

    2016-01-01

    Full Text Available We investigated flooding patterns in the urbanised city-state of Singapore through a multimethod approach combining station precipitation data with archival newspaper and governmental records; changes in flash floods frequencies or reported impacts of floods towards Singapore society were documented. We subsequently discussed potential flooding impacts in the context of urban vulnerability, based on future urbanisation and forecasted precipitation projections for Singapore. We find that, despite effective flood management, (i significant increases in reported flash flood frequency occurred in contemporary (post-2000 relative to preceding (1984–1999 periods, (ii these flash floods coincide with more localised, “patchy” storm events, (iii storms in recent years are also more intense and frequent, and (iv floods result in low human casualties but have high economic costs via insurance damage claims. We assess that Singapore presently has low vulnerability to floods vis-à-vis other regional cities largely due to holistic flood management via consistent and successful infrastructural development, widespread flood monitoring, and effective advisory platforms. We conclude, however, that future vulnerabilities may increase from stresses arising from physical exposure to climate change and from demographic sensitivity via rapid population growth. Anticipating these changes is potentially useful in maintaining the high resilience of Singapore towards this hydrometeorological hazard.

  4. Integrating heterogeneous earth observation data for assessment of high-resolution inundation boundaries generated during flood emergencies.

    Science.gov (United States)

    Sava, E.; Cervone, G.; Kalyanapu, A. J.; Sampson, K. M.

    2017-12-01

    The increasing trend in flooding events, paired with rapid urbanization and an aging infrastructure is projected to enhance the risk of catastrophic losses and increase the frequency of both flash and large area floods. During such events, it is critical for decision makers and emergency responders to have access to timely actionable knowledge regarding preparedness, emergency response, and recovery before, during and after a disaster. Large volumes of data sets derived from sophisticated sensors, mobile phones, and social media feeds are increasingly being used to improve citizen services and provide clues to the best way to respond to emergencies through the use of visualization and GIS mapping. Such data, coupled with recent advancements in data fusion techniques of remote sensing with near real time heterogeneous datasets have allowed decision makers to more efficiently extract precise and relevant knowledge and better understand how damage caused by disasters have real time effects on urban population. This research assesses the feasibility of integrating multiple sources of contributed data into hydrodynamic models for flood inundation simulation and estimating damage assessment. It integrates multiple sources of high-resolution physiographic data such as satellite remote sensing imagery coupled with non-authoritative data such as Civil Air Patrol (CAP) and `during-event' social media observations of flood inundation in order to improve the identification of flood mapping. The goal is to augment remote sensing imagery with new open-source datasets to generate flood extend maps at higher temporal and spatial resolution. The proposed methodology is applied on two test cases, relative to the 2013 Boulder Colorado flood and the 2015 floods in Texas.

  5. 78 FR 75370 - Draft Supplemental Environmental Assessment and Finding of No Significant Impact for Flood...

    Science.gov (United States)

    2013-12-11

    ... Environmental Assessment and Finding of No Significant Impact for Flood Control Improvements to the Rio Grande... Supplemental Environmental Assessment (SEA) and Finding of No Significant Impact (FONSI). SUMMARY: Pursuant to... Significant Impact for Flood Control Improvements to the Rio Grande Canalization Project in Vado, New Mexico...

  6. Systematic testing of flood adaptation options in urban areas through simulations

    Science.gov (United States)

    Löwe, Roland; Urich, Christian; Sto. Domingo, Nina; Mark, Ole; Deletic, Ana; Arnbjerg-Nielsen, Karsten

    2016-04-01

    While models can quantify flood risk in great detail, the results are subject to a number of deep uncertainties. Climate dependent drivers such as sea level and rainfall intensities, population growth and economic development all have a strong influence on future flood risk, but future developments can only be estimated coarsely. In such a situation, robust decision making frameworks call for the systematic evaluation of mitigation measures against ensembles of potential futures. We have coupled the urban development software DAnCE4Water and the 1D-2D hydraulic simulation package MIKE FLOOD to create a framework that allows for such systematic evaluations, considering mitigation measures under a variety of climate futures and urban development scenarios. A wide spectrum of mitigation measures can be considered in this setup, ranging from structural measures such as modifications of the sewer network over local retention of rainwater and the modification of surface flow paths to policy measures such as restrictions on urban development in flood prone areas or master plans that encourage compact development. The setup was tested in a 300 ha residential catchment in Melbourne, Australia. The results clearly demonstrate the importance of considering a range of potential futures in the planning process. For example, local rainwater retention measures strongly reduce flood risk a scenario with moderate increase of rain intensities and moderate urban growth, but their performance strongly varies, yielding very little improvement in situations with pronounced climate change. The systematic testing of adaptation measures further allows for the identification of so-called adaptation tipping points, i.e. levels for the drivers of flood risk where the desired level of flood risk is exceeded despite the implementation of (a combination of) mitigation measures. Assuming a range of development rates for the drivers of flood risk, such tipping points can be translated into

  7. Flood Hazard Recurrence Frequencies for A-, K- and L-Areas, and Revised Frequencies for C-, F-, E-, S-, H-, Y- and Z-Areas

    International Nuclear Information System (INIS)

    Chen, K.F.

    2000-01-01

    Department of Energy (DOE) Order 420.1, Facility Safety, outlines the requirements for Natural Phenomena Hazard (NPH) mitigation for new and existing DOE facilities. The NPH considered in this report is flooding. The facility-specific probabilistic flood hazard curve defines as a function of water elevation the annual probability of occurrence or the return period in years. Based on facility-specific probabilistic flood hazard curves and the nature of facility operations (e.g., involving hazardous or radioactive materials), facility managers can design permanent or temporary devices to prevent the propagation of flood on site, and develop emergency preparedness plans to mitigate the consequences of floods. Methods were developed to determine the probabilistic flood elevation curves for Savannah River Site (SRS) facilities. This report presents the methods used to determine the probabilistic flood elevation curves for A-, K-, C-, F-, E-, H-, S-, Y-, Z- and L-Areas

  8. Analysis the Accuracy of Digital Elevation Model (DEM) for Flood Modelling on Lowland Area

    Science.gov (United States)

    Zainol Abidin, Ku Hasna Zainurin Ku; Razi, Mohd Adib Mohammad; Bukari, Saifullizan Mohd

    2018-04-01

    Flood is one type of natural disaster that occurs almost every year in Malaysia. Commonly the lowland areas are the worst affected areas. This kind of disaster is controllable by using an accurate data for proposing any kinds of solutions. Elevation data is one of the data used to produce solutions for flooding. Currently, the research about the application of Digital Elevation Model (DEM) in hydrology was increased where this kind of model will identify the elevation for required areas. University of Tun Hussein Onn Malaysia is one of the lowland areas which facing flood problems on 2006. Therefore, this area was chosen in order to produce DEM which focussed on University Health Centre (PKU) and drainage area around Civil and Environment Faculty (FKAAS). Unmanned Aerial Vehicle used to collect aerial photos data then undergoes a process of generating DEM according to three types of accuracy and quality from Agisoft PhotoScan software. The higher the level of accuracy and quality of DEM produced, the longer time taken to generate a DEM. The reading of the errors created while producing the DEM shows almost 0.01 different. Therefore, it has been identified there are some important parameters which influenced the accuracy of DEM.

  9. Large-scale assessment of flood risk and the effects of mitigation measures along the Elbe River

    NARCIS (Netherlands)

    de Kok, Jean-Luc; Grossmann, M.

    2010-01-01

    The downstream effects of flood risk mitigation measures and the necessity to develop flood risk management strategies that are effective on a basin scale call for a flood risk assessment methodology that can be applied at the scale of a large river. We present an example of a rapid flood risk

  10. The climate and flood risk potential of northern areas of Pakistan

    International Nuclear Information System (INIS)

    Awan, S.A.

    2002-01-01

    The extreme floods in northern parts of Pakistan are caused by glacier lake outbursts and Dam-Breaks following landslides, which block river valleys. Geographically glacier dams in mountain rivers and valleys have occurred from the east-western and west-western Karakuram ranges and in the lesser Karakuram range floods which arise from Karakuram precipitation and temperature of various region pose greater problem, as these floods are neither homogeneous nor stationary. These floods arise from various generating mechanisms i. e. generated by melting of snow and glacier and those generated from the monsoon rainfall and dam-breaks following landslide into the river and out burst of glacier lake. The estimation of present and future risk of flooding at sites in northern Pakistan requires an understanding, of the climate, which provides, the generating mechanism of floods. Climates are extremely variable and depend op broad global circulation patterns and local topographic influences. The variables of the climate are studied using available data, with emphasis on temperature and precipitation Spatial Co-relation in northern area stations have been conducted to find Co-relation Co-efficient, using regression analysis. This is spread over intra seasonal and inter station comparison. The time series analysis of the climatic variables has been conducted to examine geographically and statistically the trend in their behaviour. This may be reflected in the hydrological regime of glaciers and rivers and it can cause non linear flood series through changes in any one of the flood generating mechanism. The climate feed-back mechanism has been discussed, which are practically important because they assist seasonal prediction of climate and flow in the Indus. Additionally if climate warming is causing an upward Trend in winter and spring temperature and reduction in snowfall, the effect might be felt more widely over the region. The non-linear changes with elevation and differences

  11. A metric-based assessment of flood risk and vulnerability of rural communities in the Lower Shire Valley, Malawi

    Science.gov (United States)

    Adeloye, A. J.; Mwale, F. D.; Dulanya, Z.

    2015-06-01

    In response to the increasing frequency and economic damages of natural disasters globally, disaster risk management has evolved to incorporate risk assessments that are multi-dimensional, integrated and metric-based. This is to support knowledge-based decision making and hence sustainable risk reduction. In Malawi and most of Sub-Saharan Africa (SSA), however, flood risk studies remain focussed on understanding causation, impacts, perceptions and coping and adaptation measures. Using the IPCC Framework, this study has quantified and profiled risk to flooding of rural, subsistent communities in the Lower Shire Valley, Malawi. Flood risk was obtained by integrating hazard and vulnerability. Flood hazard was characterised in terms of flood depth and inundation area obtained through hydraulic modelling in the valley with Lisflood-FP, while the vulnerability was indexed through analysis of exposure, susceptibility and capacity that were linked to social, economic, environmental and physical perspectives. Data on these were collected through structured interviews of the communities. The implementation of the entire analysis within GIS enabled the visualisation of spatial variability in flood risk in the valley. The results show predominantly medium levels in hazardousness, vulnerability and risk. The vulnerability is dominated by a high to very high susceptibility. Economic and physical capacities tend to be predominantly low but social capacity is significantly high, resulting in overall medium levels of capacity-induced vulnerability. Exposure manifests as medium. The vulnerability and risk showed marginal spatial variability. The paper concludes with recommendations on how these outcomes could inform policy interventions in the Valley.

  12. Integrating Physical and Topographic Information Into a Fuzzy Scheme to Map Flooded Area by SAR

    Directory of Open Access Journals (Sweden)

    Flavia Macina

    2008-07-01

    Full Text Available A flood mapping procedure based on a fuzzy sets theory has been developed. The method is based on the integration of Synthetic Aperture Radar (SAR measurements with additional data on the inundated area, such as a land cover map and a digital elevation model (DEM. The information on land cover has allowed us to account for both specular reflection, typical of open water, and double bounce backscattering, typical of forested and urban areas. DEM has been exploited to include simple hydraulic considerations on the dependence of inundation probability on surface characteristics. Contextual information has been taken into account too. The proposed algorithm has been tested on a flood occurred in Italy on November 1994. A pair of ERS-1 images, collected before and after (three days later the flood, has been used. The results have been compared with the data provided by a ground survey carried out when the flood reached its maximum extension. Despite the temporal mismatch between the survey and the post-inundation SAR image, the comparison has yielded encouraging results, with the 87% of the pixels correctly classified as inundated.

  13. Integrating Physical and Topographic Information Into a Fuzzy Scheme to Map Flooded Area by SAR.

    Science.gov (United States)

    Pierdicca, Nazzareno; Chini, Marco; Pulvirenti, Luca; Macina, Flavia

    2008-07-10

    A flood mapping procedure based on a fuzzy sets theory has been developed. The method is based on the integration of Synthetic Aperture Radar (SAR) measurements with additional data on the inundated area, such as a land cover map and a digital elevation model (DEM). The information on land cover has allowed us to account for both specular reflection, typical of open water, and double bounce backscattering, typical of forested and urban areas. DEM has been exploited to include simple hydraulic considerations on the dependence of inundation probability on surface characteristics. Contextual information has been taken into account too. The proposed algorithm has been tested on a flood occurred in Italy on November 1994. A pair of ERS-1 images, collected before and after (three days later) the flood, has been used. The results have been compared with the data provided by a ground survey carried out when the flood reached its maximum extension. Despite the temporal mismatch between the survey and the post-inundation SAR image, the comparison has yielded encouraging results, with the 87% of the pixels correctly classified as inundated.

  14. Integrating hydrodynamic models and COSMO-SkyMed derived products for flood damage assessment

    Science.gov (United States)

    Giuffra, Flavio; Boni, Giorgio; Pulvirenti, Luca; Pierdicca, Nazzareno; Rudari, Roberto; Fiorini, Mattia

    2015-04-01

    Floods are the most frequent weather disasters in the world and probably the most costly in terms of social and economic losses. They may have a strong impact on infrastructures and health because the range of possible damages includes casualties, loss of housing and destruction of crops. Presently, the most common approach for remotely sensing floods is the use of synthetic aperture radar (SAR) images. Key features of SAR data for inundation mapping are the synoptic view, the capability to operate even in cloudy conditions and during both day and night time and the sensitivity of the microwave radiation to water. The launch of a new generation of instruments, such as TerraSAR-X and COSMO-SkyMed (CSK) allows producing near real time flood maps having a spatial resolution in the order of 1-5 m. Moreover, the present (CSK) and upcoming (Sentinel-1) constellations permit the acquisition of radar data characterized by a short revisit time (in the order of some hours for CSK), so that the production of frequent inundation maps can be envisaged. Nonetheless, gaps might be present in the SAR-derived flood maps because of the limited area imaged by SAR; moreover, the detection of floodwater may be complicated by the presence of very dense vegetation or urban settlements. Hence the need to complement SAR-derived flood maps with the outputs of physical models. Physical models allow delivering to end users very useful information for a complete flood damage assessment, such as data on water depths and flow directions, which cannot be directly derived from satellite remote sensing images. In addition, the flood extent predictions of hydraulic models can be compared to SAR-derived inundation maps to calibrate the models, or to fill the aforementioned gaps that can be present in the SAR-derived maps. Finally, physical models enable the construction of risk scenarios useful for emergency managers to take their decisions and for programming additional SAR acquisitions in order to

  15. Tsunami hazard assessment in El Salvador, Central America, from seismic sources through flooding numerical models.

    Science.gov (United States)

    Álvarez-Gómez, J. A.; Aniel-Quiroga, Í.; Gutiérrez-Gutiérrez, O. Q.; Larreynaga, J.; González, M.; Castro, M.; Gavidia, F.; Aguirre-Ayerbe, I.; González-Riancho, P.; Carreño, E.

    2013-11-01

    El Salvador is the smallest and most densely populated country in Central America; its coast has an approximate length of 320 km, 29 municipalities and more than 700 000 inhabitants. In El Salvador there were 15 recorded tsunamis between 1859 and 2012, 3 of them causing damages and resulting in hundreds of victims. Hazard assessment is commonly based on propagation numerical models for earthquake-generated tsunamis and can be approached through both probabilistic and deterministic methods. A deterministic approximation has been applied in this study as it provides essential information for coastal planning and management. The objective of the research was twofold: on the one hand the characterization of the threat over the entire coast of El Salvador, and on the other the computation of flooding maps for the three main localities of the Salvadorian coast. For the latter we developed high-resolution flooding models. For the former, due to the extension of the coastal area, we computed maximum elevation maps, and from the elevation in the near shore we computed an estimation of the run-up and the flooded area using empirical relations. We have considered local sources located in the Middle America Trench, characterized seismotectonically, and distant sources in the rest of Pacific Basin, using historical and recent earthquakes and tsunamis. We used a hybrid finite differences-finite volumes numerical model in this work, based on the linear and non-linear shallow water equations, to simulate a total of 24 earthquake-generated tsunami scenarios. Our results show that at the western Salvadorian coast, run-up values higher than 5 m are common, while in the eastern area, approximately from La Libertad to the Gulf of Fonseca, the run-up values are lower. The more exposed areas to flooding are the lowlands in the Lempa River delta and the Barra de Santiago Western Plains. The results of the empirical approximation used for the whole country are similar to the results

  16. Natural radioactivity levels in soil samples around the flood affected salt field area, Kelambakkam, Chennai, Tamilnadu, India using gamma ray spectrometry

    International Nuclear Information System (INIS)

    Rajalakshmi, A.; Chandrasekaran, A.; Thangam, V.; Jananee, B.

    2018-01-01

    Humans are exposed to natural radiation from external sources, which include radionuclides in the earth and cosmic radiation. Gamma Ray spectroscopic technique was used to assess the natural radioactivity in soils around the flood affected salt field area, Kelambakkam Chennai, Tamilnadu, India. The activity concentration of 238 U, 232 Th, 40 K and absorbed dose rate of soil samples were calculated to assess the radiation hazards in the study area

  17. Potentialities of ensemble strategies for flood forecasting over the Milano urban area

    Science.gov (United States)

    Ravazzani, Giovanni; Amengual, Arnau; Ceppi, Alessandro; Homar, Víctor; Romero, Romu; Lombardi, Gabriele; Mancini, Marco

    2016-08-01

    Analysis of ensemble forecasting strategies, which can provide a tangible backing for flood early warning procedures and mitigation measures over the Mediterranean region, is one of the fundamental motivations of the international HyMeX programme. Here, we examine two severe hydrometeorological episodes that affected the Milano urban area and for which the complex flood protection system of the city did not completely succeed. Indeed, flood damage have exponentially increased during the last 60 years, due to industrial and urban developments. Thus, the improvement of the Milano flood control system needs a synergism between structural and non-structural approaches. First, we examine how land-use changes due to urban development have altered the hydrological response to intense rainfalls. Second, we test a flood forecasting system which comprises the Flash-flood Event-based Spatially distributed rainfall-runoff Transformation, including Water Balance (FEST-WB) and the Weather Research and Forecasting (WRF) models. Accurate forecasts of deep moist convection and extreme precipitation are difficult to be predicted due to uncertainties arising from the numeric weather prediction (NWP) physical parameterizations and high sensitivity to misrepresentation of the atmospheric state; however, two hydrological ensemble prediction systems (HEPS) have been designed to explicitly cope with uncertainties in the initial and lateral boundary conditions (IC/LBCs) and physical parameterizations of the NWP model. No substantial differences in skill have been found between both ensemble strategies when considering an enhanced diversity of IC/LBCs for the perturbed initial conditions ensemble. Furthermore, no additional benefits have been found by considering more frequent LBCs in a mixed physics ensemble, as ensemble spread seems to be reduced. These findings could help to design the most appropriate ensemble strategies before these hydrometeorological extremes, given the computational

  18. Assemblage of drosophilids (Diptera, Drosophilidae inhabiting flooded and nonflooded areas in the extreme South of Brazil

    Directory of Open Access Journals (Sweden)

    L.B. Duarte

    Full Text Available ABSTRACT Several studies on the potential use of drosophilid assemblages as bioindicator systems have been carried out in the last years. Nevertheless, the successful application of these organisms in these systems requires adequate filling of several knowledge gaps. In this sense, little is known about drosophilid assemblages in wetlands and flooded areas. The present study provides the first survey of drosophilid species inhabiting such environments in the extreme South of Brazil and compares general beta-diversity patterns between assemblages of flooded versus nonflooded areas. The specimens were collected with banana-baited traps, and the assemblages recovered in eight wetlands of the southernmost coast of Brazil were compared to those recovered from seven nonflooded areas of the Pampa and Atlantic Forest biomes. A total of 5028 and 2571 individuals encompassing 27 and 37 species were collected in the flooded and nonflooded areas, respectively. The differential species composition patterns presented between these areas was statistically supported, which seems to be related to the lower beta-diversity presented by swamps, especially in regard to dominance patterns. So, the open and climatically harsher environment provided by wetlands possibly constitutes a hostile environment for the entry and, mainly, for the persistence of several native Drosophilidae species, in contrast to some exotic and more plastic species (as Drosophila simulans and Zaprionus indianus. Since the diversity gradient of flooded areas does not seem to be related to the conservation status of the swamp, our results question the use of Drosophilidae species as bioindicators of environmental disturbance and antropic influence in wetlands.

  19. Uncertainty assessment of urban pluvial flood risk in a context of climate change adaptation decision making

    DEFF Research Database (Denmark)

    Arnbjerg-Nielsen, Karsten; Zhou, Qianqian

    2014-01-01

    uncertainty analysis, which can assess and quantify the overall uncertainty in relation to climate change adaptation to urban flash floods. The analysis is based on an uncertainty cascade that by means of Monte Carlo simulations of flood risk assessments incorporates climate change impacts as a key driver......There has been a significant increase in climatic extremes in many regions. In Central and Northern Europe, this has led to more frequent and more severe floods. Along with improved flood modelling technologies this has enabled development of economic assessment of climate change adaptation...... to increasing urban flood risk. Assessment of adaptation strategies often requires a comprehensive risk-based economic analysis of current risk, drivers of change of risk over time, and measures to reduce the risk. However, such studies are often associated with large uncertainties. The uncertainties arise from...

  20. Assessment and Adaptation to Climate Change-Related Floods Risks

    NARCIS (Netherlands)

    Jongman, B.; Winsemius, H.C.; Fraser, S.; Muis, S.; Ward, P.J.

    2018-01-01

    The flooding of rivers and coastlines is the most frequent and damaging of all natural hazards. Between 1980 and 2016, total direct damages exceeded $1.6 trillion, and at least 225,000 people lost their lives. Recent events causing major economic losses include the 2011 river flooding in Thailand

  1. Assessing Stability and Dynamics in Flood Risk Governance

    NARCIS (Netherlands)

    Hegger, D.L.T.; Driessen, P.P.J.; Dieperink, C.; Wiering, M.A.; Raadgever, G.T.; Rijswick, H.F.M.W. van

    2014-01-01

    European urban agglomerations face increasing flood risks due to urbanization and the effects of climate change. These risks are addressed at European, national and regional policy levels. A diversification and alignment of Flood Risk Management Strategies (FRMSs) can make vulnerable urban

  2. Assessment of the effectiveness of flood adaptation strategies for HCMC

    NARCIS (Netherlands)

    Lasage, R.; Veldkamp, T.I.E.; de Moel, H.; Van, T.C.; Phi, H.L.; Vellinga, P.; Aerts, J.C.J.H.

    2014-01-01

    Coastal cities are vulnerable to flooding, and flood risk to coastal cities will increase due to sea-level rise. Moreover, Asian cities in particular are subject to considerable population growth and associated urban developments, increasing this risk even more. Empirical data on vulnerability and

  3. A probabilistic approach for assessing the vulnerability of transportation infrastructure to flooding from sea level rise and storm surge.

    Science.gov (United States)

    Douglas, E. M.; Kirshen, P. H.; Bosma, K.; Watson, C.; Miller, S.; McArthur, K.

    2015-12-01

    There now exists a plethora of information attesting to the reality of our changing climate and its impacts on both human and natural systems. There also exists a growing literature linking climate change impacts and transportation infrastructure (highways, bridges, tunnels, railway, shipping ports, etc.) which largely agrees that the nation's transportation systems are vulnerable. To assess this vulnerability along the coast, flooding due to sea level rise and storm surge has most commonly been evaluated by simply increasing the water surface elevation and then estimating flood depth by comparing the new water surface elevation with the topographic elevations of the land surface. While this rudimentary "bathtub" approach may provide a first order identification of potential areas of vulnerability, accurate assessment requires a high resolution, physically-based hydrodynamic model that can simulate inundation due to the combined effects of sea level rise, storm surge, tides and wave action for site-specific locations. Furthermore, neither the "bathtub" approach nor other scenario-based approaches can quantify the probability of flooding due to these impacts. We developed a high resolution coupled ocean circulation-wave model (ADCIRC/SWAN) that utilizes a Monte Carlo approach for predicting the depths and associated exceedance probabilities of flooding due to both tropical (hurricanes) and extra-tropical storms under current and future climate conditions. This required the development of an entirely new database of meteorological forcing (e.g. pressure, wind speed, etc.) for historical Nor'easters in the North Atlantic basin. Flooding due to hurricanes and Nor'easters was simulated separately and then composite flood probability distributions were developed. Model results were used to assess the vulnerability of the Central Artery/Tunnel system in Boston, Massachusetts to coastal flooding now and in the future. Local and regional adaptation strategies were

  4. 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.

  5. An Integrated Modelling Framework to Assess Flood Risk under Urban Development and Changing Climate

    DEFF Research Database (Denmark)

    Löwe, Roland; Urich, Christian; Sto Domingo, Nina

    Flood risk in cities is strongly affected by the development of the city itself. Many studies focus on changes in the flood hazard as a result of, for example, changed degrees of sealing in the catchment or climatic changes. However, urban developments in flood prone areas can affect the exposure...... to the hazard and thus have large impacts on flood risk. Different urban socio-economic development scenarios, rainfall inputs and options for the mitigation of flood risk, quickly lead to a large number of scenarios that need to be considered in the planning of the development of a city. This calls...... for automated analyses that allow the planner to quickly identify if, when and how infrastructure should be modified. Such analysis, which accounts for the two-way interactions between city development and flood risk, is possible only to a limited extent in existing tools. We have developed a software framework...

  6. Flood risk index pattern assessment: case study in Langat River Basin

    African Journals Online (AJOL)

    This study focus on the creation of flood risk index in the study area based on secondary data derived from the Department of Drainage and Irrigation (DID) since 1982-2012. Based on the result, it shows that the water level is the best variable to be taken for the purposed of flood warning alert system as the result for ...

  7. Urban flash flood vulnerability : spatial assessment and adaptation : a case study in Istanbul, Turkey

    NARCIS (Netherlands)

    Reyes-Acevedo, Martin Alejandro; Flacke, J.; Brussel, M.J.G.

    2011-01-01

    The Ayamama River basin in Istanbul is a densely populated urban area that is frequently impacted by flash floods causing damage to people and infrastructure. The IPCC expects that under climate change conditions, more intense precipitation will occur, leading to a higher risk of flash floods.

  8. Floods characterization: from impact data to quantitative assessment

    Science.gov (United States)

    Llasat, Maria-Carmen; Gilabert, Joan; Llasat-Botija, Montserrat; Marcos, Raül; Quintana-Seguí, Pere; Turco, Marco

    2015-04-01

    This study is based on the following flood databases from Catalonia: INUNGAMA (1900-2010) which considers 372 floods (Llasat et al, 2014), PRESSGAMA (1981-2010) and HISTOGAMA (from XIV Century on) - built as part of SPHERE project and recently updated. These databases store information about flood impacts (among others) and classify them by their severity (catastrophic, extraordinary and ordinary) by means of an indicators matrix based on other studies (i.e. Petrucci et al, 2013; Llasat et al, 2013). On this research we present a comparison between flood impacts, flow data and rainfall data on a Catalan scale and particularly for the basins of Segre, Muga, Ter and Llobregat (Western Mediterranean). From a bottom-up approach, a statistical methodology has been built (trend analysis, measures of position, cumulative distribution functions and geostatistics) in order to identify quantitative thresholds that will make possible to classify the floods. The purpose of this study is to establish generic thresholds for the whole Catalan region, for this we have selected rainfall maximums of flooding episodes stored at INUNGAMA and they have been related to flood categories by boxplot diagrams. Regarding the stream flow, we have established a relation between impacts and return periods at the day when the flow is maximum. The aim is to homogenize and compare the different drainage basins and to obtain general thresholds. It is also presented detailed analyses of relations between flooding episodes, flood classification and weather typing schemes - based in Jenkinson and Collison classification (applied to the Iberian Peninsula by Spellmann, 2000). In this way it could be analyzed whether patterns for the different types of floods exist or not. Finally, this work has pointed out the need of defining a new category for the most severe episodes.

  9. The Use of Sentinel-1 Time-Series Data to Improve Flood Monitoring in Arid Areas

    Directory of Open Access Journals (Sweden)

    Sandro Martinis

    2018-04-01

    Full Text Available Due to the similarity of the radar backscatter over open water and over sand surfaces a reliable near real-time flood mapping based on satellite radar sensors is usually not possible in arid areas. Within this study, an approach is presented to enhance the results of an automatic Sentinel-1 flood processing chain by removing overestimations of the water extent related to low-backscattering sand surfaces using a Sand Exclusion Layer (SEL derived from time-series statistics of Sentinel-1 data sets. The methodology was tested and validated on a flood event in May 2016 at Webi Shabelle River, Somalia and Ethiopia, which has been covered by a time-series of 202 Sentinel-1 scenes within the period June 2014 to May 2017. The approach proved capable of significantly improving the classification accuracy of the Sentinel-1 flood service within this study site. The Overall Accuracy increased by ~5% to a value of 98.5% and the User’s Accuracy increased by 25.2% to a value of 96.0%. Experimental results have shown that the classification accuracy is influenced by several parameters such as the lengths of the time-series used for generating the SEL.

  10. Simultaneous Observation Data of GB-SAR/PiSAR to Detect Flooding in an Urban Area

    Directory of Open Access Journals (Sweden)

    Manabu Watanabe

    2010-01-01

    Full Text Available We analyzed simultaneous observation data with ground-based synthetic aperture radar (GB-SAR and airborne SAR (PiSAR over a flood test site at which a simple house was constructed in a field. The PiSAR σ∘ under flood condition was 0.9 to 3.4 dB higher than that under nonflood condition. GB-SAR gives high spatial resolution as we could identify a single scattering component and a double bounce component from the house. GB-SAR showed that the σ∘ difference between the flooding and nonflooding conditions came from the double bounce scattering. We also confirm that the entropy is a sensitive parameter in the eigenvalue decomposition parameters, if the scattering process is dominated by the double bounce scattering. We conclude that σ∘ and entropy are a good parameter to be used to detect flooding, not only in agricultural and forest regions, but also in urban areas. We also conclude that GB-SAR is a powerful tool to supplement satellite and airborne observation, which has a relatively low spatial resolution.

  11. Simultaneous Observation Data of GB-SAR/PiSAR to Detect Flooding in an Urban Area

    Directory of Open Access Journals (Sweden)

    Shimada Masanobu

    2010-01-01

    Full Text Available Abstract We analyzed simultaneous observation data with ground-based synthetic aperture radar (GB-SAR and airborne SAR (PiSAR over a flood test site at which a simple house was constructed in a field. The PiSAR under flood condition was 0.9 to 3.4 dB higher than that under nonflood condition. GB-SAR gives high spatial resolution as we could identify a single scattering component and a double bounce component from the house. GB-SAR showed that the difference between the flooding and nonflooding conditions came from the double bounce scattering. We also confirm that the entropy is a sensitive parameter in the eigenvalue decomposition parameters, if the scattering process is dominated by the double bounce scattering. We conclude that and entropy are a good parameter to be used to detect flooding, not only in agricultural and forest regions, but also in urban areas. We also conclude that GB-SAR is a powerful tool to supplement satellite and airborne observation, which has a relatively low spatial resolution.

  12. Water quality, sediment, and soil characteristics near Fargo-Moorhead urban areas as affected by major flooding of the Red River of the north

    Science.gov (United States)

    A.C. Guy; T.M. DeSutter; F.X.M. Casey; R. Kolka; H. Hakk

    2012-01-01

    Spring flooding of the Red River of the North (RR) is common, but little information exits on how these flood events affect water and overbank sediment quality within an urban area. With the threat of the spring 2009 flood in the RR predicted to be the largest in recorded history and the concerns about the flooding of farmsteads, outbuildings, garages, and basements,...

  13. Hydrological Modelling using HEC-HMS for Flood Risk Assessment of Segamat Town, Malaysia

    Science.gov (United States)

    Romali, N. S.; Yusop, Z.; Ismail, A. Z.

    2018-03-01

    This paper presents an assessment of the applicability of using Hydrologic Modelling System developed by the Hydrologic Engineering Center (HEC-HMS) for hydrological modelling of Segamat River. The objective of the model application is to assist in the assessment of flood risk by providing the peak flows of 2011 Segamat flood for the generation of flood mapping of Segamat town. The capability of the model was evaluated by comparing the historical observed data with the simulation results of the selected flood events. The model calibration and validation efficiency was verified using Nash-Sutcliffe model efficiency coefficient. The results demonstrate the interest to implement the hydrological model for assessing flood risk where the simulated peak flow result is in agreement with historical observed data. The model efficiency of the calibrated and validated exercises is 0.90 and 0.76 respectively, which is acceptable.

  14. Flood protection structure detection with Lidar: examples on French Mediterranean rivers and coastal areas

    Directory of Open Access Journals (Sweden)

    Trmal Céline

    2016-01-01

    Full Text Available This paper aims at presenting different topographic analysis conducted with GIS software in order to detect flood protection structures, natural or artificial, in river floodplains but also in coastal zones. Those computations are relevant because of the availability of high-resolution lidar digital terrain model (DTM. An automatic detection permits to map the footprint of those structures. Then detailed mapping of structure crest is achieved by implementing a least cost path analysis on DTM but also on other terrain aspects such as the curvature. On coastal zones, the analysis is going further by identifying flood protected areas and the level of protection regarding sea level. This article is illustrated by examples on French Mediterranean rivers and coastal areas.

  15. 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.

  16. Extensive spatio-temporal assessment of flood events by application of pair-copulas

    Directory of Open Access Journals (Sweden)

    M. Schulte

    2015-06-01

    Full Text Available Although the consequences of floods are strongly related to their peak discharges, a statistical classification of flood events that only depends on these peaks may not be sufficient for flood risk assessments. In many cases, the flood risk depends on a number of event characteristics. In case of an extreme flood, the whole river basin may be affected instead of a single watershed, and there will be superposition of peak discharges from adjoining catchments. These peaks differ in size and timing according to the spatial distribution of precipitation and watershed-specific processes of flood formation. Thus, the spatial characteristics of flood events should be considered as stochastic processes. Hence, there is a need for a multivariate statistical approach that represents the spatial interdependencies between floods from different watersheds and their coincidences. This paper addresses the question how these spatial interdependencies can be quantified. Each flood event is not only assessed with regard to its local conditions but also according to its spatio-temporal pattern within the river basin. In this paper we characterise the coincidence of floods by trivariate Joe-copula and pair-copulas. Their ability to link the marginal distributions of the variates while maintaining their dependence structure characterizes them as an adequate method. The results indicate that the trivariate copula model is able to represent the multivariate probabilities of the occurrence of simultaneous flood peaks well. It is suggested that the approach of this paper is very useful for the risk-based design of retention basins as it accounts for the complex spatio-temporal interactions of floods.

  17. Analysis of Hydrological Sensitivity for Flood Risk Assessment

    Directory of Open Access Journals (Sweden)

    Sanjay Kumar Sharma

    2018-02-01

    Full Text Available In order for the Indian government to maximize Integrated Water Resource Management (IWRM, the Brahmaputra River has played an important role in the undertaking of the Pilot Basin Study (PBS due to the Brahmaputra River’s annual regional flooding. The selected Kulsi River—a part of Brahmaputra sub-basin—experienced severe floods in 2007 and 2008. In this study, the Rainfall-Runoff-Inundation (RRI hydrological model was used to simulate the recent historical flood in order to understand and improve the integrated flood risk management plan. The ultimate objective was to evaluate the sensitivity of hydrologic simulation using different Digital Elevation Model (DEM resources, coupled with DEM smoothing techniques, with a particular focus on the comparison of river discharge and flood inundation extent. As a result, the sensitivity analysis showed that, among the input parameters, the RRI model is highly sensitive to Manning’s roughness coefficient values for flood plains, followed by the source of the DEM, and then soil depth. After optimizing its parameters, the simulated inundation extent showed that the smoothing filter was more influential than its simulated discharge at the outlet. Finally, the calibrated and validated RRI model simulations agreed well with the observed discharge and the Moderate Imaging Spectroradiometer (MODIS-detected flood extents.

  18. Regional flood hazard assessment of the Paducah and Portsmouth Gaseous Diffusion Plants

    International Nuclear Information System (INIS)

    Johnson, R.O.; Wang, J.C.; Lee, D.W.

    1991-01-01

    Regional flood-hazard assessments performed for the Paducah and Portsmouth Gaseous Diffusion Plants are reviewed, compared, and contrasted to determine the relationship of probable maximum flood methodology with respect to US Department of Energy design and evaluation guidelines. The Paducah assessment was carried out using probable minimum flood methodology, while the Portsmouth assessment utilized probabilistic techniques. Results indicated that regional flooding along nearby rivers would not inundate either plant, and that the guidelines were satisfied. A comparison of results indicated that the probable minimum flood recurrence interval associated with the Paducah assessment exceeded the 10,000-year requirement of the guidelines, while recurrence intervals obtained in the Portsmouth assessment could be above or below 10,000 years depending on the choice of the probabilistic model used to perform the assessment. It was concluded, based on an analysis of two data points, that smaller watersheds driven by single event storms could be assessed using probabilistic techniques, while probable maximum flood methodology could be applied to larger drainage basins flooded by storm sequences

  19. Assessing the impact of uncertainty on flood risk estimates with reliability analysis using 1-D and 2-D hydraulic models

    Directory of Open Access Journals (Sweden)

    L. Altarejos-García

    2012-07-01

    Full Text Available This paper addresses the use of reliability techniques such as Rosenblueth's Point-Estimate Method (PEM as a practical alternative to more precise Monte Carlo approaches to get estimates of the mean and variance of uncertain flood parameters water depth and velocity. These parameters define the flood severity, which is a concept used for decision-making in the context of flood risk assessment. The method proposed is particularly useful when the degree of complexity of the hydraulic models makes Monte Carlo inapplicable in terms of computing time, but when a measure of the variability of these parameters is still needed. The capacity of PEM, which is a special case of numerical quadrature based on orthogonal polynomials, to evaluate the first two moments of performance functions such as the water depth and velocity is demonstrated in the case of a single river reach using a 1-D HEC-RAS model. It is shown that in some cases, using a simple variable transformation, statistical distributions of both water depth and velocity approximate the lognormal. As this distribution is fully defined by its mean and variance, PEM can be used to define the full probability distribution function of these flood parameters and so allowing for probability estimations of flood severity. Then, an application of the method to the same river reach using a 2-D Shallow Water Equations (SWE model is performed. Flood maps of mean and standard deviation of water depth and velocity are obtained, and uncertainty in the extension of flooded areas with different severity levels is assessed. It is recognized, though, that whenever application of Monte Carlo method is practically feasible, it is a preferred approach.

  20. Application of gis on determination of flood prone areas and critical arterial road network by using chaid method in bandung area

    Directory of Open Access Journals (Sweden)

    Darwin

    2018-01-01

    Full Text Available Floods in Bandung area often occur when the rainfall is high then the water volume exceed the capacity of Citarum watershed. Floods cause economic and social losses. The purpose of this research is to get the GIS application model in the estimation of puddle area and road network in Bandung Metropolitan Area has disturbed.Geospatial map preparation methodology used statistical data from 11041 flood points, which divided into two groups, 7729 flood points to estimate the decision tree model and 3312 flood points to validate the model. The process of making flood vulnerability maps is approached by Chi-square Automatic Interaction Detection (CHAID method, and validation using Receiver Operating Characteristic (ROC method. Validation results in the area under the curve with a value of 93.1% for success rate and 92.7% for the prediction level.Chaid result is class 0 - 0,047 covering 76,68% area; Grades of 0.047-0.307 include 5.37%; Grades 0.307 - 0.599 (Low covering 5.36%; Grades 0.599 to 0.4444 include 5.31% and grade 0.844-1 (high covering 7.27% of the research area. Flood-prone road network is Link from Rancaekek (Area of PT Kahatex, link from Solokan Jeruk (Cicalengka-Majalaya, Link Baleendah, and linkDayeuhkolot (M.Toha - Andir

  1. Lung ventilation injures areas with discrete alveolar flooding, in a surface tension-dependent fashion.

    Science.gov (United States)

    Wu, You; Kharge, Angana Banerjee; Perlman, Carrie E

    2014-10-01

    With proteinaceous-liquid flooding of discrete alveoli, a model of the edema pattern in the acute respiratory distress syndrome, lung inflation over expands aerated alveoli adjacent to flooded alveoli. Theoretical considerations suggest that the overexpansion may be proportional to surface tension, T. Yet recent evidence indicates proteinaceous edema liquid may not elevate T. Thus whether the overexpansion is injurious is not known. Here, working in the isolated, perfused rat lung, we quantify fluorescence movement from the vasculature to the alveolar liquid phase as a measure of overdistension injury to the alveolar-capillary barrier. We label the perfusate with fluorescence; micropuncture a surface alveolus and instill a controlled volume of nonfluorescent liquid to obtain a micropunctured-but-aerated region (control group) or a region with discrete alveolar flooding; image the region at a constant transpulmonary pressure of 5 cmH2O; apply five ventilation cycles with a positive end-expiratory pressure of 0-20 cmH2O and tidal volume of 6 or 12 ml/kg; return the lung to a constant transpulmonary pressure of 5 cmH2O; and image for an additional 10 min. In aerated areas, ventilation is not injurious. With discrete alveolar flooding, all ventilation protocols cause sustained injury. Greater positive end-expiratory pressure or tidal volume increases injury. Furthermore, we determine T and find injury increases with T. Inclusion of either plasma proteins or Survanta in the flooding liquid does not alter T or injury. Inclusion of 2.7-10% albumin and 1% Survanta together, however, lowers T and injury. Contrary to expectation, albumin inclusion in our model facilitates exogenous surfactant activity. Copyright © 2014 the American Physiological Society.

  2. Assessing flood risk at the global scale: model setup, results, and sensitivity

    International Nuclear Information System (INIS)

    Ward, Philip J; Jongman, Brenden; Weiland, Frederiek Sperna; Winsemius, Hessel C; Bouwman, Arno; Ligtvoet, Willem; Van Beek, Rens; Bierkens, Marc F P

    2013-01-01

    Globally, economic losses from flooding exceeded $19 billion in 2012, and are rising rapidly. Hence, there is an increasing need for global-scale flood risk assessments, also within the context of integrated global assessments. We have developed and validated a model cascade for producing global flood risk maps, based on numerous flood return-periods. Validation results indicate that the model simulates interannual fluctuations in flood impacts well. The cascade involves: hydrological and hydraulic modelling; extreme value statistics; inundation modelling; flood impact modelling; and estimating annual expected impacts. The initial results estimate global impacts for several indicators, for example annual expected exposed population (169 million); and annual expected exposed GDP ($1383 billion). These results are relatively insensitive to the extreme value distribution employed to estimate low frequency flood volumes. However, they are extremely sensitive to the assumed flood protection standard; developing a database of such standards should be a research priority. Also, results are sensitive to the use of two different climate forcing datasets. The impact model can easily accommodate new, user-defined, impact indicators. We envisage several applications, for example: identifying risk hotspots; calculating macro-scale risk for the insurance industry and large companies; and assessing potential benefits (and costs) of adaptation measures. (letter)

  3. Uncertainty assessment of climate change adaptation using an economic pluvial flood risk framework

    DEFF Research Database (Denmark)

    Zhou, Qianqian; Arnbjerg-Nielsen, Karsten

    2012-01-01

    It is anticipated that climate change is likely to lead to an increasing risk level of flooding in cities in northern Europe. One challenging question is how to best address the increasing flood risk and assess the costs and benefits of adapting to such changes. We established an integrated...... approach for identification and assessment of climate change adaptation options by incorporating climate change impacts, flood inundation modelling, economic tool and risk assessment and management. The framework is further extended and adapted by embedding a Monte Carlo simulation to estimate the total...

  4. Flood Risk Assessment on Selected Critical Infrastructure in Kota Marudu Town, Sabah, Malaysia

    Directory of Open Access Journals (Sweden)

    Ayog Janice Lynn

    2017-01-01

    Full Text Available This study investigates the risk of flood on selected critical infrastructure in a flood-prone catchment in Sabah, Malaysia. Kota Marudu, located in the Bandau floodplain, one of the Sabah’s northern water catchments, was selected as the study site due to its frequent flood occurrence and large floodplain coverage. Two of its largest rivers, namely Sungai Bongon and Sungai Bandau, tends to flood during rainy season and cause temporary displacements of thousands of people living in the floodplain. A total of 362 respondents participated in the questionnaire survey in order to gather information on historical flood occurrence. Three flood depth groups were determined, which are 1 less than 0.3 meter, 2 0.3 – 0.6 meter and 3 more than 0.6 meter, while three categories of critical infrastructure were defined, namely transportation system, communication system and buildings. It is found that the transportation system encounters the most severe impact as flood inundation increases, where 92% of the respondents believe that the transportation access should be abandoned when flood depth is more than 0.6m. The findings of this study will be used for detailed risk assessment, specifically on the vulnerability of the critical infrastructures to flood in this floodplain.

  5. Urban Flooding Analysis Using Radar Rainfall Data and 2-D Hydrodynamic Model: A Pilot Study of Back Cover Area, Portland, Maine

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Eugene [Argonne National Lab. (ANL), Argonne, IL (United States); Pierce, Julia [Argonne National Lab. (ANL), Argonne, IL (United States); Mahat, Vinod [Argonne National Lab. (ANL), Argonne, IL (United States); Jared, Alissa [Argonne National Lab. (ANL), Argonne, IL (United States); Collis, Scott [Argonne National Lab. (ANL), Argonne, IL (United States); Verner, Duane [Argonne National Lab. (ANL), Argonne, IL (United States); Wall, Thomas [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-11-01

    This project is a part of the Regional Resiliency Assessment Program, led by the Department of Homeland Security, to address flooding hazards of regional significance for Portland, Maine. The pilot study was performed by Argonne National Laboratory to identify differences in spatial rainfall distributions between the radar-derived and rain-gauge rainfall datasets and to evaluate their impacts on urban flooding. The flooding impact analysis utilized a high-resolution 2-dimensional (2-D) hydrodynamic model (15 ft by 15 ft) incorporating the buildings, streets, stream channels, hydraulic structures, an existing city storm drain system, and assuming a storm surge along the coast coincident with a heavy rainfall event. Two historical storm events from April 16, 2007, and September 29, 2015, were selected for evaluation. The radar-derived rainfall data at a 200-m resolution provide spatially-varied rainfall patterns with a wide range of intensities for each event. The resultant maximum flood depth using data from a single rain gauge within the study area could be off (either under- or over-estimated) by more than 10% in the 2007 storm and more than 60% in the 2015 storm compared to the radar-derived rainfall data. The model results also suggest that the inundation area with a flow depth at or greater than 0.5 ft could reach 11% (2007 storm) and 17% (2015 storm) of the total study area, respectively. The lowland areas within the neighborhoods of North Deering, East Deering, East and West Baysides and northeastern Parkside, appear to be more vulnerable to the flood hazard in both storm events. The high-resolution 2-D hydrodynamic model with high-resolution radar-derived rainfall data provides an excellent tool for detailed urban flood analysis and vulnerability assessment. The model developed in this study could be potentially used to evaluate any proposed mitigation measures and optimize their effects in the future for Portland, ME.

  6. Identification of flooded area from satellite images using Hybrid Kohonen Fuzzy C-Means sigma classifier

    Directory of Open Access Journals (Sweden)

    Krishna Kant Singh

    2017-06-01

    Full Text Available A novel neuro fuzzy classifier Hybrid Kohonen Fuzzy C-Means-σ (HKFCM-σ is proposed in this paper. The proposed classifier is a hybridization of Kohonen Clustering Network (KCN with FCM-σ clustering algorithm. The network architecture of HKFCM-σ is similar to simple KCN network having only two layers, i.e., input and output layer. However, the selection of winner neuron is done based on FCM-σ algorithm. Thus, embedding the features of both, a neural network and a fuzzy clustering algorithm in the classifier. This hybridization results in a more efficient, less complex and faster classifier for classifying satellite images. HKFCM-σ is used to identify the flooding that occurred in Kashmir area in September 2014. The HKFCM-σ classifier is applied on pre and post flooding Landsat 8 OLI images of Kashmir to detect the areas that were flooded due to the heavy rainfalls of September, 2014. The classifier is trained using the mean values of the various spectral indices like NDVI, NDWI, NDBI and first component of Principal Component Analysis. The error matrix was computed to test the performance of the method. The method yields high producer’s accuracy, consumer’s accuracy and kappa coefficient value indicating that the proposed classifier is highly effective and efficient.

  7. USING GIS TO IDENTIFY POTENTIAL AREAS SUSCEPTIBLE TO FLOOD. CASE STUDY: SOLONEŢ RIVER

    Directory of Open Access Journals (Sweden)

    V. TIPLEA

    2011-03-01

    Full Text Available Using GIS to Identify Potential Areas Susceptible to Flood. Case Study: Soloneţ River. In this study, we aim to analyze the impact of different peak flows in territory and also a better understanding of the dynamic of a river flow. The methodology used for flood zone delimitation is based on a quantitative analysis model which requires the use of mathematical, physical and statistical operations in order to emphasize the relations between the different variables that were implied (discharges, grain size, terrain morphology, soil saturation, vegetation etc.. The results cannot be expected to be completely accurate but can provide a good representation of the process. Validation of results will inevitably be difficult and should be measured in the field. The information resulting from this study could be useful for raising awareness about both hazards and possible mitigation measure, a key component of disaster risk reduction planning.

  8. The Application Modular Floating Pontoon to Support Floods Disaster Evacuation System in Heavy Populated Residential Area

    Directory of Open Access Journals (Sweden)

    Ahmad Fauzan Zakki

    2014-10-01

    Full Text Available During floods disaster in the heavy populated residential area, the lack of existing life saving appliances system such as rubber boat and wooden boat were not able to evacuate the disaster victims spontaneously in mass. The condition might be explained since the rubber boat and wooden boat have limited occupant capacity. Based on the conditions, the main objectives of the research are focused on the evaluation of the application of modular floating pontoon as multipurpose floating equipment to support floods disaster evacuation process. The investigation of the modular floating pontoon performance such as hydrostatics characteristics, the equilibrium condition and the intact stability was studied using strip theory and Krylov’s method. Furthermore, the strength analysis of the modular floating pontoon structure was calculated using finite element method. The results show that the modular floating pontoon is reliable to support the evacuation process.

  9. Hybrid artificial intelligence approach based on neural fuzzy inference model and metaheuristic optimization for flood susceptibilitgy modeling in a high-frequency tropical cyclone area using GIS

    Science.gov (United States)

    Tien Bui, Dieu; Pradhan, Biswajeet; Nampak, Haleh; Bui, Quang-Thanh; Tran, Quynh-An; Nguyen, Quoc-Phi

    2016-09-01

    This paper proposes a new artificial intelligence approach based on neural fuzzy inference system and metaheuristic optimization for flood susceptibility modeling, namely MONF. In the new approach, the neural fuzzy inference system was used to create an initial flood susceptibility model and then the model was optimized using two metaheuristic algorithms, Evolutionary Genetic and Particle Swarm Optimization. A high-frequency tropical cyclone area of the Tuong Duong district in Central Vietnam was used as a case study. First, a GIS database for the study area was constructed. The database that includes 76 historical flood inundated areas and ten flood influencing factors was used to develop and validate the proposed model. Root Mean Square Error (RMSE), Mean Absolute Error (MAE), Receiver Operating Characteristic (ROC) curve, and area under the ROC curve (AUC) were used to assess the model performance and its prediction capability. Experimental results showed that the proposed model has high performance on both the training (RMSE = 0.306, MAE = 0.094, AUC = 0.962) and validation dataset (RMSE = 0.362, MAE = 0.130, AUC = 0.911). The usability of the proposed model was evaluated by comparing with those obtained from state-of-the art benchmark soft computing techniques such as J48 Decision Tree, Random Forest, Multi-layer Perceptron Neural Network, Support Vector Machine, and Adaptive Neuro Fuzzy Inference System. The results show that the proposed MONF model outperforms the above benchmark models; we conclude that the MONF model is a new alternative tool that should be used in flood susceptibility mapping. The result in this study is useful for planners and decision makers for sustainable management of flood-prone areas.

  10. Effects of sea level rise, land subsidence, bathymetric change and typhoon tracks on storm flooding in the coastal areas of Shanghai.

    Science.gov (United States)

    Wang, Jun; Yi, Si; Li, Mengya; Wang, Lei; Song, Chengcheng

    2018-04-15

    We compared the effects of three key environmental factors of coastal flooding: sea level rise (SLR), land subsidence (LS) and bathymetric change (BC) in the coastal areas of Shanghai. We use the hydrological simulation model MIKE 21 to simulate flood magnitudes under multiple scenarios created from combinations of the key environmental factors projected to year 2030 and 2050. Historical typhoons (TC9711, TC8114, TC0012, TC0205 and TC1109), which caused extremely high surges and considerable losses, were selected as reference tracks to generate potential typhoon events that would make landfalls in Shanghai (SHLD), in the north of Zhejiang (ZNLD) and moving northwards in the offshore area of Shanghai (MNS) under those scenarios. The model results provided assessment of impact of single and compound effects of the three factors (SLR, LS and BC) on coastal flooding in Shanghai for the next few decades. Model simulation showed that by the year 2030, the magnitude of storm flooding will increase due to the environmental changes defined by SLR, LS, and BC. Particularly, the compound scenario of the three factors will generate coastal floods that are 3.1, 2.7, and 1.9 times greater than the single factor change scenarios by, respectively, SLR, LS, and BC. Even more drastically, in 2050, the compound impact of the three factors would be 8.5, 7.5, and 23.4 times of the single factors. It indicates that the impact of environmental changes is not simple addition of the effects from individual factors, but rather multiple times greater of that when the projection time is longer. We also found for short-term scenarios, the bathymetry change is the most important factor for the changes in coastal flooding; and for long-term scenarios, sea level rise and land subsidence are the major factors that coastal flood prevention and management should address. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. 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

  12. Flood warnings in coastal areas: how do experience and information influence responses to alert services?

    Science.gov (United States)

    Pescaroli, G.; Magni, M.

    2015-04-01

    Many studies discuss the economic and technical aspects of flood warnings. Less attention has been given to the social and behavioural patterns that affect alert services. In particular, the literature focuses on warnings activated in river basins or marine environments without providing clear evidence on Mediterranean coastal areas, even though these are subjected to growing flood risk related to climate change. This paper is a first attempt to bridge this gap. Our research develops an in-depth analysis of the village of Cesenatico on the Adriatic Sea coast. Here the municipality adopted two complementary warning systems: a siren and an alert via short message service (SMS). The analysis focuses on a survey conducted in 2011 and 2012 with 228 participants. The relationships between social and behavioural variables and warning services are investigated as well as flood preparedness and information dissemination. Qualitative evidence from informal interviews is used to support the understanding of key responses. The conclusions show how different social and behavioural patterns can influence the effectiveness and use of warning systems, regardless of the technology adopted and the structural mitigation measures implemented. Education, training and accountability are seen to be critical elements for implementation. Finally, the statistical output is used to suggest new questions and new directions for research.

  13. Flood warnings in coastal areas: how do social and behavioural patterns influence alert services?

    Science.gov (United States)

    Pescaroli, G.; Magni, M.

    2015-01-01

    Many studies discuss the economic and technical aspects of flood warnings. Less attention has been given to the social and psychological patterns that affect alert services. In particular, the literature focuses on warnings activated in river basins or marine environments without providing clear evidence of relevance to Mediterranean coastal areas, even though these are subjected to growing flood risk related to climate change. This paper is a first attempt to bridge this gap. Our research develops an in- depth analysis of the village of Cesenatico on the Adriatic Sea coast. Here the municipality adopted two complementary warning systems: a siren and an alert via Short Message Service (SMS). The analysis focuses on a survey conducted in 2011 and 2012 with 228 participants. The relationships between social and behavioural variables and warning services are investigated, and so are flood preparedness and information dissemination. Qualitative evidence from informal interviews is used to support the understanding of key responses. The conclusions show how different social and behavioural patterns can influence the effectiveness and use of warning systems, regardless of the technology adopted and the structural mitigation measures implemented. Education, training and accountability are seen to be critical elements for improvement. Finally, the statistical output is used to suggest new questions and new directions for research.

  14. Flash floods along the Italian coastal areas: examples from Pozzuoli city, Campania, Italy

    Science.gov (United States)

    Esposito, Giuseppe; Grimaldi, Giuseppe; Matano, Fabio; Mazzola, Salvatore; Sacchi, Marco

    2014-05-01

    The Italian western coastal areas are the most exposed in the country to low-pressure systems coming from the central-western Mediterranean Sea and Atlantic Ocean. In the last years, many Italian coastal villages were struck by floods and flow processes triggered by high-intensity and short-duration rainfall, typical of flash flood events. In the Campania region (SW Italy) a series of events has caused several fatalities and heavy damages in the last decades, i.e. the flash floods of Casamicciola - Ischia Island (10/11/2009 - 1 fatality) and Atrani (9/9/2010 - 1 fatality). In this work we describe the rainfall properties and the ground effects of the 2009, 2010 and 2011 flash floods which involved the city of Pozzuoli, along the Campi Flegrei coast, where a catastrophic flood event (13 fatalities) is reported in 1918 in the AVI Project database. Rainfall data were measured at a sampling rate of 10 minutes by a regional Civil Protection rain gauge located in the city of Pozzuoli near the areas struck by the flash flood effects. In order to analyze the extreme features of the rainstorms and compare them, we have considered the 1-hour maximum rainfall amount and the 10-min peak storm intensity value for each event. The first rainstorm occurred on 14 September 2009; it was characterized by a 1-hour maximum rainfall amount of 34.4 mm and a 10-min peak storm intensity of 57.6 mm/h. The second rainstorm occurred on 30 July 2010; it was characterized by a 1-hour maximum rainfall amount of 40.6 mm and a 10-min peak storm intensity of 126 mm/h. The third rainstorm occurred on 06 November 2011; it was characterized by a 1-hour maximum rainfall amount of 44.2 mm and a 10-min peak storm intensity of 67.2 mm/h. The three described rainstorms all triggered erosional processes and shallow landslides in the upper part of the Pozzuoli drainage basin that supplied sheet flows and hyperconcentrated flows downstream, with severe damage to the human structures built near or inside the

  15. Vehicles instability criteria for flood risk assessment of a street network

    Directory of Open Access Journals (Sweden)

    C. Arrighi

    2016-05-01

    Full Text Available The mutual interaction between floods and human activity is a process, which has been evolving over history and has shaped flood risk pathways. In developed countries, many events have illustrated that the majority of the fatalities during a flood occurs in a vehicle, which is considered as a safe shelter but it may turn into a trap for several combinations of water depth and velocity. Thus, driving a car in floodwaters is recognized as the most crucial aggravating factor for people safety. On the other hand, the entrainment of vehicles may locally cause obstructions to the flow and induce the collapse of infrastructures. Flood risk to vehicles can be defined as the combination of the probability of a vehicle of being swept away (i.e. the hazard and the actual traffic/parking density, i.e. the vulnerability. Hazard for vehicles can be assessed through the spatial identification and mapping of the critical conditions for vehicles incipient motion. This analysis requires a flood map with information on water depth and velocity and consistent instability criteria accounting for flood and vehicles characteristics. Vulnerability is evaluated thanks to the road network and traffic data. Therefore, vehicles flood risk mapping can support people's education and management practices in order to reduce the casualties. In this work, a flood hazard classification for vehicles is introduced and an application to a real case study is presented and discussed.

  16. Vehicles instability criteria for flood risk assessment of a street network

    Science.gov (United States)

    Arrighi, Chiara; Huybrechts, Nicolas; Ouahsine, Abdellatif; Chassé, Patrick; Oumeraci, Hocine; Castelli, Fabio

    2016-05-01

    The mutual interaction between floods and human activity is a process, which has been evolving over history and has shaped flood risk pathways. In developed countries, many events have illustrated that the majority of the fatalities during a flood occurs in a vehicle, which is considered as a safe shelter but it may turn into a trap for several combinations of water depth and velocity. Thus, driving a car in floodwaters is recognized as the most crucial aggravating factor for people safety. On the other hand, the entrainment of vehicles may locally cause obstructions to the flow and induce the collapse of infrastructures. Flood risk to vehicles can be defined as the combination of the probability of a vehicle of being swept away (i.e. the hazard) and the actual traffic/parking density, i.e. the vulnerability. Hazard for vehicles can be assessed through the spatial identification and mapping of the critical conditions for vehicles incipient motion. This analysis requires a flood map with information on water depth and velocity and consistent instability criteria accounting for flood and vehicles characteristics. Vulnerability is evaluated thanks to the road network and traffic data. Therefore, vehicles flood risk mapping can support people's education and management practices in order to reduce the casualties. In this work, a flood hazard classification for vehicles is introduced and an application to a real case study is presented and discussed.

  17. Hydrological change: Towards a consistent approach to assess changes on both floods and droughts

    Science.gov (United States)

    Quesada-Montano, Beatriz; Di Baldassarre, Giuliano; Rangecroft, Sally; Van Loon, Anne F.

    2018-01-01

    Several studies have found that the frequency, magnitude and spatio-temporal distribution of droughts and floods have significantly increased in many regions of the world. Yet, most of the methods used in detecting trends in hydrological extremes 1) focus on either floods or droughts, and/or 2) base their assessment on characteristics that, even though useful for trend identification, cannot be directly used in decision making, e.g. integrated water resources management and disaster risk reduction. In this paper, we first discuss the need for a consistent approach to assess changes on both floods and droughts, and then propose a method based on the theory of runs and threshold levels. Flood and drought changes were assessed in terms of frequency, length and surplus/deficit volumes. This paper also presents an example application using streamflow data from two hydrometric stations along the Po River basin (Italy), Piacenza and Pontelagoscuro, and then discuss opportunities and challenges of the proposed method.

  18. Evaluation of the Benefit of Flood Reduction by Artificial Groundwater Recharge Lake Operation in a Coastal Area

    Science.gov (United States)

    Chen, Ching-Nuo; Tsai, Chih-Heng

    2017-04-01

    Inundation disasters often occur in the southwestern coastal plains of Taiwan. The coastal plains suffers mostly from land-subsidence, surface water is difficult to be drained during the typhoon period, leading to more severe flood disasters. Global climate warming has become more significant, which in turn has resulted in the increase in amplitude and frequency of climate change related disasters. In addition, climate change also induces a rise in sea water level year by year. The rise in sea water level does not only weakens the function of existing drainage system but also increases tidal levels and storm tide levels, which increases the probability and amount of inundation disasters. The serious land subsidence area at Linbian river basin was selected as the study area. An artificial groundwater recharge lake has been set up in Linbian river basin by Pingtung government. The development area of this lake is 58 hectare and the storage volume is 2.1 million cubic meters (210 × 104m3). The surface water from Linbian basin during a wet season is led into the artificial groundwater recharge lake by water diversion project, and then employ special hydro-geological conditions of the area for groundwater recharge, increase groundwater supply and decrease land subsidence rate, and incidentally some of the flood diversion, detention, reduce flooding. In this study, a Real-time Interactive Inundation Model is applied to simulate different flooding storage volume and gate operations to estimate the benefits of flood mitigation. According to the simulation results, the hydrograph shape, peak-flow reduction and time lag to peak of the flood reduction hydrograph into the lake are apparently different for each case of different gate operation at the same storage volume. Therefore, the effect of flood control and disaster mitigation is different. The flood control and disaster mitigation benefits are evaluated by different operation modes, which provide decision makers to

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

    Directory of Open Access Journals (Sweden)

    Tumpale Sakijege

    2012-08-01

    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.

  20. Optimal investment and location decisions of a firm in a flood risk area using Impulse Control Theory

    Science.gov (United States)

    Grames, Johanna; Grass, Dieter; Kort, Peter; Prskawetz, Alexia

    2017-04-01

    Flooding events can affect businesses close to rivers, lakes or coasts. This paper provides a partial equilibrium model which helps to understand the optimal location choice for a firm in flood risk areas and its investment strategies. How often, when and how much are firms willing to invest in flood risk protection measures? We apply Impulse Control Theory to solve the model analytically and develop a continuation algorithm to solve the model numerically. Firms always invest in flood defense. The investment increases the higher the flood risk and the more firms also value the future, i.e. the more sustainable they plan. Investments in production capital follow a similar path. Hence, planning in a sustainable way leads to economic growth. Sociohydrological feedbacks are crucial for the location choice of the firm, whereas different economic situations have an impact on investment strategies. If flood defense is already present, e.g. built up by the government, firms move closer to the water and invest less in flood defense, which allows firms to accrue higher expected profits. Firms with a large initial production capital surprisingly try not to keep their market advantage, but rather reduce flood risk by reducing exposed production capital.

  1. Assessment of floodplain vulnerability during extreme Mississippi River flood 2011.

    Science.gov (United States)

    Goodwell, Allison E; Zhu, Zhenduo; Dutta, Debsunder; Greenberg, Jonathan A; Kumar, Praveen; Garcia, Marcelo H; Rhoads, Bruce L; Holmes, Robert R; Parker, Gary; Berretta, David P; Jacobson, Robert B

    2014-01-01

    Regional change in the variability and magnitude of flooding could be a major consequence of future global climate change. Extreme floods have the capacity to rapidly transform landscapes and expose landscape vulnerabilities through highly variable spatial patterns of inundation, erosion, and deposition. We use the historic activation of the Birds Point-New Madrid Floodway during the Mississippi and Ohio River Flooding of 2011 as a scientifically unique stress experiment to analyze indicators of floodplain vulnerability. We use pre- and postflood airborne Light Detection and Ranging data sets to locate erosional and depositional hotspots over the 540 km(2) agricultural Floodway. While riparian vegetation between the river and the main levee breach likely prevented widespread deposition, localized scour and deposition occurred near the levee breaches. Eroded gullies nearly 1 km in length were observed at a low ridge of a relict meander scar of the Mississippi River. Our flow modeling and spatial mapping analysis attributes this vulnerability to a combination of erodible soils, flow acceleration associated with legacy fluvial landforms, and a lack of woody vegetation to anchor soil and enhance flow resistance. Results from this study could guide future mitigation and adaptation measures in cases of extreme flooding.

  2. Flood Risk Index Assessment in Johor River Basin

    International Nuclear Information System (INIS)

    Ahmad Shakir Mohd Saudi; Hafizan Juahir; Azman Azid; Fazureen Azaman; Ahmad Shakir Mohd Saudi

    2015-01-01

    This study is focusing on constructing the flood risk index in the Johor river basin. The application of statistical methods such as factor analysis (FA), statistical process control (SPC) and artificial neural network (ANN) had revealed the most efficient flood risk index. The result in FA was water level has correlation coefficient of 0.738 and the most practicable variable to be used for the warning alert system. The upper control limits (UCL) for the water level in the river basin Johor is 4.423 m and the risk index for the water level has been set by this method consisting of 0-100.The accuracy of prediction has been evaluated by using ANN and the accuracy of the test result was R"2 = 0.96408 with RMSE= 2.5736. The future prediction for UCL in Johor river basin has been predicted and the value was 3.75 m. This model can shows the current and future prediction for flood risk index in the Johor river basin and can help local authorities for flood control and prevention of the state of Johor. (author)

  3. A national framework for flood forecasting model assessment for use in operations and investment planning over England and Wales

    Science.gov (United States)

    Moore, Robert J.; Wells, Steven C.; Cole, Steven J.

    2016-04-01

    It has been common for flood forecasting systems to be commissioned at a catchment or regional level in response to local priorities and hydrological conditions, leading to variety in system design and model choice. As systems mature and efficiencies of national management are sought, there can be a drive towards system rationalisation, gaining an overview of model performance and consideration of simplification through model-type convergence. Flood forecasting model assessments, whilst overseen at a national level, may be commissioned and managed at a catchment and regional level, take a variety of forms and be large in number. This presents a challenge when an integrated national assessment is required to guide operational use of flood forecasts and plan future investment in flood forecasting models and supporting hydrometric monitoring. This contribution reports on how a nationally consistent framework for flood forecasting model performance has been developed to embrace many past, ongoing and future assessments for local river systems by engineering consultants across England & Wales. The outcome is a Performance Summary for every site model assessed which, on a single page, contains relevant catchment information for context, a selection of overlain forecast and observed hydrographs and a set of performance statistics with associated displays of novel condensed form. One display provides performance comparison with other models that may exist for the site. The performance statistics include skill scores for forecasting events (flow/level threshold crossings) of differing severity/rarity, indicating their probability and likely timing, which have real value in an operational setting. The local models assessed can be of any type and span rainfall-runoff (conceptual and transfer function) and flow routing (hydrological and hydrodynamic) forms. Also accommodated by the framework is the national G2G (Grid-to-Grid) distributed hydrological model, providing area

  4. Framework for economic pluvial flood risk assessment considering climate change effects and adaptation benefits

    DEFF Research Database (Denmark)

    Zhou, Qianqian; Mikkelsen, Peter Steen; Halsnæs, Kirsten

    2012-01-01

    Climate change is likely to affect the water cycle by influencing the precipitation patterns. It is important to integrate the anticipated changes into the design of urban drainage in response to the increased risk level in cities. This paper presents a pluvial flood risk assessment framework...... to identify and assess adaptation options in the urban context. An integrated approach is adopted by incorporating climate change impact assessment, flood inundation modeling, economic tool, and risk assessment, hereby developing a step-by-step process for cost-benefit assessment of climate change adaptation...

  5. FLIRE DSS: A web tool for the management of floods and wildfires in urban and periurban areas

    Science.gov (United States)

    Kochilakis, Giorgos; Poursanidis, Dimitris; Chrysoulakis, Nektarios; Varella, Vassiliki; Kotroni, Vassiliki; Eftychidis, Giorgos; Lagouvardos, Kostas; Papathanasiou, Chrysoula; Karavokyros, George; Aivazoglou, Maria; Makropoulos, Christos; Mimikou, Maria

    2016-01-01

    A web-based Decision Support System, named FLIRE DSS, for combined forest fire control and planning as well as flood risk management, has been developed and is presented in this paper. State of the art tools and models have been used in order to enable Civil Protection agencies and local stakeholders to take advantage of the web based DSS without the need of local installation of complex software and their maintenance. Civil protection agencies can predict the behavior of a fire event using real time data and in such a way plan its efficient elimination. Also, during dry periods, agencies can implement "what-if" scenarios for areas that are prone to fire and thus have available plans for forest fire management in case such scenarios occur. Flood services include flood maps and flood-related warnings and become available to relevant authorities for visualization and further analysis on a daily basis. When flood warnings are issued, relevant authorities may proceed to efficient evacuation planning for the areas that are likely to flood and thus save human lives. Real-time weather data from ground stations provide the necessary inputs for the calculation of the fire model in real-time, and a high resolution weather forecast grid supports flood modeling as well as the development of "what-if" scenarios for the fire modeling. All these can be accessed by various computer sources including PC, laptop, Smartphone and tablet either by normal network connection or by using 3G and 4G cellular network. The latter is important for the accessibility of the FLIRE DSS during firefighting or rescue operations during flood events. All these methods and tools provide the end users with the necessary information to design an operational plan for the elimination of the fire events and the efficient management of the flood events in almost real time. Concluding, the FLIRE DSS can be easily transferred to other areas with similar characteristics due to its robust architecture and its

  6. 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

  7. Three dimensional numerical modeling of flow and pollutant transport in a flooding area of 2008 US Midwest Flood

    Science.gov (United States)

    This paper presents the development and application of a three-dimensional numerical model for simulating the flow field and pollutant transport in a flood zone near the confluence of the Mississippi River and Iowa River in Oakville, Iowa. Due to a levee breaching along the Iowa River during the US ...

  8. Flood risk assessment through 1D/2D couple HEC-RAS hydrodynamic modeling- A case study of Surat City, Lower Tapi Basin, India

    Science.gov (United States)

    Patel, Dhruvesh; Ramirez, Jorge; Srivastava, Prashant; Bray, Michaela; Han, Dawei

    2017-04-01

    Surat, known as the diamond city of Gujart is situated 100 km downstream of Ukai dam and near the mouth of river Tapi and affected by the flood at every alternate year. The city experienced catastrophic floods in 1933, 1959, 1968, 1970, 1994, 1998 and 2006. It is estimated that a single flood event during August 6-12, 2006 in Surat and Hazira twin-city, caused heavy damages, resulted in the death of 300 people and property damage worth € 289 million. The peak discharge of 25768 m3 s-1 release from Ukai dam was responsible for the disastrous flood in Surat city. To identifylow lying areas prone to inundation and reduce the uncertainty in flood mitigation measures, HEC-RAS based 1D/2D Couple hydrodynamic modeling is carried out for Surat city. Release from the Ukai dam and tidal level of the sea are considered for upstream and downstream boundary condition. 299 surveyed cross-sections have been considered for 1D modeling, whereas a topographic map at 0.5 m contour interval was used to produce a 5 m grid and SRTM (30 & 90 m) grid has been considered for Suart and Lower Tapi Basin (LTB). Flow is simulated under unsteady conditions, calibrated for the year 1998 and validated for the year 2006. The simulated result shows that the 9th August 18.00 hr was the worst day for Surat city and maximum 75-77 % area was under inundation. Most of the flooded area experienced 0.25 m/s water velocity with the duration of 90 hr. Due to low velocity and high duration of the flood, a low lying area within the west zone and south-west zone of the city was badly affected by the flood, whereas the south zone and south-east zone was least. Simulated results show good correlation when compared with an observed flood level map. The simulated results will be helpful to improve the flood resilience strategy at Surat city and reduce the uncertainty for flood inundation mapping for future dam releases. The present case study shows the applicability of 1D/2D coupled hydrodynamic modeling for

  9. Protecting Coastal Areas from Flooding by Injecting Solids into the Subsurface

    Science.gov (United States)

    Germanovich, L. N.; Murdoch, L.

    2008-12-01

    Subsidence and sea level rise conspire to increase the risk of flooding in coastal cities throughout the world, and these processes were key contributors to the devastation of New Orleans by hurricane Katrina. Constructing levees and placing fill to raise ground elevations are currently the main options for reducing flooding risks in coastal areas, and both of these options have drawbacks. We suggest that hydromechanical injection of solid compounds suspended in liquid can be used to lift the ground surface and thereby expand the options for protecting such coastal cities as New Orleans, Venice, and Shanghai from flooding. These techniques are broadly related to hydraulic fracturing and compensation grouting, where solid compounds are injected as slurries and cause upward displacements at the ground surface. The equipment and logistics required for hydromechanical solid injection and ground lifting are readily available from current geotechnical and petroleum operations. Hydraulic fractures are routinely created in the upper tens of meters of sediments, where they are filled with a wide range of different proppants for environmental applications. At shallow depths, many of these fractures are sub-parallel to the ground surface and lift their overburden by a few mm to cm, although lifting is not the objective of these fractures. Much larger, vertical displacements, of the order of several meters, could be created in low-cohesion sediments over areas as large as square kilometers. This would be achieved as a result of multiple injections. Injecting solid particulates provides the benefits of a permanent displacement supported by the solids. We have demonstrated that hydraulic fractures will lift the ground surface at shallow depths in Texas near the Sabine River, where the geological setting is generally similar to that of New Orleans (and where, incidentally, hurricane Rita landed in 2005). In these regions, the soft surficial sediments are underlain by relatively

  10. Characterization of peak streamflows and flood inundation at selected areas in North Carolina following Hurricane Matthew, October 2016

    Science.gov (United States)

    Musser, Jonathan W.; Watson, Kara M.; Gotvald, Anthony J.

    2017-05-05

    The passage of Hurricane Matthew through central and eastern North Carolina during October 7–9, 2016, brought heavy rainfall, which resulted in major flooding. More than 15 inches of rain was recorded in some areas. More than 600 roads were closed, including Interstates 95 and 40, and nearly 99,000 structures were affected by floodwaters. Immediately following the flooding, the U.S. Geological Survey documented 267 high-water marks, of which 254 were surveyed. North Carolina Emergency Management documented and surveyed 353 high-water marks. Using a subset of these highwater marks, six flood-inundation maps were created for hard-hit communities. Digital datasets of the inundation areas, study reach boundary, and water-depth rasters are available for download. In addition, peak gage-height data, peak streamflow data, and annual exceedance probabilities (in percent) were determined for 24 U.S. Geological Survey streamgages located near the heavily flooded communities.

  11. Insights from Guideline for Performance of Internal Flooding Probabilistic Risk Assessment (IFPRA)

    International Nuclear Information System (INIS)

    Choi, Sun Yeong; Yang, Joo Eon

    2009-01-01

    An internal flooding (IF) risk assessment refers to the quantitative probabilistic safety assessment (PSA) treatment of flooding as a result of pipe and tank breaks inside the plants, as well as from other recognized flood sources. The industry consensus standard for Internal Events Probabilistic Risk Assessment (ASME-RA-Sb-2005) includes high-level and supporting technical requirements for developing internal flooding probabilistic risk assessment (IFPRA). This industry standard is endorsed in Regulatory Guide 1.200, Revision 1 as an acceptable approach for addressing the risk contribution from IF events for risk informed applications that require U.S. Nuclear Regulatory commission (NRC) approval. In 2006, EPRI published a draft report for IFPRA that addresses the requirements of the ASME PRA consensus standard and have made efforts to refine and update the final EPRI IFPRA guideline. Westinghouse has performed an IFPRA analysis for several nuclear power plants (NPPs), such as Watts Bar and Fort Calhoun, using the draft EPRI guidelines for development of an IFPRA. Proprietary methodologies have been developed to apply the EPRI guidelines. The objectives of the draft report for IFPRA guideline are to: · Provide guidance for PSA practitioners in the performance of the elements of a PRA associated with internal flooding events consistent with the current state of the art for internal flooding PRA · Provide guidance regarding acceptable approaches that is sufficient to meeting the requirements of the ASME PRA Standard associated with internal flooding · Incorporate lessons learned in the performance of internal flooding PRAs including those identified as pilot applications of earlier drafts of this procedures guide The purpose of this paper is to present a vision for domestic nuclear power plants' IFPRA by comparing the method of the draft EPRI guidelines with the existing IFPRA method for domestic NPPs

  12. Insights from Guideline for Performance of Internal Flooding Probabilistic Risk Assessment (IFPRA)

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Sun Yeong; Yang, Joo Eon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2009-10-15

    An internal flooding (IF) risk assessment refers to the quantitative probabilistic safety assessment (PSA) treatment of flooding as a result of pipe and tank breaks inside the plants, as well as from other recognized flood sources. The industry consensus standard for Internal Events Probabilistic Risk Assessment (ASME-RA-Sb-2005) includes high-level and supporting technical requirements for developing internal flooding probabilistic risk assessment (IFPRA). This industry standard is endorsed in Regulatory Guide 1.200, Revision 1 as an acceptable approach for addressing the risk contribution from IF events for risk informed applications that require U.S. Nuclear Regulatory commission (NRC) approval. In 2006, EPRI published a draft report for IFPRA that addresses the requirements of the ASME PRA consensus standard and have made efforts to refine and update the final EPRI IFPRA guideline. Westinghouse has performed an IFPRA analysis for several nuclear power plants (NPPs), such as Watts Bar and Fort Calhoun, using the draft EPRI guidelines for development of an IFPRA. Proprietary methodologies have been developed to apply the EPRI guidelines. The objectives of the draft report for IFPRA guideline are to: {center_dot} Provide guidance for PSA practitioners in the performance of the elements of a PRA associated with internal flooding events consistent with the current state of the art for internal flooding PRA {center_dot} Provide guidance regarding acceptable approaches that is sufficient to meeting the requirements of the ASME PRA Standard associated with internal flooding {center_dot} Incorporate lessons learned in the performance of internal flooding PRAs including those identified as pilot applications of earlier drafts of this procedures guide The purpose of this paper is to present a vision for domestic nuclear power plants' IFPRA by comparing the method of the draft EPRI guidelines with the existing IFPRA method for domestic NPPs.

  13. RAPID Assessment of Extreme Reservoir Sedimentation Resulting from the September 2013 Flood, North St. Vrain Creek, CO

    Science.gov (United States)

    Rathburn, S. L.; McElroy, B. J.; Wohl, E.; Sutfin, N. A.; Huson, K.

    2014-12-01

    During mid-September 2013, approximately 360 mm of precipitation fell in the headwaters of the North St. Vrain drainage basin, Front Range, CO. Debris flows on steep hillslopes and extensive flooding along North St. Vrain Creek resulted in extreme sedimentation within Ralph Price Reservoir, municipal water supply for the City of Longmont. The event allows comparison of historical sedimentation with that of an unusually large flood because 1) no reservoir flushing has been conducted since dam construction, 2) reservoir stratigraphy chronicles uninterrupted delta deposition, and 3) this is the only on-channel reservoir with unimpeded, natural sediment flux from the Continental Divide to the mountain front in a basin with no significant historic flow modifications and land use impacts. Assessing the flood-related sedimentation prior to any dredging activities included coring the reservoir delta, a bathymetric survey of the delta, resistivity and ground penetrating radar surveys of the subaerial inlet deposit, and surveying tributary deposits. Over the 44-year life of the reservoir, two-thirds of the delta sedimentation is attributed to extreme discharges from the September 2013 storm. Total storm-derived reservoir sedimentation is approximately 275,000 m3, with 81% of that within the gravel-dominated inlet and 17% in the delta. Volumes of deposition within reservoir tributary inlets is negatively correlated with contributing area, possibly due to a lack of storage in these small basins (1-5 km2). Flood-related reservoir sedimentation will be compared to other research quantifying volumes from slope failures evident on post-storm lidar. Analysis of delta core samples will quantify organic carbon flux associated with the extreme discharge and develop a chronology of flood and fire disturbances for North St. Vrain basin. Applications of similar techniques are planned for two older Front Range reservoirs affected by the September flooding to fill knowledge gaps about

  14. Performance of Models for Flash Flood Warning and Hazard Assessment: The 2015 Kali Gandaki Landslide Dam Breach in Nepal

    Directory of Open Access Journals (Sweden)

    Jeremy D. Bricker

    2017-02-01

    Full Text Available The 2015 magnitude 7.8 Gorkha earthquake and its aftershocks weakened mountain slopes in Nepal. Co- and postseismic landsliding and the formation of landslide-dammed lakes along steeply dissected valleys were widespread, among them a landslide that dammed the Kali Gandaki River. Overtopping of the landslide dam resulted in a flash flood downstream, though casualties were prevented because of timely evacuation of low-lying areas. We hindcast the flood using the BREACH physically based dam-break model for upstream hydrograph generation, and compared the resulting maximum flow rate with those resulting from various empirical formulas and a simplified hydrograph based on published observations. Subsequent modeling of downstream flood propagation was compromised by a coarse-resolution digital elevation model with several artifacts. Thus, we used a digital-elevation-model preprocessing technique that combined carving and smoothing to derive topographic data. We then applied the 1-dimensional HEC-RAS model for downstream flood routing, and compared it to the 2-dimensional Delft-FLOW model. Simulations were validated using rectified frames of a video recorded by a resident during the flood in the village of Beni, allowing estimation of maximum flow depth and speed. Results show that hydrological smoothing is necessary when using coarse topographic data (such as SRTM or ASTER, as using raw topography underestimates flow depth and speed and overestimates flood wave arrival lag time. Results also show that the 2-dimensional model produces more accurate results than the 1-dimensional model but the 1-dimensional model generates a more conservative result and can be run in a much shorter time. Therefore, a 2-dimensional model is recommended for hazard assessment and planning, whereas a 1-dimensional model would facilitate real-time warning declaration.

  15. Assessment of the health impacts of the 2011 summer floods in Brisbane.

    Science.gov (United States)

    Alderman, Katarzyna; Turner, Lyle R; Tong, Shilu

    2013-08-01

    To assess the effects of the 2011 floods in Brisbane, Australia, on residents' physical and mental health. Residents who had been affected by the floods completed a community-based survey that examined the direct impact of flooding on households and their perceived physical and mental health. Outcome variables included overall and respiratory health and mental health outcomes related to psychological distress, sleep quality, and posttraumatic stress disorder (PTSD). Multivariable logistic regression was used to examine the association between flooding and perceived health outcome variables, adjusted for current health status and sociodemographic factors. Residents whose households were directly affected by flooding were more likely to report poor overall (Odds Ratio [OR] 5.3; 95% CI, 2.8-10.1) and respiratory (OR 2.3; 95% CI, 1.1-4.6) health, psychological distress (OR 1.9; 95% CI, 1.1-3.5), poor sleep quality (OR 2.3; 95% CI, 1.2-4.4), and probable PTSD (OR 2.3; 95% CI, 1.2-4.5). The 2011 Brisbane floods had significant impact on the physical and psychosocial health of residents. Improved support strategies may need to be integrated into existing disaster management programs to reduce flood-related health impacts, particularly those related to mental health.

  16. 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.

  17. Assessment of homogeneity of regions for regional flood frequency analysis

    Science.gov (United States)

    Lee, Jeong Eun; Kim, Nam Won

    2016-04-01

    This paper analyzed the effect of rainfall on hydrological similarity, which is an important step for regional flood frequency analysis (RFFA). For the RFFA, storage function method (SFM) using spatial extension technique was applied for the 22 sub-catchments that are partitioned from Chungju dam watershed in Republic of Korea. We used the SFM to generate the annual maximum floods for 22 sub-catchments using annual maximum storm events (1986~2010) as input data. Then the quantiles of rainfall and flood were estimated using the annual maximum series for the 22 sub-catchments. Finally, spatial variations in terms of two quantiles were analyzed. As a result, there were significant correlation between spatial variations of the two quantiles. This result demonstrates that spatial variation of rainfall is an important factor to explain the homogeneity of regions when applying RFFA. Acknowledgements: This research was supported by a grant (11-TI-C06) from Advanced Water Management Research Program funded by Ministry of Land, Infrastructure and Transport of Korean government.

  18. Automating Flood Hazard Mapping Methods for Near Real-time Storm Surge Inundation and Vulnerability Assessment

    Science.gov (United States)

    Weigel, A. M.; Griffin, R.; Gallagher, D.

    2015-12-01

    Storm surge has enough destructive power to damage buildings and infrastructure, erode beaches, and threaten human life across large geographic areas, hence posing the greatest threat of all the hurricane hazards. The United States Gulf of Mexico has proven vulnerable to hurricanes as it has been hit by some of the most destructive hurricanes on record. With projected rises in sea level and increases in hurricane activity, there is a need to better understand the associated risks for disaster mitigation, preparedness, and response. GIS has become a critical tool in enhancing disaster planning, risk assessment, and emergency response by communicating spatial information through a multi-layer approach. However, there is a need for a near real-time method of identifying areas with a high risk of being impacted by storm surge. Research was conducted alongside Baron, a private industry weather enterprise, to facilitate automated modeling and visualization of storm surge inundation and vulnerability on a near real-time basis. This research successfully automated current flood hazard mapping techniques using a GIS framework written in a Python programming environment, and displayed resulting data through an Application Program Interface (API). Data used for this methodology included high resolution topography, NOAA Probabilistic Surge model outputs parsed from Rich Site Summary (RSS) feeds, and the NOAA Census tract level Social Vulnerability Index (SoVI). The development process required extensive data processing and management to provide high resolution visualizations of potential flooding and population vulnerability in a timely manner. The accuracy of the developed methodology was assessed using Hurricane Isaac as a case study, which through a USGS and NOAA partnership, contained ample data for statistical analysis. This research successfully created a fully automated, near real-time method for mapping high resolution storm surge inundation and vulnerability for the

  19. Assessing uncertainties in flood forecasts for decision making: prototype of an operational flood management system integrating ensemble predictions

    Directory of Open Access Journals (Sweden)

    J. Dietrich

    2009-08-01

    Full Text Available Ensemble forecasts aim at framing the uncertainties of the potential future development of the hydro-meteorological situation. A probabilistic evaluation can be used to communicate forecast uncertainty to decision makers. Here an operational system for ensemble based flood forecasting is presented, which combines forecasts from the European COSMO-LEPS, SRNWP-PEPS and COSMO-DE prediction systems. A multi-model lagged average super-ensemble is generated by recombining members from different runs of these meteorological forecast systems. A subset of the super-ensemble is selected based on a priori model weights, which are obtained from ensemble calibration. Flood forecasts are simulated by the conceptual rainfall-runoff-model ArcEGMO. Parameter uncertainty of the model is represented by a parameter ensemble, which is a priori generated from a comprehensive uncertainty analysis during model calibration. The use of a computationally efficient hydrological model within a flood management system allows us to compute the hydro-meteorological model chain for all members of the sub-ensemble. The model chain is not re-computed before new ensemble forecasts are available, but the probabilistic assessment of the output is updated when new information from deterministic short range forecasts or from assimilation of measured data becomes available. For hydraulic modelling, with the desired result of a probabilistic inundation map with high spatial resolution, a replacement model can help to overcome computational limitations. A prototype of the developed framework has been applied for a case study in the Mulde river basin. However these techniques, in particular the probabilistic assessment and the derivation of decision rules are still in their infancy. Further research is necessary and promising.

  20. Geodiversity assessment in urban areas

    Science.gov (United States)

    Ilic, Marina; Stojković, Sanja; Rundić, Ljupko; Ćalić, Jelena; Sandić, Dejan

    2017-04-01

    Conflict over natural resources figured prominently in the urban areas. On the one hand there is a constant need for space for the construction of new buildings for housing, agriculture and industrial production, and on the other hand the resources need protection because of the threat of degradation or even complete destruction. Considering the fact that urbanization is one of the most serious threats to geodiversity, it is important that this issue is taken into account in spatial development plans and georesource management strategies in urban areas. The geodiversity, as well as natural resource, must be managed in a sustainable manner in which it is very important its protection. The mapping of specific categories of geodiversity (geological, geomorphological, hydrological and soil) on the basis of quantitative assessment with the use of Geographic Information Systems (GIS) can allow spatial planners and managers to take further steps that would reduce threats and protect the natural values. This work presents the application of geodiversity evaluation method by using the geodiversity index (Gd), based on the quantity of abiotic elements and relief roughness within a spatial unit in the case of the City of Belgrade, Serbia. The acquired results are analyzed in the context of sustainable use of georesources and the threats to which geodiversity is exposed due to the development of the city.

  1. Review Article: A comparison of flood and earthquake vulnerability assessment indicators

    Science.gov (United States)

    de Ruiter, Marleen C.; Ward, Philip J.; Daniell, James E.; Aerts, Jeroen C. J. H.

    2017-07-01

    In a cross-disciplinary study, we carried out an extensive literature review to increase understanding of vulnerability indicators used in the disciplines of earthquake- and flood vulnerability assessments. We provide insights into potential improvements in both fields by identifying and comparing quantitative vulnerability indicators grouped into physical and social categories. Next, a selection of index- and curve-based vulnerability models that use these indicators are described, comparing several characteristics such as temporal and spatial aspects. Earthquake vulnerability methods traditionally have a strong focus on object-based physical attributes used in vulnerability curve-based models, while flood vulnerability studies focus more on indicators applied to aggregated land-use classes in curve-based models. In assessing the differences and similarities between indicators used in earthquake and flood vulnerability models, we only include models that separately assess either of the two hazard types. Flood vulnerability studies could be improved using approaches from earthquake studies, such as developing object-based physical vulnerability curve assessments and incorporating time-of-the-day-based building occupation patterns. Likewise, earthquake assessments could learn from flood studies by refining their selection of social vulnerability indicators. Based on the lessons obtained in this study, we recommend future studies for exploring risk assessment methodologies across different hazard types.

  2. Development of a Probabilistic Flood Hazard Assessment (PFHA) for the nuclear safety

    Science.gov (United States)

    Ben Daoued, Amine; Guimier, Laurent; Hamdi, Yasser; Duluc, Claire-Marie; Rebour, Vincent

    2016-04-01

    The purpose of this study is to lay the basis for a probabilistic evaluation of flood hazard (PFHA). Probabilistic assessment of external floods has become a current topic of interest to the nuclear scientific community. Probabilistic approaches complement deterministic approaches by exploring a set of scenarios and associating a probability to each of them. These approaches aim to identify all possible failure scenarios, combining their probability, in order to cover all possible sources of risk. They are based on the distributions of initiators and/or the variables caracterizing these initiators. The PFHA can characterize the water level for example at defined point of interest in the nuclear site. This probabilistic flood hazard characterization takes into account all the phenomena that can contribute to the flooding of the site. The main steps of the PFHA are: i) identification of flooding phenomena (rains, sea water level, etc.) and screening of relevant phenomena to the nuclear site, ii) identification and probabilization of parameters associated to selected flooding phenomena, iii) spreading of the probabilized parameters from the source to the point of interest in the site, v) obtaining hazard curves and aggregation of flooding phenomena contributions at the point of interest taking into account the uncertainties. Within this framework, the methodology of the PFHA has been developed for several flooding phenomena (rain and/or sea water level, etc.) and then implemented and tested with a simplified case study. In the same logic, our study is still in progress to take into account other flooding phenomena and to carry out more case studies.

  3. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, Northampton County, Virginia (And Incorporated Areas)

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  4. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, JACKSON COUNTY, TEXAS (AND INCORPORATED AREAS)

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  5. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, ALBANY COUNTY, WYOMING (AND INCORPORATED AREAS)

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  6. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, MOHAVE COUNTY, ARIZONA (AND INCORPORATED AREAS)

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  7. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, NAVARRO COUNTY, TEXAS (AND INCORPORATED AREAS)

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  8. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, McCURTAIN COUNTY, OKLAHOMA AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  9. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, KENDALL COUNTY AND INCORPORATED AREAS, TEXAS, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  10. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, DALE COUNTY, ALABAMA AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  11. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, SEVIER COUNTY, TENNESSEE (AND INCORPORATED AREAS)

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  12. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, GRAINGER COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  13. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, TAYLOR COUNTY, TX AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  14. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, CHURCHILL COUNTY, NEVADA (AND INCORPORATED AREAS)

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  15. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, COMAL COUNTY AND INCORPORATED AREAS, TEXAS, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  16. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, FORSYTH COUNTY, GEORGIA, AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk Information And supporting data used to develop the risk data. The primary risk;...

  17. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, ARLINGTON COUNTY, VA, USA, AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  18. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, CAPE GIRARDEAU COUNTY, MISSOURI (AND INCORPORATED AREAS)

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  19. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, Otero COUNTY and Incorporated Areas, NEW MEXICO, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  20. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, Lee County, Alabama and Incorporated Areas

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  1. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, CLARKE COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  2. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, JONES COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  3. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, CHESTER COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  4. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, MCNAIRY COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  5. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, SUMNER COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  6. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, MEIGS COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  7. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, LEWIS COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  8. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, JACKSON COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  9. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, SEQUATCHIE COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  10. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, PICKETT COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  11. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, WEAKLEY COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  12. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, MARION COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  13. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, DYER COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  14. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, UNICOI COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  15. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, HANCOCK COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  16. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, RHEA COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  17. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, PERRY COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  18. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, ORANGE COUNTY, FLORIDA AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  19. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, BREVARD COUNTY, FLORIDA AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  20. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, CANYON COUNTY, IDAHO (AND INCORPORATED AREAS)

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  1. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, PICKENS COUNTY, SOUTH CAROLINA AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  2. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, EAST BATON ROUGE PARISH, LOUISIANA (AND INCORPORATED AREAS)

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  3. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, RICHLAND COUNTY, SOUTH CAROLINA AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  4. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, LEWIS COUNTY, WEST VIRGINIA (AND INCORPORATED AREAS)

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  5. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, CANNON COUNTY,TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  6. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, CITY AND COUNTY OF CUSTER COUNTY, MONTANA (AND INCORPORATED AREAS)

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  7. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, MCMINN COUNTY, TENNESSEE (AND INCORPORATED AREAS)

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  8. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, LAVACA COUNTY, TEXAS (AND INCORPORATED AREAS)

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  9. Digital Flood Insurance Rate Map Database for Hot Spring County (and Incorporated Areas), AR, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  10. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, OCONEE COUNTY, SOUTH CAROLINA AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  11. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, RANKIN COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  12. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, CITRUS COUNTY, FLORIDA AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  13. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, LAKE COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  14. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, MADISON COUNTY AND INCORPORATED AREAS, MO, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  15. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, SMITH COUNTY, TEXAS, USA and Incorporated Areas

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  16. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, CALHOUN COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  17. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, LEWIS COUNTY AND INCORPORATED AREAS, MO, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  18. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, HARRISON COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  19. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, POWESHIEK COUNTY, IOWA AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  20. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, WARREN COUNTY AND INCORPORATED AREAS, IA, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  1. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, HANCOCK COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  2. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, LA PAZ COUNTY, ARIZONA AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  3. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, BENTON COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  4. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, MUSKOGEE COUNTY, OKLAHOMA AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  5. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, CHESTER COUNTY AND INCORPORATED AREAS, SOUTH CAROLINA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  6. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, ATKINSON COUNTY, GEORGIA AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  7. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, COFFEE COUNTY, ALABAMA AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  8. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, COFFEE COUNTY, GEORGIA AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  9. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, ST. LUCIE COUNTY, FLORIDA AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  10. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, CLAIBORNE COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  11. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, VOLUSIA COUNTY, FLORIDA AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  12. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, MARENGO COUNTY, ALABAMA AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  13. DIGITAL FLOOD INSURANCE RATE MAP, SWEET GRASS COUNTY, MONTANA (AND INCORPORATED AREAS)

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  14. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, JEFFERSON COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  15. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, STONE COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  16. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, DARKE COUNTY, OHIO (AND INCORPORATED AREAS)

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  17. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, TUNICA COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  18. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, CLAY COUNTY, FLORIDA AND INCORPORATED AREAS

    Data.gov (United States)

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  19. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, LAFAYETTE COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

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  20. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, CROCKETT COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

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  1. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, TIPPAH COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

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  2. DIGITAL FLOOD INSURANCE RATE MAP, FLATHEAD COUNTY, MONTANA (AND INCORPORATED AREAS)

    Data.gov (United States)

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  3. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, DENTON COUNTY, TEXAS AND INCORPORATED AREAS)

    Data.gov (United States)

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  4. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, CRAWFORD COUNTY, OHIO (AND INCORPORATED AREAS)

    Data.gov (United States)

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  5. DIGITAL FLOOD INSURANCE RATE MAP, SMYTH COUNTY, VIRGINIA (AND INCORPORATED AREAS)

    Data.gov (United States)

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  6. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, PORTAGE COUNTY, WISCONSIN (AND INCORPORATED AREAS)

    Data.gov (United States)

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  7. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, JACKSON COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

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  8. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, CROSS COUNTY, ARKANSAS, AND INCORPORATED AREAS

    Data.gov (United States)

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  9. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, ASHLEY COUNTY, ARKANSAS (AND INCORPORATED AREAS)

    Data.gov (United States)

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  10. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, KERN COUNTY, CALIFORNIA (AND INCORPORATED AREAS)

    Data.gov (United States)

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  11. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, LE FLORE COUNTY, OKLAHOMA AND INCORPORATED AREAS

    Data.gov (United States)

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  12. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, COOK COUNTY, GEORGIA AND INCORPORATED AREAS

    Data.gov (United States)

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  13. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, TAYLOR COUNTY, WEST VIRGINIA (AND INCORPORATED AREAS)

    Data.gov (United States)

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  14. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, SEMINOLE COUNTY, GEORGIA AND INCORPORATED AREAS

    Data.gov (United States)

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  15. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, LAWRENCE COUNTY, TENNESSEE and INCORPORATED AREAS

    Data.gov (United States)

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  16. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, TUSCALOOSA COUNTY, ALABAMA AND INCORPORATED AREAS

    Data.gov (United States)

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  17. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, COBB COUNTY, GEORGIA, AND INCORPORATED AREAS

    Data.gov (United States)

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  18. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, JASPER COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

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  19. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, SEMINOLE COUNTY, FLORIDA AND INCORPORATED AREAS

    Data.gov (United States)

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  20. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, MARSHALL COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

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  1. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, COPIAH COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

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  2. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, UNION COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

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  3. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, GRUNDY COUNTY, TENNESSEE and INCORPORATED AREAS

    Data.gov (United States)

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  4. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, WINSTON COUNTY, ALABAMA AND INCORPORATED AREAS

    Data.gov (United States)

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  5. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, CEDAR COUNTY AND INCORPORATED AREAS, MO, USA

    Data.gov (United States)

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  6. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, Colquitt COUNTY, GEORGIA AND INCORPORATED AREAS

    Data.gov (United States)

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  7. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, COFFEE COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

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  8. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, SUNFLOWER COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

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  9. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, FAIRFAX COUNTY, VIRGINIA (AND INCORPORATED AREAS)

    Data.gov (United States)

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  10. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, SALT LAKE COUNTY AND INCORPORATED AREAS, SALT LAKE COUNTY, UTAH

    Data.gov (United States)

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  11. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, YORK COUNTY, SOUTH CAROLINA AND INCORPORATED AREAS

    Data.gov (United States)

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  12. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, WASHITA COUNTY, OKLAHOMA, USA and Incorporated Areas

    Data.gov (United States)

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  13. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, PIERCE COUNTY, WISCONSIN (AND INCORPORATED AREAS)

    Data.gov (United States)

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  14. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, SMITH COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

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  15. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, RUTHERFORD COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

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  16. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, CHICKASAW COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

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  17. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, MADISON COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

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  18. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, LEAKE COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

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  19. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, GWINNETT COUNTY, GEORGIA, AND INCORPORATED AREAS

    Data.gov (United States)

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  20. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, WARE COUNTY, GEORGIA AND INCORPORATED AREAS

    Data.gov (United States)

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  1. DIGITAL FLOOD INSURANCE MAP DATABASE, COLUMBIA COUNTY, GEORGIA, AND INCORPORATED AREAS

    Data.gov (United States)

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  2. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, HENRY COUNTY, ALABAMA AND INCORPORATED AREAS

    Data.gov (United States)

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  3. DIGITAL FLOOD INSURANCE RATE MAP, CROOK COUNTY, OREGON (AND INCORPORATED AREAS)

    Data.gov (United States)

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  4. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, BLOUNT COUNTY, ALABAMA AND INCORPORATED AREAS

    Data.gov (United States)

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  5. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, SCOTT COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  6. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, OBION COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

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  7. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, CARTER COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

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  8. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, STORY COUNTY AND INCORPORATED AREAS, IA, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  9. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, HOLMES COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  10. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, BROWARD COUNTY, FLORIDA AND INCOROPORATED AREAS

    Data.gov (United States)

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  11. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, HILL COUNTY, TEXAS (AND INCORPORATED AREAS)

    Data.gov (United States)

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  12. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, ANNE ARUNDEL COUNTY, MARYLAND (AND INCORPORATED AREAS)

    Data.gov (United States)

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  13. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, TIPPECANOE COUNTY, INDIANA, AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  14. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, CECIL COUNTY, MARYLAND (AND INCORPORATED AREAS)

    Data.gov (United States)

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  15. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, WEBSTER COUNTY AND INCORPORATED AREAS, MO, USA

    Data.gov (United States)

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  16. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, TARRANT COUNTY, TEXAS (AND INCORPORATED AREAS)

    Data.gov (United States)

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  17. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, MILWAUKEE, WISCONSIN (AND INCORPORATED AREAS)

    Data.gov (United States)

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  18. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, MIAMI COUNTY, OHIO (AND INCORPORATED AREAS)

    Data.gov (United States)

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  19. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, ST. JOHN THE BAPTIST PARISH, LOUISIANA (AND INCORPORATED AREAS)

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  20. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, DUVAL COUNTY, FLORIDA (AND INCORPORATED AREAS)

    Data.gov (United States)

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  1. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, BARTHOLOMEW COUNTY, INDIANA (AND INCORPORATED AREAS)

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  2. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, MORGAN COUNTY, INDIANA (AND INCORPORATED AREAS)

    Data.gov (United States)

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  3. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, DALLAS COUNTY, TEXAS (AND INCORPORATED AREAS)

    Data.gov (United States)

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  4. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, SIMPSON COUNTY, MISSISSIPPI AND INCORPORATED AREAS

    Data.gov (United States)

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  5. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, PINELLAS COUNTY, FLORIDA AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  6. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, MACON COUNTY, TENNESSEE and INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  7. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, STEWART COUNTY (AND INCORPORATED AREAS)

    Data.gov (United States)

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  8. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, UNION COUNTY, SOUTH CAROLINA AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  9. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, CLAIBORNE COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  10. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, COCKE COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  11. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, FRANKLIN COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  12. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, JOHNSON COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  13. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, MAURY COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  14. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, MADISON COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  15. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, FAYETTE COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  16. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, HUMPHREYS COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  17. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, DECATUR COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  18. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, GIBSON COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  19. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, DICKSON COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  20. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, FENTRESS COUNTY, TENNESSEE AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...