WorldWideScience

Sample records for maximum flood pmf

  1. PMF (probable maximum flood) study for Nevada Nuclear Waste Storage Investigation Project

    International Nuclear Information System (INIS)

    Bullard, K.L.

    1986-01-01

    This document estimates the risk of flooding in the high-level radioactive waste depository proposed for the Yucca Mountain of Nevada. Described are the general features of the proposed site, the drainage pattern of the surrounding area, the historical pattern of precipitation, and an estimate of future precipitation trends. Information from this report will be used in decisions on flood protection construction at this facility. 10 refs., 61 figs., 42 tabs

  2. Review of the Probable Maximum Flood (PMF) Snowmelt Analysis for Success Dam

    Science.gov (United States)

    2015-11-01

    watershed; and the USACE reports (1998, 2013) further describe the watershed characteris- tics, vegetation , climate, precipitation, and flooding. The...developed SCA product, MOD10A1, the MODIS/ Terra Snow Cover Daily L3 Global 500 m Grid (Hall et al. 2006), which provides a daily estimate of the fSCA of...find mean cloud persistence, or the average time between cloud-free scenes, to be less than a day at Terra MODIS’s temporal scale (approxi- mately 1

  3. Probable maximum flood control

    International Nuclear Information System (INIS)

    DeGabriele, C.E.; Wu, C.L.

    1991-11-01

    This study proposes preliminary design concepts to protect the waste-handling facilities and all shaft and ramp entries to the underground from the probable maximum flood (PMF) in the current design configuration for the proposed Nevada Nuclear Waste Storage Investigation (NNWSI) repository protection provisions were furnished by the United States Bureau of Reclamation (USSR) or developed from USSR data. Proposed flood protection provisions include site grading, drainage channels, and diversion dikes. Figures are provided to show these proposed flood protection provisions at each area investigated. These areas are the central surface facilities (including the waste-handling building and waste treatment building), tuff ramp portal, waste ramp portal, men-and-materials shaft, emplacement exhaust shaft, and exploratory shafts facility

  4. Probable maximum flood on the Ha Ha River

    International Nuclear Information System (INIS)

    Damov, D.; Masse, B.

    1997-01-01

    Results of a probable maximum flood (PMF) study conducted for various locations along the Ha Ha river, a tributary of the Saguenay River, were discussed. The study was undertaken for use in the design and construction of new hydraulic structures for water supply for a pulp and paper facility, following the Saguenay Flood in July 1996. Many different flood scenarios were considered, including combinations of snow-melt with rainfall. Using computer simulations, it was shown that the largest flood flows were generated by summer-fall PMF. 5 refs., 12 figs

  5. Paddle River Dam : review of probable maximum flood

    Energy Technology Data Exchange (ETDEWEB)

    Clark, D. [UMA Engineering Ltd., Edmonton, AB (Canada); Neill, C.R. [Northwest Hydraulic Consultants Ltd., Edmonton, AB (Canada)

    2008-07-01

    The Paddle River Dam was built in northern Alberta in the mid 1980s for flood control. According to the 1999 Canadian Dam Association (CDA) guidelines, this 35 metre high, zoned earthfill dam with a spillway capacity sized to accommodate a probable maximum flood (PMF) is rated as a very high hazard. At the time of design, it was estimated to have a peak flow rate of 858 centimetres. A review of the PMF in 2002 increased the peak flow rate to 1,890 centimetres. In light of a 2007 revision of the CDA safety guidelines, the PMF was reviewed and the inflow design flood (IDF) was re-evaluated. This paper discussed the levels of uncertainty inherent in PMF determinations and some difficulties encountered with the SSARR hydrologic model and the HEC-RAS hydraulic model in unsteady mode. The paper also presented and discussed the analysis used to determine incremental damages, upon which a new IDF of 840 m{sup 3}/s was recommended. The paper discussed the PMF review, modelling methodology, hydrograph inputs, and incremental damage of floods. It was concluded that the PMF review, involving hydraulic routing through the valley bottom together with reconsideration of the previous runoff modeling provides evidence that the peak reservoir inflow could reasonably be reduced by approximately 20 per cent. 8 refs., 5 tabs., 8 figs.

  6. Probable maximum flood analysis, Richton Dome, Mississippi-Phase I: Technical report

    International Nuclear Information System (INIS)

    1987-03-01

    This report presents results of a preliminary analysis of the extent of inundation that would result from a probable maximum flood (PMF) event in the overdome area of Richton Dome, Mississippi. Bogue Homo and Thompson Creek watersheds drain the overdome area. The US Army Corps of Engineers' HEC-1 Flood Hydrograph Package was used to calculate runoff hydrographs, route computed flood hydrographs, and determine maximum flood stages at cross sections along overdome tributaries. The area and configuration of stream cross sections were determined from US Geological Survey topographic maps. Using maximum flood stages calculated by the HEC-1 analysis, areas of inundation were delineated on 10-ft (3-m) contour interval topographic maps. Approximately 10% of the overdome area, or 0.9 mi 2 (2 km 2 ), would be inundated by a PMF event. 34 refs., 3 figs., 1 tab

  7. Effects of variability in probable maximum precipitation patterns on flood losses

    Science.gov (United States)

    Zischg, Andreas Paul; Felder, Guido; Weingartner, Rolf; Quinn, Niall; Coxon, Gemma; Neal, Jeffrey; Freer, Jim; Bates, Paul

    2018-05-01

    The assessment of the impacts of extreme floods is important for dealing with residual risk, particularly for critical infrastructure management and for insurance purposes. Thus, modelling of the probable maximum flood (PMF) from probable maximum precipitation (PMP) by coupling hydrological and hydraulic models has gained interest in recent years. Herein, we examine whether variability in precipitation patterns exceeds or is below selected uncertainty factors in flood loss estimation and if the flood losses within a river basin are related to the probable maximum discharge at the basin outlet. We developed a model experiment with an ensemble of probable maximum precipitation scenarios created by Monte Carlo simulations. For each rainfall pattern, we computed the flood losses with a model chain and benchmarked the effects of variability in rainfall distribution with other model uncertainties. The results show that flood losses vary considerably within the river basin and depend on the timing and superimposition of the flood peaks from the basin's sub-catchments. In addition to the flood hazard component, the other components of flood risk, exposure, and vulnerability contribute remarkably to the overall variability. This leads to the conclusion that the estimation of the probable maximum expectable flood losses in a river basin should not be based exclusively on the PMF. Consequently, the basin-specific sensitivities to different precipitation patterns and the spatial organization of the settlements within the river basin need to be considered in the analyses of probable maximum flood losses.

  8. The effect of coupling hydrologic and hydrodynamic models on probable maximum flood estimation

    Science.gov (United States)

    Felder, Guido; Zischg, Andreas; Weingartner, Rolf

    2017-07-01

    Deterministic rainfall-runoff modelling usually assumes stationary hydrological system, as model parameters are calibrated with and therefore dependant on observed data. However, runoff processes are probably not stationary in the case of a probable maximum flood (PMF) where discharge greatly exceeds observed flood peaks. Developing hydrodynamic models and using them to build coupled hydrologic-hydrodynamic models can potentially improve the plausibility of PMF estimations. This study aims to assess the potential benefits and constraints of coupled modelling compared to standard deterministic hydrologic modelling when it comes to PMF estimation. The two modelling approaches are applied using a set of 100 spatio-temporal probable maximum precipitation (PMP) distribution scenarios. The resulting hydrographs, the resulting peak discharges as well as the reliability and the plausibility of the estimates are evaluated. The discussion of the results shows that coupling hydrologic and hydrodynamic models substantially improves the physical plausibility of PMF modelling, although both modelling approaches lead to PMF estimations for the catchment outlet that fall within a similar range. Using a coupled model is particularly suggested in cases where considerable flood-prone areas are situated within a catchment.

  9. Review of probable maximum flood definition at B.C. Hydro

    International Nuclear Information System (INIS)

    Keenhan, P.T.; Kroeker, M.G.; Neudorf, P.A.

    1991-01-01

    Probable maximum floods (PMF) have been derived for British Columbia Hydro structures since design of the W.C. Bennet Dam in 1965. A dam safety program for estimating PMF for structures designed before that time has been ongoing since 1979. The program, which has resulted in rehabilitative measures at dams not meeting current established standards, is now being directed at the more recently constructed larger structures on the Peace and Columbia rivers. Since 1965 detailed studies have produced 23 probable maximum precipitation (PMP) and 24 PMF estimates. What defines a PMF in British Columbia in terms of an appropriate combination of meteorological conditions varies due to basin size and the climatic effect of mountain barriers. PMP is estimated using three methods: storm maximization and transposition, orographic separation method, and modification of non-orographic PMP for orography. Details of, and problems encountered with, these methods are discussed. Tools or methods to assess meterological limits for antecedant conditions and for limits to runoff during extreme events have not been developed and require research effort. 11 refs., 2 figs., 3 tabs

  10. 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)

  11. Revision of regional maximum flood (RMF) estimation in Namibia ...

    African Journals Online (AJOL)

    Extreme flood hydrology in Namibia for the past 30 years has largely been based on the South African Department of Water Affairs Technical Report 137 (TR 137) of 1988. This report proposes an empirically established upper limit of flood peaks for regions called the regional maximum flood (RMF), which could be ...

  12. Coupling Hydrologic and Hydrodynamic Models to Estimate PMF

    Science.gov (United States)

    Felder, G.; Weingartner, R.

    2015-12-01

    Most sophisticated probable maximum flood (PMF) estimations derive the PMF from the probable maximum precipitation (PMP) by applying deterministic hydrologic models calibrated with observed data. This method is based on the assumption that the hydrological system is stationary, meaning that the system behaviour during the calibration period or the calibration event is presumed to be the same as it is during the PMF. However, as soon as a catchment-specific threshold is reached, the system is no longer stationary. At or beyond this threshold, retention areas, new flow paths, and changing runoff processes can strongly affect downstream peak discharge. These effects can be accounted for by coupling hydrologic and hydrodynamic models, a technique that is particularly promising when the expected peak discharge may considerably exceed the observed maximum discharge. In such cases, the coupling of hydrologic and hydraulic models has the potential to significantly increase the physical plausibility of PMF estimations. This procedure ensures both that the estimated extreme peak discharge does not exceed the physical limit based on riverbed capacity and that the dampening effect of inundation processes on peak discharge is considered. Our study discusses the prospect of considering retention effects on PMF estimations by coupling hydrologic and hydrodynamic models. This method is tested by forcing PREVAH, a semi-distributed deterministic hydrological model, with randomly generated, physically plausible extreme precipitation patterns. The resulting hydrographs are then used to externally force the hydraulic model BASEMENT-ETH (riverbed in 1D, potential inundation areas in 2D). Finally, the PMF estimation results obtained using the coupled modelling approach are compared to the results obtained using ordinary hydrologic modelling.

  13. Nevada Test Site probable maximum flood study, part of US Geological Survey flood potential and debris hazard study, Yucca Mountain Site for US Department of Energy, Office of Civilian Radioactive Waste Management

    International Nuclear Information System (INIS)

    Bullard, K.L.

    1994-01-01

    The US Geological Survey (USGS), as part of the Yucca Mountain Project (YMP), is conducting studies at Yucca Mountain, Nevada. The purposes of these studies are to provide hydrologic and geologic information to evaluate the suitability of Yucca Mountain for development as a high-level nuclear waste repository, and to evaluate the ability of the mined geologic disposal system (MGDS) to isolate the waste in compliance with regulatory requirements. In particular, the project is designed to acquire information necessary for the Department of Energy (DOE) to demonstrate in its environmental impact statement (EIS) and license application whether the MGDS will meet the requirements of federal regulations 10 CFR Part 60, 10 CFR Part 960, and 40 CFR Part 191. Complete study plans for this part of the project were prepared by the USGS and approved by the DOE in August and September of 1990. The US Bureau of Reclamation (Reclamation) was selected by the USGS as a contractor to provide probable maximum flood (PMF) magnitudes and associated inundation maps for preliminary engineering design of the surface facilities at Yucca Mountain. These PMF peak flow estimates are necessary for successful waste repository design and construction. The PMF technique was chosen for two reasons: (1) this technique complies with ANSI requirements that PMF technology be used in the design of nuclear related facilities (ANSI/ANS, 1981), and (2) the PMF analysis has become a commonly used technology to predict a ''worst possible case'' flood scenario. For this PMF study, probable maximum precipitation (PMP) values were obtained for a local storm (thunderstorm) PMP event. These values were determined from the National Weather Services's Hydrometeorological Report No. 49 (HMR 49)

  14. MAXIMUM RUNOFF OF THE FLOOD ON WADIS OF NORTHERN ...

    African Journals Online (AJOL)

    lanez

    The technique of account the maximal runoff of flood for the rivers of northern part of Algeria based on the theory of ... north to south: 1) coastal Tel – fertile, high cultivated and sown zone; 2) territory of Atlas. Mountains ... In the first case the empiric dependence between maximum intensity of precipitation for some calculation ...

  15. Optimal Control of Polymer Flooding Based on Maximum Principle

    Directory of Open Access Journals (Sweden)

    Yang Lei

    2012-01-01

    Full Text Available Polymer flooding is one of the most important technologies for enhanced oil recovery (EOR. In this paper, an optimal control model of distributed parameter systems (DPSs for polymer injection strategies is established, which involves the performance index as maximum of the profit, the governing equations as the fluid flow equations of polymer flooding, and the inequality constraint as the polymer concentration limitation. To cope with the optimal control problem (OCP of this DPS, the necessary conditions for optimality are obtained through application of the calculus of variations and Pontryagin’s weak maximum principle. A gradient method is proposed for the computation of optimal injection strategies. The numerical results of an example illustrate the effectiveness of the proposed method.

  16. Revision of regional maximum flood (RMF) estimation in Namibia

    African Journals Online (AJOL)

    2013-11-26

    Nov 26, 2013 ... sediment deposits, also known as slackwater flood deposits, are stage indicators of ..... of these stations has been operational for 33 years. This cor- responds to ..... Management, University of Haifa, Haifa, Israel. GRODEK T ...

  17. A review of the regional maximum flood and rational formula using ...

    African Journals Online (AJOL)

    Flood estimation methods in South Africa are based on three general approaches: empirical, deterministic and probabilistic. The \\"quick\\" methods often used as checks are the regional maximum flood (RMF) and the rational formula (RF), which form part of the empirical and deterministic methods respectively. A database of ...

  18. Evaluating Annual Maximum and Partial Duration Series for Estimating Frequency of Small Magnitude Floods

    Directory of Open Access Journals (Sweden)

    Fazlul Karim

    2017-06-01

    Full Text Available Understanding the nature of frequent floods is important for characterising channel morphology, riparian and aquatic habitat, and informing river restoration efforts. This paper presents results from an analysis on frequency estimates of low magnitude floods using the annual maximum and partial series data compared to actual flood series. Five frequency distribution models were fitted to data from 24 gauging stations in the Great Barrier Reef (GBR lagoon catchments in north-eastern Australia. Based on the goodness of fit test, Generalised Extreme Value, Generalised Pareto and Log Pearson Type 3 models were used to estimate flood frequencies across the study region. Results suggest frequency estimates based on a partial series are better, compared to an annual series, for small to medium floods, while both methods produce similar results for large floods. Although both methods converge at a higher recurrence interval, the convergence recurrence interval varies between catchments. Results also suggest frequency estimates vary slightly between two or more partial series, depending on flood threshold, and the differences are large for the catchments that experience less frequent floods. While a partial series produces better frequency estimates, it can underestimate or overestimate the frequency if the flood threshold differs largely compared to bankfull discharge. These results have significant implications in calculating the dependency of floodplain ecosystems on the frequency of flooding and their subsequent management.

  19. Presidential Management Fellows (PMF) Talent Acquisition System, PMF-TAS (ACCESS CONTROLLED)

    Data.gov (United States)

    Office of Personnel Management — Application and Assessment system for Presidential Management Fellows (PMF) and PMF Science, Technology, Engineering, and Math (STEM) programs. This sytem is access...

  20. Maximum Runoff of the Flood on Wadis of Northern Part of Algeria ...

    African Journals Online (AJOL)

    Wadis of Algeria are characterized by a very irregular hydrological regime. The question of estimating the maximum flow of wadis is relevant. We propose in this paper a method based on an interpretation of the transformation of surface runoff in streamflow. The technique of account the maximal runoff of flood for the rivers ...

  1. Dynamic Optimization of a Polymer Flooding Process Based on Implicit Discrete Maximum Principle

    Directory of Open Access Journals (Sweden)

    Yang Lei

    2012-01-01

    Full Text Available Polymer flooding is one of the most important technologies for enhanced oil recovery (EOR. In this paper, an optimal control model of distributed parameter systems (DPSs for polymer injection strategies is established, which involves the performance index as maximum of the profit, the governing equations as the fluid flow equations of polymer flooding, and some inequality constraints as polymer concentration and injection amount limitation. The optimal control model is discretized by full implicit finite-difference method. To cope with the discrete optimal control problem (OCP, the necessary conditions for optimality are obtained through application of the calculus of variations and Pontryagin’s discrete maximum principle. A modified gradient method with new adjoint construction is proposed for the computation of optimal injection strategies. The numerical results of an example illustrate the effectiveness of the proposed method.

  2. Mapping Daily and Maximum Flood Extents at 90-m Resolution During Hurricanes Harvey and Irma Using Passive Microwave Remote Sensing

    Science.gov (United States)

    Galantowicz, J. F.; Picton, J.; Root, B.

    2017-12-01

    Passive microwave remote sensing can provided a distinct perspective on flood events by virtue of wide sensor fields of view, frequent observations from multiple satellites, and sensitivity through clouds and vegetation. During Hurricanes Harvey and Irma, we used AMSR2 (Advanced Microwave Scanning Radiometer 2, JAXA) data to map flood extents starting from the first post-storm rain-free sensor passes. Our standard flood mapping algorithm (FloodScan) derives flooded fraction from 22-km microwave data (AMSR2 or NASA's GMI) in near real time and downscales it to 90-m resolution using a database built from topography, hydrology, and Global Surface Water Explorer data and normalized to microwave data footprint shapes. During Harvey and Irma we tested experimental versions of the algorithm designed to map the maximum post-storm flood extent rapidly and made a variety of map products available immediately for use in storm monitoring and response. The maps have several unique features including spanning the entire storm-affected area and providing multiple post-storm updates as flood water shifted and receded. From the daily maps we derived secondary products such as flood duration, maximum flood extent (Figure 1), and flood depth. In this presentation, we describe flood extent evolution, maximum extent, and local details as detected by the FloodScan algorithm in the wake of Harvey and Irma. We compare FloodScan results to other available flood mapping resources, note observed shortcomings, and describe improvements made in response. We also discuss how best-estimate maps could be updated in near real time by merging FloodScan products and data from other remote sensing systems and hydrological models.

  3. Determination of times maximum insulation in case of internal flooding by pipe break

    International Nuclear Information System (INIS)

    Varas, M. I.; Orteu, E.; Laserna, J. A.

    2014-01-01

    This paper demonstrates the process followed in the preparation of the Manual of floods of Cofrentes NPP to identify the allowed maximum time available to the central in the isolation of a moderate or high energy pipe break, until it affects security (1E) participating in the safe stop of Reactor or in pools of spent fuel cooling-related equipment , and to determine the recommended isolation mode from the point of view of the location of the break or rupture, of the location of the 1E equipment and human factors. (Author)

  4. Modelling non-stationary annual maximum flood heights in the lower Limpopo River basin of Mozambique

    Directory of Open Access Journals (Sweden)

    Daniel Maposa

    2016-05-01

    Full Text Available In this article we fit a time-dependent generalised extreme value (GEV distribution to annual maximum flood heights at three sites: Chokwe, Sicacate and Combomune in the lower Limpopo River basin of Mozambique. A GEV distribution is fitted to six annual maximum time series models at each site, namely: annual daily maximum (AM1, annual 2-day maximum (AM2, annual 5-day maximum (AM5, annual 7-day maximum (AM7, annual 10-day maximum (AM10 and annual 30-day maximum (AM30. Non-stationary time-dependent GEV models with a linear trend in location and scale parameters are considered in this study. The results show lack of sufficient evidence to indicate a linear trend in the location parameter at all three sites. On the other hand, the findings in this study reveal strong evidence of the existence of a linear trend in the scale parameter at Combomune and Sicacate, whilst the scale parameter had no significant linear trend at Chokwe. Further investigation in this study also reveals that the location parameter at Sicacate can be modelled by a nonlinear quadratic trend; however, the complexity of the overall model is not worthwhile in fit over a time-homogeneous model. This study shows the importance of extending the time-homogeneous GEV model to incorporate climate change factors such as trend in the lower Limpopo River basin, particularly in this era of global warming and a changing climate. Keywords: nonstationary extremes; annual maxima; lower Limpopo River; generalised extreme value

  5. THE ESTIMATION OF PMP AND PMF ON ALPINE BASINS IN SWITZERLAND

    Directory of Open Access Journals (Sweden)

    R. Receanu

    2012-03-01

    Full Text Available This paper presents a very fine grid hydrological model based on the spatiotemporal repartition of precipitation and on the topography. The goal is to estimate the flood on a catchment area, using a Probable Maximum Precipitation (PMP leading to a Probable Maximum Flood (PMF. The spatiotemporal distribution of the precipitation was realized using six clouds modeled by the advection-diffusion equation. The equation shows the movement of the clouds over the terrain and also gives the evolution of the rain intensity in time. This hydrological modeling is followed by a hydraulic modeling of the surface and subterranean flows, done considering the factors that contribute to the hydrological cycle, such as the infiltration, the exfiltration and the snowmelt. This model was applied to several Swiss basins using measured rain, with results showing a good correlation between the simulated and observed flows. This good correlation proves that the model is valid and gives us the confidence that the results can be extrapolated to phenomena of extreme rainfall of PMP type. In this article we present some results obtained using a PMP rainfall and the developed model.

  6. Nevada Test Site flood inundation study: Part of US Geological Survey flood potential and debris hazard study, Yucca Mountain Site for USDOE, Office of Civilian Radioactive Waste Management

    International Nuclear Information System (INIS)

    Blanton, J.O. III.

    1992-01-01

    The Geological Survey (GS), as part of the Yucca Mountain Project (YMP), is conducting studies at Yucca Mountain, Nevada. The purposes of these studies are to provide hydrologic and geologic information to evaluate the suitability of Yucca Mountain for development as a high-level nuclear waste repository, and to evaluate the ability of the mined geologic disposal system (MGDS) to isolate the waste in compliance with regulatory requirements. The Bureau of Reclamation was selected by the GS as a contractor to provide probable maximum flood (PMF) magnitudes and associated inundation maps for preliminary engineering design of the surface facilities at Yucca Mountain. These PMF peak flow estimates and associated inundation maps are necessary for successful waste repository design and construction. The standard step method for backwater computations, incorporating the Bernouli energy equation and the results of the PMF study were chosen as the basis for defining the areal extent of flooding

  7. Multi-Temporal Independent Component Analysis and Landsat 8 for Delineating Maximum Extent of the 2013 Colorado Front Range Flood

    Directory of Open Access Journals (Sweden)

    Stephen M. Chignell

    2015-07-01

    Full Text Available Maximum flood extent—a key data need for disaster response and mitigation—is rarely quantified due to storm-related cloud cover and the low temporal resolution of optical sensors. While change detection approaches can circumvent these issues through the identification of inundated land and soil from post-flood imagery, their accuracy can suffer in the narrow and complex channels of increasingly developed and heterogeneous floodplains. This study explored the utility of the Operational Land Imager (OLI and Independent Component Analysis (ICA for addressing these challenges in the unprecedented 2013 Flood along the Colorado Front Range, USA. Pre- and post-flood images were composited and transformed with an ICA to identify change classes. Flooded pixels were extracted using image segmentation, and the resulting flood layer was refined with cloud and irrigated agricultural masks derived from the ICA. Visual assessment against aerial orthophotography showed close agreement with high water marks and scoured riverbanks, and a pixel-to-pixel validation with WorldView-2 imagery captured near peak flow yielded an overall accuracy of 87% and Kappa of 0.73. Additional tests showed a twofold increase in flood class accuracy over the commonly used modified normalized water index. The approach was able to simultaneously distinguish flood-related water and soil moisture from pre-existing water bodies and other spectrally similar classes within the narrow and braided channels of the study site. This was accomplished without the use of post-processing smoothing operations, enabling the important preservation of nuanced inundation patterns. Although flooding beneath moderate and sparse riparian vegetation canopy was captured, dense vegetation cover and paved regions of the floodplain were main sources of omission error, and commission errors occurred primarily in pixels of mixed land use and along the flood edge. Nevertheless, the unsupervised nature of ICA

  8. Release of Volatiles During North Atlantic Flood Basalt Volcanism and Correlation to the Paleocene-Eocene Thermal Maximum

    Science.gov (United States)

    Pedersen, J. M.; Tegner, C.; Kent, A. J.; Ulrich, T.

    2017-12-01

    The opening of the North Atlantic Ocean between Greenland and Norway during the lower Tertiary led to intense flood basalt volcanism and the emplacement of the North Atlantic Igneous Province (NAIP). The volcanism is temporally overlapping with the Paleocene-Eocene Thermal Maximum (PETM), but ash stratigraphy and geochronology suggests that the main flood basalt sequence in East Greenland postdates the PETM. Significant environmental changes during the PETM have been attributed to the release of CO2 or methane gas due to either extensive melting of hydrates at the ocean floor or as a consequence of the interaction of mantle derived magmas with carbon rich sediments.Estimates suggest that a minimum of 1.8x106 km3 of basaltic lava erupted during North Atlantic flood basalt volcanism. Based on measurements of melt inclusions from the flood basalts our preliminary calculations suggest that approximately 2300 Gt of SO2 and 600 Gt of HCl were released into the atmosphere. Calculated yearly fluxes approach 23 Mt/y SO2 and 6 Mt/y HCl. These estimates are regarded as conservative.The S released into to the atmosphere during flood basalt volcanism can form acid aerosols that absorb and reflect solar radiation, causing an effective cooling effect. The climatic effects of the release of Cl into the atmosphere are not well constrained, but may be an important factor for extinction scenarios due to destruction of the ozone layer.The climatic changes due to the release of S and Cl in these amounts, and for periods extending for hundred thousand of years, although not yet fully constrained are likely to be significant. One consequence of the North Atlantic flood basalt volcanism may have been the initiation of global cooling to end the PETM.

  9. A review of the regional maximum flood and rational formula using ...

    African Journals Online (AJOL)

    driniev

    2004-07-03

    Jul 3, 2004 ... The advantage of this method is that the events of large ... The question that arises is “which method is fair to use?” The answer depends ... determined by modelling past floods with an extreme value distri- bution. Even in this ...

  10. 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 ...

  11. Estimating flood inundation caused by dam failures

    Energy Technology Data Exchange (ETDEWEB)

    Mocan, N. [Crozier and Associates Inc., Collingwood, ON (Canada); Joy, D.M. [Guelph Univ., ON (Canada). School of Engineering; Rungis, G. [Grand River Conservation Authority, Cambridge, ON (Canada)

    2006-01-15

    Recent advancements in modelling inundation due to dam failures have allowed easier and more illustrative analyses of potential outcomes. This paper described new model and mapping capabilities available using the HEC-RAS hydraulic model in concert with geographic information systems (GIS). The study area was the upper reaches of Canagagigue Creek and the Woolwich Dam near Elmira, Ontario. A hydraulic analysis of a hypothetical dam failure was developed based on the summer probable maximum flood (PMF) event. Limits extended from Woolwich Dam to downstream of the Town of Elmira. An incoming summer PMF hydrograph was set as the upstream boundary condition in the upstream model. Simulation parameters include simulation time-step; implicit weighting factor; water surface calculation tolerance; and output calculation interval. Peak flows were presented, as well as corresponding flood inundation results through the Town of Elmira. The hydraulic model results were exported to a GIS in order to develop inundation maps for emergency management planning. Results from post-processing included inundation maps for each of the simulated time-steps as well as an inundation animation for the duration of the dam breach. It was concluded that the modelling tools presented in the study can be applied to other dam safety assessment projects in order to develop effective and efficient emergency preparedness plans through public consultation and the establishment of impact zones. 1 tab., 2 figs.

  12. Physical method to assess a probable maximum precipitation, using CRCM datas

    International Nuclear Information System (INIS)

    Beauchamp, J.

    2009-01-01

    'Full text:' For Nordic hydropower facilities, spillways are designed with a peak discharge based on extreme conditions. This peak discharge is generally derived using the concept of a probable maximum flood (PMF), which results from the combined effect of abundant downpours (probable maximum precipitation - PMP) and rapid snowmelt. On a gauged basin, the weather data record allows for the computation of the PMF. However, uncertainty in the future climate raises questions as to the accuracy of current PMP estimates for existing and future hydropower facilities. This project looks at the potential use of the Canadian Regional Climate Model (CRCM) data to compute the PMF in ungauged basins and to assess potential changes to the PMF in a changing climate. Several steps will be needed to accomplish this task. This paper presents the first step that aims at applying/adapting to CRCM data the in situ moisture maximization technique developed by the World Meteorological Organization, in order to compute the PMP at the watershed scale. The CRCM provides output data on a 45km grid at a six hour time step. All of the needed atmospheric data is available at sixteen different pressure levels. The methodology consists in first identifying extreme precipitation events under current climate conditions. Then, a maximum persisting twelve hours dew point is determined at each grid point and pressure level for the storm duration. Afterwards, the maximization ratio is approximated by merging the effective temperature with dew point and relative humidity values. The variables and maximization ratio are four-dimensional (x, y, z, t) values. Consequently, two different approaches are explored: a partial ratio at each step and a global ratio for the storm duration. For every identified extreme precipitation event, a maximized hyetograph is computed from the application of this ratio, either partial or global, on CRCM precipitation rates. Ultimately, the PMP is the depth of the

  13. Physical method to assess a probable maximum precipitation, using CRCM datas

    Energy Technology Data Exchange (ETDEWEB)

    Beauchamp, J. [Univ. de Quebec, Ecole de technologie superior, Quebec (Canada)

    2009-07-01

    'Full text:' For Nordic hydropower facilities, spillways are designed with a peak discharge based on extreme conditions. This peak discharge is generally derived using the concept of a probable maximum flood (PMF), which results from the combined effect of abundant downpours (probable maximum precipitation - PMP) and rapid snowmelt. On a gauged basin, the weather data record allows for the computation of the PMF. However, uncertainty in the future climate raises questions as to the accuracy of current PMP estimates for existing and future hydropower facilities. This project looks at the potential use of the Canadian Regional Climate Model (CRCM) data to compute the PMF in ungauged basins and to assess potential changes to the PMF in a changing climate. Several steps will be needed to accomplish this task. This paper presents the first step that aims at applying/adapting to CRCM data the in situ moisture maximization technique developed by the World Meteorological Organization, in order to compute the PMP at the watershed scale. The CRCM provides output data on a 45km grid at a six hour time step. All of the needed atmospheric data is available at sixteen different pressure levels. The methodology consists in first identifying extreme precipitation events under current climate conditions. Then, a maximum persisting twelve hours dew point is determined at each grid point and pressure level for the storm duration. Afterwards, the maximization ratio is approximated by merging the effective temperature with dew point and relative humidity values. The variables and maximization ratio are four-dimensional (x, y, z, t) values. Consequently, two different approaches are explored: a partial ratio at each step and a global ratio for the storm duration. For every identified extreme precipitation event, a maximized hyetograph is computed from the application of this ratio, either partial or global, on CRCM precipitation rates. Ultimately, the PMP is the depth of the

  14. PMF: the front end electronic of the ALFA detector

    CERN Document Server

    Barrillon, P; Cheikali, C; Cuisy, D; Gaspard, M; Fournier, D; Heller, M; Iwanski, W; Lavigne, B; de La Taille, C; Puzo, P; Socha, J-L

    2008-01-01

    The front end electronic (PMF) of the future ATLAS luminometer is described here. It is composed by a MAPMT and a compact stack of three PCBs which deliver the high voltage, route and readout the output signals. The third board contains a FPGA and MAROC, a 64 channels ASIC which can correct the non uniformity of the MAPMT channels gain thanks to a variable gain preamplifier. Its main role is to shape and discriminate the input signals at 1/3 photo-electron and produce 64 trigger outputs. Laboratory tests performed on prototype and pre-series PMFs have showed performances in good agreement with the requirements.

  15. Evaluation of probable maximum snow accumulation: Development of a methodology for climate change studies

    Science.gov (United States)

    Klein, Iris M.; Rousseau, Alain N.; Frigon, Anne; Freudiger, Daphné; Gagnon, Patrick

    2016-06-01

    Probable maximum snow accumulation (PMSA) is one of the key variables used to estimate the spring probable maximum flood (PMF). A robust methodology for evaluating the PMSA is imperative so the ensuing spring PMF is a reasonable estimation. This is of particular importance in times of climate change (CC) since it is known that solid precipitation in Nordic landscapes will in all likelihood change over the next century. In this paper, a PMSA methodology based on simulated data from regional climate models is developed. Moisture maximization represents the core concept of the proposed methodology; precipitable water being the key variable. Results of stationarity tests indicate that CC will affect the monthly maximum precipitable water and, thus, the ensuing ratio to maximize important snowfall events. Therefore, a non-stationary approach is used to describe the monthly maximum precipitable water. Outputs from three simulations produced by the Canadian Regional Climate Model were used to give first estimates of potential PMSA changes for southern Quebec, Canada. A sensitivity analysis of the computed PMSA was performed with respect to the number of time-steps used (so-called snowstorm duration) and the threshold for a snowstorm to be maximized or not. The developed methodology is robust and a powerful tool to estimate the relative change of the PMSA. Absolute results are in the same order of magnitude as those obtained with the traditional method and observed data; but are also found to depend strongly on the climate projection used and show spatial variability.

  16. PMF: The front end electronic of the ALFA detector

    Energy Technology Data Exchange (ETDEWEB)

    Barrillon, P., E-mail: barrillo@lal.in2p3.f [Laboratoire de l' Accelerateur Lineaire, 91898 Orsay (France); Blin, S.; Cheikali, C.; Cuisy, D.; Gaspard, M.; Fournier, D.; Heller, M. [Laboratoire de l' Accelerateur Lineaire, 91898 Orsay (France); Iwanski, W. [Institute of Nuclear Physics PAN, Radzikowskiego 152, 31-342 Cracow (Poland); Lavigne, B.; De la Taille, C.; Puzo, P.; Socha, J-L. [Laboratoire de l' Accelerateur Lineaire, 91898 Orsay (France)

    2010-11-01

    The front end electronic (PMF) of the future ATLAS luminometer is described here. It is composed of a MAPMT and a compact stack of three PCBs, which deliver high voltage, route and read out of the output signals. The third board contains an FPGA and MAROC, a 64-channel ASIC, which can correct the non-uniformity of the MAPMT channels gain, thanks to a variable gain preamplifier. Its main role is to shape and discriminate the input signals at 1/3 photo-electron and produce 64 trigger outputs. Laboratory tests performed on prototype and pre-series PMFs have showed performances in good agreement with the requirements and have fulfilled the approval criteria for the final production of all elements.

  17. PMF: the front end electronic of the ALFA detector

    CERN Document Server

    Barrillon, P; Cheikali, C; Cuisy, D; Gaspard, M; Fournier, D; Heller, M; Iwanski, W; Lavigne, B; de La Taille, C; Puzo, P; Socha, J-L

    2010-01-01

    The front end electronic (PMF) of the future ATLAS luminometer is described here. It is composed of a MAPMT and a compact stack of three PCBs, which deliver high voltage, route and read out of the output signals. The third board contains an FPGA and MAROC, a 64-channel ASIC, which can correct the non-uniformity of the MAPMT channels gain, thanks to a variable gain preamplifier. Its main role is to shape and discriminate the input signals at 1/3 photo-electron and produce 64 trigger outputs. Laboratory tests performed on prototype and pre-series PMFs have showed performances in good agreement with the requirements and have fulfilled the approval criteria for the final production of all elements.

  18. River flooding due to intense precipitation

    International Nuclear Information System (INIS)

    Lin, James C.

    2014-01-01

    River stage can rise and cause site flooding due to local intense precipitation (LIP), dam failures, snow melt in conjunction with precipitation or dam failures, etc. As part of the re-evaluation of the design basis as well as the PRA analysis of other external events, the likelihood and consequence of river flooding leading to the site flooding need to be examined more rigorously. To evaluate the effects of intense precipitation on site structures, the site watershed hydrology and pond storage are calculated. To determine if river flooding can cause damage to risk-significant systems, structures, and components (SSC), water surface elevations are analyzed. Typically, the amount and rate of the input water is determined first. For intense precipitation, the fraction of the rainfall in the watershed drainage area not infiltrated into the ground is collected in the river and contributes to the rise of river water elevation. For design basis analysis, the Probable Maximum Flood (PMF) is evaluated using the Probable Maximum Precipitation (PMP) based on the site topography/configuration. The peak runoff flow rate and water surface elevations resulting from the precipitation induced flooding can then be estimated. The runoff flow hydrograph and peak discharge flows can be developed using the synthetic hydrograph method. The standard step method can then be used to determine the water surface elevations along the river channel. Thus, the flood water from the local intense precipitation storm and excess runoff from the nearby river can be evaluated to calculate the water surface elevations, which can be compared with the station grade floor elevation to determine the effects of site flooding on risk-significant SSCs. The analysis needs to consider any possible diversion flow and the effects of changes to the site configurations. Typically, the analysis is performed based on conservative peak rainfall intensity and the assumptions of failure of the site drainage facilities

  19. Floods and Flash Flooding

    Science.gov (United States)

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

  20. Qualified measurement setup of polarization extinction ratio for Panda PMF with LC/UPC connector

    Science.gov (United States)

    Thongdaeng, Rutsuda; Worasucheep, Duang-rudee; Ngiwprom, Adisak

    2018-03-01

    Polarization Extinction Ratio (PER) is one of the key parameters for Polarization Maintaining Fiber (PMF) connector. Based on our previous studies, the bending radius of fiber greater than 1.5 cm will not affect the insertion loss of PMF [1]. Moreover, the measured PER of Panda PMF with LC/UPC connectors is more stable when that PMF is coiled around a hot rod with a minimum of 3-cm in diameter at 75°C temperature [2]. Hence, the hot rod with less constrained 6-cm in diameter at constant 75°C was selected for this PER measurement. Two PER setups were verified and compared for measuring LC/UPC PMF connectors. The Polarized Laser Source (PLS) at 1550 nm wavelength and PER meter from OZ Optics were used in both setups, in which the measured connector was connected to PLS at 0° angle while the other end was connected to PER meter. In order to qualify our setups, the percentage of Repeatability and Reproducibility (%R&R) were tested and calculated. In each setup, the PER measurement was repeated 3 trials by 3 appraisers using 10 LC/UPC PMF connectors (5 LC/UPC PMF patchcords with 3.5+/-0.5 meters in length) in random order. The 1st setup, PMF was coiled at a larger 20-cm diameter for 3 to 5 loops and left in room temperature during the test. The 2nd setup, PMF was coiled around a hot rod at constant 75°C with 6-cm diameter for 8 to 10 loops for at least 5 minutes before testing. There are 3 ranges of %R&R acceptation guide line: <10% is acceptable, between 10% - 30% is marginal, and <30% is unacceptable. According to our results, the %R&R of the 1st PER test setup was 16.2% as marginality, and the 2nd PER test setup was 8.9% as acceptance. Thus, providing the better repeatability and reproducibility, this 2nd PER test setup having PMF coiled around a hot rod at constant 75°C with 6-cm diameter was selected for our next study of the impact of hot temperature on PER in LC/UPC PMF connector.

  1. 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.

  2. Methods for estimating uncertainty in PMF solutions: examples with ambient air and water quality data and guidance on reporting PMF results.

    Science.gov (United States)

    Brown, Steven G; Eberly, Shelly; Paatero, Pentti; Norris, Gary A

    2015-06-15

    The new version of EPA's positive matrix factorization (EPA PMF) software, 5.0, includes three error estimation (EE) methods for analyzing factor analytic solutions: classical bootstrap (BS), displacement of factor elements (DISP), and bootstrap enhanced by displacement (BS-DISP). These methods capture the uncertainty of PMF analyses due to random errors and rotational ambiguity. To demonstrate the utility of the EE methods, results are presented for three data sets: (1) speciated PM2.5 data from a chemical speciation network (CSN) site in Sacramento, California (2003-2009); (2) trace metal, ammonia, and other species in water quality samples taken at an inline storage system (ISS) in Milwaukee, Wisconsin (2006); and (3) an organic aerosol data set from high-resolution aerosol mass spectrometer (HR-AMS) measurements in Las Vegas, Nevada (January 2008). We present an interpretation of EE diagnostics for these data sets, results from sensitivity tests of EE diagnostics using additional and fewer factors, and recommendations for reporting PMF results. BS-DISP and BS are found useful in understanding the uncertainty of factor profiles; they also suggest if the data are over-fitted by specifying too many factors. DISP diagnostics were consistently robust, indicating its use for understanding rotational uncertainty and as a first step in assessing a solution's viability. The uncertainty of each factor's identifying species is shown to be a useful gauge for evaluating multiple solutions, e.g., with a different number of factors. Published by Elsevier B.V.

  3. Determination of times maximum insulation in case of internal flooding by pipe break; Determinacion de los tiempos maximos de aislamiento en caso de inundacion interna por rotura de tuberia

    Energy Technology Data Exchange (ETDEWEB)

    Varas, M. I.; Orteu, E.; Laserna, J. A.

    2014-07-01

    This paper demonstrates the process followed in the preparation of the Manual of floods of Cofrentes NPP to identify the allowed maximum time available to the central in the isolation of a moderate or high energy pipe break, until it affects security (1E) participating in the safe stop of Reactor or in pools of spent fuel cooling-related equipment , and to determine the recommended isolation mode from the point of view of the location of the break or rupture, of the location of the 1E equipment and human factors. (Author)

  4. Flood and rockslide mitigative measures for the concrete sections of the Daisy Lake Dam

    International Nuclear Information System (INIS)

    Pataky, T.J.

    1991-01-01

    Studies conducted under British Columbia Hydro's dam safety program during the early 1980s indicated that dam sections of the Daisy Lake Dam would be overtopped by the probable maximum flood (PMF) and by a postulated slide generated wave (SGW). It was considered that the overtopping by either of the events could cause several sections of the concrete dam to fall, thereby resulting in uncontrolled release of the reservoir. The criteria used for determining foundation strength parameters, static and SGW induced water pressures, effective uplift and the appropriate factors of safety are discussed. The results of the analyses for the original dam sections and the design and implementation of the selected remedial measures are also described. These measures included lowering the Wing Dam and Saddle Dam by about 2 m to increase the spillway capacity and the installation of 43 post-tensioned anchors in the various sections of the main concrete and Wing dams. 9 refs., 8 figs., 3 tabs

  5. The Impacts of Pelosika and Ameroro Dams in the Flood Control Performance of Konaweha River

    Directory of Open Access Journals (Sweden)

    Arif Sidik

    2016-09-01

    Full Text Available Konaweeha watershed is the largest watershed in Southeast Sulawesi with Konaweeha River as the main river. The main issues in Konaweeha Watershed is floods that occur caused damage to infrastructure and public facilities, lowering agricultural production, and cause fatalities. One of the government's efforts to cope with the flooding problem in Konaweeha Watershed is planning the construction of multi-purpose dams in the upstream of Konaweeha Watershed that is Pelosika Dam and Ameroso Dam. Necessary to study the flood control performance of the two dams. Analyses were performed with hydrologic-hydraulic modeling using HEC-HMS software (Hydrologic Modelling System version 4.0 and HEC-RAS (River Analysis System version 4.1. The design rainfalls that were used as input to the model were 2 year, 5-year, 10-year and 25 year. Scenarios used in this study are: (1 Existing Scenario (2 Pelosika Dam Scenario; (3 Ameroro Dam Scenario; (4 Pelosika and Ameroro Dams Scenario. The results showed the maximum water surface elevation along the downstream of Konaweeha River in Scenario (2 and (4 were almost the same in the 2 and 5 years return period design flood. However, in case of 10 and 25 years return period, the difference of maximum water surface elevation at downstream of Konaweeha River was slightly significant. Furthermore, the damping efficiency of the peak discharge (at Probably Maximum Flood or PMF was found to be 71.70% and 18.18% for the individual Pelosika Dam and Ameroro Dam respectively. Further discussion suggests the development of Pelosika Dam as the higher priority rather than that of the Ameroro Dam.

  6. Calculation of Collective Variable-based PMF by Combining WHAM with Umbrella Sampling

    International Nuclear Information System (INIS)

    Xu Wei-Xin; Li Yang; Zhang, John Z. H.

    2012-01-01

    Potential of mean force (PMF) with respect to localized reaction coordinates (RCs) such as distance is often applied to evaluate the free energy profile along the reaction pathway for complex molecular systems. However, calculation of PMF as a function of global RCs is still a challenging and important problem in computational biology. We examine the combined use of the weighted histogram analysis method and the umbrella sampling method for the calculation of PMF as a function of a global RC from the coarse-grained Langevin dynamics simulations for a model protein. The method yields the folding free energy profile projected onto a global RC, which is in accord with benchmark results. With this method rare global events would be sufficiently sampled because the biased potential can be used for restricting the global conformation to specific regions during free energy calculations. The strategy presented can also be utilized in calculating the global intra- and intermolecular PMF at more detailed levels. (cross-disciplinary physics and related areas of science and technology)

  7. Predicting location-specific extreme coastal floods in the future climate by introducing a probabilistic method to calculate maximum elevation of the continuous water mass caused by a combination of water level variations and wind waves

    Science.gov (United States)

    Leijala, Ulpu; Björkqvist, Jan-Victor; Johansson, Milla M.; Pellikka, Havu

    2017-04-01

    Future coastal management continuously strives for more location-exact and precise methods to investigate possible extreme sea level events and to face flooding hazards in the most appropriate way. Evaluating future flooding risks by understanding the behaviour of the joint effect of sea level variations and wind waves is one of the means to make more comprehensive flooding hazard analysis, and may at first seem like a straightforward task to solve. Nevertheless, challenges and limitations such as availability of time series of the sea level and wave height components, the quality of data, significant locational variability of coastal wave height, as well as assumptions to be made depending on the study location, make the task more complicated. In this study, we present a statistical method for combining location-specific probability distributions of water level variations (including local sea level observations and global mean sea level rise) and wave run-up (based on wave buoy measurements). The goal of our method is to obtain a more accurate way to account for the waves when making flooding hazard analysis on the coast compared to the approach of adding a separate fixed wave action height on top of sea level -based flood risk estimates. As a result of our new method, we gain maximum elevation heights with different return periods of the continuous water mass caused by a combination of both phenomena, "the green water". We also introduce a sensitivity analysis to evaluate the properties and functioning of our method. The sensitivity test is based on using theoretical wave distributions representing different alternatives of wave behaviour in relation to sea level variations. As these wave distributions are merged with the sea level distribution, we get information on how the different wave height conditions and shape of the wave height distribution influence the joint results. Our method presented here can be used as an advanced tool to minimize over- and

  8. The Cytotoxic Effect of Small and Large Molecules of PMF Fraction Extracted from Camel Urine on Cancer Cells

    KAUST Repository

    Khorshid, Faten

    2015-01-10

    Aim of the work: Animal urine, including that of camels, has long been used for the therapeutic management of human ailments. In this study, we sought to characterize the cytotoxic properties of newly derived purified fractions from previously described camel urine extract (PMF) on various cancer cell lines. Methodology: Two new size dissimilar fractions of PMF (large and small) were obtained by fractionalizing PMF using 3kD and 50kD membrane filters. A SRB cytotoxicity assay of the PMF fractions was performed on cancer cell lines (A549, HCT116, HepG2, MCF-7, U251 and Hela) as well as normal cell lines (human fibroblast cell line and Vero). Results: This study showed that the newly derived and more purified fraction of PMF (new PMF) possesses effective and selective anti-cancer properties against several types of cancer cell lines. Conclusion: This study, as well as previous ones, suggests that camel urine extracts (old and new PMF) may provide newer therapeutic alternatives to clinically manage cancer patients. However, further studies are needed to verify these positive preliminary results.

  9. Quantifying road dust resuspension in urban environment by Multilinear Engine: A comparison with PMF2

    Science.gov (United States)

    Amato, F.; Pandolfi, M.; Escrig, A.; Querol, X.; Alastuey, A.; Pey, J.; Perez, N.; Hopke, P. K.

    Atmospheric PM pollution from traffic comprises not only direct emissions but also non-exhaust emissions because resuspension of road dust that can produce high human exposure to heavy metals, metalloids, and mineral matter. A key task for establishing mitigation or preventive measures is estimating the contribution of road dust resuspension to the atmospheric PM mixture. Several source apportionment studies, applying receptor modeling at urban background sites, have shown the difficulty in identifying a road dust source separately from other mineral sources or vehicular exhausts. The Multilinear Engine (ME-2) is a computer program that can solve the Positive Matrix Factorization (PMF) problem. ME-2 uses a programming language permitting the solution to be guided toward some possible targets that can be derived from a priori knowledge of sources (chemical profile, ratios, etc.). This feature makes it especially suitable for source apportionment studies where partial knowledge of the sources is available. In the present study ME-2 was applied to data from an urban background site of Barcelona (Spain) to quantify the contribution of road dust resuspension to PM 10 and PM 2.5 concentrations. Given that recently the emission profile of local resuspended road dust was obtained (Amato, F., Pandolfi, M., Viana, M., Querol, X., Alastuey, A., Moreno, T., 2009. Spatial and chemical patterns of PM 10 in road dust deposited in urban environment. Atmospheric Environment 43 (9), 1650-1659), such a priori information was introduced in the model as auxiliary terms of the object function to be minimized by the implementation of the so-called "pulling equations". ME-2 permitted to enhance the basic PMF solution (obtained by PMF2) identifying, beside the seven sources of PMF2, the road dust source which accounted for 6.9 μg m -3 (17%) in PM 10, 2.2 μg m -3 (8%) of PM 2.5 and 0.3 μg m -3 (2%) of PM 1. This reveals that resuspension was responsible of the 37%, 15% and 3% of total

  10. The Cytotoxic Effect of Small and Large Molecules of PMF Fraction Extracted from Camel Urine on Cancer Cells

    KAUST Repository

    Khorshid, Faten; Emwas, Abdul-Hamid M.; Mahboub, Faiza

    2015-01-01

    Conclusion: This study, as well as previous ones, suggests that camel urine extracts (old and new PMF) may provide newer therapeutic alternatives to clinically manage cancer patients. However, further studies are needed to verify these positive preliminary results.

  11. Probable Maximum Precipitation (PMP) over mountainous region of Cameron Highlands- Batang Padang Catchment of Malaysia

    Science.gov (United States)

    Sidek, L. M.; Mohd Nor, M. D.; Rakhecha, P. R.; Basri, H.; Jayothisa, W.; Muda, R. S.; Ahmad, M. N.; Razad, A. Z. Abdul

    2013-06-01

    The Cameron Highland Batang Padang (CHBP) catchment situated on the main mountain range of Peninsular Malaysia is of large economical importance where currently a series of three dams (Sultan Abu Bakar, Jor and Mahang) exist in the development of water resources and hydropower. The prediction of the design storm rainfall values for different return periods including PMP values can be useful to review the adequacy of the current spillway capacities of these dams. In this paper estimates of the design storm rainfalls for various return periods and also the PMP values for rainfall stations in the CHBP catchment have been computed for the three different durations of 1, 3 & 5 days. The maximum values for 1 day, 3 days and 5 days PMP values are found to be 730.08mm, 966.17mm and 969.0mm respectively at Station number 4513033 Gunung Brinchang. The PMP values obtained were compared with previous study results undertaken by NAHRIM. However, the highest ratio of 1 day, 3 day and 5 day PMP to highest observed rainfall are found to be 2.30, 1.94 and 1.82 respectively. This shows that the ratio tend to decrease as the duration increase. Finally, the temporal pattern for 1 day, 3day and 5 days have been developed based on observed extreme rainfall at station 4513033 Gunung Brinchang for the generation of Probable Maximum Flood (PMF) in dam break analysis.

  12. Probable Maximum Precipitation (PMP) over mountainous region of Cameron Highlands- Batang Padang Catchment of Malaysia

    International Nuclear Information System (INIS)

    Sidek, L M; Basri, H; Jayothisa, W; Nor, M D Mohd; Rakhecha, P R; Muda, R S; Ahmad, M N; Razad, A Z Abdul

    2013-01-01

    The Cameron Highland Batang Padang (CHBP) catchment situated on the main mountain range of Peninsular Malaysia is of large economical importance where currently a series of three dams (Sultan Abu Bakar, Jor and Mahang) exist in the development of water resources and hydropower. The prediction of the design storm rainfall values for different return periods including PMP values can be useful to review the adequacy of the current spillway capacities of these dams. In this paper estimates of the design storm rainfalls for various return periods and also the PMP values for rainfall stations in the CHBP catchment have been computed for the three different durations of 1, 3 and 5 days. The maximum values for 1 day, 3 days and 5 days PMP values are found to be 730.08mm, 966.17mm and 969.0mm respectively at Station number 4513033 Gunung Brinchang. The PMP values obtained were compared with previous study results undertaken by NAHRIM. However, the highest ratio of 1 day, 3 day and 5 day PMP to highest observed rainfall are found to be 2.30, 1.94 and 1.82 respectively. This shows that the ratio tend to decrease as the duration increase. Finally, the temporal pattern for 1 day, 3day and 5 days have been developed based on observed extreme rainfall at station 4513033 Gunung Brinchang for the generation of Probable Maximum Flood (PMF) in dam break analysis.

  13. Accounting for Intraligand Interactions in Flexible Ligand Docking with a PMF-Based Scoring Function.

    Science.gov (United States)

    Lizunov, A Y; Gonchar, A L; Zaitseva, N I; Zosimov, V V

    2015-10-26

    We analyzed the frequency with which intraligand contacts occurred in a set of 1300 protein-ligand complexes [ Plewczynski et al. J. Comput. Chem. 2011 , 32 , 742 - 755 .]. Our analysis showed that flexible ligands often form intraligand hydrophobic contacts, while intraligand hydrogen bonds are rare. The test set was also thoroughly investigated and classified. We suggest a universal method for enhancement of a scoring function based on a potential of mean force (PMF-based score) by adding a term accounting for intraligand interactions. The method was implemented via in-house developed program, utilizing an Algo_score scoring function [ Ramensky et al. Proteins: Struct., Funct., Genet. 2007 , 69 , 349 - 357 .] based on the Tarasov-Muryshev PMF [ Muryshev et al. J. Comput.-Aided Mol. Des. 2003 , 17 , 597 - 605 .]. The enhancement of the scoring function was shown to significantly improve the docking and scoring quality for flexible ligands in the test set of 1300 protein-ligand complexes [ Plewczynski et al. J. Comput. Chem. 2011 , 32 , 742 - 755 .]. We then investigated the correlation of the docking results with two parameters of intraligand interactions estimation. These parameters are the weight of intraligand interactions and the minimum number of bonds between the ligand atoms required to take their interaction into account.

  14. Source Apportionment of PM2.5 in Delhi, India Using PMF Model.

    Science.gov (United States)

    Sharma, S K; Mandal, T K; Jain, Srishti; Saraswati; Sharma, A; Saxena, Mohit

    2016-08-01

    Chemical characterization of PM2.5 [organic carbon, elemental carbon, water soluble inorganic ionic components, and major and trace elements] was carried out for a source apportionment study of PM2.5 at an urban site of Delhi, India from January, 2013, to December, 2014. The annual average mass concentration of PM2.5 was 122 ± 94.1 µg m(-3). Strong seasonal variation was observed in PM2.5 mass concentration and its chemical composition with maxima during winter and minima during monsoon. A receptor model, positive matrix factorization (PMF) was applied for source apportionment of PM2.5 mass concentration. The PMF model resolved the major sources of PM2.5 as secondary aerosols (21.3 %), followed by soil dust (20.5 %), vehicle emissions (19.7 %), biomass burning (14.3 %), fossil fuel combustion (13.7 %), industrial emissions (6.2 %) and sea salt (4.3 %).

  15. Fuel Coolant Interaction Results in the Fuel Pins Melting Facility (PMF)

    International Nuclear Information System (INIS)

    Urunashi, H.; Hirabayashi, T.; Mizuta, H.

    1976-01-01

    The experimental work related to FCI at PNC has been concentrated into the molten UO 2 dropping test. After the completion of molten UO 2 drop experiments, emphasis is directed toward the FCI phenomena of the initiating conditions of the accident under the more realistic geometry. The experiments are conducted within the Pin Melt Facility (PMF) in which UO 2 pellets clad in stainless steel are melted by direct electric heating under the stagnant or flowing sodium. The primary objectives of the PMF test are to: - obtain detail experimental results (heat-input, clad temperature, sodium temperature, etc.) on the FCI under TOP and LOF conditions; - observe the movement of the fuel before and after the pin failure by the X-ray cinematography; - observe the degree of coherence of the pin failures; - accumulate the experience of the FCI experiment which is applicable to the subassembly or more larger scale; - simulate the fuel behavior of the in-pile test (GETR, CABRI). The preliminary conclusions can be drawn from the foregoing observations are as follows: - Although the fuel motion and FCI of the closed test section appeared to be different from those of the open test section, the conclusion of the effect of the inside pressure on FCI needs more experimental data. - The best heating condition of the UO 2 pellet for the FCI study with PMF is established as 40 w/cm at the steady state and 1680 J/g of UO 2 during the additional transient state. The total energy deposition of the UO 2 pellet is thus estimated in the range of 2400 J/g of UO 2 -2600 J/g of UO 2 . The analytical model of the fuel pin failure and the subsequent FCI are suggested to count the following parameters: - The fuel pin failure due to the fuel vaporization due to the rapid energy deposition; - Molten fuel, clad and sodium interaction in the fuel pin after the pin failure; - The upward flow of molten fuel with molten clad or vapor sodium, as well as the slumping of molten fuel

  16. Receptor modelling with PMF2 and ME2 using aerosol data from Hong Kong

    International Nuclear Information System (INIS)

    Crawford, J.; Cohen, D.; Dyer, L.; Zahorowski, W.

    2005-01-01

    A number of techniques, such as principal component analysis and factor analysis, have been used in receptor modelling where measured aerosol composition at the sampling site are analysed in order to determine the likely source contributions. In this study factor analysis with non-negative factor elements has been carried out using two techniques as implemented in the PMF2 and ME2 computer codes. The various analysis techniques provided by the two programs are illustrated using measured data at Hong Kong as a case study, which covers a period of three years (2001 to 2003). Both analysis techniques resulted in similar results which are presented in this report. Data bootstrapping was also carried out as an additional check on the quality of the results

  17. Development of a Prototype Web GIS-Based Disaster Management System for Safe Operation of the Next Generation Bimodal Tram, South Korea—Focused Flooding and Snowfall

    Directory of Open Access Journals (Sweden)

    Won Seok Jang

    2014-04-01

    Full Text Available The Korea Railroad Research Institute (KRRI has developed a bimodal tram and advanced bus rapid transit (BRT system which is an optimized public transit system created by mixing the railway’s punctual operation and the bus’ easy and convenient access. The bimodal tram system provides mass-transportation service with an eco-friendly and human-centered approach. Natural disasters have been increasing worldwide in recent years, including floods, snow, and typhoons disasters. Flooding is the most frequent natural disaster in many countries and is increasingly a concern with climate change; it seriously affects people’s lives and productivity, causing considerable economic loss and significant damage. Enhanced conventional disaster management systems are needed to support comprehensive actions to secure safety and convenience. The objective of this study is to develop a prototype version of a Web GIS-based bimodal tram disaster management system (BTDMS using the Storm Water Management Model (SWMM 5.0 to enhance on-time operation and safety of the bimodal tram system. The BTDMS was tested at the bimodal tram test railroad by simulating probable maximum flood (PMF and snow melting for forecasting flooding and snow covered roads. This result could provide the basis for plans to protect against flooding disasters and snow covered roads in operating the bimodal tram system. The BTDMS will be used to assess and predict weather impacts on roadway conditions and operations and thus has the potential to influence economic growth. The methodology presented in this paper makes it possible to manage impacts of flooding and snowfall on urban transportation and enhance operation of the bimodal tram system. Such a methodology based on modeling could be created for most metropolitan areas in Korea and in many other countries.

  18. Exploitation of Documented Historical Floods for Achieving Better Flood Defense

    Directory of Open Access Journals (Sweden)

    Slobodan Kolaković

    2016-01-01

    Full Text Available Establishing Base Flood Elevation for a stream network corresponding to a big catchment is feasible by interdisciplinary approach, involving stochastic hydrology, river hydraulics, and computer aided simulations. A numerical model calibrated by historical floods has been exploited in this study. The short presentation of the catchment of the Tisza River in this paper is followed by the overview of historical floods which hit the region in the documented period of 130 years. Several well documented historical floods provided opportunity for the calibration of the chosen numerical model. Once established, the model could be used for investigation of different extreme flood scenarios and to establish the Base Flood Elevation. The calibration has shown that the coefficient of friction in case of the Tisza River is dependent both on the actual water level and on the preceding flood events. The effect of flood plain maintenance as well as the activation of six potential detention ponds on flood mitigation has been examined. Furthermore, the expected maximum water levels have also been determined for the case if the ever observed biggest 1888 flood hit the region again. The investigated cases of flood superposition highlighted the impact of tributary Maros on flood mitigation along the Tisza River.

  19. Study on the Application of the Combination of TMD Simulation and Umbrella Sampling in PMF Calculation for Molecular Conformational Transitions

    Directory of Open Access Journals (Sweden)

    Qing Wang

    2016-05-01

    Full Text Available Free energy calculations of the potential of mean force (PMF based on the combination of targeted molecular dynamics (TMD simulations and umbrella samplings as a function of physical coordinates have been applied to explore the detailed pathways and the corresponding free energy profiles for the conformational transition processes of the butane molecule and the 35-residue villin headpiece subdomain (HP35. The accurate PMF profiles for describing the dihedral rotation of butane under both coordinates of dihedral rotation and root mean square deviation (RMSD variation were obtained based on the different umbrella samplings from the same TMD simulations. The initial structures for the umbrella samplings can be conveniently selected from the TMD trajectories. For the application of this computational method in the unfolding process of the HP35 protein, the PMF calculation along with the coordinate of the radius of gyration (Rg presents the gradual increase of free energies by about 1 kcal/mol with the energy fluctuations. The feature of conformational transition for the unfolding process of the HP35 protein shows that the spherical structure extends and the middle α-helix unfolds firstly, followed by the unfolding of other α-helices. The computational method for the PMF calculations based on the combination of TMD simulations and umbrella samplings provided a valuable strategy in investigating detailed conformational transition pathways for other allosteric processes.

  20. Consistency of extreme flood estimation approaches

    Science.gov (United States)

    Felder, Guido; Paquet, Emmanuel; Penot, David; Zischg, Andreas; Weingartner, Rolf

    2017-04-01

    Estimations of low-probability flood events are frequently used for the planning of infrastructure as well as for determining the dimensions of flood protection measures. There are several well-established methodical procedures to estimate low-probability floods. However, a global assessment of the consistency of these methods is difficult to achieve, the "true value" of an extreme flood being not observable. Anyway, a detailed comparison performed on a given case study brings useful information about the statistical and hydrological processes involved in different methods. In this study, the following three different approaches for estimating low-probability floods are compared: a purely statistical approach (ordinary extreme value statistics), a statistical approach based on stochastic rainfall-runoff simulation (SCHADEX method), and a deterministic approach (physically based PMF estimation). These methods are tested for two different Swiss catchments. The results and some intermediate variables are used for assessing potential strengths and weaknesses of each method, as well as for evaluating the consistency of these methods.

  1. Flooding correlations in narrow channel

    International Nuclear Information System (INIS)

    Kim, S. H.; Baek, W. P.; Chang, S. H.

    1999-01-01

    Heat transfer in narrow gap is considered as important phenomena in severe accidents in nuclear power plants. Also in heat removal of electric chip. Critical heat flux(CHF) in narrow gap limits the maximum heat transfer rate in narrow channel. In case of closed bottom channel, flooding limited CHF occurrence is observed. Flooding correlations will be helpful to predict the CHF in closed bottom channel. In present study, flooding data for narrow channel geometry were collected and the work to recognize the effect of the span, w and gap size, s were performed. And new flooding correlations were suggested for high-aspect-ratio geometry. Also, flooding correlation was applied to flooding limited CHF data

  2. Identification of flood-rich and flood-poor periods in flood series

    Science.gov (United States)

    Mediero, Luis; Santillán, David; Garrote, Luis

    2015-04-01

    Recently, a general concern about non-stationarity of flood series has arisen, as changes in catchment response can be driven by several factors, such as climatic and land-use changes. Several studies to detect trends in flood series at either national or trans-national scales have been conducted. Trends are usually detected by the Mann-Kendall test. However, the results of this test depend on the starting and ending year of the series, which can lead to different results in terms of the period considered. The results can be conditioned to flood-poor and flood-rich periods located at the beginning or end of the series. A methodology to identify statistically significant flood-rich and flood-poor periods is developed, based on the comparison between the expected sampling variability of floods when stationarity is assumed and the observed variability of floods in a given series. The methodology is applied to a set of long series of annual maximum floods, peaks over threshold and counts of annual occurrences in peaks over threshold series observed in Spain in the period 1942-2009. Mediero et al. (2014) found a general decreasing trend in flood series in some parts of Spain that could be caused by a flood-rich period observed in 1950-1970, placed at the beginning of the flood series. The results of this study support the findings of Mediero et al. (2014), as a flood-rich period in 1950-1970 was identified in most of the selected sites. References: Mediero, L., Santillán, D., Garrote, L., Granados, A. Detection and attribution of trends in magnitude, frequency and timing of floods in Spain, Journal of Hydrology, 517, 1072-1088, 2014.

  3. Receptor modeling of near-roadway aerosol mass spectrometer data in Las Vegas, Nevada, with EPA PMF

    Directory of Open Access Journals (Sweden)

    S. G. Brown

    2012-01-01

    Full Text Available Ambient non-refractory PM1 aerosol particles were measured with an Aerodyne High Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-AMS at an elementary school 18 m from the US 95 freeway soundwall in Las Vegas, Nevada, during January 2008. Additional collocated continuous measurements of black carbon (BC, carbon monoxide (CO, nitrogen oxides (NOx, and meteorological data were collected. The US~Environmental Protection Agency's (EPA positive matrix factorization (PMF data analysis tool was used to apportion organic matter (OM as measured by HR-AMS, and rotational tools in EPA PMF were used to better characterize the solution space and pull resolved factors toward known source profiles. Three- to six-factor solutions were resolved. The four-factor solution was the most interpretable, with the typical AMS PMF factors of hydrocarbon-like organic aerosol (HOA, low-volatility oxygenated organic aerosol (LV-OOA, biomass burning organic aerosol (BBOA, and semi-volatile oxygenated organic aerosol (SV-OOA. When the measurement site was downwind of the freeway, HOA composed about half the OM, with SV-OOA and LV-OOA accounting for the rest. Attempts to pull the PMF factor profiles toward source profiles were successful but did not qualitatively change the results, indicating that these factors are very stable. Oblique edges were present in G-space plots, suggesting that the obtained rotation may not be the most plausible one. Since solutions found by pulling the profiles or using Fpeak retained these oblique edges, there appears to be little rotational freedom in the base solution. On average, HOA made up 26% of the OM, while LV-OOA was highest in the afternoon and accounted for 26% of the OM. BBOA occurred in the evening hours, was predominantly from the residential area to the north, and on average constituted 12% of the OM; SV-OOA accounted for the remaining third of the OM. Use of the pulling techniques

  4. 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

  5. PMF5.0 vs. CMB8.2: An inter-comparison study based on the new European SPECIEUROPE database

    Science.gov (United States)

    Bove, Maria Chiara; Massabò, Dario; Prati, Paolo

    2018-03-01

    Receptor Models are tools widely adopted in source apportionment studies. We describe here an experiment in which we integrated two different approaches, i.e. Positive Matrix Factorization (PMF) and Chemical Mass Balance (CMB) to apportion a set of PM10 (i.e. Particulate Matter with aerodynamic diameter lower than 10 μm) concentration values. The study was performed in the city of Genoa (Italy): a sampling campaign was carried out collecting daily PM10 samples for about two months in an urban background site. PM10 was collected on Quartz fiber filters by a low-volume sampler. A quite complete speciation of PM samples was obtained via Energy Dispersive-X Ray Fluorescence (ED-XRF, for elements), Ionic Chromatography (IC, for major ions and levoglucosan), thermo-optical Analysis (TOT, for organic and elemental carbon). The chemical analyses provided the input database for source apportionment by both PMF and CMB. Source profiles were directly calculated from the input data by PMF while in the CMB runs they were first calculated by averaging the profiles of similar sources collected in the European database SPECIEUROPE. Differences between the two receptor models emerged in particular with PM10 sources linked to very local processes. For this reason, PMF source profiles were adopted in refined CMB runs thus testing a new hybrid approach. Finally, PMF and the "tuned" CMB showed a better agreement even if some discrepancies could not completely been resolved. In this work, we compared the results coming from the last available PMF and CMB versions applied on a set of PM10 samples. Input profiles used in CMB analysis were obtained by averaging the profiles of the new European SPECIEUROPE database. The main differences between PMF and CMB results were linked to very local processes: we obtained the best solution by integrating the two different approaches with the implementation of some output PMF profiles to CMB runs.

  6. Floods in Serbia in the 1999-2009 period: Hydrological analysis and flood protection measures

    Directory of Open Access Journals (Sweden)

    Milanović Ana

    2010-01-01

    Full Text Available The review on greatest floods recorded in Vojvodina and central Serbia within the period from 1999 to 2009 is given in this paper. For 13 hydrological stations, that recorded the greatest floods for the present period, probability of occurrence of these floods has been accomplished. Based on analysis of time series of discharge and water level maximum, performed by applying probability theory and mathematical statistics, and calculated theoretical probability distribution function of floods, probability of occurrence of flood has been obtained. Most often the best agreement with the empirical distribution function had a Log-Pearson III, Pearson III distribution. These results can be used for dimensioning of hydro-technical objects for flood protection. The most significant causes for floods recorded in this period were melting of snow and intensive rainfall. In this paper the current situation of flood protection and future development of flood protection measures were also presented. .

  7. PMF and PSCF based source apportionment of PM2.5 at a regional background site in North China

    Science.gov (United States)

    Zong, Zheng; Wang, Xiaoping; Tian, Chongguo; Chen, Yingjun; Fu, Shanfei; Qu, Lin; Ji, Ling; Li, Jun; Zhang, Gan

    2018-05-01

    To apportion regional PM2.5 (atmospheric particles with aerodynamic diameter water-soluble ions and inorganic elements, various approaches, such as Mann-Kendall test, chemical mass closure, ISORROPIA II model, Positive Matrix Factorization (PMF) linked with Potential Source Contribution Function (PSCF), were used to explore the PM2.5 speciation, sources, and source regions. Consequently, distinct seasonal variations of PM2.5 and its main species were found and could be explained by varying emission source characteristics. Based on PMF model, seven source factors for PM2.5 were identified, which were coal combustion + biomass burning, vehicle emission, mineral dust, ship emission, sea salt, industry source, refined chrome industry with the contribution of 48.21%, 30.33%, 7.24%, 6.63%, 3.51%, 3.2%, and 0.88%, respectively. In addition, PSCF analysis using the daily contribution of each factor from PMF result suggested that Shandong peninsula and Hebei province were identified as the high potential region for coal combustion + biomass burning; Beijing-Tianjin-Hebei (BTH) region was the main source region for industry source; Bohai Sea and East China Sea were found to be of high source potential for ship emission; Geographical region located northwest of BH Island was possessed of high probability for sea salt; Mineral dust presumably came from the region of Mongolia; Refined chrome industry mostly came from Liaoning, Jilin province; The vehicle emission was primarily of BTH region origin, centring on metropolises, such as Beijing and Tianjin. These results provided precious implications for PM2.5 control strategies in North China.

  8. Towards a Flood Severity Index

    Science.gov (United States)

    Kettner, A.; Chong, A.; Prades, L.; Brakenridge, G. R.; Muir, S.; Amparore, A.; Slayback, D. A.; Poungprom, R.

    2017-12-01

    Flooding is the most common natural hazard worldwide, affecting 21 million people every year. In the immediate moments following a flood event, humanitarian actors like the World Food Program need to make rapid decisions ( 72 hrs) on how to prioritize affected areas impacted by such an event. For other natural disasters like hurricanes/cyclones and earthquakes, there are industry-recognized standards on how the impacted areas are to be classified. Shake maps, quantifying peak ground motion, from for example the US Geological Survey are widely used for assessing earthquakes. Similarly, cyclones are tracked by Joint Typhoon Warning Center (JTWC) and Global Disaster Alert and Coordination System (GDACS) who release storm nodes and tracks (forecasted and actual), with wind buffers and classify the event according to the Saffir-Simpson Hurricane Wind Scale. For floods, the community is usually able to acquire unclassified data of the flood extent as identified from satellite imagery. Most often no water discharge hydrograph is available to classify the event into recurrence intervals simply because there is no gauging station, or the gauging station was unable to record the maximum discharge due to overtopping or flood damage. So, the question remains: How do we methodically turn a flooded area into classified areas of different gradations of impact? Here, we present a first approach towards developing a global applicable flood severity index. The flood severity index is set up such that it considers relatively easily obtainable physical parameters in a short period of time like: flood frequency (relating the current flood to historical events) and magnitude, as well as land cover, slope, and where available pre-event simulated flood depth. The scale includes categories ranging from very minor flooding to catastrophic flooding. We test and evaluate the postulated classification scheme against a set of past flood events. Once a severity category is determined, socio

  9. Source apportionment of ambient particle number concentrations in central Los Angeles using positive matrix factorization (PMF

    Directory of Open Access Journals (Sweden)

    M. H. Sowlat

    2016-04-01

    Full Text Available In this study, the positive matrix factorization (PMF receptor model (version 5.0 was used to identify and quantify major sources contributing to particulate matter (PM number concentrations, using PM number size distributions in the range of 13 nm to 10 µm combined with several auxiliary variables, including black carbon (BC, elemental and organic carbon (EC/OC, PM mass concentrations, gaseous pollutants, meteorological, and traffic counts data, collected for about 9 months between August 2014 and 2015 in central Los Angeles, CA. Several parameters, including particle number and volume size distribution profiles, profiles of auxiliary variables, contributions of different factors in different seasons to the total number concentrations, diurnal variations of each of the resolved factors in the cold and warm phases, weekday/weekend analysis for each of the resolved factors, and correlation between auxiliary variables and the relative contribution of each of the resolved factors, were used to identify PM sources. A six-factor solution was identified as the optimum for the aforementioned input data. The resolved factors comprised nucleation, traffic 1, traffic 2 (with a larger mode diameter than traffic 1 factor, urban background aerosol, secondary aerosol, and soil/road dust. Traffic sources (1 and 2 were the major contributor to PM number concentrations, collectively making up to above 60 % (60.8–68.4 % of the total number concentrations during the study period. Their contribution was also significantly higher in the cold phase compared to the warm phase. Nucleation was another major factor significantly contributing to the total number concentrations (an overall contribution of 17 %, ranging from 11.7 to 24 %, with a larger contribution during the warm phase than in the cold phase. The other identified factors were urban background aerosol, secondary aerosol, and soil/road dust, with relative contributions of approximately 12

  10. A comparison of PCA and PMF models for source identification of fugitive methane emissions

    Science.gov (United States)

    Assan, Sabina; Baudic, Alexia; Bsaibes, Sandy; Gros, Valerie; Ciais, Philippe; Staufer, Johannes; Robinson, Rod; Vogel, Felix

    2017-04-01

    Methane (CH_4) is a greenhouse gas with a global warming potential 28-32 times that of carbon dioxide (CO_2) on a 100 year period, and even greater on shorter timescales [Etminan, et al., 2016, Allen, 2014]. Thus, despite its relatively short life time and smaller emission quantities compared to CO_2, CH4 emissions contribute to approximately 20{%} of today's anthropogenic greenhouse gas warming [Kirschke et al., 2013]. Major anthropogenic sources include livestock (enteric fermentation), oil and gas production and distribution, landfills, and wastewater emissions [EPA, 2011]. Especially in densely populated areas multiple CH4 sources can be found in close vicinity. Thus, when measuring CH4 emissions at local scales it is necessary to distinguish between different CH4 source categories to effectively quantify the contribution of each sector and aid the implementation of greenhouse gas reduction strategies. To this end, source apportionment models can be used to aid the interpretation of spatial and temporal patterns in order to identify and characterise emission sources. The focus of this study is to evaluate two common linear receptor models, namely Principle Component Analysis (PCA) and Positive Matrix Factorisation (PMF) for CH4 source apportionment. The statistical models I will present combine continuous in-situ CH4 , C_2H_6, δ^1^3CH4 measured using a Cavity Ring Down Spectroscopy (CRDS) instrument [Assan et al. 2016] with volatile organic compound (VOC) observations performed using Gas Chromatography (GC) in order to explain the underlying variance of the data. The strengths and weaknesses of both models are identified for data collected in multi-source environments in the vicinity of four different types of sites; an agricultural farm with cattle, a natural gas compressor station, a wastewater treatment plant, and a pari-urban location in the Ile de France region impacted by various sources. To conclude, receptor model results to separate statistically the

  11. Source apportionment of the carcinogenic potential of polycyclic aromatic hydrocarbons (PAH) associated to airborne PM10 by a PMF model.

    Science.gov (United States)

    Callén, M S; Iturmendi, A; López, J M; Mastral, A M

    2014-02-01

    In order to perform a study of the carcinogenic potential of polycyclic aromatic hydrocarbons (PAH), benzo(a)pyrene equivalent (BaP-eq) concentration was calculated and modelled by a receptor model based on positive matrix factorization (PMF). Nineteen PAH associated to airborne PM10 of Zaragoza, Spain, were quantified during the sampling period 2001-2009 and used as potential variables by the PMF model. Afterwards, multiple linear regression analysis was used to quantify the potential sources of BaP-eq. Five sources were obtained as the optimal solution and vehicular emission was identified as the main carcinogenic source (35 %) followed by heavy-duty vehicles (28 %), light-oil combustion (18 %), natural gas (10 %) and coal combustion (9 %). Two of the most prevailing directions contributing to this carcinogenic character were the NE and N directions associated with a highway, industrial parks and a paper factory. The lifetime lung cancer risk exceeded the unit risk of 8.7 x 10(-5) per ng/m(3) BaP in both winter and autumn seasons and the most contributing source was the vehicular emission factor becoming an important issue in control strategies.

  12. PM10 source apportionment applying PMF and chemical tracer analysis to ship-borne measurements in the Western Mediterranean

    Science.gov (United States)

    Bove, M. C.; Brotto, P.; Calzolai, G.; Cassola, F.; Cavalli, F.; Fermo, P.; Hjorth, J.; Massabò, D.; Nava, S.; Piazzalunga, A.; Schembari, C.; Prati, P.

    2016-01-01

    A PM10 sampling campaign was carried out on board the cruise ship Costa Concordia during three weeks in summer 2011. The ship route was Civitavecchia-Savona-Barcelona-Palma de Mallorca-Malta (Valletta)-Palermo-Civitavecchia. The PM10 composition was measured and utilized to identify and characterize the main PM10 sources along the ship route through receptor modelling, making use of the Positive Matrix Factorization (PMF) algorithm. A particular attention was given to the emissions related to heavy fuel oil combustion by ships, which is known to be also an important source of secondary sulphate aerosol. Five aerosol sources were resolved by the PMF analysis. The primary contribution of ship emissions to PM10 turned out to be (12 ± 4)%, while secondary ammonium sulphate contributed by (35 ± 5)%. Approximately, 60% of the total sulphate was identified as secondary aerosol while about 20% was attributed to heavy oil combustion in ship engines. The measured concentrations of methanesulphonic acid (MSA) indicated a relevant contribution to the observed sulphate loading by biogenic sulphate, formed by the atmospheric oxidation of dimethyl sulphide (DMS) emitted by marine phytoplankton.

  13. Characterising Record Flooding in the United Kingdom

    Science.gov (United States)

    Cox, A.; Bates, P. D.; Smith, J. A.

    2017-12-01

    Though the most notable floods in history have been carefully explained, there remains a lack of literature that explores the nature of record floods as a whole in the United Kingdom. We characterise the seasonality, statistical and spatial distribution, and meteorological causes of peak river flows for 521 gauging stations spread across the British Isles. We use annual maximum data from the National River Flow Archive, catchment descriptors from the Flood Estimation Handbook, and historical records of large floods. What we aim to find is in what ways, if any, the record flood for a station is different from more 'typical' floods. For each station, we calculate two indices: the seasonal anomaly and the flood index. Broadly, the seasonal anomaly is the degree to which a station's record flood happens at a different time of year compared to typical floods at that site, whilst the flood index is a station's record flood discharge divided by the discharge of the 1-in-10-year return period event. We find that while annual maximum peaks are dominated by winter frontal rainfall, record floods are disproportionately caused by summer convective rainfall. This analysis also shows that the larger the seasonal anomaly, the higher the flood index. Additionally, stations across the country have record floods that occur in the summer with no notable spatial pattern, yet the most seasonally anomalous record events are concentrated around the south and west of the British Isles. Catchment descriptors tell us little about the flood index at a particular station, but generally areas with lower mean annual precipitation have a higher flood index. The inclusion of case studies from recent and historical examples of notable floods across the UK supplements our analysis and gives insight into how typical these events are, both statistically and meteorologically. Ultimately, record floods in general happen at relatively unexpected times and with unpredictable magnitudes, which is a

  14. Flood protection of Crystal River Unit 3 Nuclear Plant

    International Nuclear Information System (INIS)

    Noble, R.M.; Simpson, B.

    1975-01-01

    To satisfy U.S. Atomic Energy Commission (AEC) safety criteria, a required evaluation of the worst site-related flood is performed for the Crystal River Plant, located on the Gulf Coast of Florida, the probable maximum stillwater flood levels are likely to be a result of the probable maximum hurricane. Flood protection requirements for the Crystal River Plant are determined by considering the most severe combination of probable maximum hurricane parameters for the Gulf Coast Region. These parameters are used as input to a model of hurricane surge generation and attendant wave activity in order to determine the maximum flood levels at the Crystal River Plant. 4 refs

  15. Tracking polychlorinated biphenyls (PCBs) congener patterns in Newark Bay surface sediment using principal component analysis (PCA) and positive matrix factorization (PMF).

    Science.gov (United States)

    Saba, Tarek; Su, Steave

    2013-09-15

    PCB congener data for Newark Bay surface sediments were analyzed using PCA and PMF, and relationships between the outcomes from these two techniques were explored. The PCA scores plot separated the Lower Passaic River Mouth samples from North Newark Bay, thus indicating dissimilarity. Although PCA was able to identify subareas in the Bay system with specific PCB congener patterns (e.g., higher chlorinated congeners in Elizabeth River), further conclusions reading potential PCB source profiles or potential upland source areas were not clear for the PCA scores plot. PMF identified five source factors, and explained the Bay sample congener profiles as a mix of these Factors. This PMF solution was equivalent to (1) defining an envelope that encompasses all samples on the PCA scores plot, (2) defining source factors that plot on that envelope, and (3) explaining the congener profile for each Bay sediment sample (inside the scores plot envelope) as a mix of factors. PMF analysis allowed identifying characteristic features in the source factor congener distributions that allowed tracking of source factors to shoreline areas where PCB inputs to the Bay may have originated. The combined analysis from PCA and PMF showed that direct discharges to the Bay are likely the dominant sources of PCBs to the sediment. Review of historical upland activities and regulatory files will be needed, in addition to the PCA and PMF analysis, to fully reconstruct the history of operations and PCB releases around the Newark Bay area that impacted the Bay sediment. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Source apportionment of particles at Station Nord, North East Greenland during 2008–2010 using COPREM and PMF analysis

    DEFF Research Database (Denmark)

    Nguyen, Quynh; Skov, Henrik; Sørensen, Lise Lotte

    2013-01-01

    In order to develop strategies for controlling and reducing Arctic air pollution, there is a need to understand the basic mechanisms for determining the fate of air pollution in the Arctic. Sources of atmospheric particles at Station Nord (81° 36' N, 16° 40' W) in North East Greenland were...... evaluated for a two-year period from March 2008 to February 2010. Source apportionment using Positive Matrix Factorization (PMF) and COnstrained Physical REceptor Model (COPREM) was based on measurements of black carbon, elements (Al, Si, S, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, As, Se, Br, Rb, Sr, Zr...... origins. Another anthropogenic source was characterised by high concentrations of Pb and As, which has been historically referred to as a Combustion source at Station Nord. The impacts of large-scale industry in Siberia, Russia were evident through high Cu concentrations in both the Combustion source...

  17. Source apportionment of heavy metals in agricultural soil based on PMF: A case study in Hexi Corridor, northwest China.

    Science.gov (United States)

    Guan, Qingyu; Wang, Feifei; Xu, Chuanqi; Pan, Ninghui; Lin, Jinkuo; Zhao, Rui; Yang, Yanyan; Luo, Haiping

    2018-02-01

    Hexi Corridor is the most important base of commodity grain and producing area for cash crops. However, the rapid development of agriculture and industry has inevitably led to heavy metal contamination in the soils. Multivariate statistical analysis, GIS-based geostatistical methods and Positive Matrix Factorization (PMF) receptor modeling techniques were used to understand the levels of heavy metals and their source apportionment for agricultural soil in Hexi Corridor. The results showed that the average concentrations of Cr, Cu, Ni, Pb and Zn were lower than the secondary standard of soil environmental quality; however, the concentrations of eight metals (Cr, Cu, Mn, Ni, Pb, Ti, V and Zn) were higher than background values, and their corresponding enrichment factor values were significantly greater than 1. Different degrees of heavy metal pollution occurred in the agricultural soils; specifically, Ni had the most potential for impacting human health. The results from the multivariate statistical analysis and GIS-based geostatistical methods indicated both natural sources (Co and W) and anthropogenic sources (Cr, Cu, Mn, Ni, Pb, Ti, V and Zn). To better identify pollution sources of heavy metals in the agricultural soils, the PMF model was applied. Further source apportionment revealed that enrichments of Pb and Zn were attributed to traffic sources; Cr and Ni were closely related to industrial activities, including mining, smelting, coal combustion, iron and steel production and metal processing; Zn and Cu originated from agricultural activities; and V, Ti and Mn were derived from oil- and coal-related activities. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. A new generic plant growth model framework (PMF): Simulating distributed dynamic interaction of biomass production and its interaction with water and nutrients fluxes

    Science.gov (United States)

    Multsch, Sebastian; Kraft, Philipp; Frede, Hans-Georg; Breuer, Lutz

    2010-05-01

    about changing boundary conditions. The crop model concept refers to two main elements. A plant model, which represents an abstract network of plant organs and processes and a process library, which holds mathematical solutions for the growth processes. Growth processes were mainly taken from existing, well known crop models such as SUCROS and CERES. The crop specific properties of root architecture are described based on a maximum rooting depth and a vertical growth rate. The biomass distribution depends on an interactive allocation process due to the soil layers with a daily time step. In order to show the performance and capabilities of PMF, the model is coupled with the Catchment Modeling Framework (CMF) and the simple nitrogen mineralization model DeComp. The main feature of the integrated model set up is the interaction between root growth, water uptake and nitrogen supply of the soil. We show a virtual case study on the hillslope scale and spatially dependence of water and nitrogen stress based on topographic position and seasonal development.

  19. Identification and classification of Serbia's historic floods

    Directory of Open Access Journals (Sweden)

    Prohaska Stevan

    2009-01-01

    Full Text Available River flooding in Serbia is a natural phenomenon which largely exceeds the scope of water management and hydraulic engineering, and has considerable impact on the development of Serbian society. Today, the importance and value of areas threatened by floods are among the key considerations of sustainable development. As a result, flood protection techniques and procedures need to be continually refined and updated, following innovations in the fields of science and technology. Knowledge of high flows is key for sizing hydraulic structures and for gauging the cost-effectiveness and safety of the component structures of flood protection systems. However, sizing of hydraulic structures based on computed high flows does not ensure absolute safety; there is a residual flood risk and a risk of structural failure, if a flood exceeds computed levels. In hydrological practice, such floods are often referred to as historic/loads. The goal of this paper is to present a calculation procedure for the objective identification of historic floods, using long, multiple-year series of data on high flows of natural watercourses in Serbia. At its current stage of development, the calculation procedure is based on maximum annual discharges recorded at key monitoring stations of the Hydro-Meteorological Service of Serbia (HMS Serbia. When applied, the procedure results in the identification of specific historic maximum stages/floods (if any at all gauge sites included in the analysis. The probabilistic theory is then applied to assess the statistical significance of each identified historic flood and to classify the historic flood, as appropriate. At the end of the paper, the results of the applied methodology are shown in tabular and graphic form for various Serbian rivers. All identified historic floods are ranked based on their probability of occurrence (i.e., return period.

  20. Source apportionment of particles at Station Nord, North East Greenland during 2008–2010 using COPREM and PMF analysis

    Directory of Open Access Journals (Sweden)

    Q. T. Nguyen

    2013-01-01

    Full Text Available In order to develop strategies for controlling and reducing Arctic air pollution, there is a need to understand the basic mechanisms for determining the fate of air pollution in the Arctic. Sources of atmospheric particles at Station Nord (81° 36' N, 16° 40' W in North East Greenland were evaluated for a two-year period from March 2008 to February 2010. Source apportionment using Positive Matrix Factorization (PMF and COnstrained Physical REceptor Model (COPREM was based on measurements of black carbon, elements (Al, Si, S, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, As, Se, Br, Rb, Sr, Zr, Pb and inorganic ions (SO2, SO42−, Na+, NH4+, NO3, Cl2−. In general, source apportionment results by PMF and COPREM showed good agreement. Five sources adequately explained the measurements, which included a Marine and a Soil source of natural origin and three additional anthropogenic sources, which were all influenced by metal industries. One anthropogenic source was dominated by Zn of which air mass back trajectories using the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT model suggested a Canadian Arctic origin, despite certain influences from Southern and Eastern origins. Another anthropogenic source was characterised by high concentrations of Pb and As, which has been historically referred to as a Combustion source at Station Nord. The impacts of large-scale industry in Siberia, Russia were evident through high Cu concentrations in both the Combustion source and an additional Cu/Ni source.

    Br correlated well with the anthropogenic species S and Pb though the elements are unlikely to have a common origin. More likely, sulphuric acid aerosols serve as transport containers for Br species of marine origin. Of particular relevance to climate, sources of black carbon were identified to be

  1. Flood Hazard Mapping by Applying Fuzzy TOPSIS Method

    Science.gov (United States)

    Han, K. Y.; Lee, J. Y.; Keum, H.; Kim, B. J.; Kim, T. H.

    2017-12-01

    There are lots of technical methods to integrate various factors for flood hazard mapping. The purpose of this study is to suggest the methodology of integrated flood hazard mapping using MCDM(Multi Criteria Decision Making). MCDM problems involve a set of alternatives that are evaluated on the basis of conflicting and incommensurate criteria. In this study, to apply MCDM to assessing flood risk, maximum flood depth, maximum velocity, and maximum travel time are considered as criterion, and each applied elements are considered as alternatives. The scheme to find the efficient alternative closest to a ideal value is appropriate way to assess flood risk of a lot of element units(alternatives) based on various flood indices. Therefore, TOPSIS which is most commonly used MCDM scheme is adopted to create flood hazard map. The indices for flood hazard mapping(maximum flood depth, maximum velocity, and maximum travel time) have uncertainty concerning simulation results due to various values according to flood scenario and topographical condition. These kind of ambiguity of indices can cause uncertainty of flood hazard map. To consider ambiguity and uncertainty of criterion, fuzzy logic is introduced which is able to handle ambiguous expression. In this paper, we made Flood Hazard Map according to levee breach overflow using the Fuzzy TOPSIS Technique. We confirmed the areas where the highest grade of hazard was recorded through the drawn-up integrated flood hazard map, and then produced flood hazard map can be compared them with those indicated in the existing flood risk maps. Also, we expect that if we can apply the flood hazard map methodology suggested in this paper even to manufacturing the current flood risk maps, we will be able to make a new flood hazard map to even consider the priorities for hazard areas, including more varied and important information than ever before. Keywords : Flood hazard map; levee break analysis; 2D analysis; MCDM; Fuzzy TOPSIS

  2. 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.

  3. Floods and droughts on the lower Vistula

    Directory of Open Access Journals (Sweden)

    Marzenna Sztobryn

    2013-06-01

    Full Text Available The study analyses floods and droughts on the lower Vistula based on the data (water levels and flow rates recorded in stations of the Institute of Meteorology and Water Management – National Research Institute (IMGW-PIB in Warsaw, Kępa Polska, Toruń and Tczew. It also includes the causes of flooding and drought in the lower Vistula with the hydrological characteristics from the years 1951–2010. The variability in maximum and minimum annual and monthly flow rates has been analysed for the aforementioned period as well. In addition, the authors have analysed changes in the shape of the flood wave after passing through the reservoir and cascade in Włocławek based on the hydrograph of May and June 2010. It has been found that the flood wave is flattened and extended. This phenomenon is favourable from the point of view of flood actions.

  4. Water quality assessment and apportionment of pollution sources using APCS-MLR and PMF receptor modeling techniques in three major rivers of South Florida.

    Science.gov (United States)

    Haji Gholizadeh, Mohammad; Melesse, Assefa M; Reddi, Lakshmi

    2016-10-01

    In this study, principal component analysis (PCA), factor analysis (FA), and the absolute principal component score-multiple linear regression (APCS-MLR) receptor modeling technique were used to assess the water quality and identify and quantify the potential pollution sources affecting the water quality of three major rivers of South Florida. For this purpose, 15years (2000-2014) dataset of 12 water quality variables covering 16 monitoring stations, and approximately 35,000 observations was used. The PCA/FA method identified five and four potential pollution sources in wet and dry seasons, respectively, and the effective mechanisms, rules and causes were explained. The APCS-MLR apportioned their contributions to each water quality variable. Results showed that the point source pollution discharges from anthropogenic factors due to the discharge of agriculture waste and domestic and industrial wastewater were the major sources of river water contamination. Also, the studied variables were categorized into three groups of nutrients (total kjeldahl nitrogen, total phosphorus, total phosphate, and ammonia-N), water murkiness conducive parameters (total suspended solids, turbidity, and chlorophyll-a), and salt ions (magnesium, chloride, and sodium), and average contributions of different potential pollution sources to these categories were considered separately. The data matrix was also subjected to PMF receptor model using the EPA PMF-5.0 program and the two-way model described was performed for the PMF analyses. Comparison of the obtained results of PMF and APCS-MLR models showed that there were some significant differences in estimated contribution for each potential pollution source, especially in the wet season. Eventually, it was concluded that the APCS-MLR receptor modeling approach appears to be more physically plausible for the current study. It is believed that the results of apportionment could be very useful to the local authorities for the control and

  5. Texas floods of 1940

    Science.gov (United States)

    Breeding, Seth D.

    1948-01-01

    Floods occurred in Texas during, June, July, and November 1940 that exceeded known stages on many small streams and at a few places on the larger streams. Stages at several stream-gaging stations exceeded the maximum known at those places since the collection of daily records began. A storm, haying its axis generally on a north-south line from Cameron to Victoria and extending across the Brazos, Colorado, Lavaca, and Guadalupe River Basins, caused heavy rainfall over a large part of south-central Texas. The maximum recorded rain of 22.7 inches for the 2-day period June 29-30 occurred at Engle. Of this amount, 17.5 inches fell in the 12-hour period between 8 p.m. June 29, and 8 a.m. June 30. Light rains fell at a number of places on June 28, and additional light rains fell at many places within the area from July 1 to 4. During the period June 28 to July 4 more than 20 inches of rain fell over an area of 300 square miles, more than 15 inches over 1,920 square miles, and more than 10 inches over 5,100 square miles. The average annual rainfall for the area experiencing the heaviest rainfall during this storm is about 35 inches. Farming is largely confined to the fertile flood plains in much of the area subjected to the record-breaking floods in June and July. Therefore these floods, coming at the height of the growing season, caused severe losses to crops. Much damage was done also to highways and railways. The city of Hallettsville suffered the greatest damage of any urban area. The Lavaca River at that place reached a stage 8 feet higher than ever known before, drowned several people, destroyed many homes, and submerged almost the entire business district. The maximum discharge there was 93,100 second-feet from a drainage area of 101 square miles. Dry Creek near Smithville produced a maximum discharge of 1,879 second-feet from an area of 1.48 square miles and a runoff of 11.3 inches in a 2-day period from a rainfall of 19.5 inches. The area in the Colorado River

  6. Effect of catchment properties and flood generation regime on copula selection for bivariate flood frequency analysis

    Science.gov (United States)

    Filipova, Valeriya; Lawrence, Deborah; Klempe, Harald

    2018-02-01

    Applying copula-based bivariate flood frequency analysis is advantageous because the results provide information on both the flood peak and volume. More data are, however, required for such an analysis, and it is often the case that only data series with a limited record length are available. To overcome this issue of limited record length, data regarding climatic and geomorphological properties can be used to complement statistical methods. In this paper, we present a study of 27 catchments located throughout Norway, in which we assess whether catchment properties, flood generation processes and flood regime have an effect on the correlation between flood peak and volume and, in turn, on the selection of copulas. To achieve this, the annual maximum flood events were first classified into events generated primarily by rainfall, snowmelt or a combination of these. The catchments were then classified into flood regime, depending on the predominant flood generation process producing the annual maximum flood events. A contingency table and Fisher's exact test were used to determine the factors that affect the selection of copulas in the study area. The results show that the two-parameter copulas BB1 and BB7 are more commonly selected in catchments with high steepness, high mean annual runoff and rainfall flood regime. These findings suggest that in these types of catchments, the dependence structure between flood peak and volume is more complex and cannot be modeled effectively using a one-parameter copula. The results illustrate that by relating copula types to flood regime and catchment properties, additional information can be supplied for selecting copulas in catchments with limited data.

  7. Flood-rich and flood-poor periods in Spain in 1942-2009

    Science.gov (United States)

    Mediero, Luis; Santillán, David; Garrote, Luis

    2016-04-01

    Several studies to detect trends in flood series at either national or trans-national scales have been conducted. Mediero et al. (2015) studied flood trends by using the longest streamflow records available in Europe. They found a decreasing trend in the Atlantic, Continental and Scandinavian regions. More specifically, Mediero et al. (2014) found a general decreasing trend in flood series in Spain in the period 1959-2009. Trends in flood series are usually detected by the Mann-Kendall test applied to a given period. However, the result of the Mann-Kendall test can change in terms of the starting and ending year of the series. Flood oscillations can occur and flood-rich and flood-poor periods could condition the results, especially when they are located at the beginning or end of the series. A methodology to identify statistically significant flood-rich and flood-poor periods is developed, based on the comparison between the expected sampling variability of floods when stationarity is assumed and the observed variability of floods in a given series. The methodology is applied to the longest series of annual maximum floods, peaks over threshold and counts of annual occurrences in peaks over threshold series observed in Spain in the period 1942-2009. A flood-rich period in 1950-1970 and a flood-poor period in 1970-1990 are identified in most of the selected sites. The generalised decreasing trend in flood series found by Mediero et al. (2014) could be explained by a flood-rich period placed at the beginning of the series and a flood-poor period located at the end of the series. References: Mediero, L., Kjeldsen, T.R., Macdonald, N., Kohnova, S., Merz, B., Vorogushyn, S., Wilson, D., Alburquerque, T., Blöschl, G., Bogdanowicz, E., Castellarin, A., Hall, J., Kobold, M., Kriauciuniene, J., Lang, M., Madsen, H., Onuşluel Gül, G., Perdigão, R.A.P., Roald, L.A., Salinas, J.L., Toumazis, A.D., Veijalainen, N., Óðinn Þórarinsson. Identification of coherent flood

  8. Flooding and Schools

    Science.gov (United States)

    National Clearinghouse for Educational Facilities, 2011

    2011-01-01

    According to the Federal Emergency Management Agency, flooding is the nation's most common natural disaster. Some floods develop slowly during an extended period of rain or in a warming trend following a heavy snow. Flash floods can occur quickly, without any visible sign of rain. Catastrophic floods are associated with burst dams and levees,…

  9. Approximate maximum parsimony and ancestral maximum likelihood.

    Science.gov (United States)

    Alon, Noga; Chor, Benny; Pardi, Fabio; Rapoport, Anat

    2010-01-01

    We explore the maximum parsimony (MP) and ancestral maximum likelihood (AML) criteria in phylogenetic tree reconstruction. Both problems are NP-hard, so we seek approximate solutions. We formulate the two problems as Steiner tree problems under appropriate distances. The gist of our approach is the succinct characterization of Steiner trees for a small number of leaves for the two distances. This enables the use of known Steiner tree approximation algorithms. The approach leads to a 16/9 approximation ratio for AML and asymptotically to a 1.55 approximation ratio for MP.

  10. 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

    -scale view of the extent and depth of possible riverine flood events several days in advance by linking forecast river flow from a hydrological model to a global flood risk map. The Monitoring component provides a similar local-scale view of a flood inundation extent but in near real time, as an event unfolds, by combining the global flood risk map with observed river gauge telemetry. Immediately following an event, the maximum extent of the flood is also generated. Users of Flood Foresight will be able to receive current and forecast flood extents and depth information via API into their own GIS or analytics software. The set of tools is currently operational for the UK and Europe; the methods presented can be applied globally, allowing provision of service to any country or region. This project was supported by InnovateUK under the Solving Business Problems with Environmental Data competition.

  11. Maximum permissible dose

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    This chapter presents a historic overview of the establishment of radiation guidelines by various national and international agencies. The use of maximum permissible dose and maximum permissible body burden limits to derive working standards is discussed

  12. Flood frequency analysis of historical flood data under stationary and non-stationary modelling

    Science.gov (United States)

    Machado, M. J.; Botero, B. A.; López, J.; Francés, F.; Díez-Herrero, A.; Benito, G.

    2015-06-01

    Historical records are an important source of information on extreme and rare floods and fundamental to establish a reliable flood return frequency. The use of long historical records for flood frequency analysis brings in the question of flood stationarity, since climatic and land-use conditions can affect the relevance of past flooding as a predictor of future flooding. In this paper, a detailed 400 yr flood record from the Tagus River in Aranjuez (central Spain) was analysed under stationary and non-stationary flood frequency approaches, to assess their contribution within hazard studies. Historical flood records in Aranjuez were obtained from documents (Proceedings of the City Council, diaries, chronicles, memoirs, etc.), epigraphic marks, and indirect historical sources and reports. The water levels associated with different floods (derived from descriptions or epigraphic marks) were computed into discharge values using a one-dimensional hydraulic model. Secular variations in flood magnitude and frequency, found to respond to climate and environmental drivers, showed a good correlation between high values of historical flood discharges and a negative mode of the North Atlantic Oscillation (NAO) index. Over the systematic gauge record (1913-2008), an abrupt change on flood magnitude was produced in 1957 due to constructions of three major reservoirs in the Tagus headwaters (Bolarque, Entrepeñas and Buendia) controlling 80% of the watershed surface draining to Aranjuez. Two different models were used for the flood frequency analysis: (a) a stationary model estimating statistical distributions incorporating imprecise and categorical data based on maximum likelihood estimators, and (b) a time-varying model based on "generalized additive models for location, scale and shape" (GAMLSS) modelling, which incorporates external covariates related to climate variability (NAO index) and catchment hydrology factors (in this paper a reservoir index; RI). Flood frequency

  13. Changes in the timing and magnitude of floods in Canada

    International Nuclear Information System (INIS)

    Cunderlik, J.M.; Ouarda, T.B.M.J.

    2008-01-01

    It is expected that the global climate change will have significant impacts on the regime of hydrologic extremes. An increase in both the frequency and magnitude of hydrologic extremes is anticipated in the near future. As a consequence, the design and operation of water resource systems will have to adapt to the changing regime of hydrologic extremes. This study explores trends in the timing and magnitude of floods in natural streamflow gauging stations in Canada. The seasonality of floods is analyzed and the selected streamflow stations grouped into five flood seasonality regions. A common 30-year long observation period from 1974 to 2003 is used in the analysis to eliminate the effect of hydro-climatic variability in the timing and magnitude of floods resulting from different observation periods. The timing of floods is described in terms of directional statistics. A method is developed for analyzing trends in directional dates of flood occurrence that is not affected by the choice of zero direction. The magnitude of floods is analyzed by the annual maximum and peak-over-threshold methods. Trends in the timing and magnitude of floods are identified in each flood seasonality region using the Mann-Kendall nonparametric test, with a modification for auto-correlated data. The results show a good correspondence between the identified flood seasonality regions and the main terrestrial zones in Canada. Significant changes in the timing and magnitude of floods are found in the flood seasonality regions. (author)

  14. Precipitation Thresholds for Triggering Floods in the Corgo Basin, Portugal

    Directory of Open Access Journals (Sweden)

    Mónica Santos

    2016-08-01

    Full Text Available Thresholds based on critical combinations of amount/duration of precipitation and flood events were estimated for the Corgo hydrographic basin, in northern Portugal. Thirty-one flood events in the Corgo basin were identified between 1865 and 2011 from a database of hydrometeorological disasters in Portugal. The minimum, maximum, and pre-warning thresholds that define the boundaries for flood occurrence were determined. The results show that the ratio between the total number of floods and precipitation events exceeding the minimum threshold denotes a relatively low probability of successful forecasting. This result may be due to the reduced number of flooding events in the floods database, which only include floods that caused damage as reported by the media. The estimated maximum threshold is not adequate for use in floods, since the majority of true positives are below this limit. However, and more interestingly, the retrospective verification of the estimated thresholds suggests that the minimum and pre-warning thresholds are well adjusted. Therefore, the application of these precipitation thresholds may contribute to minimize possible situations of pre-crisis or immediate crisis by reducing the flood consequences and the resources involved in emergency response to flood events.

  15. Performance of regional flood frequency analysis methods in ...

    African Journals Online (AJOL)

    2015-04-03

    Apr 3, 2015 ... Available on website http://www.wrc.org.za. ISSN 1816-7950 ... Estimates of design floods are required for the design of hydraulic structures and to quantify the risk of failure of the ... performance when compared to design floods estimated from the annual maximum series extracted from the observed data.

  16. Flood simulation model using XP-SWMM along Terengganu River ...

    African Journals Online (AJOL)

    Malaysia is one of the tropical countries in the world with heavy rainfall throughout the year and floods are the most common disaster in Malaysia. Flood simulation model was carried out along Terengganu River for dry and rainy seasons. The result of the simulation shows the water level reached its maximum level at the 1st ...

  17. Development of Positive Matrix Factorization Model (PMF) to Annual Study of the PM2.5 Organic Composition in ChapinerIa

    International Nuclear Information System (INIS)

    Pindado, O.; Perez, R. M.; Garcia, S.

    2013-01-01

    The Positive Matrix Factorization (PMF) application to a set of PM2.5 data collected in a rural area of Madrid for a period of 1 year has been developed. Results has let describing the particulate faction of atmospheric aerosol collected in Chapineria according to 7 factor, among them fossil fuel combustion by traffic, wax plants, primary emissions of organic carbon, crustal material, and secondary organic aerosol. Five of these factors are related to primary particles; meanwhile only one factor has been associated to secondary particles. Finally, a factor has not been associated to any known source of particulate matter. (Author)

  18. Source apportionment of PM2.5 at a regional background site in North China using PMF linked with radiocarbon analysis: insight into the contribution of biomass burning

    Directory of Open Access Journals (Sweden)

    Z. Zong

    2016-09-01

    Full Text Available Source apportionment of fine particles (PM2.5 at a background site in North China in the winter of 2014 was done using statistical analysis, radiocarbon (14C measurement and positive matrix factorization (PMF modeling. Results showed that the concentration of PM2.5 was 77.6 ± 59.3 µg m−3, of which sulfate (SO42− concentration was the highest, followed by nitrate (NO3−, organic carbon (OC, elemental carbon (EC and ammonium (NH4+. As demonstrated by backward trajectory, more than half of the air masses during the sampling period were from the Beijing–Tianjin–Hebei (BTH region, followed by Mongolia and the Shandong Peninsula. Cluster analysis of chemical species suggested an obvious signal of biomass burning in the PM2.5 from the Shandong Peninsula, while the PM2.5 from the BTH region showed a vehicle emission pattern. This finding was further confirmed by the 14C measurement of OC and EC in two merged samples. The 14C result indicated that biogenic and biomass burning emission contributed 59 ± 4 and 52 ± 2 % to OC and EC concentrations, respectively, when air masses originated from the Shandong Peninsula, while the contributions fell to 46 ± 4 and 38 ± 1 %, respectively, when the prevailing wind changed and came from the BTH region. The minimum deviation between source apportionment results from PMF and 14C measurement was adopted as the optimal choice of the model exercises. Here, two minor overestimates with the same range (3 % implied that the PMF result provided a reasonable source apportionment of the regional PM2.5 in this study. Based on the PMF modeling, eight sources were identified; of these, coal combustion, biomass burning and vehicle emission were the main contributors of PM2.5, accounting for 29.6, 19.3 and 15.9 %, respectively. Compared with overall source apportionment, the contributions of vehicle emission, mineral dust, coal combustion and biomass burning increased when air masses

  19. 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...

  20. Flood Hazard Boundaries

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The National Flood Hazard Layer (NFHL) data incorporates all Digital Flood Insurance Rate Map(DFIRM) databases published by FEMA, and any Letters Of Map Revision...

  1. Base Flood Elevation

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The National Flood Hazard Layer (NFHL) data incorporates all Digital Flood Insurance Rate Map(DFIRM) databases published by FEMA, and any Letters Of Map Revision...

  2. Flood Risk Regional Flood Defences : Technical report

    NARCIS (Netherlands)

    Kok, M.; Jonkman, S.N.; Lendering, K.T.

    2015-01-01

    Historically the Netherlands have always had to deal with the threat of flooding, both from the rivers and the sea as well as from heavy rainfall. The country consists of a large amount of polders, which are low lying areas of land protected from flooding by embankments. These polders require an

  3. Flood Risk Characterization for the Eastern United States

    Science.gov (United States)

    Villarini, G.; Smith, J. A.; Ntelekos, A. A.

    2009-04-01

    Tropical cyclones landfalling in the eastern United States pose a major risk for insured property and can lead to extensive damage through storm surge flooding, inland flooding or extreme windspeeds. Current hurricane cat-models do not include calculations of inland flooding from the outer rainfall bands of tropical cyclones but the issue is becoming increasingly important for commercial insurance risk assessment. The results of this study could be used to feed into the next generation of hurricane cat-models and assist in the calculation of damages from inland hurricane flood damage. Annual maximum peak discharge records from more than 400 stations in the eastern United States with at least 75 years of record to examine the role of landfalling tropical cyclones in controlling the upper tail of inland flood risk for the eastern United States. In addition to examining tropical cyclone inland flood risk at specific locations, the spatial extent of extreme flooding from lanfalling tropical cyclones is analyzed. Analyses of temporal trends and abrupt changes in the mean and variance of annual flood peaks are performed. Change-point analysis is performed using the non-parametric Pettitt test. Two non-parametric (Mann-Kendall and Spearman) tests and one parametric (Pearson) test are applied to detect the presence of temporal trends. Flood risk characterization centers on assessments of the spatial variation in "upper tail" properties of annual flood peak distributions. The modeling framework for flood frequency analysis is provided by the Generalized Additive Models for Location Scale and Shape (GAMLSS).

  4. Climate change effects on lowland stream flood regimes and riparian rich fen vegetation communities in Denmark

    DEFF Research Database (Denmark)

    Thodsen, Hans; Baattrup-Pedersen, Annette; Andersen, Hans Estrup

    2016-01-01

    continued through the two scenario periods, i.e. 2035-2065 and 2070-2099. We found concomitant increases in flood levels and flood frequencies. Flood levels and frequencies increased both at sites where the maximum water level was governed directly by river water runoff and where it was governed by river...

  5. Estimation of the Relative Severity of Floods in Small Ungauged Catchments for Preliminary Observations on Flash Flood Preparedness: A Case Study in Korea

    Science.gov (United States)

    Kim, Eung Seok; Choi, Hyun Il

    2012-01-01

    An increase in the occurrence of sudden local flooding of great volume and short duration has caused significant danger and loss of life and property in Korea as well as many other parts of the World. Since such floods usually accompanied by rapid runoff and debris flow rise quite quickly with little or no advance warning to prevent flood damage, this study presents a new flash flood indexing methodology to promptly provide preliminary observations regarding emergency preparedness and response to flash flood disasters in small ungauged catchments. Flood runoff hydrographs are generated from a rainfall-runoff model for the annual maximum rainfall series of long-term observed data in the two selected small ungauged catchments. The relative flood severity factors quantifying characteristics of flood runoff hydrographs are standardized by the highest recorded maximum value, and then averaged to obtain the flash flood index only for flash flood events in each study catchment. It is expected that the regression equations between the proposed flash flood index and rainfall characteristics can provide the basis database of the preliminary information for forecasting the local flood severity in order to facilitate flash flood preparedness in small ungauged catchments. PMID:22690208

  6. 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

  7. The June 2013 flood in the Upper Danube Basin, and comparisons with the 2002, 1954 and 1899 floods

    Science.gov (United States)

    Blöschl, G.; Nester, T.; Komma, J.; Parajka, J.; Perdigão, R. A. P.

    2013-12-01

    The June 2013 flood in the Upper Danube Basin was one of the largest floods in the past two centuries. An atmospheric blocking situation produced precipitation exceeding 300 mm over four days at the northern rim of the Alps. The high precipitation, along with high antecedent soil moisture, gave rise to extreme flood discharges in a number of tributaries including the Tiroler Ache, Saalach, Salzach and Inn. Runoff coefficients ranged from 0.2 in the Bavarian lowlands to 0.6 in the Alpine areas in Austria. Snowfall at high altitudes (above about 1600 m a.s.l.) reduced the runoff volume produced. Precipitation was distributed over two blocks separated by a few hours, which resulted in a single peak, long-duration flood wave at the Inn and Danube. At the confluence of the Bavarian Danube and the Inn, the small time lag between the two flood waves exacerbated the downstream flood at the Danube. Because of the long duration and less inundation, there was less flood peak attenuation along the Austrian Danube reach than for the August 2002 flood. Maximum flood discharges of the Danube at Vienna were about 11 000 m3 s-1, as compared to 10 300, 9600 and 10 500 m3 s-1 in 2002, 1954 and 1899, respectively. This paper reviews the meteorological and hydrological characteristics of the event as compared to the 2002, 1954 and 1899 floods, and discusses the implications for hydrological research and flood risk management.

  8. Maximum Acceleration Recording Circuit

    Science.gov (United States)

    Bozeman, Richard J., Jr.

    1995-01-01

    Coarsely digitized maximum levels recorded in blown fuses. Circuit feeds power to accelerometer and makes nonvolatile record of maximum level to which output of accelerometer rises during measurement interval. In comparison with inertia-type single-preset-trip-point mechanical maximum-acceleration-recording devices, circuit weighs less, occupies less space, and records accelerations within narrower bands of uncertainty. In comparison with prior electronic data-acquisition systems designed for same purpose, circuit simpler, less bulky, consumes less power, costs and analysis of data recorded in magnetic or electronic memory devices. Circuit used, for example, to record accelerations to which commodities subjected during transportation on trucks.

  9. Urban pluvial flood prediction

    DEFF Research Database (Denmark)

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

    2016-01-01

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

  10. Maximum Quantum Entropy Method

    OpenAIRE

    Sim, Jae-Hoon; Han, Myung Joon

    2018-01-01

    Maximum entropy method for analytic continuation is extended by introducing quantum relative entropy. This new method is formulated in terms of matrix-valued functions and therefore invariant under arbitrary unitary transformation of input matrix. As a result, the continuation of off-diagonal elements becomes straightforward. Without introducing any further ambiguity, the Bayesian probabilistic interpretation is maintained just as in the conventional maximum entropy method. The applications o...

  11. Maximum power demand cost

    International Nuclear Information System (INIS)

    Biondi, L.

    1998-01-01

    The charging for a service is a supplier's remuneration for the expenses incurred in providing it. There are currently two charges for electricity: consumption and maximum demand. While no problem arises about the former, the issue is more complicated for the latter and the analysis in this article tends to show that the annual charge for maximum demand arbitrarily discriminates among consumer groups, to the disadvantage of some [it

  12. FLOOD MENACE IN KADUNA METROPOLIS: IMPACTS ...

    African Journals Online (AJOL)

    Dr A.B.Ahmed

    damage, causes of flooding, human response to flooding and severity of ... from moving out. Source of ... Man responds to flood hazards through adjustment, flood abatement ... action to minimize or ameliorate flood hazards; flood abatement.

  13. Real-time flood extent maps based on social media

    Science.gov (United States)

    Eilander, Dirk; van Loenen, Arnejan; Roskam, Ruud; Wagemaker, Jurjen

    2015-04-01

    During a flood event it is often difficult to get accurate information about the flood extent and the people affected. This information is very important for disaster risk reduction management and crisis relief organizations. In the post flood phase, information about the flood extent is needed for damage estimation and calibrating hydrodynamic models. Currently, flood extent maps are derived from a few sources such as satellite images, areal images and post-flooding flood marks. However, getting accurate real-time or maximum flood extent maps remains difficult. With the rise of social media, we now have a new source of information with large numbers of observations. In the city of Jakarta, Indonesia, the intensity of unique flood related tweets during a flood event, peaked at 8 tweets per second during floods in early 2014. A fair amount of these tweets also contains observations of water depth and location. Our hypothesis is that based on the large numbers of tweets it is possible to generate real-time flood extent maps. In this study we use tweets from the city of Jakarta, Indonesia, to generate these flood extent maps. The data-mining procedure looks for tweets with a mention of 'banjir', the Bahasa Indonesia word for flood. It then removes modified and retweeted messages in order to keep unique tweets only. Since tweets are not always sent directly from the location of observation, the geotag in the tweets is unreliable. We therefore extract location information using mentions of names of neighborhoods and points of interest. Finally, where encountered, a mention of a length measure is extracted as water depth. These tweets containing a location reference and a water level are considered to be flood observations. The strength of this method is that it can easily be extended to other regions and languages. Based on the intensity of tweets in Jakarta during a flood event we can provide a rough estimate of the flood extent. To provide more accurate flood extend

  14. Estimation of Internal Flooding Frequency for Screening Analysis of Flooding PSA

    International Nuclear Information System (INIS)

    Choi, Sun Yeong; Yang, Jun Eon

    2005-01-01

    The purpose of this paper is to estimate the internal frequency for the quantitative screening analysis of the flooding PSA (Probabilistic Safety Assessment) with the appropriate data and estimation method. In the case of the existing flood PSA for domestic NPPs (Nuclear Power Plant), the screening analysis was performed firstly and then detailed analysis was performed for the area not screened out. For the quantitative screening analysis, the plant area based flood frequency by MLE (Maximum Likelihood Estimation) method was used, while the component based flood frequency is used for the detailed analysis. The existing quantitative screening analysis for domestic NPPs have used data from all LWRs (Light Water Reactor), namely PWR (Pressurized Water Reactor) and BWR (Boiling Water Reactor) for the internal flood frequency of the auxiliary building and turbine building. However, in the case of the primary auxiliary building, the applicability of the data from all LWRs needs to be examined carefully because of the significant difference in equipments between the PWR and BWR structure. NUREG/CR-5750 suggested the Bayesian update method with Jeffrey's noninformative prior to estimate the initiating event frequency for the flood. It, however, did not describe any procedure of the flood PSA. Recently, Fleming and Lydell suggested the internal flooding frequency in the unit of the plant operation year-pipe length (in meter) by pipe size of each specific system which is susceptible to the flooding such as the service water system and the circulating water system. They used the failure rate, the rupture conditional probability given the failure to estimate the internal flooding frequency, and the Bayesian update to reduce uncertainties. To perform the quantitative screening analysis with the method, it requires pipe length by each pipe size of the specific system per each divided area to change the concept of the component based frequency to the concept of the plant area

  15. Flood Extent Mapping for Namibia Using Change Detection and Thresholding with SAR

    Science.gov (United States)

    Long, Stephanie; Fatoyinbo, Temilola E.; Policelli, Frederick

    2014-01-01

    A new method for flood detection change detection and thresholding (CDAT) was used with synthetic aperture radar (SAR) imagery to delineate the extent of flooding for the Chobe floodplain in the Caprivi region of Namibia. This region experiences annual seasonal flooding and has seen a recent renewal of severe flooding after a long dry period in the 1990s. Flooding in this area has caused loss of life and livelihoods for the surrounding communities and has caught the attention of disaster relief agencies. There is a need for flood extent mapping techniques that can be used to process images quickly, providing near real-time flooding information to relief agencies. ENVISAT/ASAR and Radarsat-2 images were acquired for several flooding seasons from February 2008 to March 2013. The CDAT method was used to determine flooding from these images and includes the use of image subtraction, decision based classification with threshold values, and segmentation of SAR images. The total extent of flooding determined for 2009, 2011 and 2012 was about 542 km2, 720 km2, and 673 km2 respectively. Pixels determined to be flooded in vegetation were typically flooding in vegetation was much greater (almost one third of the total flooded area). The time to maximum flooding for the 2013 flood season was determined to be about 27 days. Landsat water classification was used to compare the results from the new CDAT with SAR method; the results show good spatial agreement with Landsat scenes.

  16. Estimating design flood and HEC-RAS modelling approach for flood analysis in Bojonegoro city

    Science.gov (United States)

    Prastica, R. M. S.; Maitri, C.; Hermawan, A.; Nugroho, P. C.; Sutjiningsih, D.; Anggraheni, E.

    2018-03-01

    Bojonegoro faces flood every year with less advanced prevention development. Bojonegoro city development could not peak because the flood results material losses. It affects every sectors in Bojonegoro: education, politics, economy, social, and infrastructure development. This research aims to analyse and to ensure that river capacity has high probability to be the main factor of flood in Bojonegoro. Flood discharge analysis uses Nakayasu synthetic unit hydrograph for period of 5 years, 10 years, 25 years, 50 years, and 100 years. They would be compared to the water maximum capacity that could be loaded by downstream part of Bengawan Solo River in Bojonegoro. According to analysis result, Bengawan Solo River in Bojonegoro could not able to load flood discharges. Another method used is HEC-RAS analysis. The conclusion that shown by HEC-RAS analysis has the same view. It could be observed that flood water loading is more than full bank capacity elevation in the river. To conclude, the main factor that should be noticed by government to solve flood problem is river capacity.

  17. A European Flood Database: facilitating comprehensive flood research beyond administrative boundaries

    Directory of Open Access Journals (Sweden)

    J. Hall

    2015-06-01

    Full Text Available The current work addresses one of the key building blocks towards an improved understanding of flood processes and associated changes in flood characteristics and regimes in Europe: the development of a comprehensive, extensive European flood database. The presented work results from ongoing cross-border research collaborations initiated with data collection and joint interpretation in mind. A detailed account of the current state, characteristics and spatial and temporal coverage of the European Flood Database, is presented. At this stage, the hydrological data collection is still growing and consists at this time of annual maximum and daily mean discharge series, from over 7000 hydrometric stations of various data series lengths. Moreover, the database currently comprises data from over 50 different data sources. The time series have been obtained from different national and regional data sources in a collaborative effort of a joint European flood research agreement based on the exchange of data, models and expertise, and from existing international data collections and open source websites. These ongoing efforts are contributing to advancing the understanding of regional flood processes beyond individual country boundaries and to a more coherent flood research in Europe.

  18. Maximum likely scale estimation

    DEFF Research Database (Denmark)

    Loog, Marco; Pedersen, Kim Steenstrup; Markussen, Bo

    2005-01-01

    A maximum likelihood local scale estimation principle is presented. An actual implementation of the estimation principle uses second order moments of multiple measurements at a fixed location in the image. These measurements consist of Gaussian derivatives possibly taken at several scales and/or ...

  19. Robust Maximum Association Estimators

    NARCIS (Netherlands)

    A. Alfons (Andreas); C. Croux (Christophe); P. Filzmoser (Peter)

    2017-01-01

    textabstractThe maximum association between two multivariate variables X and Y is defined as the maximal value that a bivariate association measure between one-dimensional projections αX and αY can attain. Taking the Pearson correlation as projection index results in the first canonical correlation

  20. Evaluation of design flood estimates with respect to sample size

    Science.gov (United States)

    Kobierska, Florian; Engeland, Kolbjorn

    2016-04-01

    Estimation of design floods forms the basis for hazard management related to flood risk and is a legal obligation when building infrastructure such as dams, bridges and roads close to water bodies. Flood inundation maps used for land use planning are also produced based on design flood estimates. In Norway, the current guidelines for design flood estimates give recommendations on which data, probability distribution, and method to use dependent on length of the local record. If less than 30 years of local data is available, an index flood approach is recommended where the local observations are used for estimating the index flood and regional data are used for estimating the growth curve. For 30-50 years of data, a 2 parameter distribution is recommended, and for more than 50 years of data, a 3 parameter distribution should be used. Many countries have national guidelines for flood frequency estimation, and recommended distributions include the log Pearson II, generalized logistic and generalized extreme value distributions. For estimating distribution parameters, ordinary and linear moments, maximum likelihood and Bayesian methods are used. The aim of this study is to r-evaluate the guidelines for local flood frequency estimation. In particular, we wanted to answer the following questions: (i) Which distribution gives the best fit to the data? (ii) Which estimation method provides the best fit to the data? (iii) Does the answer to (i) and (ii) depend on local data availability? To answer these questions we set up a test bench for local flood frequency analysis using data based cross-validation methods. The criteria were based on indices describing stability and reliability of design flood estimates. Stability is used as a criterion since design flood estimates should not excessively depend on the data sample. The reliability indices describe to which degree design flood predictions can be trusted.

  1. Development of Positive Matrix Factorization Model (PMF) to Annual Study of the PM2.5 Organic Composition in ChapinerIa; Desarrollo del Modelo de Factorizacion de la Matriz Positiva (PMF) al Estudio Anual de la Composicion Organica del PM2.5 en Chapineria

    Energy Technology Data Exchange (ETDEWEB)

    Pindado, O.; Perez, R. M.; Garcia, S.

    2013-05-01

    The Positive Matrix Factorization (PMF) application to a set of PM2.5 data collected in a rural area of Madrid for a period of 1 year has been developed. Results has let describing the particulate faction of atmospheric aerosol collected in Chapineria according to 7 factor, among them fossil fuel combustion by traffic, wax plants, primary emissions of organic carbon, crustal material, and secondary organic aerosol. Five of these factors are related to primary particles; meanwhile only one factor has been associated to secondary particles. Finally, a factor has not been associated to any known source of particulate matter. (Author)

  2. Maximum power point tracking

    International Nuclear Information System (INIS)

    Enslin, J.H.R.

    1990-01-01

    A well engineered renewable remote energy system, utilizing the principal of Maximum Power Point Tracking can be m ore cost effective, has a higher reliability and can improve the quality of life in remote areas. This paper reports that a high-efficient power electronic converter, for converting the output voltage of a solar panel, or wind generator, to the required DC battery bus voltage has been realized. The converter is controlled to track the maximum power point of the input source under varying input and output parameters. Maximum power point tracking for relative small systems is achieved by maximization of the output current in a battery charging regulator, using an optimized hill-climbing, inexpensive microprocessor based algorithm. Through practical field measurements it is shown that a minimum input source saving of 15% on 3-5 kWh/day systems can easily be achieved. A total cost saving of at least 10-15% on the capital cost of these systems are achievable for relative small rating Remote Area Power Supply systems. The advantages at larger temperature variations and larger power rated systems are much higher. Other advantages include optimal sizing and system monitor and control

  3. Discover Floods Educators Guide

    Science.gov (United States)

    Project WET Foundation, 2009

    2009-01-01

    Now available as a Download! This valuable resource helps educators teach students about both the risks and benefits of flooding through a series of engaging, hands-on activities. Acknowledging the different roles that floods play in both natural and urban communities, the book helps young people gain a global understanding of this common--and…

  4. Flood action plans

    International Nuclear Information System (INIS)

    Slopek, R.J.

    1995-01-01

    Safe operating procedures developed by TransAlta Utilities for dealing with flooding, resulting from upstream dam failures or extreme rainfalls, were presented. Several operating curves developed by Monenco AGRA were described, among them the No Overtopping Curve (NOC), the Safe Filling Curve (SFC), the No Spill Curve (NSC) and the Guaranteed Fill Curve (GFC). The concept of an operational comfort zone was developed and defined. A flood action plan for all operating staff was created as a guide in case of a flooding incident. Staging of a flood action plan workshop was described. Dam break scenarios pertinent to the Bow River were developed for subsequent incorporation into a Flood Action Plan Manual. Evaluation of the technical presentations made during workshops were found them to have been effective in providing operating staff with a better understanding of the procedures that they would perform in an emergency. 8 figs

  5. Maximum entropy methods

    International Nuclear Information System (INIS)

    Ponman, T.J.

    1984-01-01

    For some years now two different expressions have been in use for maximum entropy image restoration and there has been some controversy over which one is appropriate for a given problem. Here two further entropies are presented and it is argued that there is no single correct algorithm. The properties of the four different methods are compared using simple 1D simulations with a view to showing how they can be used together to gain as much information as possible about the original object. (orig.)

  6. Distillation Column Flooding Predictor

    Energy Technology Data Exchange (ETDEWEB)

    George E. Dzyacky

    2010-11-23

    The Flooding Predictor™ is a patented advanced control technology proven in research at the Separations Research Program, University of Texas at Austin, to increase distillation column throughput by over 6%, while also increasing energy efficiency by 10%. The research was conducted under a U. S. Department of Energy Cooperative Agreement awarded to George Dzyacky of 2ndpoint, LLC. The Flooding Predictor™ works by detecting the incipient flood point and controlling the column closer to its actual hydraulic limit than historical practices have allowed. Further, the technology uses existing column instrumentation, meaning no additional refining infrastructure is required. Refiners often push distillation columns to maximize throughput, improve separation, or simply to achieve day-to-day optimization. Attempting to achieve such operating objectives is a tricky undertaking that can result in flooding. Operators and advanced control strategies alike rely on the conventional use of delta-pressure instrumentation to approximate the column’s approach to flood. But column delta-pressure is more an inference of the column’s approach to flood than it is an actual measurement of it. As a consequence, delta pressure limits are established conservatively in order to operate in a regime where the column is never expected to flood. As a result, there is much “left on the table” when operating in such a regime, i.e. the capacity difference between controlling the column to an upper delta-pressure limit and controlling it to the actual hydraulic limit. The Flooding Predictor™, an innovative pattern recognition technology, controls columns at their actual hydraulic limit, which research shows leads to a throughput increase of over 6%. Controlling closer to the hydraulic limit also permits operation in a sweet spot of increased energy-efficiency. In this region of increased column loading, the Flooding Predictor is able to exploit the benefits of higher liquid

  7. Iowa Flood Information System

    Science.gov (United States)

    Demir, I.; Krajewski, W. F.; Goska, R.; Mantilla, R.; Weber, L. J.; Young, N.

    2011-12-01

    The Iowa Flood Information System (IFIS) is a web-based platform developed by the Iowa Flood Center (IFC) to provide access to flood inundation maps, real-time flood conditions, flood forecasts both short-term and seasonal, flood-related data, information and interactive visualizations for communities in Iowa. The key element of the system's architecture is the notion of community. Locations of the communities, those near streams and rivers, define basin boundaries. The IFIS provides community-centric watershed and river characteristics, weather (rainfall) conditions, and streamflow data and visualization tools. Interactive interfaces allow access to inundation maps for different stage and return period values, and flooding scenarios with contributions from multiple rivers. Real-time and historical data of water levels, gauge heights, and rainfall conditions are available in the IFIS by streaming data from automated IFC bridge sensors, USGS stream gauges, NEXRAD radars, and NWS forecasts. Simple 2D and 3D interactive visualizations in the IFIS make the data more understandable to general public. Users are able to filter data sources for their communities and selected rivers. The data and information on IFIS is also accessible through web services and mobile applications. The IFIS is optimized for various browsers and screen sizes to provide access through multiple platforms including tablets and mobile devices. The IFIS includes a rainfall-runoff forecast model to provide a five-day flood risk estimate for around 500 communities in Iowa. Multiple view modes in the IFIS accommodate different user types from general public to researchers and decision makers by providing different level of tools and details. River view mode allows users to visualize data from multiple IFC bridge sensors and USGS stream gauges to follow flooding condition along a river. The IFIS will help communities make better-informed decisions on the occurrence of floods, and will alert communities

  8. The last glacial maximum

    Science.gov (United States)

    Clark, P.U.; Dyke, A.S.; Shakun, J.D.; Carlson, A.E.; Clark, J.; Wohlfarth, B.; Mitrovica, J.X.; Hostetler, S.W.; McCabe, A.M.

    2009-01-01

    We used 5704 14C, 10Be, and 3He ages that span the interval from 10,000 to 50,000 years ago (10 to 50 ka) to constrain the timing of the Last Glacial Maximum (LGM) in terms of global ice-sheet and mountain-glacier extent. Growth of the ice sheets to their maximum positions occurred between 33.0 and 26.5 ka in response to climate forcing from decreases in northern summer insolation, tropical Pacific sea surface temperatures, and atmospheric CO2. Nearly all ice sheets were at their LGM positions from 26.5 ka to 19 to 20 ka, corresponding to minima in these forcings. The onset of Northern Hemisphere deglaciation 19 to 20 ka was induced by an increase in northern summer insolation, providing the source for an abrupt rise in sea level. The onset of deglaciation of the West Antarctic Ice Sheet occurred between 14 and 15 ka, consistent with evidence that this was the primary source for an abrupt rise in sea level ???14.5 ka.

  9. An integrated analysis of the March 2015 Atacama floods

    Science.gov (United States)

    Wilcox, Andrew C.; Escauriaza, Cristian; Agredano, Roberto; Mignot, Emmanuel; Zuazo, Vicente; Otárola, Sebastián.; Castro, Lina; Gironás, Jorge; Cienfuegos, Rodrigo; Mao, Luca

    2016-08-01

    In March 2015 unusual ocean and atmospheric conditions produced many years' worth of rainfall in a 48 h period over northern Chile's Atacama Desert, one of Earth's driest regions, resulting in catastrophic flooding. Here we describe the hydrologic and geomorphic drivers of and responses to the 2015 Atacama floods. In the Salado River, we estimated a flood peak discharge of approximately 1000 m3/s, which caused widespread damage and high sediment loads that were primarily derived from valley-fill erosion; hillslopes remained surprisingly intact despite their lack of vegetation. In the coastal city of Chañaral, flooding of the Salado River produced maximum water depths over 4.5 m, meters thick mud deposition in buildings and along city streets, and coastal erosion. The Atacama flooding has broad implications in the context of hazard reduction, erosion of contaminated legacy mine tailings, and the Atacama's status as a terrestrial analog for Mars.

  10. Maximum Entropy Fundamentals

    Directory of Open Access Journals (Sweden)

    F. Topsøe

    2001-09-01

    Full Text Available Abstract: In its modern formulation, the Maximum Entropy Principle was promoted by E.T. Jaynes, starting in the mid-fifties. The principle dictates that one should look for a distribution, consistent with available information, which maximizes the entropy. However, this principle focuses only on distributions and it appears advantageous to bring information theoretical thinking more prominently into play by also focusing on the "observer" and on coding. This view was brought forward by the second named author in the late seventies and is the view we will follow-up on here. It leads to the consideration of a certain game, the Code Length Game and, via standard game theoretical thinking, to a principle of Game Theoretical Equilibrium. This principle is more basic than the Maximum Entropy Principle in the sense that the search for one type of optimal strategies in the Code Length Game translates directly into the search for distributions with maximum entropy. In the present paper we offer a self-contained and comprehensive treatment of fundamentals of both principles mentioned, based on a study of the Code Length Game. Though new concepts and results are presented, the reading should be instructional and accessible to a rather wide audience, at least if certain mathematical details are left aside at a rst reading. The most frequently studied instance of entropy maximization pertains to the Mean Energy Model which involves a moment constraint related to a given function, here taken to represent "energy". This type of application is very well known from the literature with hundreds of applications pertaining to several different elds and will also here serve as important illustration of the theory. But our approach reaches further, especially regarding the study of continuity properties of the entropy function, and this leads to new results which allow a discussion of models with so-called entropy loss. These results have tempted us to speculate over

  11. Health impacts of floods.

    Science.gov (United States)

    Du, Weiwei; FitzGerald, Gerard Joseph; Clark, Michele; Hou, Xiang-Yu

    2010-01-01

    Floods are the most common hazard to cause disasters and have led to extensive morbidity and mortality throughout the world. The impact of floods on the human community is related directly to the location and topography of the area, as well as human demographics and characteristics of the built environment. The aim of this study is to identify the health impacts of disasters and the underlying causes of health impacts associated with floods. A conceptual framework is developed that may assist with the development of a rational and comprehensive approach to prevention, mitigation, and management. This study involved an extensive literature review that located >500 references, which were analyzed to identify common themes, findings, and expert views. The findings then were distilled into common themes. The health impacts of floods are wide ranging, and depend on a number of factors. However, the health impacts of a particular flood are specific to the particular context. The immediate health impacts of floods include drowning, injuries, hypothermia, and animal bites. Health risks also are associated with the evacuation of patients, loss of health workers, and loss of health infrastructure including essential drugs and supplies. In the medium-term, infected wounds, complications of injury, poisoning, poor mental health, communicable diseases, and starvation are indirect effects of flooding. In the long-term, chronic disease, disability, poor mental health, and poverty-related diseases including malnutrition are the potential legacy. This article proposes a structured approach to the classification of the health impacts of floods and a conceptual framework that demonstrates the relationships between floods and the direct and indirect health consequences.

  12. Introduction to maximum entropy

    International Nuclear Information System (INIS)

    Sivia, D.S.

    1988-01-01

    The maximum entropy (MaxEnt) principle has been successfully used in image reconstruction in a wide variety of fields. We review the need for such methods in data analysis and show, by use of a very simple example, why MaxEnt is to be preferred over other regularizing functions. This leads to a more general interpretation of the MaxEnt method, and its use is illustrated with several different examples. Practical difficulties with non-linear problems still remain, this being highlighted by the notorious phase problem in crystallography. We conclude with an example from neutron scattering, using data from a filter difference spectrometer to contrast MaxEnt with a conventional deconvolution. 12 refs., 8 figs., 1 tab

  13. Solar maximum observatory

    International Nuclear Information System (INIS)

    Rust, D.M.

    1984-01-01

    The successful retrieval and repair of the Solar Maximum Mission (SMM) satellite by Shuttle astronauts in April 1984 permitted continuance of solar flare observations that began in 1980. The SMM carries a soft X ray polychromator, gamma ray, UV and hard X ray imaging spectrometers, a coronagraph/polarimeter and particle counters. The data gathered thus far indicated that electrical potentials of 25 MeV develop in flares within 2 sec of onset. X ray data show that flares are composed of compressed magnetic loops that have come too close together. Other data have been taken on mass ejection, impacts of electron beams and conduction fronts with the chromosphere and changes in the solar radiant flux due to sunspots. 13 references

  14. Introduction to maximum entropy

    International Nuclear Information System (INIS)

    Sivia, D.S.

    1989-01-01

    The maximum entropy (MaxEnt) principle has been successfully used in image reconstruction in a wide variety of fields. The author reviews the need for such methods in data analysis and shows, by use of a very simple example, why MaxEnt is to be preferred over other regularizing functions. This leads to a more general interpretation of the MaxEnt method, and its use is illustrated with several different examples. Practical difficulties with non-linear problems still remain, this being highlighted by the notorious phase problem in crystallography. He concludes with an example from neutron scattering, using data from a filter difference spectrometer to contrast MaxEnt with a conventional deconvolution. 12 refs., 8 figs., 1 tab

  15. Functional Maximum Autocorrelation Factors

    DEFF Research Database (Denmark)

    Larsen, Rasmus; Nielsen, Allan Aasbjerg

    2005-01-01

    MAF outperforms the functional PCA in concentrating the interesting' spectra/shape variation in one end of the eigenvalue spectrum and allows for easier interpretation of effects. Conclusions. Functional MAF analysis is a useful methods for extracting low dimensional models of temporally or spatially......Purpose. We aim at data where samples of an underlying function are observed in a spatial or temporal layout. Examples of underlying functions are reflectance spectra and biological shapes. We apply functional models based on smoothing splines and generalize the functional PCA in......\\verb+~+\\$\\backslash\\$cite{ramsay97} to functional maximum autocorrelation factors (MAF)\\verb+~+\\$\\backslash\\$cite{switzer85,larsen2001d}. We apply the method to biological shapes as well as reflectance spectra. {\\$\\backslash\\$bf Methods}. MAF seeks linear combination of the original variables that maximize autocorrelation between...

  16. Regularized maximum correntropy machine

    KAUST Repository

    Wang, Jim Jing-Yan; Wang, Yunji; Jing, Bing-Yi; Gao, Xin

    2015-01-01

    In this paper we investigate the usage of regularized correntropy framework for learning of classifiers from noisy labels. The class label predictors learned by minimizing transitional loss functions are sensitive to the noisy and outlying labels of training samples, because the transitional loss functions are equally applied to all the samples. To solve this problem, we propose to learn the class label predictors by maximizing the correntropy between the predicted labels and the true labels of the training samples, under the regularized Maximum Correntropy Criteria (MCC) framework. Moreover, we regularize the predictor parameter to control the complexity of the predictor. The learning problem is formulated by an objective function considering the parameter regularization and MCC simultaneously. By optimizing the objective function alternately, we develop a novel predictor learning algorithm. The experiments on two challenging pattern classification tasks show that it significantly outperforms the machines with transitional loss functions.

  17. Regularized maximum correntropy machine

    KAUST Repository

    Wang, Jim Jing-Yan

    2015-02-12

    In this paper we investigate the usage of regularized correntropy framework for learning of classifiers from noisy labels. The class label predictors learned by minimizing transitional loss functions are sensitive to the noisy and outlying labels of training samples, because the transitional loss functions are equally applied to all the samples. To solve this problem, we propose to learn the class label predictors by maximizing the correntropy between the predicted labels and the true labels of the training samples, under the regularized Maximum Correntropy Criteria (MCC) framework. Moreover, we regularize the predictor parameter to control the complexity of the predictor. The learning problem is formulated by an objective function considering the parameter regularization and MCC simultaneously. By optimizing the objective function alternately, we develop a novel predictor learning algorithm. The experiments on two challenging pattern classification tasks show that it significantly outperforms the machines with transitional loss functions.

  18. 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.

  19. Nogales flood detention study

    Science.gov (United States)

    Norman, Laura M.; Levick, Lainie; Guertin, D. Phillip; Callegary, James; Guadarrama, Jesus Quintanar; Anaya, Claudia Zulema Gil; Prichard, Andrea; Gray, Floyd; Castellanos, Edgar; Tepezano, Edgar; Huth, Hans; Vandervoet, Prescott; Rodriguez, Saul; Nunez, Jose; Atwood, Donald; Granillo, Gilberto Patricio Olivero; Ceballos, Francisco Octavio Gastellum

    2010-01-01

    Flooding in Ambos Nogales often exceeds the capacity of the channel and adjacent land areas, endangering many people. The Nogales Wash is being studied to prevent future flood disasters and detention features are being installed in tributaries of the wash. This paper describes the application of the KINEROS2 model and efforts to understand the capacity of these detention features under various flood and urbanization scenarios. Results depict a reduction in peak flow for the 10-year, 1-hour event based on current land use in tributaries with detention features. However, model results also demonstrate that larger storm events and increasing urbanization will put a strain on the features and limit their effectiveness.

  20. Development of flood index by characterisation of flood hydrographs

    Science.gov (United States)

    Bhattacharya, Biswa; Suman, Asadusjjaman

    2015-04-01

    In recent years the world has experienced deaths, large-scale displacement of people, billions of Euros of economic damage, mental stress and ecosystem impacts due to flooding. Global changes (climate change, population and economic growth, and urbanisation) are exacerbating the severity of flooding. The 2010 floods in Pakistan and the 2011 floods in Australia and Thailand demonstrate the need for concerted action in the face of global societal and environmental changes to strengthen resilience against flooding. Due to climatological characteristics there are catchments where flood forecasting may have a relatively limited role and flood event management may have to be trusted upon. For example, in flash flood catchments, which often may be tiny and un-gauged, flood event management often depends on approximate prediction tools such as flash flood guidance (FFG). There are catchments fed largely by flood waters coming from upstream catchments, which are un-gauged or due to data sharing issues in transboundary catchments the flow of information from upstream catchment is limited. Hydrological and hydraulic modelling of these downstream catchments will never be sufficient to provide any required forecasting lead time and alternative tools to support flood event management will be required. In FFG, or similar approaches, the primary motif is to provide guidance by synthesising the historical data. We follow a similar approach to characterise past flood hydrographs to determine a flood index (FI), which varies in space and time with flood magnitude and its propagation. By studying the variation of the index the pockets of high flood risk, requiring attention, can be earmarked beforehand. This approach can be very useful in flood risk management of catchments where information about hydro-meteorological variables is inadequate for any forecasting system. This paper presents the development of FI and its application to several catchments including in Kentucky in the USA

  1. Legitimizing differentiated flood protection levels

    NARCIS (Netherlands)

    Thomas, Hartmann; Spit, Tejo

    2016-01-01

    The European flood risk management plan is a new instrument introduced by the Floods Directive. It introduces a spatial turn and a scenario approach in flood risk management, ultimately leading to differentiated flood protection levels on a catchment basis. This challenges the traditional sources of

  2. Spatial coherence of flood-rich and flood-poor periods across Germany

    Science.gov (United States)

    Merz, Bruno; Dung, Nguyen Viet; Apel, Heiko; Gerlitz, Lars; Schröter, Kai; Steirou, Eva; Vorogushyn, Sergiy

    2018-04-01

    Despite its societal relevance, the question whether fluctuations in flood occurrence or magnitude are coherent in space has hardly been addressed in quantitative terms. We investigate this question for Germany by analysing fluctuations in annual maximum series (AMS) values at 68 discharge gauges for the common time period 1932-2005. We find remarkable spatial coherence across Germany given its different flood regimes. For example, there is a tendency that flood-rich/-poor years in sub-catchments of the Rhine basin, which are dominated by winter floods, coincide with flood-rich/-poor years in the southern sub-catchments of the Danube basin, which have their dominant flood season in summer. Our findings indicate that coherence is caused rather by persistence in catchment wetness than by persistent periods of higher/lower event precipitation. Further, we propose to differentiate between event-type and non-event-type coherence. There are quite a number of hydrological years with considerable non-event-type coherence, i.e. AMS values of the 68 gauges are spread out through the year but in the same magnitude range. Years with extreme flooding tend to be of event-type and non-coherent, i.e. there is at least one precipitation event that affects many catchments to various degree. Although spatial coherence is a remarkable phenomenon, and large-scale flooding across Germany can lead to severe situations, extreme magnitudes across the whole country within one event or within one year were not observed in the investigated period.

  3. Summary of floods in the United States during 1958

    Science.gov (United States)

    Hendricks, E.L.

    1964-01-01

    This report describes the most outstanding floods that occurred in the United States during 1958.A series of storms from January 23 to February 16 brought large amounts of precipitation to northern California and produced damaging floods, particularly in the Lower Sacramento Valley where losses totaled about \\$12 million.Major floods, notable because of the large area affected, occurred on many small streams in central and south Texas, following heavy general rains in late February. Extensive flooding occurred along the Gulf Coastal plain on the lower reaches of the major streams from the Brazos River to the Nueces River. Two lives were lost, and property damage exceeded \\$1 million.Damaging floods of April 1-7 followed one of the wettest winters in California history. Swollen streams overflowed their banks throughout the central part of the State, and discharge peaks on many streams exceeded those .of the floods of December 1955. Most severely flooded was the San Francisco Bay area. Total flood damage was estimated at \\$23 million.The storms and floods of April-May in Louisiana and adjacent States outranked all other floods in the United States during 1958 with respect to intensity of rain over a large area, number of streams having maximum discharge of record, rare occurrence of peaks, and great amount (\\$21 million) of resultant damage.Heavy rains on June 8-15 caused one of the greatest summer floods of record in central Indiana. Peak discharges were high and of rare occurrences. Failure of numerous levees along the Wabash River caused great damage. Crop damage alone was estimated at \\$48 million.Intense rains of July 1-2 caused record-breaking floods in southwestern Iowa. Rapid rises and the great magnitude of the floods on small streams resulted in 18 deaths and many injuries. Six towns and cities along the East Nishnabotna River and its tributaries were particularly hard hit; rural damage was also high. Total damage was estimated at \\$15 million

  4. Hourly elemental concentrations in PM2.5 aerosols sampled simultaneously at urban background and road site during SAPUSS - diurnal variations and PMF receptor modelling

    Science.gov (United States)

    Dall'Osto, M.; Querol, X.; Amato, F.; Karanasiou, A.; Lucarelli, F.; Nava, S.; Calzolai, G.; Chiari, M.

    2013-04-01

    Hourly-resolved aerosol chemical speciation data can be a highly powerful tool to determine the source origin of atmospheric pollutants in urban environments. Aerosol mass concentrations of seventeen elements (Na, Mg, Al, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Sr and Pb) were obtained by time (1 h) and size (PM2.5 particulate matter Spain) during September-October 2010: an urban background site (UB) and a street canyon traffic road site (RS). Elements related to primary non-exhaust traffic emission (Fe, Cu), dust resuspension (Ca) and anthropogenic Cl were found enhanced at the RS, whereas industrial related trace metals (Zn, Pb, Mn) were found at higher concentrations at the more ventilated UB site. When receptor modelling was performed with positive matrix factorization (PMF), nine different aerosol sources were identified at both sites: three types of regional aerosols (regional sulphate (S) - 27%, biomass burning (K) - 5%, sea salt (Na-Mg) - 17%), three types of dust aerosols (soil dust (Al-Ti) - 17%, urban crustal dust (Ca) - 6%, and primary traffic non-exhaust brake dust (Fe-Cu) - 7%), and three types of industrial aerosol plumes-like events (shipping oil combustion (V-Ni) - 17%, industrial smelters (Zn-Mn) - 3%, and industrial combustion (Pb-Cl) - 5%, percentages presented are average source contributions to the total elemental mass measured). The validity of the PMF solution of the PIXE data is supported by very good correlations with external single particle mass spectrometry measurements. Some important conclusions can be drawn about the PM2.5 mass fraction simultaneously measured at the UB and RS sites: (1) the regional aerosol sources impact both monitoring sites at similar concentrations regardless their different ventilation conditions; (2) by contrast, local industrial aerosol plumes associated with shipping oil combustion and smelters activities have a higher impact on the more ventilated UB site; (3) a unique source of Pb-Cl (associated with

  5. Flood-proof motors

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, Marcus [AREVA NP GmbH, Erlangen (Germany)

    2013-07-01

    Even before the Fukushima event occurred some German nuclear power plants (NPP) have considered flooding scenarios. As a result of one of these studies, AREVA performed an upgrade project in NPP Isar 1 with flood-proof motors as a replacement of existing air-cooled low-voltage and high-voltage motors of the emergency cooling chain. After the Fukushima event, in which the cooling chains failed, the topic flood-proof equipment gets more and more into focus. This compact will introduce different kinds of flood-proof electrical motors which are currently installed or planned for installation into NPPs over the world. Moreover the process of qualification, as it was performed during the project in NPP Isar 1, will be shown. (orig.)

  6. Floods and Mold Growth

    Science.gov (United States)

    Mold growth may be a problem after flooding. Excess moisture in the home is cause for concern about indoor air quality primarily because it provides breeding conditions for pests, molds and other microorganisms.

  7. FLOODPLAIN, FLOOD COUNTY, USA

    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...

  8. Flood-proof motors

    International Nuclear Information System (INIS)

    Schmitt, Marcus

    2013-01-01

    Even before the Fukushima event occurred some German nuclear power plants (NPP) have considered flooding scenarios. As a result of one of these studies, AREVA performed an upgrade project in NPP Isar 1 with flood-proof motors as a replacement of existing air-cooled low-voltage and high-voltage motors of the emergency cooling chain. After the Fukushima event, in which the cooling chains failed, the topic flood-proof equipment gets more and more into focus. This compact will introduce different kinds of flood-proof electrical motors which are currently installed or planned for installation into NPPs over the world. Moreover the process of qualification, as it was performed during the project in NPP Isar 1, will be shown. (orig.)

  9. 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.

  10. Understanding Flood Seasonality and Its Temporal Shifts within the Contiguous United States

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Sheng [Institute of Hydrology and Water Resources, School of Civil Engineering, Zhejiang University, Hangzhou, China; Li, Hong-Yi [Pacific Northwest National Laboratory, Richland, Washington; Leung, L. Ruby [Pacific Northwest National Laboratory, Richland, Washington; Guo, Jiali [College of Civil and Hydropower Engineering, China Three Gorges University, Yichang, China; State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, China; Ran, Qihua [Institute of Hydrology and Water Resources, School of Civil Engineering, Zhejiang University, Hangzhou, China; Demissie, Yonas [Department of Civil and Environmental Engineering, Washington State University Tri-Cities, Richland, Washington; Sivapalan, Murugesu [Department of Geography and Geographic Information Science, University of Illinois at Urbana–Champaign, Champaign, Illinois; Department of Civil and Environmental Engineering, University of Illinois at Urbana–Champaign, Urbana, Illinois

    2017-07-01

    Understanding the causes of flood seasonality is critical for better flood management. This study examines the seasonality of annual maximum floods (AMF) and its changes before and after 1980 at over 250 natural catchments across the contiguous United States. Using circular statistics to define a seasonality index, our analysis focuses on the variability of the flood occurrence date. Generally, catchments with more synchronized seasonal water and energy cycles largely inherit their seasonality of AMF from that of annual maximum rainfall (AMR). In contrast, the seasonality of AMF in catchments with loosely synchronized water and energy cycles are more influenced by high antecedent storage, which is responsible for the amplification of the seasonality of AMF over that of AMR. This understanding then effectively explains a statistically significant shift of flood seasonality detected in some catchments in the recent decades. Catchments where the antecedent soil water storage has increased since 1980 exhibit increasing flood seasonality while catchments that have experienced increases in storm rainfall before the floods have shifted towards floods occurring more variably across the seasons. In the eastern catchments, a concurrent widespread increase in event rainfall magnitude and reduced soil water storage have led to a more variable timing of floods. Our findings of the role of antecedent storage and event rainfall on the flood seasonality provide useful insights for understanding future changes in flood seasonality as climate models projected changes in extreme precipitation and aridity over land.

  11. Geographical information system (GIS) application for flood prediction at Sungai Sembrong

    Science.gov (United States)

    Kamin, Masiri; Ahmad, Nor Farah Atiqah; Razali, Siti Nooraiin Mohd; Hilaham, Mashuda Mohamad; Rahman, Mohamad Abdul; Ngadiman, Norhayati; Sahat, Suhaila

    2017-10-01

    The occurrence of flood is one of natural disaster that often beset Malaysia. The latest incident that happened in 2007 was the worst occurrence of floods ever be set in Johor. Reporting floods mainly focused on rising water rising levels, so about once a focus on the area of flood delineation. A study focused on the effectiveness of using Geographic Information System (GIS) to predict the flood by taking Sg. Sembrong, Batu Pahat, Johor as study area. This study combined hydrological model and water balance model in the display to show the expected flood area for future reference. The minimum, maximum and average rainfall data for January 2007 at Sg Sembrong were used in this study. The data shows that flood does not occurs at the minimum and average rainfall of 17.2mm and 2mm respectively. At maximum rainfall, 203mm, shows the flood area was 9983 hectares with the highest level of the water depth was 2m. The result showed that the combination of hydrological models and water balance model in GIS is very suitable to be used as a tool to obtain preliminary information on flood immediately. Besides that, GIS system is a very powerful tool used in hydrology engineering to help the engineer and planner to imagine the real situation of flood events, doing flood analysis, problem solving and provide a rational, accurate and efficient decision making.

  12. Solar maximum mission

    International Nuclear Information System (INIS)

    Ryan, J.

    1981-01-01

    By understanding the sun, astrophysicists hope to expand this knowledge to understanding other stars. To study the sun, NASA launched a satellite on February 14, 1980. The project is named the Solar Maximum Mission (SMM). The satellite conducted detailed observations of the sun in collaboration with other satellites and ground-based optical and radio observations until its failure 10 months into the mission. The main objective of the SMM was to investigate one aspect of solar activity: solar flares. A brief description of the flare mechanism is given. The SMM satellite was valuable in providing information on where and how a solar flare occurs. A sequence of photographs of a solar flare taken from SMM satellite shows how a solar flare develops in a particular layer of the solar atmosphere. Two flares especially suitable for detailed observations by a joint effort occurred on April 30 and May 21 of 1980. These flares and observations of the flares are discussed. Also discussed are significant discoveries made by individual experiments

  13. Backwater Flooding in San Marcos, TX from the Blanco River

    Science.gov (United States)

    Earl, Richard; Gaenzle, Kyle G.; Hollier, Andi B.

    2016-01-01

    Large sections of San Marcos, TX were flooded in Oct. 1998, May 2015, and Oct. 2015. Much of the flooding in Oct. 1998 and Oct. 2015 was produced by overbank flooding of San Marcos River and its tributaries by spills from upstream dams. The May 2015 flooding was almost entirely produced by backwater flooding from the Blanco River whose confluence is approximately 2.2 miles southeast of downtown. We use the stage height of the Blanco River to generate maps of the areas of San Marcos that are lower than the flood peaks and compare those results with data for the observed extent of flooding in San Marcos. Our preliminary results suggest that the flooding occurred at locations more than 20 feet lower than the maximum stage height of the Blanco River at San Marcos gage (08171350). This suggest that the datum for either gage 08171350 or 08170500 (San Marcos River at San Marcos) or both are incorrect. There are plans for the U.S. Army Corps of Engineers to construct a Blanco River bypass that will divert Blanco River floodwaters approximately 2 miles farther downstream, but the $60 million price makes its implementation problematic.

  14. 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

  15. Commonalities and Differences in Flood-Generating Processes across the US

    Science.gov (United States)

    Li, X.; Troy, T. J.

    2017-12-01

    There is significant damage caused by flood, and the flood risk is increasing in the future, but there is large uncertainty in future decadal projections of flooding. In order to improve these projections, we must first turn to the past to understand the physical mechanisms that lead to flooding in basins across spatial scales and elevation ranges. To do this, we calculated the seasonality of annual maximum flows and other climatic factors to identify the flood-generating process in 2566 basins across the continental US. For most regions, the seasonality of heavy precipitation is not in phase with the seasonality of flooding, pointing to the importance of antecedent soil moisture and snow in determining flooding over much of the US. To determine the characteristic conditions leading to a flood, we classified all floods into those with different rainfall durations and with/without snow presence. Analyzing the influence of elevation, slope and drainage area, we identified patterns: the probability of flooding due to long duration precipitation increases as drainage area increases and snow present during a flood becomes increasingly likely as average basin elevation increases. To better understand the relationship between heavy rainfall and high streamflow, we calculated conditioned probability of occurrence. The southeastern US has a higher probability of occurrence for extreme Q with the same level of extreme precipitation in winter and spring than the northern US. This work is the first to look at how flood mechanisms vary across the continental US with drainage area, climate, and elevation.

  16. Mitigating flood exposure

    Science.gov (United States)

    Shultz, James M; McLean, Andrew; Herberman Mash, Holly B; Rosen, Alexa; Kelly, Fiona; Solo-Gabriele, Helena M; Youngs Jr, Georgia A; Jensen, Jessica; Bernal, Oscar; Neria, Yuval

    2013-01-01

    Introduction. In 2011, following heavy winter snowfall, two cities bordering two rivers in North Dakota, USA faced major flood threats. Flooding was foreseeable and predictable although the extent of risk was uncertain. One community, Fargo, situated in a shallow river basin, successfully mitigated and prevented flooding. For the other community, Minot, located in a deep river valley, prevention was not possible and downtown businesses and one-quarter of the homes were inundated, in the city’s worst flood on record. We aimed at contrasting the respective hazards, vulnerabilities, stressors, psychological risk factors, psychosocial consequences, and disaster risk reduction strategies under conditions where flood prevention was, and was not, possible. Methods. We applied the “trauma signature analysis” (TSIG) approach to compare the hazard profiles, identify salient disaster stressors, document the key components of disaster risk reduction response, and examine indicators of community resilience. Results. Two demographically-comparable communities, Fargo and Minot, faced challenging river flood threats and exhibited effective coordination across community sectors. We examined the implementation of disaster risk reduction strategies in situations where coordinated citizen action was able to prevent disaster impact (hazard avoidance) compared to the more common scenario when unpreventable disaster strikes, causing destruction, harm, and distress. Across a range of indicators, it is clear that successful mitigation diminishes both physical and psychological impact, thereby reducing the trauma signature of the event. Conclusion. In contrast to experience of historic flooding in Minot, the city of Fargo succeeded in reducing the trauma signature by way of reducing risk through mitigation. PMID:28228985

  17. 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.

  18. 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

  19. Crowdsourcing detailed flood data

    Science.gov (United States)

    Walliman, Nicholas; Ogden, Ray; Amouzad*, Shahrzhad

    2015-04-01

    Over the last decade the average annual loss across the European Union due to flooding has been 4.5bn Euros, but increasingly intense rainfall, as well as population growth, urbanisation and the rising costs of asset replacements, may see this rise to 23bn Euros a year by 2050. Equally disturbing are the profound social costs to individuals, families and communities which in addition to loss of lives include: loss of livelihoods, decreased purchasing and production power, relocation and migration, adverse psychosocial effects, and hindrance of economic growth and development. Flood prediction, management and defence strategies rely on the availability of accurate information and flood modelling. Whilst automated data gathering (by measurement and satellite) of the extent of flooding is already advanced it is least reliable in urban and physically complex geographies where often the need for precise estimation is most acute. Crowdsourced data of actual flood events is a potentially critical component of this allowing improved accuracy in situations and identifying the effects of local landscape and topography where the height of a simple kerb, or discontinuity in a boundary wall can have profound importance. Mobile 'App' based data acquisition using crowdsourcing in critical areas can combine camera records with GPS positional data and time, as well as descriptive data relating to the event. This will automatically produce a dataset, managed in ArcView GIS, with the potential for follow up calls to get more information through structured scripts for each strand. Through this local residents can provide highly detailed information that can be reflected in sophisticated flood protection models and be core to framing urban resilience strategies and optimising the effectiveness of investment. This paper will describe this pioneering approach that will develop flood event data in support of systems that will advance existing approaches such as developed in the in the UK

  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. Ac and dc motor flooding times

    International Nuclear Information System (INIS)

    Crowley, D.A.; Hinton, J.H.

    1988-01-01

    Reactor safety studies, such as the emergency cooling system (ECS) limits analyses and the probabilistic risk assessment, require that the flood-out times be calculated for the ac and dc motors at the -40 foot level. New calculations are needed because dams of an improved design have been installed between the pump room and motor room, and because updated leak rate calculations have shown that the maximum possible leak rate is larger than that which had been previously calculated. The methodology for calculating the motor flood-out times has also been improved. A computer program has been written to calculate flood-out times for various leak rates and sump pump operabilities. For ECS limits analyses, the worst case dc motor flood-out times are 161 and 297 seconds in LKC and P-areas, respectively. These times are for a 135,468 gpm leak that first flows to the motor room and all of the sump pumps are off

  2. Floods in Colorado

    Science.gov (United States)

    Follansbee, Robert; Sawyer, Leon R.

    1948-01-01

    The first records of floods in Colorado antedated the settlement of the State by about 30 years. These were records of floods on the Arkansas and Republican Rivers in 1826. Other floods noted by traders, hunters and emigrants, some of whom were on their way to the Far West, occurred in 1844 on the Arkansas River, and by inference on the South Platte River. Other early floods were those on the Purgatoire, the Lower Arkansas, and the San Juan Rivers about 1859. The most serious flood since settlement began was that on the Arkansas River during June 1921, which caused the loss of about 100 lives and an estimated property loss of $19,000,000. Many floods of lesser magnitude have occurred, and some of these have caused loss of life and very considerable property damage. Topography is the chief factor in determining the location of storms and resulting floods. These occur most frequently on the eastern slope of the Front Range. In the mountains farther west precipitation is insufficient to cause floods except during periods of melting snow, in June. In the southwestern part of the State, where precipitation during periods of melting snow is insufficient to cause floods, the severest floods yet experienced resulted from heavy rains in September 1909 and October 1911. In the eastern foothills region, usually below an altitude of about 7,500 feet and extending for a distance of about 50 miles east of the mountains, is a zone subject to rainfalls of great intensity known as cloudbursts. These cloudbursts are of short duration and are confined to very small areas. At times the intensity is so great as to make breathing difficult for those exposed to a storm. The areas of intense rainfall are so small that Weather Bureau precipitation stations have not been located in them. Local residents, being cloudburst conscious, frequently measure the rainfall in receptacles in their yards, and such records constitute the only source of information regarding the intensity. A flood

  3. Historical floods in flood frequency analysis: Is this game worth the candle?

    Science.gov (United States)

    Strupczewski, Witold G.; Kochanek, Krzysztof; Bogdanowicz, Ewa

    2017-11-01

    In flood frequency analysis (FFA) the profit from inclusion of historical information on the largest historical pre-instrumental floods depends primarily on reliability of the information, i.e. the accuracy of magnitude and return period of floods. This study is focused on possible theoretical maximum gain in accuracy of estimates of upper quantiles, that can be obtained by incorporating the largest historical floods of known return periods into the FFA. We assumed a simple case: N years of systematic records of annual maximum flows and either one largest (XM1) or two largest (XM1 and XM2) flood peak flows in a historical M-year long period. The problem is explored by Monte Carlo simulations with the maximum likelihood (ML) method. Both correct and false distributional assumptions are considered. In the first case the two-parameter extreme value models (Gumbel, log-Gumbel, Weibull) with various coefficients of variation serve as parent distributions. In the case of unknown parent distribution, the Weibull distribution was assumed as estimating model and the truncated Gumbel as parent distribution. The return periods of XM1 and XM2 are determined from the parent distribution. The results are then compared with the case, when return periods of XM1 and XM2 are defined by their plotting positions. The results are presented in terms of bias, root mean square error and the probability of overestimation of the quantile with 100-year return period. The results of the research indicate that the maximal profit of inclusion of pre-instrumental foods in the FFA may prove smaller than the cost of reconstruction of historical hydrological information.

  4. Design basis flood for nuclear power plants on river sites

    International Nuclear Information System (INIS)

    1983-01-01

    The Guide presents techniques for determining the design basis flood (DBF) to be used for siting nuclear power plants at or near non-tidal reaches of rivers and for protecting nuclear power plants against floods. Since flooding of a nuclear power plant can have repercussions on safety, the DBF is always chosen to have a very low probability of exceedance per annum. The DBF may result from one or more of the following causes: (1) Precipitation, snowmelt; (2) Failure of water control structures, either from seismic or hydrological causes or from faulty operation of these structures; (3) Channel obstruction such as landslide, ice effects, log or debris jams, and effects of vulcanism. Normally the DBF is not less than any recorded or historical flood occurrence. For flood evaluation two types of methods are discussed in this Guide: probabilistic and deterministic. Simple probabilistic methods to determine floods of such low exceedance probability have a great degree of uncertainty and are presented for use only during the site survey. However, the more sophisticated probabilistic methods, the so-called stochastic methods, may give an acceptable result, as outlined in this Guide. The preferred method of evaluating the component of the DBF due to precipitation, as described in this Guide, is the deterministic one, based on the concept of a limit to the probable maximum precipitation (PMP) and on the unit hydrograph technique. Dam failures may generate a flood substantially more severe than that due to precipitation. The methodology for evaluating these types of floods is therefore presented in this Guide. Making allowance for the possible simultaneous occurrence of two or more important flood-producing events is also discussed here. The Guide does not deal with floods caused by sabotage

  5. Submicron aerosol source apportionment of wintertime pollution in Paris, France by double positive matrix factorization (PMF2) using an aerosol chemical speciation monitor (ACSM) and a multi-wavelength Aethalometer

    International Nuclear Information System (INIS)

    Petit, J.E.; Favez, O.; Leoz-Garziandia, E.; Sciare, J.

    2014-01-01

    Online non-refractory submicron aerosol mass spectrometer (AMS) measurements in urban areas have successfully allowed the apportionment of specific sources and/or physical and chemical properties of the organic fraction. However, in order to be fully representative of PM pollution, a comprehensive source apportionment analysis is needed by taking into account all major components of submicron aerosols, creating strengthened bonds between the organic components and pollution sources. We present here a novel two-step methodology to perform such an analysis, by taking advantage of high time resolution of monitoring instruments: the aerosol chemical speciation monitor (ACSM) and the multi-wavelength absorption measurements (Aethalometer AE31) in Paris, France. As a first step, organic aerosols (OA) were de-convolved to hydrocarbon-like OA (HOA), biomass burning OA (BBOA) and oxygenated OA (OOA) with positive matrix factorization (PMF), and black carbon was de-convolved into its wood burning and fossil fuel combustion fractions. A second PMF analysis was then carried out with organic factors, BC fractions and inorganic species (nitrate, sulfate, ammonium, chloride), leading to a four-factor solution allowing highly time-resolved characterization of the major sources of PM1. Outputs of this PMF2 include two dominant combustion sources (wood burning and traffic) as well as semi-volatile and low-volatile secondary aerosols. While HOA is found to be emitted by both wood burning and traffic, the latter sources occurred to significantly contribute also to OOA. (authors)

  6. Probabilistic flood extent estimates from social media flood observations

    NARCIS (Netherlands)

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

    2017-01-01

    The increasing number and severity of floods, driven by phenomena such as urbanization, deforestation, subsidence and climate change, create a growing need for accurate and timely flood maps. In this paper we present and evaluate a method to create deterministic and probabilistic flood maps from

  7. Probabilistic flood extent estimates from social media flood observations

    NARCIS (Netherlands)

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

    2017-01-01

    The increasing number and severity of floods, driven by phenomena such as urbanization, deforestation, subsidence and climate change, creates a growing need for accurate and timely flood maps. This research focussed on creating flood maps using user generated content from Twitter. Twitter data has

  8. Mapping flood hazards under uncertainty through probabilistic flood inundation maps

    Science.gov (United States)

    Stephens, T.; Bledsoe, B. P.; Miller, A. J.; Lee, G.

    2017-12-01

    Changing precipitation, rapid urbanization, and population growth interact to create unprecedented challenges for flood mitigation and management. Standard methods for estimating risk from flood inundation maps generally involve simulations of floodplain hydraulics for an established regulatory discharge of specified frequency. Hydraulic model results are then geospatially mapped and depicted as a discrete boundary of flood extents and a binary representation of the probability of inundation (in or out) that is assumed constant over a project's lifetime. Consequently, existing methods utilized to define flood hazards and assess risk management are hindered by deterministic approaches that assume stationarity in a nonstationary world, failing to account for spatio-temporal variability of climate and land use as they translate to hydraulic models. This presentation outlines novel techniques for portraying flood hazards and the results of multiple flood inundation maps spanning hydroclimatic regions. Flood inundation maps generated through modeling of floodplain hydraulics are probabilistic reflecting uncertainty quantified through Monte-Carlo analyses of model inputs and parameters under current and future scenarios. The likelihood of inundation and range of variability in flood extents resulting from Monte-Carlo simulations are then compared with deterministic evaluations of flood hazards from current regulatory flood hazard maps. By facilitating alternative approaches of portraying flood hazards, the novel techniques described in this presentation can contribute to a shifting paradigm in flood management that acknowledges the inherent uncertainty in model estimates and the nonstationary behavior of land use and climate.

  9. Flood Risk Management In Europe: European flood regulation

    NARCIS (Netherlands)

    Hegger, D.L.T.; Bakker, M.H.; Green, C.; Driessen, Peter; Delvaux, B.; Rijswick, H.F.M.W. van; Suykens, C.; Beyers, J-C.; Deketelaere, K.; Doorn-Hoekveld, W. van; Dieperink, C.

    2013-01-01

    In Europe, water management is moving from flood defense to a risk management approach, which takes both the probability and the potential consequences of flooding into account. In this report, we will look at Directives and (non-)EU- initiatives in place to deal with flood risk in Europe indirectly

  10. Improving Global Flood Forecasting using Satellite Detected Flood Extent

    NARCIS (Netherlands)

    Revilla Romero, B.

    2016-01-01

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

  11. The Global Flood Model

    Science.gov (United States)

    Williams, P.; Huddelston, M.; Michel, G.; Thompson, S.; Heynert, K.; Pickering, C.; Abbott Donnelly, I.; Fewtrell, T.; Galy, H.; Sperna Weiland, F.; Winsemius, H.; Weerts, A.; Nixon, S.; Davies, P.; Schiferli, D.

    2012-04-01

    Recently, a Global Flood Model (GFM) initiative has been proposed by Willis, UK Met Office, Esri, Deltares and IBM. The idea is to create a global community platform that enables better understanding of the complexities of flood risk assessment to better support the decisions, education and communication needed to mitigate flood risk. The GFM will provide tools for assessing the risk of floods, for devising mitigation strategies such as land-use changes and infrastructure improvements, and for enabling effective pre- and post-flood event response. The GFM combines humanitarian and commercial motives. It will benefit: - The public, seeking to preserve personal safety and property; - State and local governments, seeking to safeguard economic activity, and improve resilience; - NGOs, similarly seeking to respond proactively to flood events; - The insurance sector, seeking to understand and price flood risk; - Large corporations, seeking to protect global operations and supply chains. The GFM is an integrated and transparent set of modules, each composed of models and data. For each module, there are two core elements: a live "reference version" (a worked example) and a framework of specifications, which will allow development of alternative versions. In the future, users will be able to work with the reference version or substitute their own models and data. If these meet the specification for the relevant module, they will interoperate with the rest of the GFM. Some "crowd-sourced" modules could even be accredited and published to the wider GFM community. Our intent is to build on existing public, private and academic work, improve local adoption, and stimulate the development of multiple - but compatible - alternatives, so strengthening mankind's ability to manage flood impacts. The GFM is being developed and managed by a non-profit organization created for the purpose. The business model will be inspired from open source software (eg Linux): - for non-profit usage

  12. Camp Marmal Flood Study

    Science.gov (United States)

    2012-03-01

    was simulated by means of a broad - crested weir built into the topography of the mesh. There is 0.5 m of freeboard and the width of the weir is 30 m...ER D C/ CH L TR -1 2- 5 Camp Marmal Flood Study Co as ta l a nd H yd ra ul ic s La bo ra to ry Jeremy A. Sharp , Steve H. Scott...Camp Marmal Flood Study Jeremy A. Sharp , Steve H. Scott, Mark R. Jourdan, and Gaurav Savant Coastal and Hydraulics Laboratory U.S. Army Engineer

  13. Oil-soluble and water-soluble BTPhens and their europium complexes in octanol/water solutions: interface crossing studied by MD and PMF simulations.

    Science.gov (United States)

    Benay, G; Wipff, G

    2013-01-31

    Bistriazinyl-phenantroline "BTPhen" ligands L display the remarkable feature to complex trivalent lanthanide and actinide ions, with a marked selectivity for the latter. We report on molecular dynamics studies of tetrasubstituted X(4)BTPhens: L(4+) (X = (+)Et(3)NCH(2)-), L(4-) (X = (-)SO(3)Ph-), and L(0) (X = CyMe(4)) and their complexes with Eu(III) in binary octanol/water solutions. Changes in free energies upon interface crossing are also calculated for typical solutes by potential of mean force PMF simulations. The ligands and their complexes partition, as expected, to either the aqueous or the oil phase, depending on the "solubilizing" group X. Furthermore, most of them are found to be surface active. The water-soluble L(4+) and L(4-) ligands and their (L)Eu(NO(3))(3) complexes adsorb at the aqueous side of the interface, more with L(4-) than with L(4+). The oil soluble ligand L(0) is not surface active in its endo-endo form but adsorbs on the oil side of the interface in its most polar endo-exo form, as well as in its protonated L(0)H(+) and complexed (L(0))Eu(NO(3))(3) states. Furthermore, comparing PMFs of the Eu(III) complexes with and without nitric acid shows that acidifying the aqueous phase has different effects, depending on the ligand charge. In particular, acid promotes the Eu(III) extraction by L(0) via the (L(0))(2)Eu(NO(3))(2+) complex, as observed experimentally. Overall, the results point to the importance of interfacial adsorption for the liquid-liquid extraction of trivalent lanthanide and actinide cations by BTPhens and analogues.

  14. Biomass burning impact on PM 2.5 over the southeastern US during 2007: integrating chemically speciated FRM filter measurements, MODIS fire counts and PMF analysis

    Directory of Open Access Journals (Sweden)

    R. J. Weber

    2010-07-01

    Full Text Available Archived Federal Reference Method (FRM Teflon filters used by state regulatory agencies for measuring PM2.5 mass were acquired from 15 sites throughout the southeastern US and analyzed for water-soluble organic carbon (WSOC, water-soluble ions and carbohydrates to investigate biomass burning contributions to fine aerosol mass. Based on over 900 filters that spanned all of 2007, levoglucosan and K+ were studied in conjunction with MODIS Aqua fire count data to compare their performances as biomass burning tracers. Levoglucosan concentrations exhibited a distinct seasonal variation with large enhancement in winter and spring and a minimum in summer, and were well correlated with fire counts, except in winter when residential wood burning contributions were significant. In contrast, K+ concentrations had no apparent seasonal trend and poor correlation with fire counts. Levoglucosan and K+ only correlated well in winter (r2=0.59 when biomass burning emissions were highest, whereas in other seasons they were not correlated due to the presence of other K+ sources. Levoglucosan also exhibited larger spatial variability than K+. Both species were higher in urban than rural sites (mean 44% higher for levoglucosan and 86% for K+. Positive Matrix Factorization (PMF was applied to analyze PM2.5 sources and four factors were resolved: biomass burning, refractory material, secondary light absorbing WSOC and secondary sulfate/WSOC. The biomass burning source contributed 13% to PM2.5 mass annually, 27% in winter, and less than 2% in summer, consistent with other souce apportionment studies based on levoglucosan, but lower in summer compared to studies based on K+.

  15. Source apportionment by PMF on elemental concentrations obtained by PIXE analysis of PM10 samples collected at the vicinity of lignite power plants and mines in Megalopolis, Greece

    International Nuclear Information System (INIS)

    Manousakas, M.; Diapouli, E.; Papaefthymiou, H.; Migliori, A.; Karydas, A.G.; Padilla-Alvarez, R.; Bogovac, M.; Kaiser, R.B.; Jaksic, M.; Bogdanovic-Radovic, I.; Eleftheriadis, K.

    2015-01-01

    Particulate matter (PM) is an important constituent of atmospheric pollution especially in areas under the influence of industrial emissions. Megalopolis is a small city of 10,000 inhabitants located in central Peloponnese in close proximity to three coal opencast mines and two lignite fired power plants. 50 PM 10 samples were collected in Megalopolis during the years 2009–11 for elemental and multivariate analysis. For the elemental analysis PIXE was used as one of the most effective techniques in APM analytical characterization. Altogether, the concentrations of 22 elements (Z = 11–33), whereas Black Carbon was also determined for each sample using a reflectometer. Factorization software was used (EPA PMF 3.0) for source apportionment analysis. The analysis revealed that major emission sources were soil dust 33% (7.94 ± 0.27 μg/m 3 ), biomass burning 19% (4.43 ± 0.27 μg/m 3 ), road dust 15% (3.63 ± 0.37 μg/m 3 ), power plant emissions 13% (3.01 ± 0.44 μg/m 3 ), traffic 12% (2.82 ± 0.37 μg/m 3 ), and sea spray 8% (1.99 ± 0.41 μg/m 3 ). Wind trajectories have suggested that metals associated with emission from the power plants came mainly from west and were connected with the locations of the lignite mines located in this area. Soil resuspension, road dust and power plant emissions increased during the warm season of the year, while traffic/secondary, sea spray and biomass burning become dominant during the cold season

  16. Source apportionment by PMF on elemental concentrations obtained by PIXE analysis of PM10 samples collected at the vicinity of lignite power plants and mines in Megalopolis, Greece

    Science.gov (United States)

    Manousakas, M.; Diapouli, E.; Papaefthymiou, H.; Migliori, A.; Karydas, A. G.; Padilla-Alvarez, R.; Bogovac, M.; Kaiser, R. B.; Jaksic, M.; Bogdanovic-Radovic, I.; Eleftheriadis, K.

    2015-04-01

    Particulate matter (PM) is an important constituent of atmospheric pollution especially in areas under the influence of industrial emissions. Megalopolis is a small city of 10,000 inhabitants located in central Peloponnese in close proximity to three coal opencast mines and two lignite fired power plants. 50 PM10 samples were collected in Megalopolis during the years 2009-11 for elemental and multivariate analysis. For the elemental analysis PIXE was used as one of the most effective techniques in APM analytical characterization. Altogether, the concentrations of 22 elements (Z = 11-33), whereas Black Carbon was also determined for each sample using a reflectometer. Factorization software was used (EPA PMF 3.0) for source apportionment analysis. The analysis revealed that major emission sources were soil dust 33% (7.94 ± 0.27 μg/m3), biomass burning 19% (4.43 ± 0.27 μg/m3), road dust 15% (3.63 ± 0.37 μg/m3), power plant emissions 13% (3.01 ± 0.44 μg/m3), traffic 12% (2.82 ± 0.37 μg/m3), and sea spray 8% (1.99 ± 0.41 μg/m3). Wind trajectories have suggested that metals associated with emission from the power plants came mainly from west and were connected with the locations of the lignite mines located in this area. Soil resuspension, road dust and power plant emissions increased during the warm season of the year, while traffic/secondary, sea spray and biomass burning become dominant during the cold season.

  17. FEMA DFIRM Base Flood Elevations

    Data.gov (United States)

    Minnesota Department of Natural Resources — The Base Flood Elevation (BFE) table is required for any digital data where BFE lines will be shown on the corresponding Flood Insurance Rate Map (FIRM). Normally,...

  18. 2013 FEMA Flood Hazard Boundaries

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The National Flood Hazard Layer (NFHL) data incorporates all Digital Flood Insurance Rate Map(DFIRM) databases published by FEMA, and any Letters Of Map Revision...

  19. 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...

  20. Base Flood Elevation (BFE) Lines

    Data.gov (United States)

    Department of Homeland Security — The Base Flood Elevation (BFE) table is required for any digital data where BFE lines will be shown on the corresponding Flood Insurance Rate Map (FIRM). Normally if...

  1. National Flood Hazard Layer (NFHL)

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The National Flood Hazard Layer (NFHL) is a compilation of GIS data that comprises a nationwide digital Flood Insurance Rate Map. The GIS data and services are...

  2. FEMA 100 year Flood Data

    Data.gov (United States)

    California Natural Resource Agency — The Q3 Flood Data product is a digital representation of certain features of FEMA's Flood Insurance Rate Map (FIRM) product, intended for use with desktop mapping...

  3. 2013 FEMA Flood Control Structures

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The National Flood Hazard Layer (NFHL) data incorporates all Digital Flood Insurance Rate Map(DFIRM) databases published by FEMA, and any Letters Of Map Revision...

  4. FEMA Q3 Flood Data

    Data.gov (United States)

    Kansas Data Access and Support Center — The Q3 Flood Data are derived from the Flood Insurance Rate Maps (FIRMS) published by the Federal Emergency Management Agency (FEMA). The file is georeferenced to...

  5. Simulated CONUS Flash Flood Climatologies from Distributed Hydrologic Models

    Science.gov (United States)

    Flamig, Z.; Gourley, J. J.; Vergara, H. J.; Kirstetter, P. E.; Hong, Y.

    2016-12-01

    This study will describe a CONUS flash flood climatology created over the period from 2002 through 2011. The MRMS reanalysis precipitation dataset was used as forcing into the Ensemble Framework For Flash Flood Forecasting (EF5). This high resolution 1-sq km 5-minute dataset is ideal for simulating flash floods with a distributed hydrologic model. EF5 features multiple water balance components including SAC-SMA, CREST, and a hydrophobic model all coupled with kinematic wave routing. The EF5/SAC-SMA and EF5/CREST water balance schemes were used for the creation of dual flash flood climatologies based on the differing water balance principles. For the period from 2002 through 2011 the daily maximum streamflow, unit streamflow, and time of peak streamflow was stored along with the minimum soil moisture. These variables are used to describe the states of the soils right before a flash flood event and the peak streamflow that was simulated during the flash flood event. The results will be shown, compared and contrasted. The resulting model simulations will be verified on basins less than 1,000-sq km with USGS gauges to ensure the distributed hydrologic models are reliable. The results will also be compared spatially to Storm Data flash flood event observations to judge the degree of agreement between the simulated climatologies and observations.

  6. Application of Artificial Neural Networks for estimating index floods

    Science.gov (United States)

    Šimor, Viliam; Hlavčová, Kamila; Kohnová, Silvia; Szolgay, Ján

    2012-12-01

    This article presents an application of Artificial Neural Networks (ANNs) and multiple regression models for estimating mean annual maximum discharge (index flood) at ungauged sites. Both approaches were tested for 145 small basins in Slovakia in areas ranging from 20 to 300 km2. Using the objective clustering method, the catchments were divided into ten homogeneous pooling groups; for each pooling group, mutually independent predictors (catchment characteristics) were selected for both models. The neural network was applied as a simple multilayer perceptron with one hidden layer and with a back propagation learning algorithm. Hyperbolic tangents were used as an activation function in the hidden layer. Estimating index floods by the multiple regression models were based on deriving relationships between the index floods and catchment predictors. The efficiencies of both approaches were tested by the Nash-Sutcliffe and a correlation coefficients. The results showed the comparative applicability of both models with slightly better results for the index floods achieved using the ANNs methodology.

  7. On the stationarity of Floods in west African rivers

    Science.gov (United States)

    NKA, B. N.; Oudin, L.; Karambiri, H.; Ribstein, P.; Paturel, J. E.

    2014-12-01

    West Africa undergoes a big change since the years 1970-1990, characterized by very low precipitation amounts, leading to low stream flows in river basins, except in the Sahelian region where the impact of human activities where pointed out to justify the substantial increase of floods in some catchments. More recently, studies showed an increase in the frequency of intense rainfall events, and according to observations made over the region, increase of flood events is also noticeable during the rainy season. Therefore, the assumption of stationarity on flood events is questionable and the reliability of flood evolution and climatic patterns is justified. In this work, we analyzed the trends of floods events for several catchments in the Sahelian and Sudanian regions of Burkina Faso. We used thirteen tributaries of large river basins (Niger, Nakambe, Mouhoun, Comoé) for which daily rainfall and flow data were collected from national hydrological and meteorological services of the country. We used Mann-Kendall and Pettitt tests to detect trends and break points in the annual time series of 8 rainfall indices and the annual maximum discharge records. We compare the trends of precipitation indices and flood size records to analyze the possible causality link between floods size and rainfall pattern. We also analyze the stationary of the frequency of flood exceeding the ten year return period level. The samples were extracted by a Peak over threshold method and the quantification of change in flood frequency was assessed by using a test developed by Lang M. (1995). The results exhibit two principal behaviors. Generally speaking, no trend is detected on catchments annual maximum discharge, but positive break points are pointed out in a group of three right bank tributaries of the Niger river that are located in the sahelian region between 300mm to 650mm. These same catchments show as well an increase of the yearly number of flood greater than the ten year flood since

  8. Multivariate pluvial flood damage models

    International Nuclear Information System (INIS)

    Van Ootegem, Luc; Verhofstadt, Elsy; Van Herck, Kristine; Creten, Tom

    2015-01-01

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

  9. Multivariate pluvial flood damage models

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-09-15

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

  10. The Kassel concept for river flood defence

    Energy Technology Data Exchange (ETDEWEB)

    Toensmann, F. [Kassel Univ. (Germany). Dept. of Hydraulic and Water-Resources Engineering

    2000-07-01

    Following an introduction referring to the history, the regulation of ''interference and compensation'' and the ''sustainable development'' as the foundation of future-oriented flood defence concepts are dealt with. The position of science and technology with respect to the employed planning methods: Models for the determination of spatial and temporal distribution of maximum precipitation, river basin models, methods for water level computation, benefit/cost analysis and environmental assessment are described and evaluated. Thereafter the Kassel Concept for River Flood Defence is presented. The basic principle is a mosaic of de-central, semi-central and central measures with reference to the specific project which are economically eligible and environment-compatible. (orig.)

  11. Floods in a changing climate

    Science.gov (United States)

    Theresa K. Andersen; Marshall J. Shepherd

    2013-01-01

    Atmospheric warming and associated hydrological changes have implications for regional flood intensity and frequency. Climate models and hydrological models have the ability to integrate various contributing factors and assess potential changes to hydrology at global to local scales through the century. This survey of floods in a changing climate reviews flood...

  12. Flood extent mapping for Namibia using change detection and thresholding with SAR

    International Nuclear Information System (INIS)

    Long, Stephanie; Fatoyinbo, Temilola E; Policelli, Frederick

    2014-01-01

    A new method for flood detection change detection and thresholding (CDAT) was used with synthetic aperture radar (SAR) imagery to delineate the extent of flooding for the Chobe floodplain in the Caprivi region of Namibia. This region experiences annual seasonal flooding and has seen a recent renewal of severe flooding after a long dry period in the 1990s. Flooding in this area has caused loss of life and livelihoods for the surrounding communities and has caught the attention of disaster relief agencies. There is a need for flood extent mapping techniques that can be used to process images quickly, providing near real-time flooding information to relief agencies. ENVISAT/ASAR and Radarsat-2 images were acquired for several flooding seasons from February 2008 to March 2013. The CDAT method was used to determine flooding from these images and includes the use of image subtraction, decision-based classification with threshold values, and segmentation of SAR images. The total extent of flooding determined for 2009, 2011 and 2012 was about 542 km 2 , 720 km 2 , and 673 km 2 respectively. Pixels determined to be flooded in vegetation were typically <0.5% of the entire scene, with the exception of 2009 where the detection of flooding in vegetation was much greater (almost one third of the total flooded area). The time to maximum flooding for the 2013 flood season was determined to be about 27 days. Landsat water classification was used to compare the results from the new CDAT with SAR method; the results show good spatial agreement with Landsat scenes. (paper)

  13. Study of flood defense structural measures priorities using Compromise Programming technique

    Science.gov (United States)

    Lim, D.; Jeong, S.

    2017-12-01

    Recent climate change of global warming has led to the frequent occurrence of heavy regional rainfalls. As such, inundation vulnerability increases in urban areas with high population density due to the low runoff carrying capacity. This study selects a sample area (Janghang-eup, the Republic of Korea), which is one of the most vulnerable areas to flooding, analyzing the urban flood runoff model (XP-SWMM) and using the MCDM (Multi-Criteria Decision Making) technique to establish flood protection structural measures. To this end, we compare the alternatives and choose the optimal flood defense measure: our model is utilized with three flood prevention structural measures; (i) drainage pipe construction; (ii) water detention; and (iii) flood pumping station. Dividing the target area into three small basins, we propose flood evaluations for an inundation decrease by studying the flooded area, the maximum inundation depth, the damaged residential area, and the construction cost. In addition, Compromise Programming determines the priority of the alternatives. As a consequent, this study suggests flood pumping station for Zone 1 and drainage pipe construction for Zone 2 and Zone 3, respectively, as the optimal flood defense alternative. Keywords : MCDM; Compromise Programming; Urban Flood Prevention; This research was supported by a grant [MPSS-DP-2013-62] through the Disaster and Safety Management Institute funded by Ministry of Public Safety and Security of Korean government.

  14. Flood Inundation Mapping in the Logone Floodplain from Multi Temporal Landsat ETM+Imagery

    Science.gov (United States)

    Jung, Hahn Chul; Alsdorf, Douglas E.; Moritz, Mark; Lee, Hyongki; Vassolo, Sara

    2011-01-01

    Yearly flooding in the Logone floodplain makes an impact on agricultural, pastoral, and fishery systems in the Lake Chad Basin. Since the flooding extent and depth are highly variable, flood inundation mapping helps us make better use of water resources and prevent flood hazards in the Logone floodplain. The flood maps are generated from 33 multi temporal Landsat Enhanced Thematic Mapper Plus (ETM+) during three years 2006 to 2008. Flooded area is classified using a short-wave infrared band whereas open water is classified by Iterative Self-organizing Data Analysis (ISODATA) clustering. The maximum flooding extent in the study area increases up to approximately 5.8K km2 in late October 2008. The study also provides strong correlation of the flooding extents with water height variations in both the floodplain and the river based on a second polynomial regression model. The water heights are from ENIVSAT altimetry in the floodplain and gauge measurements in the river. Coefficients of determination between flooding extents and water height variations are greater than 0.91 with 4 to 36 days in phase lag. Floodwater drains back to the river and to the northeast during the recession period in December and January. The study supports understanding of the Logone floodplain dynamics in detail of spatial pattern and size of the flooding extent and assists the flood monitoring and prediction systems in the catchment.

  15. A non-stationary cost-benefit based bivariate extreme flood estimation approach

    Science.gov (United States)

    Qi, Wei; Liu, Junguo

    2018-02-01

    Cost-benefit analysis and flood frequency analysis have been integrated into a comprehensive framework to estimate cost effective design values. However, previous cost-benefit based extreme flood estimation is based on stationary assumptions and analyze dependent flood variables separately. A Non-Stationary Cost-Benefit based bivariate design flood estimation (NSCOBE) approach is developed in this study to investigate influence of non-stationarities in both the dependence of flood variables and the marginal distributions on extreme flood estimation. The dependence is modeled utilizing copula functions. Previous design flood selection criteria are not suitable for NSCOBE since they ignore time changing dependence of flood variables. Therefore, a risk calculation approach is proposed based on non-stationarities in both marginal probability distributions and copula functions. A case study with 54-year observed data is utilized to illustrate the application of NSCOBE. Results show NSCOBE can effectively integrate non-stationarities in both copula functions and marginal distributions into cost-benefit based design flood estimation. It is also found that there is a trade-off between maximum probability of exceedance calculated from copula functions and marginal distributions. This study for the first time provides a new approach towards a better understanding of influence of non-stationarities in both copula functions and marginal distributions on extreme flood estimation, and could be beneficial to cost-benefit based non-stationary bivariate design flood estimation across the world.

  16. Math Fights Flooding

    NARCIS (Netherlands)

    Besseling, Niels; Bokhove, Onno; Kolechkina, Alla; Molenaar, Jaap; van Nooyen, Ronald; Rottschäfer, Vivi; Stein, Alfred; Stoorvogel, Anton

    2008-01-01

    Due to climate changes that are expected in the coming years, the characteristics of the rainfall will change. This can potentially cause flooding or have negative influences on agriculture and nature. In this research, we study the effects of this change in rainfall and investigate what can be done

  17. Flood model for Brazil

    Science.gov (United States)

    Palán, Ladislav; Punčochář, Petr

    2017-04-01

    Looking on the impact of flooding from the World-wide perspective, in last 50 years flooding has caused over 460,000 fatalities and caused serious material damage. Combining economic loss from ten costliest flood events (from the same period) returns a loss (in the present value) exceeding 300bn USD. Locally, in Brazil, flood is the most damaging natural peril with alarming increase of events frequencies as 5 out of the 10 biggest flood losses ever recorded have occurred after 2009. The amount of economic and insured losses particularly caused by various flood types was the key driver of the local probabilistic flood model development. Considering the area of Brazil (being 5th biggest country in the World) and the scattered distribution of insured exposure, a domain covered by the model was limited to the entire state of Sao Paolo and 53 additional regions. The model quantifies losses on approx. 90 % of exposure (for regular property lines) of key insurers. Based on detailed exposure analysis, Impact Forecasting has developed this tool using long term local hydrological data series (Agencia Nacional de Aguas) from riverine gauge stations and digital elevation model (Instituto Brasileiro de Geografia e Estatística). To provide most accurate representation of local hydrological behaviour needed for the nature of probabilistic simulation, a hydrological data processing focused on frequency analyses of seasonal peak flows - done by fitting appropriate extreme value statistical distribution and stochastic event set generation consisting of synthetically derived flood events respecting realistic spatial and frequency patterns visible in entire period of hydrological observation. Data were tested for homogeneity, consistency and for any significant breakpoint occurrence in time series so the entire observation or only its subparts were used for further analysis. The realistic spatial patterns of stochastic events are reproduced through the innovative use of d-vine copula

  18. 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...

  19. Hydrological forecast of maximal water level in Lepenica river basin and flood control measures

    Directory of Open Access Journals (Sweden)

    Milanović Ana

    2006-01-01

    Full Text Available Lepenica river basin territory has became axis of economic and urban development of Šumadija district. However, considering Lepenica River with its tributaries, and their disordered river regime, there is insufficient of water for water supply and irrigation, while on the other hand, this area is suffering big flood and torrent damages (especially Kragujevac basin. The paper presents flood problems in the river basin, maximum water level forecasts, and flood control measures carried out until now. Some of the potential solutions, aiming to achieve the effective flood control, are suggested as well.

  20. FEH Local: Improving flood estimates using historical data

    Directory of Open Access Journals (Sweden)

    Prosdocimi Ilaria

    2016-01-01

    Full Text Available The traditional approach to design flood estimation (for example, to derive the 100-year flood is to apply a statistical model to time series of peak river flow measured by gauging stations. Such records are typically not very long, for example in the UK only about 10% of the stations have records that are more than 50 years in length. Along-explored way to augment the data available from a gauging station is to derive information about historical flood events and paleo-floods, which can be obtained from careful exploration of archives, old newspapers, flood marks or other signs of past flooding that are still discernible in the catchment, and the history of settlements. The inclusion of historical data in flood frequency estimation has been shown to substantially reduce the uncertainty around the estimated design events and is likely to provide insight into the rarest events which might have pre-dated the relatively short systematic records. Among other things, the FEH Local project funded by the Environment Agency aims to develop methods to easily incorporate historical information into the standard method of statistical flood frequency estimation in the UK. Different statistical estimation procedures are explored, namely maximum likelihood and partial probability weighted moments, and the strengths and weaknesses of each method are investigated. The project assesses the usefulness of historical data and aims to provide practitioners with useful guidelines to indicate in what circumstances the inclusion of historical data is likely to be beneficial in terms of reducing both the bias and the variability of the estimated flood frequency curves. The guidelines are based on the results of a large Monte Carlo simulation study, in which different estimation procedures and different data availability scenarios are studied. The study provides some indication of the situations under which different estimation procedures might give a better performance.

  1. Credal Networks under Maximum Entropy

    OpenAIRE

    Lukasiewicz, Thomas

    2013-01-01

    We apply the principle of maximum entropy to select a unique joint probability distribution from the set of all joint probability distributions specified by a credal network. In detail, we start by showing that the unique joint distribution of a Bayesian tree coincides with the maximum entropy model of its conditional distributions. This result, however, does not hold anymore for general Bayesian networks. We thus present a new kind of maximum entropy models, which are computed sequentially. ...

  2. 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 ...

  3. GIS Support for Flood Rescue

    DEFF Research Database (Denmark)

    Liang, Gengsheng; Mioc, Darka; Anton, François

    2007-01-01

    Under flood events, the ground traffic is blocked in and around the flooded area due to damages to roads and bridges. The traditional transportation network may not always help people to make a right decision for evacuation. In order to provide dynamic road information needed for flood rescue, we...... to retrieve the shortest and safest route in Fredericton road network during flood event. It enables users to make a timely decision for flood rescue. We are using Oracle Spatial to deal with emergency situations that can be applied to other constrained network applications as well....... developed an adaptive web-based transportation network application using Oracle technology. Moreover, the geographic relationships between the road network and flood areas are taken into account. The overlay between the road network and flood polygons is computed on the fly. This application allows users...

  4. Numerical simulation of flood barriers

    Science.gov (United States)

    Srb, Pavel; Petrů, Michal; Kulhavý, Petr

    This paper deals with testing and numerical simulating of flood barriers. The Czech Republic has been hit by several very devastating floods in past years. These floods caused several dozens of causalities and property damage reached billions of Euros. The development of flood measures is very important, especially for the reduction the number of casualties and the amount of property damage. The aim of flood control measures is the detention of water outside populated areas and drainage of water from populated areas as soon as possible. For new flood barrier design it is very important to know its behaviour in case of a real flood. During the development of the barrier several standardized tests have to be carried out. Based on the results from these tests numerical simulation was compiled using Abaqus software and some analyses were carried out. Based on these numerical simulations it will be possible to predict the behaviour of barriers and thus improve their design.

  5. Flood risk on the Black sea coast of Russia

    Science.gov (United States)

    Alekseevsky, Nikolay; Magritsky, Dmitry; Koltermann, Peter; Krylenko, Inna; Umina, Natalya; Aybulatov, Denis; Efremova, Natalya; Lebedeva, Seraphima

    2013-04-01

    The data of unique database "Floods in the coastal zones of Europeans part of Russia", developed by authors, are shown, that frequency of floods and damage in the coastal zones are growing. There is most dangerous situation on the Black sea coast of Russia. Here the main part of settlements, resorts and industry is situated in the river valleys and mouths. All main roads and pipelines cross the river channels. The Black sea rivers have flood regime with high intensity of flood formations and huge destructive flood power. Despite prevalence of floods during the cold period of year the most part of high floods in 100 years of supervision was noted here in the summer-fall (65% in July-October). Usually they were induced by the showers connected with passing of powerful cyclones, atmospheric fronts, and water tornadoes. The insignificant part of floods was connected with snow melting, backwater phenomena, showers in the cities and dam breaks. Thus shower induced floods here are the most widespread and destructive. Usually they arise within two-three watersheds simultaneously. Formation catastrophic heavy rain flood is possible on any site of a river valley of the Black Sea coast. The wave of a high water moves with very high speed, carrying a large number of deposits and garbage. To the mouth the flood can be transformed into debris flow. The water levels during a high water period rise on 3-6 m in the channels, and up to 11-12 m in the river canyons; the maximum depths of flow on the floodplains are 3 m and more. Flooding depths, induced by slope streams, can be to 0,5 m and higher. Flooding proceeds only some hours. After that water rather quickly flows down from a floodplains to the bed of the rivers and into the sea, leaving traces of destructions, a powerful layer of deposits (to 10-20 cm and more) and garbage. In the mouth river deposits quite often form the river mouth bar which is washed away during next storms. The damage from river floods on the Black Sea

  6. Regional flood frequency analysis in the KwaZulu-Natal province, South Africa, using the index-flood method

    DEFF Research Database (Denmark)

    Kjeldsen, Thomas Rødding; Smithers, J.C.; Schulze, R.E.

    2002-01-01

    A regional frequency analysis of annual maximum series (AMS) of flood flows from relatively unregulated rivers in the KwaZulu-Natal province of South Africa has been conducted, including identification of homogeneous regions and suitable regional frequency distributions for the regions. The study...

  7. Citizen involvement in flood risk governance: flood groups and networks

    Directory of Open Access Journals (Sweden)

    Twigger-Ross Clare

    2016-01-01

    Full Text Available Over the past decade has been a policy shift withinUK flood risk management towards localism with an emphasis on communities taking ownership of flood risk. There is also an increased focus on resilience and, more specifically, on community resilience to flooding. This paper draws on research carried out for UK Department for Environment Food and Rural Affairs to evaluate the Flood Resilience Community Pathfinder (FRCP scheme in England. Resilience is conceptualised as multidimensional and linked to exisiting capacities within a community. Creating resilience to flooding is an ongoing process of adaptation, learning from past events and preparing for future risks. This paper focusses on the development of formal and informal institutions to support improved flood risk management: institutional resilience capacity. It includes new institutions: e.g. flood groups, as well as activities that help to build inter- and intra- institutional resilience capacity e.g. community flood planning. The pathfinder scheme consisted of 13 projects across England led by local authorities aimed at developing community resilience to flood risk between 2013 – 2015. This paper discusses the nature and structure of flood groups, the process of their development, and the extent of their linkages with formal institutions, drawing out the barriers and facilitators to developing institutional resilience at the local level.

  8. Diurnal and seasonal trends and source apportionment of redox-active metals in Los Angeles using a novel online metal monitor and Positive Matrix Factorization (PMF)

    Science.gov (United States)

    Mousavi, Amirhosein; Sowlat, Mohammad H.; Sioutas, Constantinos

    2018-02-01

    In the present study, we identified the sources of four redox-active metals, including Iron (Fe), Chromium (Cr), Cupper (Cu), and Manganese (Mn) and quantified the contribution of these sources to PM2.5 concentrations in central Los Angeles, California, by employing time-resolved measurements (i.e., a time resolution of 2 h) with a recently developed online metal monitor and Positive Matrix Factorization (PMF). Size distribution of ambient PM (14 nm-10 μm) was measured using the Scanning Mobility Particle Sizer (SMPS) and Optical Particle Sizer (OPS). Auxiliary variables were also collected, including elemental (EC) and organic carbon (OC), gaseous pollutants (NO2 and O3), meteorological parameters (including relative humidity (RH) and temperature), and traffic data (for heavy- (HDVs) and light-duty vehicles (LDVs)). A 4-factor solution was found to be optimum for the chemically-speciated dataset, whereas a 5-factor solution appeared to be most plausible for the size distribution data. The factors included fresh traffic, soil/road dust, urban background aerosol, secondary aerosol, and nucleation (only resolved for the size distribution data). Fresh traffic was the major contributor to Fe and Cu concentrations, whereas Cr was mostly found in the urban background aerosol (reflecting a mixture of small local sources as well as aged traffic emissions), and Mn mostly came from both soil/road dust and was to a lesser degree found in urban background aerosol. Secondary aerosol did not contribute to the concentrations of any of these metals, but was associated with very high loading of OC, as expected. Even though the urban background aerosol and secondary aerosol appeared to be characterized by "aged" particles and have a rather homogeneous spatial distribution, the reactions and processes involved in their formation are entirely different. Our results provide insights into the sources of redox-active metals in central Los Angeles. They also underscore the benefits of

  9. Flooding PSA by considering the operating experience data of Korean PWRs

    International Nuclear Information System (INIS)

    Choi, Sun Yeong; Yang, Joon Eon

    2007-01-01

    The existing flooding Probabilistic Safety Analysis (PSA) was updated to reflect the Korean plant specific operating experience data into the flooding frequency to improve the PSA quality. Both the Nuclear Power Experience (NPE) database and the Korea Nuclear PIPE Failure Database (NuPIPE) databases were used in this study, and from these databases, only the Pressurized Water Reactor (PWR) data were used for the flooding frequencies of the flooding areas in the primary auxiliary building. With these databases and a Bayesian method, the flooding frequencies for the flooding areas were estimated. Subsequently, the Core Damage Frequency (CDF) for the flooding PSA of the UlChiN (UCN) unit 3 and 4 plants based on the Korean Standard Nuclear power Plant (KSNP) internal full-power PSA model was recalculated. The evaluation results showed that sixteen flooding events are potentially significant according to the screening criterion, while there were two flooding events exceeding the screening criterion of the existing UCN 3 and 4 flooding PSA. The result was compared with two kinds of cases: 1) the flooding frequency and CDF from the method of the existing flooding PSA with the PWR and Boiled Water Reactor (BWR) data of the NPE database and the Maximum Likelihood Estimate (MLE) method and 2) the flooding frequency and CDF with the NPE database (PWR and BWR data), NuPIPE database, and a Bayesian method. From the comparison, a difference in CDF results was revealed more clearly between the CDF from this study and case 2) than between case 1) and case 2). That is, the number of flooding events exceeding the screen criterion further increased when only the PWR data were used for the primary auxiliary building than when the Korean specific data were used

  10. Floods and tsunamis.

    Science.gov (United States)

    Llewellyn, Mark

    2006-06-01

    Floods and tsunamis cause few severe injuries, but those injuries can overwhelm local areas, depending on the magnitude of the disaster. Most injuries are extremity fractures, lacerations, and sprains. Because of the mechanism of soft tissue and bone injuries, infection is a significant risk. Aspiration pneumonias are also associated with tsunamis. Appropriate precautionary interventions prevent communicable dis-ease outbreaks. Psychosocial health issues must be considered.

  11. Flood potential of Fortymile Wash and its principal southwestern tributaries, Nevada Test Site, Southern Nevada

    International Nuclear Information System (INIS)

    Squires, R.R.; Young, R.L.

    1984-01-01

    Flood hazards for a 9-mile reach of Fortymile Wash and its principal southwestern tributaries - Busted Butte, Drill Hole, and Yucca Washes - were evaluated to aid in determining possible sites for the storage of high-level radioactive wastes on the Nevada Test Site. Data from 12 peak-flow gaging stations adjacent to the Test Site were used to develop regression relations that would permit an estimation of the magnitude of the 100- and 500-year flood peaks (Q 100 and Q 500 ), in cubic feet per second. The resulting equations are: Q 100 = 482A 0 565 and Q 500 = 2200A 0 571 , where A is the tributary drainage area, in square miles. The estimate of the regional maximum flood was based on data from extreme floods elsewhere in Nevada and in surrounding states. Among seven cross sections on Fortymile Wash, the estimated maximum depths of the 100-year, 500-year, and regional maximum floods are 8, 11, and 29 feet, respectively. At these depths, flood water would remain within the deeply incised channel of the wash. Mean flow velocities would be as great as 9, 14, and 28 feet per second for the three respective flood magnitudes. The study shows that Busted Butte and Drill Hole Washes (9 and 11 cross sections, respectively) would have water depths of up to at least 4 feet and mean flow velocities of up to at least 8 feet per second during a 100-year flood. A 500-year flood would exceed stream-channel capacities at several places, with depths to 10 feet and mean flow velocities to 11 feet per second. The regional maximum flood would inundate sizeable areas in central parts of the two watersheds. At Yucca Wash (5 cross sections), the 100-year, 500-year, and regional maximum floods would remain within the stream channel. Maximum flood depths would be about 5, 9, and 23 feet and mean velocities about 9, 12, and 22 feet per second, respectively, for the three floods

  12. Quantification of Uncertainty in the Flood Frequency Analysis

    Science.gov (United States)

    Kasiapillai Sudalaimuthu, K.; He, J.; Swami, D.

    2017-12-01

    Flood frequency analysis (FFA) is usually carried out for planning and designing of water resources and hydraulic structures. Owing to the existence of variability in sample representation, selection of distribution and estimation of distribution parameters, the estimation of flood quantile has been always uncertain. Hence, suitable approaches must be developed to quantify the uncertainty in the form of prediction interval as an alternate to deterministic approach. The developed framework in the present study to include uncertainty in the FFA discusses a multi-objective optimization approach to construct the prediction interval using ensemble of flood quantile. Through this approach, an optimal variability of distribution parameters is identified to carry out FFA. To demonstrate the proposed approach, annual maximum flow data from two gauge stations (Bow river at Calgary and Banff, Canada) are used. The major focus of the present study was to evaluate the changes in magnitude of flood quantiles due to the recent extreme flood event occurred during the year 2013. In addition, the efficacy of the proposed method was further verified using standard bootstrap based sampling approaches and found that the proposed method is reliable in modeling extreme floods as compared to the bootstrap methods.

  13. Numerical Simulation of Flood Levels for Tropical Rivers

    International Nuclear Information System (INIS)

    Mohammed, Thamer Ahmed; Said, Salim; Bardaie, Mohd Zohadie; Basri, Shah Nor

    2011-01-01

    Flood forecasting is important for flood damage reduction. As a result of advances in the numerical methods and computer technologies, many mathematical models have been developed and used for hydraulic simulation of the flood. These simulations usually include the prediction of the flood width and depth along a watercourse. Results obtained from the application of hydraulic models will help engineers to take precautionary measures to minimize flood damage. Hydraulic models were used to simulate the flood can be classified into dynamic hydraulic models and static hydraulic models. The HEC-2 static hydraulic model was used to predict water surface profiles for Linggi river and Langat river in Malaysia. The model is based on the numerical solution of the one dimensional energy equation of the steady gradually varied flow using the iteration technique. Calibration and verification of the HEC-2 model were conducted using the recorded data for both rivers. After calibration, the model was applied to predict the water surface profiles for Q10, Q30, and Q100 along the watercourse of the Linggi river. The water surface profile for Q200 for Langat river was predicted. The predicted water surface profiles were found in agreement with the recorded water surface profiles. The value of the maximum computed absolute error in the predicted water surface profile was found to be 500 mm while the minimum absolute error was 20 mm only.

  14. Floods in the Niger basin - analysis and attribution

    Science.gov (United States)

    Aich, V.; Koné, B.; Hattermann, F. F.; Müller, E. N.

    2014-08-01

    This study addresses the increasing flood risk in the Niger basin and assesses the damages that arise from flooding. Statistics from three different sources (EM-DAT, Darthmouth Flood Observatory, NatCat Munich RE) on people affected by floods show positive trends for the entire basin beginning in the 1980s. An assessment of four subregions across the Niger basin indicates even exponential trends for the Sahelian and Sudanian regions. These positive trends for flooding damage match up to a time series of annual maximum discharge (AMAX): the strongest trends in AMAX are detected in the Sahelian and Sudanian regions, where the population is also increasing the fastest and vulnerability generally appears to be very high. The joint effect of these three factors can possibly explain the exponential increase in people affected by floods in these subregions. In a second step, the changes in AMAX are attributed to changes in precipitation and land use via a data-based approach within a hypothesis-testing framework. Analysis of rainfall, heavy precipitation and the runoff coefficient shows a coherent picture of a return to wet conditions in the basin, which we identify as the main driver of the increase in AMAX in the Niger basin. The analysis of flashiness (using the Richards-Baker Index) and the focus on the "Sahel Paradox" of the Sahelian region reveal an additional influence of land-use change, but it seems minor compared to the increase in precipitation.

  15. Flood potential of Topopah Wash and tributaries, eastern part of Jackass Flats, Nevada Test Site, southern Nevada

    International Nuclear Information System (INIS)

    Christensen, R.C.; Spahr, N.E.

    1980-01-01

    Guidelines for evaluating potential surface facilities to be used for the storage of high-level radioactive wastes on the Nevada Test Site in southern Nevada include the consideration of the potential for flooding. Those floods that are considered to constitute the principal flood hazards for these facilities are the 100- and 500-year floods, and the maximum potential flood. Flood-prone areas for the three floods with present natural-channel conditions were defined for the eastern part of Jackass Flats in the southwestern part of the Nevada Test Site. The 100-year flood-prone areas would closely parallel most stream channels with very few occurrences of out-of-bank flooding between adjacent channels. Out-of-bank flooding would occur at depths of less than 2 feet with mean velocities as much as 7 feet per second. Channel flood depths would range from 1 to 9 feet and mean velocities would range from 3 to 9 feet per second. The 500-year flood would exceed the discharge capacities of all channels except for Topopah Wash and some channels in the upstream reaches of a few tributaries. Out-of-bank flows between adjacent channels would occur at depths as much as 3 feet with mean velocities of more than 7 feet per second. Channel flood depths would range from 1 to 12 feet and mean velocities would range from 3 to 13 feet per second. The maximum potential flood would inundate most of the study area. Excluded areas would be those located immediately east of the upstream reach of Topopah Wash and between upstream channel reaches of some tributaries. Out-of-bank flows between adjacent channels would occur at depths as much as 5 feet with mean velocities as much s 13 feet per second. Channel flood depth would range from 2 to 23 feet and mean velocities would range from 4 to 26 feet per second

  16. Large floods and climatic change during the Holocene on the Ara River, Central Japan

    Science.gov (United States)

    Grossman, Michael J.

    2001-07-01

    A reconstruction of part of the Holocene large flood record for the Ara River in central Japan is presented. Maximum intermediate gravel-size dimensions of terrace and modern floodplain gravels were measured along an 18-km reach of the river and were used in tractive force equations to estimate minimum competent flood depths. Results suggest that the magnitudes of large floods on the Ara River have varied in a non-random fashion since the end of the last glacial period. Large floods with greater magnitudes occurred during the warming period of the post-glacial and the warmer early to middle Holocene (to ˜5500 years BP). A shift in the magnitudes of large floods occurred ˜5500-5000 years BP. From this time, during the cooler middle to late Holocene, large floods generally had lower magnitudes. In the modern period, large flood magnitudes are the largest in the data set. As typhoons are the main cause of large floods on the Ara River in the modern record, the variation in large flood magnitudes suggests that the incidence of typhoon visits to the central Japan changed as the climate changed during the Holocene. Further, significant dates in the large flood record on the Ara River correspond to significant dates in Europe and the USA.

  17. Characterisation of seasonal flood types according to timescales in mixed probability distributions

    Science.gov (United States)

    Fischer, Svenja; Schumann, Andreas; Schulte, Markus

    2016-08-01

    When flood statistics are based on annual maximum series (AMS), the sample often contains flood peaks, which differ in their genesis. If the ratios among event types change over the range of observations, the extrapolation of a probability distribution function (pdf) can be dominated by a majority of events that belong to a certain flood type. If this type is not typical for extraordinarily large extremes, such an extrapolation of the pdf is misleading. To avoid this breach of the assumption of homogeneity, seasonal models were developed that differ between winter and summer floods. We show that a distinction between summer and winter floods is not always sufficient if seasonal series include events with different geneses. Here, we differentiate floods by their timescales into groups of long and short events. A statistical method for such a distinction of events is presented. To demonstrate their applicability, timescales for winter and summer floods in a German river basin were estimated. It is shown that summer floods can be separated into two main groups, but in our study region, the sample of winter floods consists of at least three different flood types. The pdfs of the two groups of summer floods are combined via a new mixing model. This model considers that information about parallel events that uses their maximum values only is incomplete because some of the realisations are overlaid. A statistical method resulting in an amendment of statistical parameters is proposed. The application in a German case study demonstrates the advantages of the new model, with specific emphasis on flood types.

  18. The development of flood map in Malaysia

    Science.gov (United States)

    Zakaria, Siti Fairus; Zin, Rosli Mohamad; Mohamad, Ismail; Balubaid, Saeed; Mydin, Shaik Hussein; MDR, E. M. Roodienyanto

    2017-11-01

    In Malaysia, flash floods are common occurrences throughout the year in flood prone areas. In terms of flood extent, flash floods affect smaller areas but because of its tendency to occur in densely urbanized areas, the value of damaged property is high and disruption to traffic flow and businesses are substantial. However, in river floods especially the river floods of Kelantan and Pahang, the flood extent is widespread and can extend over 1,000 square kilometers. Although the value of property and density of affected population is lower, the damage inflicted by these floods can also be high because the area affected is large. In order to combat these floods, various flood mitigation measures have been carried out. Structural flood mitigation alone can only provide protection levels from 10 to 100 years Average Recurrence Intervals (ARI). One of the economically effective non-structural approaches in flood mitigation and flood management is using a geospatial technology which involves flood forecasting and warning services to the flood prone areas. This approach which involves the use of Geographical Information Flood Forecasting system also includes the generation of a series of flood maps. There are three types of flood maps namely Flood Hazard Map, Flood Risk Map and Flood Evacuation Map. Flood Hazard Map is used to determine areas susceptible to flooding when discharge from a stream exceeds the bank-full stage. Early warnings of incoming flood events will enable the flood victims to prepare themselves before flooding occurs. Properties and life's can be saved by keeping their movable properties above the flood levels and if necessary, an early evacuation from the area. With respect to flood fighting, an early warning with reference through a series of flood maps including flood hazard map, flood risk map and flood evacuation map of the approaching flood should be able to alert the organization in charge of the flood fighting actions and the authority to

  19. Flooding of a large, passive, pressure-tube LWR

    Energy Technology Data Exchange (ETDEWEB)

    Hejzlar, P.; Todreas, N.E.; Driscoll, M.J. [Massachusetts Institute of Technology, Cambridge, MA (United States)

    1995-09-01

    A reactor concept has been developed which can survive LOCA without scram and without replenishing primary coolant inventory. The proposed concept is a pressure tube type reactor similar to CANDU reactors, but differing in three key aspects: (1) a solid SiC-coated graphite fuel matrix is used in place of fuel pin bundles, (2) the heavy water coolant in the pressure tubes is replaced by light water, and (3) the calandria tank contains a low pressure gas instead of heavy water moderator. The gas displaces the light water from the calandria during normal operation, while during loss of coolant or loss of heat sink accidents, it allows passive calandria flooding. This paper describes the thermal hydraulic characteristics of the gravity driven calandria flooding process. Flooding the calandria space with light water is a unique and very important feature of the proposed pressure-tube LWR concept. The flooding of the top row of fuel channels must be accomplished fast enough so that none of the critical components of the fuel channel exceed their design limits. The flooding process has been modeled and shown to be rapid enough to maintain all components within their design limits. Two other considerations are important. The thermal shock experienced by the calandria and pressure tubes has been evaluated and shown to be within acceptable bounds. Finally, although complete flooding renders the reactor deeply subcritical, various steam/water densities can be hypothesized to be present during the flooding process which could cause reactivity to increase from the initially voided calandria case. One such hypothesis which leads to the maximum possible density of the steam/water mixture in the still unflooded calandria space is entrainment from the free surface. It is shown that the steam/water mixture density yielding the maximum reactivity peak cannot be achieved by entrainment because it exceeds thermohydraulically attainable densities of steam/water by an order of magnitude.

  20. Swiss Re Global Flood Hazard Zones: Know your flood risk

    Science.gov (United States)

    Vinukollu, R. K.; Castaldi, A.; Mehlhorn, J.

    2012-12-01

    Floods, among all natural disasters, have a great damage potential. On a global basis, there is strong evidence of increase in the number of people affected and economic losses due to floods. For example, global insured flood losses have increased by 12% every year since 1970 and this is expected to further increase with growing exposure in the high risk areas close to rivers and coastlines. Recently, the insurance industry has been surprised by the large extent of losses, because most countries lack reliable hazard information. One example has been the 2011 Thailand floods where millions of people were affected and the total economic losses were 30 billion USD. In order to assess the flood risk across different regions and countries, the flood team at Swiss Re based on a Geomorphologic Regression approach, developed in house and patented, produced global maps of flood zones. Input data for the study was obtained from NASA's Shuttle Radar Topographic Mission (SRTM) elevation data, Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Global Digital Elevation Model (GDEM) and HydroSHEDS. The underlying assumptions of the approach are that naturally flowing rivers shape their channel and flood plain according to basin inherent forces and characteristics and that the flood water extent strongly depends on the shape of the flood plain. On the basis of the catchment characteristics, the model finally calculates the probability of a location to be flooded or not for a defined return period, which in the current study was set to 100 years. The data is produced at a 90-m resolution for latitudes 60S to 60N. This global product is now used in the insurance industry to inspect, inform and/or insure the flood risk across the world.

  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. Public perception of flood risks, flood forecasting and mitigation

    Directory of Open Access Journals (Sweden)

    M. Brilly

    2005-01-01

    Full Text Available A multidisciplinary and integrated approach to the flood mitigation decision making process should provide the best response of society in a flood hazard situation including preparation works and post hazard mitigation. In Slovenia, there is a great lack of data on social aspects and public response to flood mitigation measures and information management. In this paper, two studies of flood perception in the Slovenian town Celje are represented. During its history, Celje was often exposed to floods, the most recent serious floods being in 1990 and in 1998, with a hundred and fifty return period and more than ten year return period, respectively. Two surveys were conducted in 1997 and 2003, with 157 participants from different areas of the town in the first, and 208 in the second study, aiming at finding the general attitude toward the floods. The surveys revealed that floods present a serious threat in the eyes of the inhabitants, and that the perception of threat depends, to a certain degree, on the place of residence. The surveys also highlighted, among the other measures, solidarity and the importance of insurance against floods.

  3. Flood trends along the Rhine: the role of river training

    Directory of Open Access Journals (Sweden)

    S. Vorogushyn

    2013-10-01

    Full Text Available Several previous studies have detected positive trends in flood flows in German rivers, among others, at Rhine gauges over the past six decades. The presence and detectability of the climate change signal in flood records has been controversially discussed, particularly against the background of massive river training measures in the Rhine. In the past the Rhine catchment has been heavily trained, including the construction of the Rhine weir cascade, flood protection dikes and detention basins. The present study investigates the role of river training on changes in annual maximum daily flows at Rhine gauges starting from Maxau down to Lobith. In particular, the effect of the Rhine weir cascade and of a series of detention basins was investigated. By homogenising the original flood flow records in the period from 1952 till 2009, the annual maximum series were computed that would have been recorded had river training measures not been in place. Using multiple trend analysis, relative changes in the homogenised time series were found to be from a few percentage points to more than 10 percentage points smaller compared to the original records. This effect is attributable to the river training measures, and primarily to the construction of the Rhine weir cascade. The increase in Rhine flood discharges during this period was partly caused by an unfavourable superposition of the Rhine and Neckar flood waves. This superposition resulted from an acceleration of the Rhine waves due to the construction of the weir cascade and associated channelisation and dike heightening. However, at the same time, tributary flows across the entire Upper and Lower Rhine, which enhance annual maximum Rhine peaks, showed strong positive trends. This suggests the dominance of another driver or drivers which acted alongside river training.

  4. Establishment and Practical Application of Flood Warning Stage in Taiwan's River

    Science.gov (United States)

    Yang, Sheng-Hsueh; Chia Yeh, Keh-

    2017-04-01

    In the face of extreme flood events or the possible impact of climate change, non-engineering disaster prevention and early warning work is particularly important. Taiwan is an island topography with more than 3,900 meters of high mountains. The length of the river is less than 100 kilometers. Most of the watershed catchment time is less than 24 hours, which belongs to the river with steep slope and rapid flood. Every year in summer and autumn, several typhoon events invade Taiwan. Typhoons often result in rainfall events in excess of 100 mm/hr or 250 mm/3hr. In the face of Taiwan's terrain and extreme rainfall events, flooding is difficult to avoid. Therefore, most of the river has embankment protection, so that people do not have to face every year flooding caused by economic and life and property losses. However, the river embankment protection is limited. With the increase of the hydrological data, the design criteria for the embankment protection standards in the past was 100 year of flood return period and is now gradually reduced to 25 or 50 year of flood return period. The river authorities are not easy to rise the existing embankment height. The safety of the river embankment in Taiwan is determined by the establishment of the flood warning stage to cope with the possible increase in annual floods and the impact of extreme hydrological events. The flood warning stage is equal to the flood control elevation minus the flood rise rate multiply by the flood early warning time. The control elevation can be the top of the embankment, the design flood level of the river, the embankment gap of the river section, the height of the bridge beam bottom, etc. The flood rise rate is consider the factors such as hydrological stochastic and uncertain rainfall and the effect of flood discharge operation on the flood in the watershed catchment area. The maximum value of the water level difference between the two hours or five hours before the peak value of the analysis

  5. 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

  6. Flood Hazards - A National Threat

    Science.gov (United States)

    ,

    2006-01-01

    In the late summer of 2005, the remarkable flooding brought by Hurricane Katrina, which caused more than $200 billion in losses, constituted the costliest natural disaster in U.S. history. However, even in typical years, flooding causes billions of dollars in damage and threatens lives and property in every State. Natural processes, such as hurricanes, weather systems, and snowmelt, can cause floods. Failure of levees and dams and inadequate drainage in urban areas can also result in flooding. On average, floods kill about 140 people each year and cause $6 billion in property damage. Although loss of life to floods during the past half-century has declined, mostly because of improved warning systems, economic losses have continued to rise due to increased urbanization and coastal development.

  7. Monitoring and Mapping the Hurricane Harvey Flooding in Houston, Texas.

    Science.gov (United States)

    Balaji Bhaskar, M. S.

    2017-12-01

    Monitoring and Mapping the Hurricane Harvey Flooding in Houston, Texas.Urban flooding is a hazard that causes major destruction and loss of life. High intense precipitation events have increased significantly in Houston, Texas in recent years resulting in frequent river and bayou flooding. Many of the historical storm events such as Allison, Rita and Ike have caused several billion dollars in losses for the Houston-Galveston Region. A category 4 Hurricane Harvey made landfall on South Texas resulting in heavy precipitation from Aug 25 to 29 of 2017. About 1 trillion gallons of water fell across Harris County over a 4-day period. This amount of water covers Harris County's 1,800 square miles with an average of 33 inches of water. The long rain event resulted in an average 40inch rainfall across the area in several rain gauges and the maximum rainfall of 49.6 inches was recorded near Clear Creek. The objectives of our study are to 1) Process the Geographic Information System (GIS) and satellite data from the pre and post Hurricane Harvey event in Houston, Texas and 2) Analyze the satellite imagery to map the nature and pattern of the flooding in Houston-Galveston Region. The GIS data of the study area was downloaded and processed from the various publicly available resources such as Houston Galveston Area Council (HGAC), Texas Commission of Environmental Quality (TCEQ) and Texas Natural Resource Information Systems (TNRIS). The satellite data collected soon after the Harvey flooding event were downloaded and processed using the ERDAS image processing software. The flood plain areas surrounding the Brazos River, Buffalo Bayou and the Addicks Barker reservoirs showed severe inundation. The different watershed areas affected by the catastrophic flooding in the wake of Hurricane Harvey were mapped and compared with the pre flooding event.

  8. Fault tree analysis for urban flooding

    NARCIS (Netherlands)

    Ten Veldhuis, J.A.E.; Clemens, F.H.L.R.; Van Gelder, P.H.A.J.M.

    2008-01-01

    Traditional methods to evaluate flood risk mostly focus on storm events as the main cause of flooding. Fault tree analysis is a technique that is able to model all potential causes of flooding and to quantify both the overall probability of flooding and the contributions of all causes of flooding to

  9. Thermosyphon Flooding in Reduced Gravity Environments Test Results

    Science.gov (United States)

    Gibson, Marc A.; Jaworske, Donald A.; Sanzi, Jim; Ljubanovic, Damir

    2013-01-01

    The condenser flooding phenomenon associated with gravity aided two-phase thermosyphons was studied using parabolic flights to obtain the desired reduced gravity environment (RGE). The experiment was designed and built to test a total of twelve titanium water thermosyphons in multiple gravity environments with the goal of developing a model that would accurately explain the correlation between gravitational forces and the maximum axial heat transfer limit associated with condenser flooding. Results from laboratory testing and parabolic flights are included in this report as part I of a two part series. The data analysis and correlations are included in a follow on paper.

  10. Rethinking the relationship between flood risk perception and flood management.

    Science.gov (United States)

    Birkholz, S; Muro, M; Jeffrey, P; Smith, H M

    2014-04-15

    Although flood risk perceptions and their concomitant motivations for behaviour have long been recognised as significant features of community resilience in the face of flooding events, there has, for some time now, been a poorly appreciated fissure in the accompanying literature. Specifically, rationalist and constructivist paradigms in the broader domain of risk perception provide different (though not always conflicting) contexts for interpreting evidence and developing theory. This contribution reviews the major constructs that have been applied to understanding flood risk perceptions and contextualises these within broader conceptual developments around risk perception theory and contemporary thinking around flood risk management. We argue that there is a need to re-examine and re-invigorate flood risk perception research, in a manner that is comprehensively underpinned by more constructivist thinking around flood risk management as well as by developments in broader risk perception research. We draw attention to an historical over-emphasis on the cognitive perceptions of those at risk to the detriment of a richer understanding of a wider range of flood risk perceptions such as those of policy-makers or of tax-payers who live outside flood affected areas as well as the linkages between these perspectives and protective measures such as state-supported flood insurance schemes. Conclusions challenge existing understandings of the relationship between risk perception and flood management, particularly where the latter relates to communication strategies and the extent to which those at risk from flooding feel responsible for taking protective actions. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Flood Risk and Flood hazard maps - Visualisation of hydrological risks

    International Nuclear Information System (INIS)

    Spachinger, Karl; Dorner, Wolfgang; Metzka, Rudolf; Serrhini, Kamal; Fuchs, Sven

    2008-01-01

    Hydrological models are an important basis of flood forecasting and early warning systems. They provide significant data on hydrological risks. In combination with other modelling techniques, such as hydrodynamic models, they can be used to assess the extent and impact of hydrological events. The new European Flood Directive forces all member states to evaluate flood risk on a catchment scale, to compile maps of flood hazard and flood risk for prone areas, and to inform on a local level about these risks. Flood hazard and flood risk maps are important tools to communicate flood risk to different target groups. They provide compiled information to relevant public bodies such as water management authorities, municipalities, or civil protection agencies, but also to the broader public. For almost each section of a river basin, run-off and water levels can be defined based on the likelihood of annual recurrence, using a combination of hydrological and hydrodynamic models, supplemented by an analysis of historical records and mappings. In combination with data related to the vulnerability of a region risk maps can be derived. The project RISKCATCH addressed these issues of hydrological risk and vulnerability assessment focusing on the flood risk management process. Flood hazard maps and flood risk maps were compiled for Austrian and German test sites taking into account existing national and international guidelines. These maps were evaluated by eye-tracking using experimental graphic semiology. Sets of small-scale as well as large-scale risk maps were presented to test persons in order to (1) study reading behaviour as well as understanding and (2) deduce the most attractive components that are essential for target-oriented risk communication. A cognitive survey asking for negative and positive aspects and complexity of each single map complemented the experimental graphic semiology. The results indicate how risk maps can be improved to fit the needs of different user

  12. The Complex Relationship Between Heavy Storms and Floods: Implication on Stormwater Drainage design and Management

    Science.gov (United States)

    Demissie, Y.; Mortuza, M. R.; Moges, E.; Yan, E.; Li, H. Y.

    2017-12-01

    Due to the lack of historical and future streamflow data for flood frequency analysis at or near most drainage sites, it is a common practice to directly estimate the design flood (maximum discharge or volume of stream for a given return period) based on storm frequency analysis and the resulted Intensity-Duration-Frequency (IDF) curves. Such analysis assumes a direct relationship between storms and floods with, for example, the 10-year rainfall expected to produce the 10-year flood. However, in reality, a storm is just one factor among the many other hydrological and metrological factors that can affect the peak flow and hydrograph. Consequently, a heavy storm does not necessarily always lead to flooding or a flood events with the same frequency. This is evident by the observed difference in the seasonality of heavy storms and floods in most regions. In order to understand site specific causal-effect relationship between heavy storms and floods and improve the flood analysis for stormwater drainage design and management, we have examined the contributions of various factors that affect floods using statistical and information theory methods. Based on the identified dominant causal-effect relationships, hydrologic and probability analyses were conducted to develop the runoff IDF curves taking into consideration the snowmelt and rain-on-snow effect, the difference in the storm and flood seasonality, soil moisture conditions, and catchment potential for flash and riverine flooding. The approach was demonstrated using data from military installations located in different parts of the United States. The accuracy of the flood frequency analysis and the resulted runoff IDF curves were evaluated based on the runoff IDF curves developed from streamflow measurements.

  13. 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

  14. 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

  15. Temporal clustering of floods in Germany: Do flood-rich and flood-poor periods exist?

    Science.gov (United States)

    Merz, Bruno; Nguyen, Viet Dung; Vorogushyn, Sergiy

    2016-10-01

    The repeated occurrence of exceptional floods within a few years, such as the Rhine floods in 1993 and 1995 and the Elbe and Danube floods in 2002 and 2013, suggests that floods in Central Europe may be organized in flood-rich and flood-poor periods. This hypothesis is studied by testing the significance of temporal clustering in flood occurrence (peak-over-threshold) time series for 68 catchments across Germany for the period 1932-2005. To assess the robustness of the results, different methods are used: Firstly, the index of dispersion, which quantifies the departure from a homogeneous Poisson process, is investigated. Further, the time-variation of the flood occurrence rate is derived by non-parametric kernel implementation and the significance of clustering is evaluated via parametric and non-parametric tests. Although the methods give consistent overall results, the specific results differ considerably. Hence, we recommend applying different methods when investigating flood clustering. For flood estimation and risk management, it is of relevance to understand whether clustering changes with flood severity and time scale. To this end, clustering is assessed for different thresholds and time scales. It is found that the majority of catchments show temporal clustering at the 5% significance level for low thresholds and time scales of one to a few years. However, clustering decreases substantially with increasing threshold and time scale. We hypothesize that flood clustering in Germany is mainly caused by catchment memory effects along with intra- to inter-annual climate variability, and that decadal climate variability plays a minor role.

  16. 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%.

  17. Maximum Entropy in Drug Discovery

    Directory of Open Access Journals (Sweden)

    Chih-Yuan Tseng

    2014-07-01

    Full Text Available Drug discovery applies multidisciplinary approaches either experimentally, computationally or both ways to identify lead compounds to treat various diseases. While conventional approaches have yielded many US Food and Drug Administration (FDA-approved drugs, researchers continue investigating and designing better approaches to increase the success rate in the discovery process. In this article, we provide an overview of the current strategies and point out where and how the method of maximum entropy has been introduced in this area. The maximum entropy principle has its root in thermodynamics, yet since Jaynes’ pioneering work in the 1950s, the maximum entropy principle has not only been used as a physics law, but also as a reasoning tool that allows us to process information in hand with the least bias. Its applicability in various disciplines has been abundantly demonstrated. We give several examples of applications of maximum entropy in different stages of drug discovery. Finally, we discuss a promising new direction in drug discovery that is likely to hinge on the ways of utilizing maximum entropy.

  18. Flood-inundation maps for the West Branch Delaware River, Delhi, New York, 2012

    Science.gov (United States)

    Coon, William F.; Breaker, Brian K.

    2012-01-01

    Digital flood-inundation maps for a 5-mile reach of the West Branch Delaware River through the Village and part of the Town of Delhi, New York, were created by the U.S. Geological Survey (USGS) in cooperation with the Village of Delhi, the Delaware County Soil and Water Conservation District, and the Delaware County Planning Department. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/ and the Federal Flood Inundation Mapper Web site at http://wim.usgs.gov/FIMI/FloodInundationMapper.html, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) referenced to the USGS streamgage at West Branch Delaware River upstream from Delhi, N.Y. (station number 01421900). In this study, flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model that had been used to produce the flood insurance rate maps for the most recent flood insurance study for the Town and Village of Delhi. This hydraulic model was used to compute 10 water-surface profiles for flood stages at 1-foot (ft) intervals referenced to the streamgage datum and ranging from 7 ft or near bankfull to 16 ft, which exceeds the stages that correspond to both the estimated 0.2-percent annual-exceedance-probability flood (500-year recurrence interval flood) and the maximum recorded peak flow. The simulated water-surface profiles were then combined with a geographic information system (GIS) digital elevation model, which was derived from Light Detection and Ranging (LiDAR) data with a 1.2-ft (0.61-ft root mean squared error) vertical accuracy and 3.3-ft (1-meter) horizontal resolution, to delineate the area flooded at each water level. A map that was produced using this method to delineate the inundated area for the flood that occurred on August 28, 2011, agreed well with highwater marks that had been located in the field using a

  19. 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...

  20. 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...

  1. The Aqueduct Global Flood Analyzer

    Science.gov (United States)

    Iceland, Charles

    2015-04-01

    As population growth and economic growth take place, and as climate change accelerates, many regions across the globe are finding themselves increasingly vulnerable to flooding. A recent OECD study of the exposure of the world's large port cities to coastal flooding found that 40 million people were exposed to a 1 in 100 year coastal flood event in 2005, and the total value of exposed assets was about US 3,000 billion, or 5% of global GDP. By the 2070s, those numbers were estimated to increase to 150 million people and US 35,000 billion, or roughly 9% of projected global GDP. Impoverished people in developing countries are particularly at risk because they often live in flood-prone areas and lack the resources to respond. WRI and its Dutch partners - Deltares, IVM-VU University Amsterdam, Utrecht University, and PBL Netherlands Environmental Assessment Agency - are in the initial stages of developing a robust set of river flood and coastal storm surge risk measures that show the extent of flooding under a variety of scenarios (both current and future), together with the projected human and economic impacts of these flood scenarios. These flood risk data and information will be accessible via an online, easy-to-use Aqueduct Global Flood Analyzer. We will also investigate the viability, benefits, and costs of a wide array of flood risk reduction measures that could be implemented in a variety of geographic and socio-economic settings. Together, the activities we propose have the potential for saving hundreds of thousands of lives and strengthening the resiliency and security of many millions more, especially those who are most vulnerable. Mr. Iceland will present Version 1.0 of the Aqueduct Global Flood Analyzer and provide a preview of additional elements of the Analyzer to be released in the coming years.

  2. Flood Risk, Flood Mitigation, and Location Choice: Evaluating the National Flood Insurance Program's Community Rating System.

    Science.gov (United States)

    Fan, Qin; Davlasheridze, Meri

    2016-06-01

    Climate change is expected to worsen the negative effects of natural disasters like floods. The negative impacts, however, can be mitigated by individuals' adjustments through migration and relocation behaviors. Previous literature has identified flood risk as one significant driver in relocation decisions, but no prior study examines the effect of the National Flood Insurance Program's voluntary program-the Community Rating System (CRS)-on residential location choice. This article fills this gap and tests the hypothesis that flood risk and the CRS-creditable flood control activities affect residential location choices. We employ a two-stage sorting model to empirically estimate the effects. In the first stage, individuals' risk perception and preference heterogeneity for the CRS activities are considered, while mean effects of flood risk and the CRS activities are estimated in the second stage. We then estimate heterogeneous marginal willingness to pay (WTP) for the CRS activities by category. Results show that age, ethnicity and race, educational attainment, and prior exposure to risk explain risk perception. We find significant values for the CRS-creditable mitigation activities, which provides empirical evidence for the benefits associated with the program. The marginal WTP for an additional credit point earned for public information activities, including hazard disclosure, is found to be the highest. Results also suggest that water amenities dominate flood risk. Thus, high amenity values may increase exposure to flood risk, and flood mitigation projects should be strategized in coastal regions accordingly. © 2015 Society for Risk Analysis.

  3. Continuous hydrologic simulation and flood-frequency, hydraulic, and flood-hazard analysis of the Blackberry Creek watershed, Kane County, Illinois

    Science.gov (United States)

    Soong, David T.; Straub, Timothy D.; Murphy, Elizabeth A.

    2006-01-01

    Results of hydrologic model, flood-frequency, hydraulic model, and flood-hazard analysis of the Blackberry Creek watershed in Kane County, Illinois, indicate that the 100-year and 500-year flood plains range from approximately 25 acres in the tributary F watershed (a headwater subbasin at the northeastern corner of the watershed) to almost 1,800 acres in Blackberry Creek main stem. Based on 1996 land-cover data, most of the land in the 100-year and 500-year flood plains was cropland, forested and wooded land, and grassland. A relatively small percentage of urban land was in the flood plains. The Blackberry Creek watershed has undergone rapid urbanization in recent decades. The population and urbanized lands in the watershed are projected to double from the 1990 condition by 2020. Recently, flood-induced damage has occurred more frequently in urbanized areas of the watershed. There are concerns about the effect of urbanization on flood peaks and volumes, future flood-mitigation plans, and potential effects on the water quality and stream habitats. This report describes the procedures used in developing the hydrologic models, estimating the flood-peak discharge magnitudes and recurrence intervals for flood-hazard analysis, developing the hydraulic model, and the results of the analysis in graphical and tabular form. The hydrologic model, Hydrological Simulation Program-FORTRAN (HSPF), was used to perform the simulation of continuous water movements through various patterns of land uses in the watershed. Flood-frequency analysis was applied to an annual maximum series to determine flood quantiles in subbasins for flood-hazard analysis. The Hydrologic Engineering Center-River Analysis System (HEC-RAS) hydraulic model was used to determine the 100-year and 500-year flood elevations, and to determine the 100-year floodway. The hydraulic model was calibrated and verified using high water marks and observed inundation maps for the July 17-18, 1996, flood event. Digital

  4. Floods in the Saguenay

    International Nuclear Information System (INIS)

    Martel, R.; Michaud, E.; Tousignant, P.M.

    1997-01-01

    Footage of a natural disaster that occurred between July 20 and 25 1996, in the Saguenay region of Quebec was documented. A heavy downpour of rain raised the water level of the Kenogami Lake reservoir beyond its capacity. This created huge pressure on its dam that upset the fragile balance between nature and rock. The dam raptured, resulting in a flood of previously unseen proportions. The Riviere au Sable in Jonquiere became an overwhelming body of water. The video showed how the shores of the river were eroded and how apartment buildings were engulfed by the torrent of water. A newly constructed electricity power plant had to be decommissioned, roads were washed away and entire neighborhoods were devastated. The devastation suffered by the cities of Chicoutimi, Jonquiere, Ville de la Baie, Ferland-Boileau, and L'Anse St-Jean was recorded. Thousands of victims of the disaster were evacuated with the help of the Canadian Armed Forces. Some of the work of reconstruction, begun even before the total retreat of the flood, involved restoration of roads, bridges and communication networks, was also shown

  5. Flood risk management in Italy

    DEFF Research Database (Denmark)

    Mysiak, J.; Testella, F.; Bonaiuto, M.

    2013-01-01

    Italy's recent history is punctuated with devastating flood disasters claiming high death toll and causing vast but underestimated economic, social and environmental damage. The responses to major flood and landslide disasters such as the Polesine (1951), Vajont (1963), Firenze (1966), Valtelina...

  6. Peak discharge of a Pleistocene lava-dam outburst flood in Grand Canyon, Arizona, USA

    Science.gov (United States)

    Fenton, Cassandra R.; Webb, Robert H.; Cerling, Thure E.

    2006-03-01

    The failure of a lava dam 165,000 yr ago produced the largest known flood on the Colorado River in Grand Canyon. The Hyaloclastite Dam was up to 366 m high, and geochemical evidence linked this structure to outburst-flood deposits that occurred for 32 km downstream. Using the Hyaloclastite outburst-flood deposits as paleostage indicators, we used dam-failure and unsteady flow modeling to estimate a peak discharge and flow hydrograph. Failure of the Hyaloclastite Dam released a maximum 11 × 10 9 m 3 of water in 31 h. Peak discharges, estimated from uncertainty in channel geometry, dam height, and hydraulic characteristics, ranged from 2.3 to 5.3 × 10 5 m 3 s -1 for the Hyaloclastite outburst flood. This discharge is an order of magnitude greater than the largest known discharge on the Colorado River (1.4 × 10 4 m 3 s -1) and the largest peak discharge resulting from failure of a constructed dam in the USA (6.5 × 10 4 m 3 s -1). Moreover, the Hyaloclastite outburst flood is the oldest documented Quaternary flood and one of the largest to have occurred in the continental USA. The peak discharge for this flood ranks in the top 30 floods (>10 5 m 3 s -1) known worldwide and in the top ten largest floods in North America.

  7. Internal flooding analyses results of Slovak NPPs

    International Nuclear Information System (INIS)

    Sopira, Vladimir

    2000-01-01

    The assessment of the flood risk was the objective of the internal flooding analysis for NPPs Bohunice V1, V2 and Mochovce. All important flooding sources were identified. The rooms containing safety important components were analyzed from the point of view of: Integrity of flood boundaries; Capability for drainage; Flood signalisation; Flood localization and liquidation; Vulnerability of safety system component. The redundancies of safety systems are located mostly separately and no flood can endanger more than single train. It can be concluded that NPPs with WWER-440 are very safe against the flooding initiating event

  8. Maximum stellar iron core mass

    Indian Academy of Sciences (India)

    60, No. 3. — journal of. March 2003 physics pp. 415–422. Maximum stellar iron core mass. F W GIACOBBE. Chicago Research Center/American Air Liquide ... iron core compression due to the weight of non-ferrous matter overlying the iron cores within large .... thermal equilibrium velocities will tend to be non-relativistic.

  9. Maximum entropy beam diagnostic tomography

    International Nuclear Information System (INIS)

    Mottershead, C.T.

    1985-01-01

    This paper reviews the formalism of maximum entropy beam diagnostic tomography as applied to the Fusion Materials Irradiation Test (FMIT) prototype accelerator. The same formalism has also been used with streak camera data to produce an ultrahigh speed movie of the beam profile of the Experimental Test Accelerator (ETA) at Livermore. 11 refs., 4 figs

  10. Maximum entropy beam diagnostic tomography

    International Nuclear Information System (INIS)

    Mottershead, C.T.

    1985-01-01

    This paper reviews the formalism of maximum entropy beam diagnostic tomography as applied to the Fusion Materials Irradiation Test (FMIT) prototype accelerator. The same formalism has also been used with streak camera data to produce an ultrahigh speed movie of the beam profile of the Experimental Test Accelerator (ETA) at Livermore

  11. A portable storage maximum thermometer

    International Nuclear Information System (INIS)

    Fayart, Gerard.

    1976-01-01

    A clinical thermometer storing the voltage corresponding to the maximum temperature in an analog memory is described. End of the measurement is shown by a lamp switch out. The measurement time is shortened by means of a low thermal inertia platinum probe. This portable thermometer is fitted with cell test and calibration system [fr

  12. Neutron spectra unfolding with maximum entropy and maximum likelihood

    International Nuclear Information System (INIS)

    Itoh, Shikoh; Tsunoda, Toshiharu

    1989-01-01

    A new unfolding theory has been established on the basis of the maximum entropy principle and the maximum likelihood method. This theory correctly embodies the Poisson statistics of neutron detection, and always brings a positive solution over the whole energy range. Moreover, the theory unifies both problems of overdetermined and of underdetermined. For the latter, the ambiguity in assigning a prior probability, i.e. the initial guess in the Bayesian sense, has become extinct by virtue of the principle. An approximate expression of the covariance matrix for the resultant spectra is also presented. An efficient algorithm to solve the nonlinear system, which appears in the present study, has been established. Results of computer simulation showed the effectiveness of the present theory. (author)

  13. Developing a Malaysia flood model

    Science.gov (United States)

    Haseldine, Lucy; Baxter, Stephen; Wheeler, Phil; Thomson, Tina

    2014-05-01

    Faced with growing exposures in Malaysia, insurers have a need for models to help them assess their exposure to flood losses. The need for an improved management of flood risks has been further highlighted by the 2011 floods in Thailand and recent events in Malaysia. The increasing demand for loss accumulation tools in Malaysia has lead to the development of the first nationwide probabilistic Malaysia flood model, which we present here. The model is multi-peril, including river flooding for thousands of kilometres of river and rainfall-driven surface water flooding in major cities, which may cause losses equivalent to river flood in some high-density urban areas. The underlying hazard maps are based on a 30m digital surface model (DSM) and 1D/2D hydraulic modelling in JFlow and RFlow. Key mitigation schemes such as the SMART tunnel and drainage capacities are also considered in the model. The probabilistic element of the model is driven by a stochastic event set based on rainfall data, hence enabling per-event and annual figures to be calculated for a specific insurance portfolio and a range of return periods. Losses are estimated via depth-damage vulnerability functions which link the insured damage to water depths for different property types in Malaysia. The model provides a unique insight into Malaysian flood risk profiles and provides insurers with return period estimates of flood damage and loss to property portfolios through loss exceedance curve outputs. It has been successfully validated against historic flood events in Malaysia and is now being successfully used by insurance companies in the Malaysian market to obtain reinsurance cover.

  14. Floods of December 1966 in southwestern Utah

    Science.gov (United States)

    Butler, Elmer; Mundorff, J.C.

    1970-01-01

    Severe floods occurred in parts of southwestern Utah on December 5-6, 1966, as a result of precipitation of about 1 inch to more than 12 inches during December 3-6. The flood on the Virgin River was the greatest since the first settlers arrived in 1860.The peak discharge of the Virgin River at Virgin, Utah, was 22,830 cubic feet per second on December 6; this exceeded the previous maximum discharge of 13,500 cubic feet per second on March 3, 1938, and September 17, 1961, and probably has a recurrence interval of 100 years. At eight other gage sites in the flood area, the peak discharge in December 1966 was the highest of record; the recurrence intervals of some of the peak discharges may be 100 years. The flood peaks were generally of short duration and most streams receded to near base flow within 24 hours.The dissolved-solids content was significantly lower in the Virgin River at Virgin than at St. George, about 25 miles downstream; the water was of the calcium sulfate type at both sites. Data for the Santa Clara River above Winsor Dam and the Santa Clara River near Santa Clara show a significant increase in dissolved solids between the two sites. The water above Winsor Dam was of the calcium bicarbonate type, and the water near Santa Clara was of the calcium bicarbonate sulfate type.The suspended-sediment discharge, during the period December 5-8, 1966, at Santa Clara River above Winsor Dam, near Santa Clara was about foyer times greater than all the suspended-sediment discharge during the preceding 3 years ; the suspended-sediment discharge of the Virgin River at Virgin was greater during the 4-day period than during any one of the preceding 3 years.Nearly all the flood damage in the area occurred in the Virgin River basin. According to the Soil Conservation Service, total damage in the Dixie Soil Conservation District in Washington County was about $835,000; 60 percent of the damage was caused by floodwater and 40 percent by deposited sediment.

  15. Improving Gas Flooding Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Reid Grigg; Robert Svec; Zheng Zeng; Alexander Mikhalin; Yi Lin; Guoqiang Yin; Solomon Ampir; Rashid Kassim

    2008-03-31

    This study focuses on laboratory studies with related analytical and numerical models, as well as work with operators for field tests to enhance our understanding of and capabilities for more efficient enhanced oil recovery (EOR). Much of the work has been performed at reservoir conditions. This includes a bubble chamber and several core flood apparatus developed or modified to measure interfacial tension (IFT), critical micelle concentration (CMC), foam durability, surfactant sorption at reservoir conditions, and pressure and temperature effects on foam systems.Carbon dioxide and N{sub 2} systems have been considered, under both miscible and immiscible conditions. The injection of CO2 into brine-saturated sandstone and carbonate core results in brine saturation reduction in the range of 62 to 82% brine in the tests presented in this paper. In each test, over 90% of the reduction occurred with less than 0.5 PV of CO{sub 2} injected, with very little additional brine production after 0.5 PV of CO{sub 2} injected. Adsorption of all considered surfactant is a significant problem. Most of the effect is reversible, but the amount required for foaming is large in terms of volume and cost for all considered surfactants. Some foams increase resistance to the value beyond what is practical in the reservoir. Sandstone, limestone, and dolomite core samples were tested. Dissolution of reservoir rock and/or cement, especially carbonates, under acid conditions of CO2 injection is a potential problem in CO2 injection into geological formations. Another potential change in reservoir injectivity and productivity will be the precipitation of dissolved carbonates as the brine flows and pressure decreases. The results of this report provide methods for determining surfactant sorption and can be used to aid in the determination of surfactant requirements for reservoir use in a CO{sub 2}-foam flood for mobility control. It also provides data to be used to determine rock permeability

  16. Regional early flood warning system: design and implementation

    Science.gov (United States)

    Chang, L. C.; Yang, S. N.; Kuo, C. L.; Wang, Y. F.

    2017-12-01

    This study proposes a prototype of the regional early flood inundation warning system in Tainan City, Taiwan. The AI technology is used to forecast multi-step-ahead regional flood inundation maps during storm events. The computing time is only few seconds that leads to real-time regional flood inundation forecasting. A database is built to organize data and information for building real-time forecasting models, maintaining the relations of forecasted points, and displaying forecasted results, while real-time data acquisition is another key task where the model requires immediately accessing rain gauge information to provide forecast services. All programs related database are constructed in Microsoft SQL Server by using Visual C# to extracting real-time hydrological data, managing data, storing the forecasted data and providing the information to the visual map-based display. The regional early flood inundation warning system use the up-to-date Web technologies driven by the database and real-time data acquisition to display the on-line forecasting flood inundation depths in the study area. The friendly interface includes on-line sequentially showing inundation area by Google Map, maximum inundation depth and its location, and providing KMZ file download of the results which can be watched on Google Earth. The developed system can provide all the relevant information and on-line forecast results that helps city authorities to make decisions during typhoon events and make actions to mitigate the losses.

  17. Flood Inundation Mapping and Emergency Operations during Hurricane Harvey

    Science.gov (United States)

    Fang, N. Z.; Cotter, J.; Gao, S.; Bedient, P. B.; Yung, A.; Penland, C.

    2017-12-01

    Hurricane Harvey struck the Gulf Coast as Category 4 on August 25, 2017 with devastating and life-threatening floods in Texas. Harris County received up to 49 inches of rainfall over a 5-day period and experienced flooding level and impacts beyond any previous storm in Houston's history. The depth-duration-frequency analysis reveals that the areal average rainfall for Brays Bayou surpasses the 500-year rainfall in both 24 and 48 hours. To cope with this unprecedented event, the researchers at the University of Texas at Arlington and Rice University worked closely with the U.S. Army Corps of Engineers (USACE), the National Weather Service (NWS), the Texas Division of Emergency Management (TDEM), Walter P. Moore and Associates, Inc. and Halff Associates, to conduct a series of meteorological, hydrologic and hydraulic analyses to delineate flood inundation maps. Up to eight major watersheds in Harris County were delineated based the available QPE data from WGRFC. The inundation map over Brays Bayou with their impacts from Hurricane Harvey was delineated in comparison with those of 100-, 500-year, and Probable Maximum Precipitation (PMP) design storms. This presentation will provide insights for both engineers and planners to re-evaluate the existing flood infrastructure and policy, which will help build Houston stronger for future extreme storms. The collaborative effort among the federal, academic, and private entities clearly demonstrates an effective approach for flood inundation mapping initiatives for the nation.

  18. STATIONARITY OF ANNUAL MAXIMUM DAILY STREAMFLOW TIME SERIES IN SOUTH-EAST BRAZILIAN RIVERS

    Directory of Open Access Journals (Sweden)

    Jorge Machado Damázio

    2015-08-01

    Full Text Available DOI: 10.12957/cadest.2014.18302The paper presents a statistical analysis of annual maxima daily streamflow between 1931 and 2013 in South-East Brazil focused in detecting and modelling non-stationarity aspects. Flood protection for the large valleys in South-East Brazil is provided by multiple purpose reservoir systems built during 20th century, which design and operation plans has been done assuming stationarity of historical flood time series. Land cover changes and rapidly-increasing level of atmosphere greenhouse gases of the last century may be affecting flood regimes in these valleys so that it can be that nonstationary modelling should be applied to re-asses dam safety and flood control operation rules at the existent reservoir system. Six annual maximum daily streamflow time series are analysed. The time series were plotted together with fitted smooth loess functions and non-parametric statistical tests are performed to check the significance of apparent trends shown by the plots. Non-stationarity is modelled by fitting univariate extreme value distribution functions which location varies linearly with time. Stationarity and non-stationarity modelling are compared with the likelihood ratio statistic. In four of the six analyzed time series non-stationarity modelling outperformed stationarity modelling.Keywords: Stationarity; Extreme Value Distributions; Flood Frequency Analysis; Maximum Likelihood Method.

  19. Climate, orography and scale controls on flood frequency in Triveneto (Italy

    Directory of Open Access Journals (Sweden)

    S. Persiano

    2016-05-01

    Full Text Available The growing concern about the possible effects of climate change on flood frequency regime is leading Authorities to review previously proposed reference procedures for design-flood estimation, such as national flood frequency models. Our study focuses on Triveneto, a broad geographical region in North-eastern Italy. A reference procedure for design flood estimation in Triveneto is available from the Italian NCR research project "VA.PI.", which considered Triveneto as a single homogeneous region and developed a regional model using annual maximum series (AMS of peak discharges that were collected up to the 1980s by the former Italian Hydrometeorological Service. We consider a very detailed AMS database that we recently compiled for 76 catchments located in Triveneto. All 76 study catchments are characterized in terms of several geomorphologic and climatic descriptors. The objective of our study is threefold: (1 to inspect climatic and scale controls on flood frequency regime; (2 to verify the possible presence of changes in flood frequency regime by looking at changes in time of regional L-moments of annual maximum floods; (3 to develop an updated reference procedure for design flood estimation in Triveneto by using a focused-pooling approach (i.e. Region of Influence, RoI. Our study leads to the following conclusions: (1 climatic and scale controls on flood frequency regime in Triveneto are similar to the controls that were recently found in Europe; (2 a single year characterized by extreme floods can have a remarkable influence on regional flood frequency models and analyses for detecting possible changes in flood frequency regime; (3 no significant change was detected in the flood frequency regime, yet an update of the existing reference procedure for design flood estimation is highly recommended and we propose the RoI approach for properly representing climate and scale controls on flood frequency in Triveneto, which cannot be regarded

  20. The Influence of Flooding Risk on Infrastructure Development in Western Sydney

    Directory of Open Access Journals (Sweden)

    Alan Jeary

    2012-11-01

    Full Text Available Data relating to flood events in the west Sydney area of Windsor, have been re-analysed using extreme value statistics, and the analysis has shown that the risk of occurrence of the probable maximum flood is greater than previously assumed using conventional statistical methods.The response of the New South Wales Government to the perceived risk is discussed and the efficacy of their strategy of relying on passing information to local residents has been tested by the use of a survey of residents of the area.The survey of Windsor residents showed that a significant percentage of the population had no knowledge of the flood risk. Of the rest of the population there was little or no knowledge of the effects that a severe flood might have, and there was little appreciation of the yearly risk of floods that would affect the town. Overall, it was concluded that the main mitigation strategy of government has been ineffective.

  1. Flooding studies of proposed repository locations in the Palo Duro Basin of the Texas Panhandle

    International Nuclear Information System (INIS)

    1985-04-01

    This report contains the results of flooding studies of those stream channels that drain the proposed locations of a high-level nuclear-waste repository in Deaf Smith and Swisher Counties, Texas. Included are computations of the flood hydrographs and water surface profiles of the 100-year, 500-year, and probable maximum floods for Palo Duro Creek, Tule Creek, and Pleasant Draw. The hydrographs were produced according to the method of the Soil Conservation Service for ungaged watersheds, and the computations were made with computer programs developed by the US Army Corps of Engineers. The flood hydrographs were computed with the HEC-1 Flood Hydrograph Package and the water surface elevations with the HEC-2 Water Surface Profiles program. 76 refs., 19 figs., 16 tabs

  2. On Maximum Entropy and Inference

    Directory of Open Access Journals (Sweden)

    Luigi Gresele

    2017-11-01

    Full Text Available Maximum entropy is a powerful concept that entails a sharp separation between relevant and irrelevant variables. It is typically invoked in inference, once an assumption is made on what the relevant variables are, in order to estimate a model from data, that affords predictions on all other (dependent variables. Conversely, maximum entropy can be invoked to retrieve the relevant variables (sufficient statistics directly from the data, once a model is identified by Bayesian model selection. We explore this approach in the case of spin models with interactions of arbitrary order, and we discuss how relevant interactions can be inferred. In this perspective, the dimensionality of the inference problem is not set by the number of parameters in the model, but by the frequency distribution of the data. We illustrate the method showing its ability to recover the correct model in a few prototype cases and discuss its application on a real dataset.

  3. Maximum Water Hammer Sensitivity Analysis

    OpenAIRE

    Jalil Emadi; Abbas Solemani

    2011-01-01

    Pressure waves and Water Hammer occur in a pumping system when valves are closed or opened suddenly or in the case of sudden failure of pumps. Determination of maximum water hammer is considered one of the most important technical and economical items of which engineers and designers of pumping stations and conveyance pipelines should take care. Hammer Software is a recent application used to simulate water hammer. The present study focuses on determining significance of ...

  4. Maximum Gene-Support Tree

    Directory of Open Access Journals (Sweden)

    Yunfeng Shan

    2008-01-01

    Full Text Available Genomes and genes diversify during evolution; however, it is unclear to what extent genes still retain the relationship among species. Model species for molecular phylogenetic studies include yeasts and viruses whose genomes were sequenced as well as plants that have the fossil-supported true phylogenetic trees available. In this study, we generated single gene trees of seven yeast species as well as single gene trees of nine baculovirus species using all the orthologous genes among the species compared. Homologous genes among seven known plants were used for validation of the finding. Four algorithms—maximum parsimony (MP, minimum evolution (ME, maximum likelihood (ML, and neighbor-joining (NJ—were used. Trees were reconstructed before and after weighting the DNA and protein sequence lengths among genes. Rarely a gene can always generate the “true tree” by all the four algorithms. However, the most frequent gene tree, termed “maximum gene-support tree” (MGS tree, or WMGS tree for the weighted one, in yeasts, baculoviruses, or plants was consistently found to be the “true tree” among the species. The results provide insights into the overall degree of divergence of orthologous genes of the genomes analyzed and suggest the following: 1 The true tree relationship among the species studied is still maintained by the largest group of orthologous genes; 2 There are usually more orthologous genes with higher similarities between genetically closer species than between genetically more distant ones; and 3 The maximum gene-support tree reflects the phylogenetic relationship among species in comparison.

  5. LCLS Maximum Credible Beam Power

    International Nuclear Information System (INIS)

    Clendenin, J.

    2005-01-01

    The maximum credible beam power is defined as the highest credible average beam power that the accelerator can deliver to the point in question, given the laws of physics, the beam line design, and assuming all protection devices have failed. For a new accelerator project, the official maximum credible beam power is determined by project staff in consultation with the Radiation Physics Department, after examining the arguments and evidence presented by the appropriate accelerator physicist(s) and beam line engineers. The definitive parameter becomes part of the project's safety envelope. This technical note will first review the studies that were done for the Gun Test Facility (GTF) at SSRL, where a photoinjector similar to the one proposed for the LCLS is being tested. In Section 3 the maximum charge out of the gun for a single rf pulse is calculated. In Section 4, PARMELA simulations are used to track the beam from the gun to the end of the photoinjector. Finally in Section 5 the beam through the matching section and injected into Linac-1 is discussed

  6. Floods of June-July 1957 in Indiana

    Science.gov (United States)

    Schoppenhorst, Charles E.

    1958-01-01

    The floods of June-July 1957 exceeded those previously known on some of the tributaries of the Wabash and White Rivers in central Indiana. Six lives were lost, 1,282 dwellings were damaged, and 125 business places were flooded. Heavy rains of June 27 and 28 resulted from remnants of Hurricane Audrey meeting a front that lay across central Indiana. Heaviest rainfall reported for the storm period at a U.S. Weather Bureau station was 10.15 inches at Rockville. Previous maximum stages during the period of record were exceeded at 12 gaging stations. The peak stage on Raccoon Creek at Mansfield exceeded the previous maximum known stage, which occurred in 1875. One of the notable rates of discharge recorded was 245 cfs per square mile from a drainage area of 440 square miles on Raccoon Creek at Coxville.

  7. An Evaluation of Selected Extraordinary Floods in the United States Reported by the U.S. Geological Survey and Implications for Future Advancement of Flood Science

    Science.gov (United States)

    Costa, John E.; Jarrett, Robert D.

    2008-01-01

    Thirty flood peak discharges determine the envelope curve of maximum floods documented in the United States by the U.S. Geological Survey. These floods occurred from 1927 to 1978 and are extraordinary not just in their magnitude, but in their hydraulic and geomorphic characteristics. The reliability of the computed discharge of these extraordinary floods was reviewed and evaluated using current (2007) best practices. Of the 30 flood peak discharges investigated, only 7 were measured at daily streamflow-gaging stations that existed when the flood occurred, and 23 were measured at miscellaneous (ungaged) sites. Methods used to measure these 30 extraordinary flood peak discharges consisted of 21 slope-area measurements, 2 direct current-meter measurements, 1 culvert measurement, 1 rating-curve extension, and 1 interpolation and rating-curve extension. The remaining four peak discharges were measured using combinations of culvert, slope-area, flow-over-road, and contracted-opening measurements. The method of peak discharge determination for one flood is unknown. Changes to peak discharge or rating are recommended for 20 of the 30 flood peak discharges that were evaluated. Nine floods retained published peak discharges, but their ratings were downgraded. For two floods, both peak discharge and rating were corrected and revised. Peak discharges for five floods that are subject to significant uncertainty due to complex field and hydraulic conditions, were re-rated as estimates. This study resulted in 5 of the 30 peak discharges having revised values greater than about 10 percent different from the original published values. Peak discharges were smaller for three floods (North Fork Hubbard Creek, Texas; El Rancho Arroyo, New Mexico; South Fork Wailua River, Hawaii), and two peak discharges were revised upward (Lahontan Reservoir tributary, Nevada; Bronco Creek, Arizona). Two peak discharges were indeterminate because they were concluded to have been debris flows with peak

  8. Flooding Fragility Experiments and Prediction

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Curtis L. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Tahhan, Antonio [Idaho National Lab. (INL), Idaho Falls, ID (United States); Muchmore, Cody [Idaho National Lab. (INL), Idaho Falls, ID (United States); Nichols, Larinda [Idaho National Lab. (INL), Idaho Falls, ID (United States); Bhandari, Bishwo [Idaho National Lab. (INL), Idaho Falls, ID (United States); Pope, Chad [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-01

    This report describes the work that has been performed on flooding fragility, both the experimental tests being carried out and the probabilistic fragility predictive models being produced in order to use the text results. Flooding experiments involving full-scale doors have commenced in the Portal Evaluation Tank. The goal of these experiments is to develop a full-scale component flooding experiment protocol and to acquire data that can be used to create Bayesian regression models representing the fragility of these components. This work is in support of the Risk-Informed Safety Margin Characterization (RISMC) Pathway external hazards evaluation research and development.

  9. Modelling maximum river flow by using Bayesian Markov Chain Monte Carlo

    Science.gov (United States)

    Cheong, R. Y.; Gabda, D.

    2017-09-01

    Analysis of flood trends is vital since flooding threatens human living in terms of financial, environment and security. The data of annual maximum river flows in Sabah were fitted into generalized extreme value (GEV) distribution. Maximum likelihood estimator (MLE) raised naturally when working with GEV distribution. However, previous researches showed that MLE provide unstable results especially in small sample size. In this study, we used different Bayesian Markov Chain Monte Carlo (MCMC) based on Metropolis-Hastings algorithm to estimate GEV parameters. Bayesian MCMC method is a statistical inference which studies the parameter estimation by using posterior distribution based on Bayes’ theorem. Metropolis-Hastings algorithm is used to overcome the high dimensional state space faced in Monte Carlo method. This approach also considers more uncertainty in parameter estimation which then presents a better prediction on maximum river flow in Sabah.

  10. Linking flood peak, flood volume and inundation extent: a DEM-based approach

    Science.gov (United States)

    Rebolho, Cédric; Furusho-Percot, Carina; Blaquière, Simon; Brettschneider, Marco; Andréassian, Vazken

    2017-04-01

    Traditionally, flood inundation maps are computed based on the Shallow Water Equations (SWE) in one or two dimensions, with various simplifications that have proved to give good results. However, the complexity of the SWEs often requires a numerical resolution which can need long computing time, as well as detailed cross section data: this often results in restricting these models to rather small areas abundant with high quality data. This, along with the necessity for fast inundation mapping, are the reason why rapid inundation models are being designed, working for (almost) any river with a minimum amount of data and, above all, easily available data. Our model tries to follow this path by using a 100m DEM over France from which are extracted a drainage network and the associated drainage areas. It is based on two pre-existing methods: (1) SHYREG (Arnaud et al.,2013), a regionalized approach used to calculate the 2-year and 10-year flood quantiles (used as approximated bankfull flow and maximum discharge, respectively) for each river pixel of the DEM (below a 10 000 km2 drainage area) and (2) SOCOSE (Mailhol,1980), which gives, amongst other things, an empirical formula of a characteristic flood duration (for each pixel) based on catchment area, average precipitation and temperature. An overflow volume for each river pixel is extracted from a triangular shaped synthetic hydrograph designed with SHYREG quantiles and SOCOSE flood duration. The volume is then spread from downstream to upstream one river pixel at a time. When the entire hydrographic network is processed, the model stops and generates a map of potential inundation area associated with the 10-year flood quantile. Our model can also be calibrated using past-events inundation maps by adjusting two parameters, one which modifies the overflow duration, and the other, equivalent to a minimum drainage area for river pixels to be flooded. Thus, in calibration on a sample of 42 basins, the first draft of the

  11. Structural evaluation of multifunctional flood defenses

    NARCIS (Netherlands)

    Voorendt, M.Z.; Kothuis, Baukje; Kok, Matthijs

    2017-01-01

    Flood risk reduction aims to minimize losses in low-lying areas. One of the ways to reduce flood risks is to protect land by means of flood defenses. The Netherlands has a long tradition of flood protection and, therefore, a wide variety of technical reports written

  12. Local Flood Action Groups: Governance And Resilience

    NARCIS (Netherlands)

    Forrest, Steven; Trell, Elen-Maarja; Woltjer, Johan; Macoun, Milan; Maier, Karel

    2015-01-01

    A diverse range of citizen groups focusing on flood risk management have been identified in several European countries. The paper discusses the role of flood action (citizen) groups in the context of flood resilience and will do this by analysing the UK and its diverse range of flood groups. These

  13. Adjustable Robust Strategies for Flood Protection

    NARCIS (Netherlands)

    Postek, Krzysztof; den Hertog, Dick; Kind, J.; Pustjens, Chris

    2016-01-01

    Flood protection is of major importance to many flood-prone regions and involves substantial investment and maintenance costs. Modern flood risk management requires often to determine a cost-efficient protection strategy, i.e., one with lowest possible long run cost and satisfying flood protection

  14. 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

  15. The probability of flooding wave occurrence and the vulnerability of the Kosovo territory settlements

    Directory of Open Access Journals (Sweden)

    Valjarević Aleksandar

    2013-01-01

    Full Text Available The work displays the presumed laws of flooding waves which would occur if the 1976 situation when the great floods in Kosovo happened reoccurred again. On a 1:300000 multilayer map of Kosovo and Metohia, there are areas which would have been flooded in case of a maximum flooding wave, and what is also shown is the areas which were covered in water as the average was measured, including the areas used as projects of minimal flooding wave value. There is a layer showing the points with regular flood defense, including the places where protection needs to establish. The map includes the ratio of 1:300000, whilst the areas are calculated with the help of processing their dynamic static’s, as well as using the formulae Gumbel Distribution and Weibull Formula. The data have been calculated with their maximum value, including the average and the minimum of flooding period embracing the time of 40 years. [Projekat Ministarstva nauke Republike Srbije, br. III44006 i br. 176019

  16. Estimation of design floods in ungauged catchments using a regional index flood method. A case study of Lake Victoria Basin in Kenya

    Science.gov (United States)

    Nobert, Joel; Mugo, Margaret; Gadain, Hussein

    Reliable estimation of flood magnitudes corresponding to required return periods, vital for structural design purposes, is impacted by lack of hydrological data in the study area of Lake Victoria Basin in Kenya. Use of regional information, derived from data at gauged sites and regionalized for use at any location within a homogenous region, would improve the reliability of the design flood estimation. Therefore, the regional index flood method has been applied. Based on data from 14 gauged sites, a delineation of the basin into two homogenous regions was achieved using elevation variation (90-m DEM), spatial annual rainfall pattern and Principal Component Analysis of seasonal rainfall patterns (from 94 rainfall stations). At site annual maximum series were modelled using the Log normal (LN) (3P), Log Logistic Distribution (LLG), Generalized Extreme Value (GEV) and Log Pearson Type 3 (LP3) distributions. The parameters of the distributions were estimated using the method of probability weighted moments. Goodness of fit tests were applied and the GEV was identified as the most appropriate model for each site. Based on the GEV model, flood quantiles were estimated and regional frequency curves derived from the averaged at site growth curves. Using the least squares regression method, relationships were developed between the index flood, which is defined as the Mean Annual Flood (MAF) and catchment characteristics. The relationships indicated area, mean annual rainfall and altitude were the three significant variables that greatly influence the index flood. Thereafter, estimates of flood magnitudes in ungauged catchments within a homogenous region were estimated from the derived equations for index flood and quantiles from the regional curves. These estimates will improve flood risk estimation and to support water management and engineering decisions and actions.

  17. Flood-inundation maps for the Flatrock River at Columbus, Indiana, 2012

    Science.gov (United States)

    Coon, William F.

    2013-01-01

    Digital flood-inundation maps for a 5-mile reach of the Flatrock River on the western side of Columbus, Indiana, from County Road 400N to the river mouth at the confluence with Driftwood River, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Department of Transportation. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/ and the Federal Flood Inundation Mapper Web site at http://wim.usgs.gov/FIMI/FloodInundationMapper.html, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage on the Flatrock River at Columbus (station number 03363900). Near-real-time stages at this streamgage may be obtained on the Internet from the USGS National Water Information System at http://waterdata.usgs.gov/ or the National Weather Service (NWS) Advanced Hydrologic Prediction Service, which also presents the USGS data, at http:/water.weather.gov/ahps/. Flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The model was calibrated by using the most current stage-discharge relation at the Flatrock River streamgage, high-water marks that were surveyed following the flood of June 7, 2008, and water-surface profiles from the current flood-insurance study for the City of Columbus. The hydraulic model was then used to compute 12 water-surface profiles for flood stages at 1-foot (ft) intervals referenced to the streamgage datum and ranging from 9 ft or near bankfull to 20 ft, which exceeds the stages that correspond to both the estimated 0.2-percent annual exceedance probability flood (500-year recurrence interval flood) and the maximum recorded peak flow. The simulated water-surface profiles were then combined with a Geographic Information System digital elevation model (derived from Light Detection and Ranging (LiDAR) data having a 0.37 ft

  18. Flood triggering in Switzerland: the role of daily to monthly preceding precipitation

    Science.gov (United States)

    Froidevaux, P.; Schwanbeck, J.; Weingartner, R.; Chevalier, C.; Martius, O.

    2015-09-01

    Determining the role of different precipitation periods for peak discharge generation is crucial for both projecting future changes in flood probability and for short- and medium-range flood forecasting. In this study, catchment-averaged daily precipitation time series are analyzed prior to annual peak discharge events (floods) in Switzerland. The high number of floods considered - more than 4000 events from 101 catchments have been analyzed - allows to derive significant information about the role of antecedent precipitation for peak discharge generation. Based on the analysis of precipitation times series, a new separation of flood-related precipitation periods is proposed: (i) the period 0 to 1 day before flood days, when the maximum flood-triggering precipitation rates are generally observed, (ii) the period 2 to 3 days before flood days, when longer-lasting synoptic situations generate "significantly higher than normal" precipitation amounts, and (iii) the period from 4 days to 1 month before flood days when previous wet episodes may have already preconditioned the catchment. The novelty of this study lies in the separation of antecedent precipitation into the precursor antecedent precipitation (4 days before floods or earlier, called PRE-AP) and the short range precipitation (0 to 3 days before floods, a period when precipitation is often driven by one persistent weather situation like e.g., a stationary low-pressure system). A precise separation of "antecedent" and "peak-triggering" precipitation is not attempted. Instead, the strict definition of antecedent precipitation periods permits a direct comparison of all catchments. The precipitation accumulating 0 to 3 days before an event is the most relevant for floods in Switzerland. PRE-AP precipitation has only a weak and region-specific influence on flood probability. Floods were significantly more frequent after wet PRE-AP periods only in the Jura Mountains, in the western and eastern Swiss plateau, and at

  19. Smoky River coal flood risk mapping study

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-06-01

    The Canada-Alberta Flood Damage Reduction Program (FDRP) is designed to reduce flood damage by identifying areas susceptible to flooding and by encouraging application of suitable land use planning, zoning, and flood preparedness and proofing. The purpose of this study is to define flood risk and floodway limits along the Smoky River near the former Smoky River Coal (SRC) plant. Alberta Energy has been responsible for the site since the mine and plant closed in 2000. The study describes flooding history, available data, features of the river and valley, calculation of flood levels, and floodway determination, and includes flood risk maps. The HEC-RAS program is used for the calculations. The flood risk area was calculated using the 1:100 year return period flood as the hydrological event. 7 refs., 11 figs., 7 tabs., 3 apps.

  20. Flood Resilient Systems and their Application for Flood Resilient Planning

    Science.gov (United States)

    Manojlovic, N.; Gabalda, V.; Antanaskovic, D.; Gershovich, I.; Pasche, E.

    2012-04-01

    Following the paradigm shift in flood management from traditional to more integrated approaches, and considering the uncertainties of future development due to drivers such as climate change, one of the main emerging tasks of flood managers becomes the development of (flood) resilient cities. It can be achieved by application of non-structural - flood resilience measures, summarised in the 4As: assistance, alleviation, awareness and avoidance (FIAC, 2007). As a part of this strategy, the key aspect of development of resilient cities - resilient built environment can be reached by efficient application of Flood Resilience Technology (FReT) and its meaningful combination into flood resilient systems (FRS). FRS are given as [an interconnecting network of FReT which facilitates resilience (including both restorative and adaptive capacity) to flooding, addressing physical and social systems and considering different flood typologies] (SMARTeST, http://www.floodresilience.eu/). Applying the system approach (e.g. Zevenbergen, 2008), FRS can be developed at different scales from the building to the city level. Still, a matter of research is a method to define and systematise different FRS crossing those scales. Further, the decision on which resilient system is to be applied for the given conditions and given scale is a complex task, calling for utilisation of decision support tools. This process of decision-making should follow the steps of flood risk assessment (1) and development of a flood resilience plan (2) (Manojlovic et al, 2009). The key problem in (2) is how to match the input parameters that describe physical&social system and flood typology to the appropriate flood resilient system. Additionally, an open issue is how to integrate the advances in FReT and findings on its efficiency into decision support tools. This paper presents a way to define, systematise and make decisions on FRS at different scales of an urban system developed within the 7th FP Project

  1. Flood Modeling Using a Synthesis of Multi-Platform LiDAR Data

    Directory of Open Access Journals (Sweden)

    Ryan M. Csontos

    2013-09-01

    Full Text Available This study examined the utility of a high resolution ground-based (mobile and terrestrial Light Detection and Ranging (LiDAR dataset (0.2 m point-spacing supplemented with a coarser resolution airborne LiDAR dataset (5 m point-spacing for use in a flood inundation analysis. The techniques for combining multi-platform LiDAR data into a composite dataset in the form of a triangulated irregular network (TIN are described, and quantitative comparisons were made to a TIN generated solely from the airborne LiDAR dataset. For example, a maximum land surface elevation difference of 1.677 m and a mean difference of 0.178 m were calculated between the datasets based on sample points. Utilizing the composite and airborne LiDAR-derived TINs, a flood inundation comparison was completed using a one-dimensional steady flow hydraulic modeling analysis. Quantitative comparisons of the water surface profiles and depth grids indicated an underestimation of flooding extent, volume, and maximum flood height using the airborne LiDAR data alone. A 35% increase in maximum flood height was observed using the composite LiDAR dataset. In addition, the extents of the water surface profiles generated from the two datasets were found to be statistically significantly different. The urban and mountainous characteristics of the study area as well as the density (file size of the high resolution ground based LiDAR data presented both opportunities and challenges for flood modeling analyses.

  2. 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.

  3. Generic maximum likely scale selection

    DEFF Research Database (Denmark)

    Pedersen, Kim Steenstrup; Loog, Marco; Markussen, Bo

    2007-01-01

    in this work is on applying this selection principle under a Brownian image model. This image model provides a simple scale invariant prior for natural images and we provide illustrative examples of the behavior of our scale estimation on such images. In these illustrative examples, estimation is based......The fundamental problem of local scale selection is addressed by means of a novel principle, which is based on maximum likelihood estimation. The principle is generally applicable to a broad variety of image models and descriptors, and provides a generic scale estimation methodology. The focus...

  4. 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...

  5. FEMA Flood Insurance Studies Inventory

    Data.gov (United States)

    Kansas Data Access and Support Center — This digital data set provides an inventory of Federal Emergency Management Agency (FEMA) Flood Insurance Studies (FIS) that have been conducted for communities and...

  6. Flooding characteristics of Goodloe packing

    International Nuclear Information System (INIS)

    Begovich, J.M.; Watson, J.S.

    1976-08-01

    Experimental flooding data for the countercurrent flow of air and water in a 7.62-cm-diam glass column filled with Goodloe packing were compared with a correlation reported by the packing manufacturer. Flooding rates observed in this study were as low as one-half those predicted by the correlation. Rearranging the packing by inverting the column and removing some packing segments yielded results similar to the correlation for liquid-to-gas (L/G) mass flow rate ratios greater than 10, but the experimental flooding curve fell significantly below the correlation at lower L/G ratios. When the column was repacked with new packing, the results were essentially the same as those obtained in the inverted column. Thus, it is believed that a carefully packed column is more likely to yield flooding rates similar to those obtained in the new or inverted columns rather than rates predicted by the original correlation

  7. Flood Fighting Products Research Facility

    Data.gov (United States)

    Federal Laboratory Consortium — A wave research basin at the ERDC Coastal and Hydraulics Laboratory has been modified specifically for testing of temporary, barrier-type, flood fighting products....

  8. FLOOD CHARACTERISTICS AND MANAGEMENT ADAPTATIONS ...

    African Journals Online (AJOL)

    Dr Osondu

    2011-10-26

    Oct 26, 2011 ... Ethiopian Journal of Environmental Studies and Management Vol. ... people are estimated to be at such risk by 2080 .... SCS-CN method is based on the water balance .... and psychological burden of flood hazard often fall.

  9. Minor floods of 1938 in the North Atlantic States

    Science.gov (United States)

    ,

    1947-01-01

    Five noteworthy floods occurred during 1938 in the North Atlantic States. The first flood was in January, the others were in June, July, August, and September. The floods of January, June, and August were relatively local events in Connecticut, New Jersey, and New York, respectively. The floods of July and September were widespread, reaching from New Jersey and New York to New Hampshire in generally coincident locations. The flood of September, the most severe, is described in appropriate detail in Water-Supply Paper 867; the others in this volume are in separate sections arranged chronologically. Extraordinary floods in Connecticut during January 1938 resulted from a critical combination of warm rainfall and virtual overnight melting of the accumulated snowfall of winter. Seven small streams in central and western Connecticut rose to levels on January 25 higher than those reached during the great floods of March 1936. Crest discharge of these streams approximated 100 second-feet per square mile. Ice cover was loosened and sent downstream in recurrent jams. In general, the larger rivers did not attain extraordinary stages. The Connecticut River at Hartford peaked at a stage 3.6 feet above ordinary flood level. Direct damage by the flood was relatively small. Snow cover on January 20, at the beginning of the rains, varied from 0.25 inch along the coast to 2.75 inches water equivalent in the northern part of the State. Precipitation between January 24 and 26 exceeded 2.75 inches in only three small areas. Total supply as water in snow and precipitation did not exceed 4.8 inches over any tributary area. Maximum measured flood run-off was 2.7 inches. The flood of June 1938 in New Jersey was the immediate result of a 30-hour rainstorm on June 26-27 that centered along a line extending from Odessa, Del., to Milton, N. J. Storm rainfall exceeded 5 inches over a total area of 2,900 square miles. River stages in the central parts of the storm area rose to levels that

  10. [Light response characteristics of photosynthesis and model comparison of Distylium chinense in different flooding durations].

    Science.gov (United States)

    Liu, Ze-bin; Cheng, Rui-mei; Xiao, Wen-fa; Guo, Quan-shui; Wang, Na

    2015-04-01

    The light responses of photosynthesis of two-year-old Distytum chinense seedlings subjected to a simulated reservoir flooding environment in autumn and winter seasons were measured by using a Li-6400 XT portable photosynthesis system, and the light response curves were fitted and analyzed by three models of the rectangular hyperbola, non-rectangular hyperbola and modified rectangular hyperbola to investigate the applicability of different light response models for the D. chinense in different flooding durations and the adaption regulation of light response parameters to flooding stress. The results showed that the fitting effect of the non-rectangular hyperbola model for light response process of D. chinense under normal growth condition and under short-term flooding (15 days of flooding) was better than that of the other two models, while the fitting effect of the modified rectangular hyperbola model for light response process of D. chinense under longer-term flooding (30, 45 and 60 days of flooding) was better than that of the other two models. The modified rectangular hyperbola model gave the best fitted results of light compensation point (LCP) , maximum net photosynthetic rate (P(n max)) and light saturation point (LSP), and the non-rectangular hyperbola model gave the best fitted result of dark respiration rate (R(d)). The apparent quantum yield (Φ), P(n max) and LSP of D. chinense gradually decreased, and the LCP and R(d) of D. chinense gradually increased in early flooding (30 days), but D. chinense gradually produced adaptability for flooding as the flooding duration continued to increase, and various physiological indexes were gradually stabilized. Thus, this species has adaptability to some degree to the flooding environment.

  11. Introduction to flood control science

    International Nuclear Information System (INIS)

    Lee, Dong U; Ha, Jin Uk; Kim, Dong Ha; Shin, Hong Ryeol; Song, Seok Hwan; Kim, Jin Gyu; Moon, Heon Cheol

    2003-01-01

    This book covers introduction, industrialization disaster such as Bhopal and Chernobyl disaster, earthquake disaster, volcano disaster, avalanche disaster including loss allocation and prevention measures, and natural fire by showing California, Yellowstone park and similarity between fire and flood. It also introduces climate change and disaster, Earth's greenhouse effect and disaster due to current sea level rise, flood damage, drought disaster, famine and drought, prediction of drought, population problems, outlook of world population, and disaster prevention administration system of Korea.

  12. Elk River Watershed - Flood Study

    Science.gov (United States)

    Barnes, C. C.; Byrne, J. M.; MacDonald, R. J.; Lewis, D.

    2014-12-01

    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. Potential flooding from just under 100 (2009 NPRI Reviewed Facility Data Release, Environment Canada) toxic tailings ponds located in Canada increase risk to human safety and the environment. One such geotechnical failure spilt billions of litres of toxic tailings into the Fraser River watershed, British Columbia, when a tailings pond dam breach occurred in August 2014. Damaged and washed out roadways cut access to essential services as seen by the extensive floods that occurred in Saskatchewan and Manitoba in July 2014, and in Southern Alberta in 2013. Recovery efforts from events such as these can be lengthy, and have substantial social and economic impacts both in loss of revenue and cost of repair. The objective of this study is to investigate existing conditions in the Elk River watershed and model potential future hydrological changes that can increase flood risk hazards. By analyzing existing hydrology, meteorology, land cover, land use, economic, and settlement patterns a baseline is established for existing conditions in the Elk River watershed. Coupling the Generate Earth Systems Science (GENESYS) high-resolution spatial hydrometeorological model with flood hazard analysis methodology, high-resolution flood vulnerability base line maps are created using historical climate conditions. Further work in 2015 will examine possible impacts for a range of climate change and land use change scenarios to define changes to future flood risk and vulnerability.

  13. Extreme Maximum Land Surface Temperatures.

    Science.gov (United States)

    Garratt, J. R.

    1992-09-01

    There are numerous reports in the literature of observations of land surface temperatures. Some of these, almost all made in situ, reveal maximum values in the 50°-70°C range, with a few, made in desert regions, near 80°C. Consideration of a simplified form of the surface energy balance equation, utilizing likely upper values of absorbed shortwave flux (1000 W m2) and screen air temperature (55°C), that surface temperatures in the vicinity of 90°-100°C may occur for dry, darkish soils of low thermal conductivity (0.1-0.2 W m1 K1). Numerical simulations confirm this and suggest that temperature gradients in the first few centimeters of soil may reach 0.5°-1°C mm1 under these extreme conditions. The study bears upon the intrinsic interest of identifying extreme maximum temperatures and yields interesting information regarding the comfort zone of animals (including man).

  14. Flood frequency analysis and generation of flood hazard indicator maps in a semi-arid environment, case of Ourika watershed (western High Atlas, Morocco)

    Science.gov (United States)

    El Alaoui El Fels, Abdelhafid; Alaa, Noureddine; Bachnou, Ali; Rachidi, Said

    2018-05-01

    The development of the statistical models and flood risk modeling approaches have seen remarkable improvements in their productivities. Their application in arid and semi-arid regions, particularly in developing countries, can be extremely useful for better assessment and planning of flood risk in order to reduce the catastrophic impacts of this phenomenon. This study focuses on the Setti Fadma region (Ourika basin, Morocco) which is potentially threatened by floods and is subject to climatic and anthropogenic forcing. The study is based on two main axes: (i) the extreme flow frequency analysis, using 12 probability laws adjusted by Maximum Likelihood method and (ii) the generation of the flood risk indicator maps are based on the solution proposed by the Nays2DFlood solver of the Hydrodynamic model of two-dimensional Saint-Venant equations. The study is used as a spatial high-resolution digital model (Lidar) in order to get the nearest hydrological simulation of the reality. The results showed that the GEV is the most appropriate law of the extreme flows estimation for different return periods. Taking into consideration the mapping of 100-year flood area, the study revealed that the fluvial overflows extent towards the banks of Ourika and consequently, affects some living areas, cultivated fields and the roads that connects the valley to the city of Marrakech. The aim of this study is to propose new technics of the flood risk management allowing a better planning of the flooded areas.

  15. Cyber Surveillance for Flood Disasters

    Directory of Open Access Journals (Sweden)

    Shi-Wei Lo

    2015-01-01

    Full Text Available Regional heavy rainfall is usually caused by the influence of extreme weather conditions. Instant heavy rainfall often results in the flooding of rivers and the neighboring low-lying areas, which is responsible for a large number of casualties and considerable property loss. The existing precipitation forecast systems mostly focus on the analysis and forecast of large-scale areas but do not provide precise instant automatic monitoring and alert feedback for individual river areas and sections. Therefore, in this paper, we propose an easy method to automatically monitor the flood object of a specific area, based on the currently widely used remote cyber surveillance systems and image processing methods, in order to obtain instant flooding and waterlogging event feedback. The intrusion detection mode of these surveillance systems is used in this study, wherein a flood is considered a possible invasion object. Through the detection and verification of flood objects, automatic flood risk-level monitoring of specific individual river segments, as well as the automatic urban inundation detection, has become possible. The proposed method can better meet the practical needs of disaster prevention than the method of large-area forecasting. It also has several other advantages, such as flexibility in location selection, no requirement of a standard water-level ruler, and a relatively large field of view, when compared with the traditional water-level measurements using video screens. The results can offer prompt reference for appropriate disaster warning actions in small areas, making them more accurate and effective.

  16. Scales of Natural Flood Management

    Science.gov (United States)

    Nicholson, Alex; Quinn, Paul; Owen, Gareth; Hetherington, David; Piedra Lara, Miguel; O'Donnell, Greg

    2016-04-01

    The scientific field of Natural flood Management (NFM) is receiving much attention and is now widely seen as a valid solution to sustainably manage flood risk whilst offering significant multiple benefits. However, few examples exist looking at NFM on a large scale (>10km2). Well-implemented NFM has the effect of restoring more natural catchment hydrological and sedimentological processes, which in turn can have significant flood risk and WFD benefits for catchment waterbodies. These catchment scale improvements in-turn allow more 'natural' processes to be returned to rivers and streams, creating a more resilient system. Although certain NFM interventions may appear distant and disconnected from main stem waterbodies, they will undoubtedly be contributing to WFD at the catchment waterbody scale. This paper offers examples of NFM, and explains how they can be maximised through practical design across many scales (from feature up to the whole catchment). New tools to assist in the selection of measures and their location, and to appreciate firstly, the flooding benefit at the local catchment scale and then show a Flood Impact Model that can best reflect the impacts of local changes further downstream. The tools will be discussed in the context of our most recent experiences on NFM projects including river catchments in the north east of England and in Scotland. This work has encouraged a more integrated approach to flood management planning that can use both traditional and novel NFM strategies in an effective and convincing way.

  17. Flooding Effect on Earth Walls

    Directory of Open Access Journals (Sweden)

    Meysam Banimahd

    2010-12-01

    Full Text Available Earth building is a sustainable, environmentally friendly and economical method of construction that has been used worldwide for many centuries. For the past three decades, earth has seen a revival as a building material for a modern construction method due to its benefits in terms of low carbon content, low cost and energy involved during construction, as well as the fact that it is a sustainable technology of building. Climate change is influencing precipitation levels and patterns around the world, and as a consequence, flood risk is increasing rapidly. When flooding occurs, earth buildings are exposed to water by submersion, causing an increase in the degree of saturation of the earth structures and therefore a decrease of the suction between particles. This study investigated the effect of cycles of flooding (consecutive events of flooding followed by dry periods on earth walls. A series of characterization tests were carried out to obtain the physical and mechanical properties of the studied earth material. In a second stage, Flooding Simulation Tests (FST were performed to explore the earth walls’ response to repeated flooding events. The results obtained for the tested earth wall/samples with reinforced material (straw reveal hydraulic hysteresis when wall/samples are subject to cycles of wetting and drying.

  18. Lightning activity, rainfall and flash flooding – occasional or interrelated events? A case study in the island of Crete

    Directory of Open Access Journals (Sweden)

    A. G. Koutroulis

    2012-04-01

    Full Text Available The majority of cyclones passing over Crete in late autumn to early winter originate from southwest, west and northwest and are of varying size and intensity. A number of these cyclones cause flash floods. The present study reports the possible relationships between lighting activity and high precipitation related to flash flood events. In this study an attempt was made to correlate the lightning number and location, recorded by the ZEUS lightning detection system, with the rainfall characteristics for sixteen rain events (4 flood and 12 non-flood events on the island of Crete, during the period 2008–2009. Spatiotemporal analysis of rain and rain rate with flash count was performed with respect to distance (radius of flashes from raingauge location at various temporal scales, in order to examine the correlation of accumulated rainfall and lightning activity. The maximum attained statistical significant correlation was obtained within a circular area of an average radius of 15 km around the raingauge, and an average time lag of flash count prior precipitation accumulation of 15 min. The maximum correlation between the lightning and rainfall data is obtained for shorter time lags for the flood events (15 min than the non-flood events (25 min, that could reflect the faster propagation of flood triggering storms due to high convective activity. Results show increased lightning activity occurring during flood triggering storms, by an average of four times higher. Furthermore, there is evidence that the number of flashes that occur during a precipitation event is related to precipitation depth when the latter is adequate to produce a flood event. Differences between flood and non-flood producing storms need to be further assessed by analyzing more independent parameters, including the synoptic conditions and dominant flash flood hydrological generating processes.

  19. Constructing risks – Internalisation of flood risks in the flood risk management plan

    NARCIS (Netherlands)

    Roos, Matthijs; Hartmann, T.; Spit, T.J.M.; Johann, Georg

    Traditional flood protection methods have focused efforts on different measures to keep water out of floodplains. However, the European Flood Directive challenges this paradigm (Hartmann and Driessen, 2013). Accordingly, flood risk management plans should incorporate measures brought about by

  20. Hydrogeomorphic Investigation of the 2015 Atacama Floods, Northern Chile

    Science.gov (United States)

    Wilcox, A. C.; Escauriaza, C. R.; Agredano, R., Jr.; Mignot, E.; Gironas, J. A.; Cienfuegos, R.; Mao, L.

    2015-12-01

    In March 2015 unusual atmospheric conditions over the Atacama Desert of northern Chile, the driest area on Earth outside of Antarctica, produced many years worth of rainfall in a 24-hour period. The resulting sediment-rich floods caused dozens of deaths and/or disappearances, over $1 billion in estimated damage, and widespread geomorphic change. Here we describe the hydrologic and geomorphic drivers and responses to the 2015 Atacama floods, including characterization of the hydrologic forcing, water and sediment routing from source areas in the upper watershed to the outlet at the Pacific Ocean, and urban flooding impacts of this event. In a region where few direct measurements of precipitation and discharge during these events are available, we combined hydrologic and hydraulic modeling with field and aerial photograph interpretation of sediment sources and geomorphic change. A remarkable element of the flood, particularly with respect to its effects on urban areas, was its high sediment load. Despite widespread hillslope erosion in the form of rilling and gullying initiated by overland flow, sediment from these sources typically did not reach valley bottoms, and only limited, small-scale mass wasting was observed. Field observations indicated that the sediment load was primarily derived from dramatic erosion of channel bed, bank, and floodplain material (i.e., valley fill). In the coastal city of Chañaral, flooding of the Salado River produced maximum water depths over 6 m, meters-thick mud deposition in buildings and along city streets, flow velocities larger than 8 m/s, and coastal erosion. Broader implications of studying the Atacama flooding include hazard reduction, the history of copper mining and more than five decades of contamination in many of the affected watersheds, and the Atacama's status as a terrestrial analog for Mars.

  1. Feasibility of estimating generalized extreme-value distribution of floods

    International Nuclear Information System (INIS)

    Ferreira de Queiroz, Manoel Moises

    2004-01-01

    Flood frequency analysis by generalized extreme-value probability distribution (GEV) has found increased application in recent years, given its flexibility in dealing with the three asymptotic forms of extreme distribution derived from different initial probability distributions. Estimation of higher quantiles of floods is usually accomplished by extrapolating one of the three inverse forms of GEV distribution fitted to the experimental data for return periods much higher than those actually observed. This paper studies the feasibility of fitting GEV distribution by moments of linear combinations of higher order statistics (LH moments) using synthetic annual flood series with varying characteristics and lengths. As the hydrologic events in nature such as daily discharge occur with finite values, their annual maximums are expected to follow the asymptotic form of the limited GEV distribution. Synthetic annual flood series were thus obtained from the stochastic sequences of 365 daily discharges generated by Monte Carlo simulation on the basis of limited probability distribution underlying the limited GEV distribution. The results show that parameter estimation by LH moments of this distribution, fitted to annual flood samples of less than 100-year length derived from initial limited distribution, may indicate any form of extreme-value distribution, not just the limited form as expected, and with large uncertainty in fitted parameters. A frequency analysis, on the basis of GEV distribution and LH moments, of annual flood series of lengths varying between 13 and 73 years observed at 88 gauge stations on Parana River in Brazil, indicated all the three forms of GEV distribution.(Author)

  2. Challenges of Modeling Flood Risk at Large Scales

    Science.gov (United States)

    Guin, J.; Simic, M.; Rowe, J.

    2009-04-01

    algorithm propagates the flows for each simulated event. The model incorporates a digital terrain model (DTM) at 10m horizontal resolution, which is used to extract flood plain cross-sections such that a one-dimensional hydraulic model can be used to estimate extent and elevation of flooding. In doing so the effect of flood defenses in mitigating floods are accounted for. Finally a suite of vulnerability relationships have been developed to estimate flood losses for a portfolio of properties that are exposed to flood hazard. Historical experience indicates that a for recent floods in Great Britain more than 50% of insurance claims occur outside the flood plain and these are primarily a result of excess surface flow, hillside flooding, flooding due to inadequate drainage. A sub-component of the model addresses this issue by considering several parameters that best explain the variability of claims off the flood plain. The challenges of modeling such a complex phenomenon at a large scale largely dictate the choice of modeling approaches that need to be adopted for each of these model components. While detailed numerically-based physical models exist and have been used for conducting flood hazard studies, they are generally restricted to small geographic regions. In a probabilistic risk estimation framework like our current model, a blend of deterministic and statistical techniques have to be employed such that each model component is independent, physically sound and is able to maintain the statistical properties of observed historical data. This is particularly important because of the highly non-linear behavior of the flooding process. With respect to vulnerability modeling, both on and off the flood plain, the challenges include the appropriate scaling of a damage relationship when applied to a portfolio of properties. This arises from the fact that the estimated hazard parameter used for damage assessment, namely maximum flood depth has considerable uncertainty. The

  3. System for memorizing maximum values

    Science.gov (United States)

    Bozeman, Richard J., Jr.

    1992-08-01

    The invention discloses a system capable of memorizing maximum sensed values. The system includes conditioning circuitry which receives the analog output signal from a sensor transducer. The conditioning circuitry rectifies and filters the analog signal and provides an input signal to a digital driver, which may be either linear or logarithmic. The driver converts the analog signal to discrete digital values, which in turn triggers an output signal on one of a plurality of driver output lines n. The particular output lines selected is dependent on the converted digital value. A microfuse memory device connects across the driver output lines, with n segments. Each segment is associated with one driver output line, and includes a microfuse that is blown when a signal appears on the associated driver output line.

  4. Remarks on the maximum luminosity

    Science.gov (United States)

    Cardoso, Vitor; Ikeda, Taishi; Moore, Christopher J.; Yoo, Chul-Moon

    2018-04-01

    The quest for fundamental limitations on physical processes is old and venerable. Here, we investigate the maximum possible power, or luminosity, that any event can produce. We show, via full nonlinear simulations of Einstein's equations, that there exist initial conditions which give rise to arbitrarily large luminosities. However, the requirement that there is no past horizon in the spacetime seems to limit the luminosity to below the Planck value, LP=c5/G . Numerical relativity simulations of critical collapse yield the largest luminosities observed to date, ≈ 0.2 LP . We also present an analytic solution to the Einstein equations which seems to give an unboundedly large luminosity; this will guide future numerical efforts to investigate super-Planckian luminosities.

  5. Maximum mutual information regularized classification

    KAUST Repository

    Wang, Jim Jing-Yan

    2014-09-07

    In this paper, a novel pattern classification approach is proposed by regularizing the classifier learning to maximize mutual information between the classification response and the true class label. We argue that, with the learned classifier, the uncertainty of the true class label of a data sample should be reduced by knowing its classification response as much as possible. The reduced uncertainty is measured by the mutual information between the classification response and the true class label. To this end, when learning a linear classifier, we propose to maximize the mutual information between classification responses and true class labels of training samples, besides minimizing the classification error and reducing the classifier complexity. An objective function is constructed by modeling mutual information with entropy estimation, and it is optimized by a gradient descend method in an iterative algorithm. Experiments on two real world pattern classification problems show the significant improvements achieved by maximum mutual information regularization.

  6. Scintillation counter, maximum gamma aspect

    International Nuclear Information System (INIS)

    Thumim, A.D.

    1975-01-01

    A scintillation counter, particularly for counting gamma ray photons, includes a massive lead radiation shield surrounding a sample-receiving zone. The shield is disassembleable into a plurality of segments to allow facile installation and removal of a photomultiplier tube assembly, the segments being so constructed as to prevent straight-line access of external radiation through the shield into radiation-responsive areas. Provisions are made for accurately aligning the photomultiplier tube with respect to one or more sample-transmitting bores extending through the shield to the sample receiving zone. A sample elevator, used in transporting samples into the zone, is designed to provide a maximum gamma-receiving aspect to maximize the gamma detecting efficiency. (U.S.)

  7. Maximum mutual information regularized classification

    KAUST Repository

    Wang, Jim Jing-Yan; Wang, Yi; Zhao, Shiguang; Gao, Xin

    2014-01-01

    In this paper, a novel pattern classification approach is proposed by regularizing the classifier learning to maximize mutual information between the classification response and the true class label. We argue that, with the learned classifier, the uncertainty of the true class label of a data sample should be reduced by knowing its classification response as much as possible. The reduced uncertainty is measured by the mutual information between the classification response and the true class label. To this end, when learning a linear classifier, we propose to maximize the mutual information between classification responses and true class labels of training samples, besides minimizing the classification error and reducing the classifier complexity. An objective function is constructed by modeling mutual information with entropy estimation, and it is optimized by a gradient descend method in an iterative algorithm. Experiments on two real world pattern classification problems show the significant improvements achieved by maximum mutual information regularization.

  8. Do flood risk perceptions provide useful insights for flood risk management? Findings from central Vietnam

    OpenAIRE

    Bubeck, P.; Botzen, W.J.W.; Suu, L.T.T.; Aerts, J.C.J.H.

    2012-01-01

    Following the renewed attention for non-structural flood risk reduction measures implemented at the household level, there has been an increased interest in individual flood risk perceptions. The reason for this is the commonly-made assumption that flood risk perceptions drive the motivation of individuals to undertake flood risk mitigation measures, as well as the public's demand for flood protection, and therefore provide useful insights for flood risk management. This study empirically exa...

  9. Flood frequency analysis for nonstationary annual peak records in an urban drainage basin

    Science.gov (United States)

    Villarini, G.; Smith, J.A.; Serinaldi, F.; Bales, J.; Bates, P.D.; Krajewski, W.F.

    2009-01-01

    Flood frequency analysis in urban watersheds is complicated by nonstationarities of annual peak records associated with land use change and evolving urban stormwater infrastructure. In this study, a framework for flood frequency analysis is developed based on the Generalized Additive Models for Location, Scale and Shape parameters (GAMLSS), a tool for modeling time series under nonstationary conditions. GAMLSS is applied to annual maximum peak discharge records for Little Sugar Creek, a highly urbanized watershed which drains the urban core of Charlotte, North Carolina. It is shown that GAMLSS is able to describe the variability in the mean and variance of the annual maximum peak discharge by modeling the parameters of the selected parametric distribution as a smooth function of time via cubic splines. Flood frequency analyses for Little Sugar Creek (at a drainage area of 110 km2) show that the maximum flow with a 0.01-annual probability (corresponding to 100-year flood peak under stationary conditions) over the 83-year record has ranged from a minimum unit discharge of 2.1 m3 s- 1 km- 2 to a maximum of 5.1 m3 s- 1 km- 2. An alternative characterization can be made by examining the estimated return interval of the peak discharge that would have an annual exceedance probability of 0.01 under the assumption of stationarity (3.2 m3 s- 1 km- 2). Under nonstationary conditions, alternative definitions of return period should be adapted. Under the GAMLSS model, the return interval of an annual peak discharge of 3.2 m3 s- 1 km- 2 ranges from a maximum value of more than 5000 years in 1957 to a minimum value of almost 8 years for the present time (2007). The GAMLSS framework is also used to examine the links between population trends and flood frequency, as well as trends in annual maximum rainfall. These analyses are used to examine evolving flood frequency over future decades. ?? 2009 Elsevier Ltd.

  10. Flood frequency analysis for nonstationary annual peak records in an urban drainage basin

    Science.gov (United States)

    Villarini, Gabriele; Smith, James A.; Serinaldi, Francesco; Bales, Jerad; Bates, Paul D.; Krajewski, Witold F.

    2009-08-01

    Flood frequency analysis in urban watersheds is complicated by nonstationarities of annual peak records associated with land use change and evolving urban stormwater infrastructure. In this study, a framework for flood frequency analysis is developed based on the Generalized Additive Models for Location, Scale and Shape parameters (GAMLSS), a tool for modeling time series under nonstationary conditions. GAMLSS is applied to annual maximum peak discharge records for Little Sugar Creek, a highly urbanized watershed which drains the urban core of Charlotte, North Carolina. It is shown that GAMLSS is able to describe the variability in the mean and variance of the annual maximum peak discharge by modeling the parameters of the selected parametric distribution as a smooth function of time via cubic splines. Flood frequency analyses for Little Sugar Creek (at a drainage area of 110km) show that the maximum flow with a 0.01-annual probability (corresponding to 100-year flood peak under stationary conditions) over the 83-year record has ranged from a minimum unit discharge of 2.1mskm to a maximum of 5.1mskm. An alternative characterization can be made by examining the estimated return interval of the peak discharge that would have an annual exceedance probability of 0.01 under the assumption of stationarity (3.2mskm). Under nonstationary conditions, alternative definitions of return period should be adapted. Under the GAMLSS model, the return interval of an annual peak discharge of 3.2mskm ranges from a maximum value of more than 5000 years in 1957 to a minimum value of almost 8 years for the present time (2007). The GAMLSS framework is also used to examine the links between population trends and flood frequency, as well as trends in annual maximum rainfall. These analyses are used to examine evolving flood frequency over future decades.

  11. Hurricane coastal flood analysis using multispectral spectral images

    Science.gov (United States)

    Ogashawara, I.; Ferreira, C.; Curtarelli, M. P.

    2013-12-01

    Flooding is one of the main hazards caused by extreme events such as hurricanes and tropical storms. Therefore, flood maps are a crucial tool to support policy makers, environmental managers and other government agencies for emergency management, disaster recovery and risk reduction planning. However traditional flood mapping methods rely heavily on the interpolation of hydrodynamic models results, and most recently, the extensive collection of field data. These methods are time-consuming, labor intensive, and costly. Efficient and fast response alternative methods should be developed in order to improve flood mapping, and remote sensing has been proved as a valuable tool for this application. Our goal in this paper is to introduce a novel technique based on spectral analysis in order to aggregate knowledge and information to map coastal flood areas. For this purpose we used the Normalized Diference Water Index (NDWI) which was derived from two the medium resolution LANDSAT/TM 5 surface reflectance product from the LANDSAT climate data record (CDR). This product is generated from specialized software called Landsat Ecosystem Disturbance Adaptive Processing System (LEDAPS). We used the surface reflectance products acquired before and after the passage of Hurricane Ike for East Texas in September of 2008. We used as end member a classification of estimated flooded area based on the United States Geological Survey (USGS) mobile storm surge network that was deployed for Hurricane Ike. We used a dataset which consisted of 59 water levels recording stations. The estimated flooded area was delineated interpolating the maximum surge in each location using a spline with barriers method with high tension and a 30 meter Digital Elevation Model (DEM) from the National Elevation Dataset (NED). Our results showed that, in the flooded area, the NDWI values decreased after the hurricane landfall on average from 0.38 to 0.18 and the median value decreased from 0.36 to 0.2. However

  12. Drivers of flood damage on event level

    DEFF Research Database (Denmark)

    Kreibich, H.; Aerts, J. C. J. H.; Apel, H.

    2016-01-01

    Flood risk is dynamic and influenced by many processes related to hazard, exposure and vulnerability. Flood damage increased significantly over the past decades, however, resulting overall economic loss per event is an aggregated indicator and it is difficult to attribute causes to this increasing...... trend. Much has been learned about damaging processes during floods at the micro-scale, e.g. building level. However, little is known about the main factors determining the amount of flood damage on event level. Thus, we analyse and compare paired flood events, i.e. consecutive, similar damaging floods...... example are the 2002 and 2013 floods in the Elbe and Danube catchments in Germany. The 2002 flood caused the highest economic damage (EUR 11600 million) due to a natural hazard event in Germany. Damage was so high due to extreme flood hazard triggered by extreme precipitation and a high number...

  13. Nonlinear Filtering Effects of Reservoirs on Flood Frequency Curves at the Regional Scale: RESERVOIRS FILTER FLOOD FREQUENCY CURVES

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wei; Li, Hong-Yi; Leung, Lai-Yung; Yigzaw, Wondmagegn Y.; Zhao, Jianshi; Lu, Hui; Deng, Zhiqun; Demissie, Yonas; Bloschl, Gunter

    2017-10-01

    Anthropogenic activities, e.g., reservoir operation, may alter the characteristics of Flood Frequency Curve (FFC) and challenge the basic assumption of stationarity used in flood frequency analysis. This paper presents a combined data-modeling analysis of the nonlinear filtering effects of reservoirs on the FFCs over the contiguous United States. A dimensionless Reservoir Impact Index (RII), defined as the total upstream reservoir storage capacity normalized by the annual streamflow volume, is used to quantify reservoir regulation effects. Analyses are performed for 388 river stations with an average record length of 50 years. The first two moments of the FFC, mean annual maximum flood (MAF) and coefficient of variations (CV), are calculated for the pre- and post-dam periods and compared to elucidate the reservoir regulation effects as a function of RII. It is found that MAF generally decreases with increasing RII but stabilizes when RII exceeds a threshold value, and CV increases with RII until a threshold value beyond which CV decreases with RII. The processes underlying the nonlinear threshold behavior of MAF and CV are investigated using three reservoir models with different levels of complexity. All models capture the non-linear relationships of MAF and CV with RII, suggesting that the basic flood control function of reservoirs is key to the non-linear relationships. The relative roles of reservoir storage capacity, operation objectives, available storage prior to a flood event, and reservoir inflow pattern are systematically investigated. Our findings may help improve flood-risk assessment and mitigation in regulated river systems at the regional scale.

  14. Combined fluvial and pluvial urban flood hazard analysis: method development and application to Can Tho City, Mekong Delta, Vietnam

    Science.gov (United States)

    Apel, H.; Trepat, O. M.; Hung, N. N.; Chinh, D. T.; Merz, B.; Dung, N. V.

    2015-08-01

    Many urban areas experience both fluvial and pluvial floods, because locations next to rivers are preferred settlement areas, and the predominantly sealed urban surface prevents infiltration and facilitates surface inundation. The latter problem is enhanced in cities with insufficient or non-existent sewer systems. While there are a number of approaches to analyse either fluvial or pluvial flood hazard, studies of combined fluvial and pluvial flood hazard are hardly available. Thus this study aims at the analysis of fluvial and pluvial flood hazard individually, but also at developing a method for the analysis of combined pluvial and fluvial flood hazard. This combined fluvial-pluvial flood hazard analysis is performed taking Can Tho city, the largest city in the Vietnamese part of the Mekong Delta, as example. In this tropical environment the annual monsoon triggered floods of the Mekong River can coincide with heavy local convective precipitation events causing both fluvial and pluvial flooding at the same time. Fluvial flood hazard was estimated with a copula based bivariate extreme value statistic for the gauge Kratie at the upper boundary of the Mekong Delta and a large-scale hydrodynamic model of the Mekong Delta. This provided the boundaries for 2-dimensional hydrodynamic inundation simulation for Can Tho city. Pluvial hazard was estimated by a peak-over-threshold frequency estimation based on local rain gauge data, and a stochastic rain storm generator. Inundation was simulated by a 2-dimensional hydrodynamic model implemented on a Graphical Processor Unit (GPU) for time-efficient flood propagation modelling. All hazards - fluvial, pluvial and combined - were accompanied by an uncertainty estimation considering the natural variability of the flood events. This resulted in probabilistic flood hazard maps showing the maximum inundation depths for a selected set of probabilities of occurrence, with maps showing the expectation (median) and the uncertainty by

  15. State-of-the-art for evaluating the potential impact of flooding on a radioactive waste repository

    International Nuclear Information System (INIS)

    1980-01-01

    This report is a review of the state-of-the-art for evaluating the potential impact of flooding on a deep radioactive-waste repository, namely, for predicting the future occurrence of catastrophic flooding and for estimating the effect of such flooding on waste containment characteristics. Several detrimental effects are identified: flooding can increase groundwater seepage velocities through a repository within the framework of the existing hydrologic system and thus increase the rate of radioactive-waste leakage to the biosphere; flooding may alter repository hydrology by reversing flow gradients, relocating sources of groundwater recharge and discharge, or shortening seepage paths, thereby producing unpredictable leakage; saturation of a vadose-zone repository during flooding can increase groundwater seepage velocities by several orders of magnitude; and flooding can damage repository-media containment properties by inducing seismic or chemical instability or increasing fracture permeability in relatively shallow repository rock as a result of redistributing in-situ stresses. Short-term flooding frequency and magnitude can be predicted statistically by analyzing historical records of flooding. However, long-term flooding events that could damage a permanent repository cannot be predicted with confidence because the geologic record is neither unique nor sufficienly complete for statistical analysis. It is more important to identify parameters characterizing containment properties (such as permeability, groundwater gradient, and shortest seepage path length to the biosphere) that could be affected by future flooding, estimate the maximum magnitude of flooding that could occur within the life of the repository by examining the geologic record, and determine the impact such flooding could have on the parameter values

  16. Flooding Mechanism in Vertical Flow

    International Nuclear Information System (INIS)

    Ronny-Dwi Agussulistyo; Indarto

    2000-01-01

    This research was carried out to investigate the mechanism of flooding ina vertical liquid-gas counter current flow, along two meter length of thetube. The tube use both circular and square tube, a cross section of squaretube was made the same as a cross section of circular tube with one inchdiameter tube. The liquid enters the tube, passes through a porous wall inletand a groove inlet in a distributor and it flows downwards through a liquidoutlet in a collector. The gas is being introduced at the bottom of the tube,it flows upwards through nozzle in the collector. The results of researchshowed that the flooding occurs earlier in the circular tube than in thesquare tube, either uses a porous wall inlet or a groove inlet. In the squaretube , onset of the flooding occurs at the top of the tube, in front ofliquid injection, it is related to the formation of a film wave, just belowthe liquid feed. Whereas in the circular tube, onset of the flooding occursfrom the bottom of the tube, at the liquid outlet, it is related to theexpand of the film wave. However, in the circular tube with the groove inlet,for the higher liquid flow rate, onset of the flooding from the top, like inthe square tube. (author)

  17. Maximum entropy and Bayesian methods

    International Nuclear Information System (INIS)

    Smith, C.R.; Erickson, G.J.; Neudorfer, P.O.

    1992-01-01

    Bayesian probability theory and Maximum Entropy methods are at the core of a new view of scientific inference. These 'new' ideas, along with the revolution in computational methods afforded by modern computers allow astronomers, electrical engineers, image processors of any type, NMR chemists and physicists, and anyone at all who has to deal with incomplete and noisy data, to take advantage of methods that, in the past, have been applied only in some areas of theoretical physics. The title workshops have been the focus of a group of researchers from many different fields, and this diversity is evident in this book. There are tutorial and theoretical papers, and applications in a very wide variety of fields. Almost any instance of dealing with incomplete and noisy data can be usefully treated by these methods, and many areas of theoretical research are being enhanced by the thoughtful application of Bayes' theorem. Contributions contained in this volume present a state-of-the-art overview that will be influential and useful for many years to come

  18. A sequential model to link contextual risk, perception and public support for flood adaptation policy.

    Science.gov (United States)

    Shao, Wanyun; Xian, Siyuan; Lin, Ning; Small, Mitchell J

    2017-10-01

    The economic damage from coastal flooding has dramatically increased over the past several decades, owing to rapid development in shoreline areas and possible effects of climate change. To respond to these trends, it is imperative for policy makers to understand individuals' support for flood adaptation policy. Using original survey data for all coastal counties of the United States Gulf Coast merged with contextual data on flood risk, this study investigates coastal residents' support for two adaptation policy measures: incentives for relocation and funding for educational programs on emergency planning and evacuation. Specifically, this study explores the interactive relationships among contextual flood risks, perceived flood risks and policy support for flood adaptation, with the effects of social-demographic variables being controlled. Age, gender, race and partisanship are found to significantly affect individuals' policy support for both adaptation measures. The contextual flooding risks, indicated by distance from the coast, maximum wind speed and peak height of storm surge associated with the last hurricane landfall, and percentage of high-risk flood zone per county, are shown to impact one's perceptions of risk, which in turn influence one's support for both policy measures. The key finding -risk perception mediates the impact of contextual risk conditions on public support for flood management policies - highlights the need to ensure that the public is well informed by the latest scientific, engineering and economic knowledge. To achieve this, more information on current and future flood risks and options available for mitigation as well as risk communication tools are needed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Ohio River backwater flood-inundation maps for the Saline and Wabash Rivers in southern Illinois

    Science.gov (United States)

    Murphy, Elizabeth A.; Sharpe, Jennifer B.; Soong, David T.

    2012-01-01

    Digital flood-inundation maps for the Saline and Wabash Rivers referenced to elevations on the Ohio River in southern Illinois were created by the U.S. Geological Survey (USGS). The inundation maps, accessible through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent of flooding corresponding to selected water levels (gage heights) at the USGS streamgage at Ohio River at Old Shawneetown, Illinois-Kentucky (station number 03381700). Current gage height and flow conditions at this USGS streamgage may be obtained on the Internet at http://waterdata.usgs.gov/usa/nwis/uv?03381700. In addition, this streamgage is incorporated into the Advanced Hydrologic Prediction Service (AHPS) flood warning system (http://water.weather.gov/ahps/) by the National Weather Service (NWS). The NWS forecasts flood hydrographs at many places that are often co-located at USGS streamgages. That NWS forecasted peak-stage information, also shown on the Ohio River at Old Shawneetown inundation Web site, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, eight water-surface elevations were mapped at 5-foot (ft) intervals referenced to the streamgage datum ranging from just above the NWS Action Stage (31 ft) to above the maximum historical gage height (66 ft). The elevations of the water surfaces were compared to a Digital Elevation Model (DEM) by using a Geographic Information System (GIS) in order to delineate the area flooded at each water level. These maps, along with information on the Internet regarding current gage heights from USGS streamgages and forecasted stream stages from the NWS, provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for post-flood recovery efforts.

  20. Effects of Flood Control Strategies on Flood Resilience Under Sociohydrological Disturbances

    Science.gov (United States)

    Sung, Kyungmin; Jeong, Hanseok; Sangwan, Nikhil; Yu, David J.

    2018-04-01

    A community capacity to cope with flood hazards, or community flood resilience, emerges from the interplay of hydrological and social processes. This interplay can be significantly influenced by the flood control strategy adopted by a society, i.e., how a society sets its desired flood protection level and strives to achieve this goal. And this interplay can be further complicated by rising land-sea level differences, seasonal water level fluctuations, and economic change. But not much research has been done on how various forms of flood control strategies affect human-flood interactions under these disturbances and therefore flood resilience in the long run. The current study is an effort to address these issues by developing a conceptual model of human-flood interaction mediated by flood control strategies. Our model extends the existing model of Yu et al. (2017), who investigated the flood resilience of a community-based flood protection system in coastal Bangladesh. The major extensions made in this study are inclusions of various forms of flood control strategies (both adaptive and nonadaptive ones), the challenge of rising land-sea level differences, and various high tide level scenarios generated from modifying the statistical variances and averages. Our results show that adaptive forms of flood control strategies tend to outperform nonadaptive ones for maintaining the model community's flood protection system. Adaptive strategies that dynamically adjust target flood protection levels through close monitoring of flood damages and social memories of flood risk can help the model community deal with various disturbances.

  1. Spatial Analysis of High-Resolution Radar Rainfall and Citizen-Reported Flash Flood Data in Ultra-Urban New York City

    Directory of Open Access Journals (Sweden)

    Brianne Smith

    2017-09-01

    Full Text Available New York City (NYC is an ultra-urban region, with over 50% impervious cover and buried stream channels. Traditional flood studies rely on the presence of stream gages to detect flood stage and discharge, but these methods cannot be used in ultra-urban areas. Here we create a high-resolution radar rainfall dataset for NYC and utilize citizen and expert reports of flooding throughout the city to study flash flooding in NYC. Results indicate that interactions between the urban area and land–sea boundary have an important impact on the spatial variability of both heavy rainfall and flooding, sometimes in contrast to results obtained for other cities. Top days of daily and hourly rainfall exhibit a rainfall maximum over the city center and an extended region of higher rainfall downwind of the city. The mechanism for flooding appears to vary across the city, with high groundwater tables influencing more coastal areas and high rain rates or large rain volumes influencing more inland areas. There is also a strong relationship between sewer type and flood frequency, with fewer floods observed in combined sewer areas. Flooding is driven by maximum one-hour to one-day rainfall, which is often substantially less rain than observed for the city-wide daily maximum.

  2. Comparing flood loss models of different complexity

    Science.gov (United States)

    Schröter, Kai; Kreibich, Heidi; Vogel, Kristin; Riggelsen, Carsten; Scherbaum, Frank; Merz, Bruno

    2013-04-01

    Any deliberation on flood risk requires the consideration of potential flood losses. In particular, reliable flood loss models are needed to evaluate cost-effectiveness of mitigation measures, to assess vulnerability, for comparative risk analysis and financial appraisal during and after floods. In recent years, considerable improvements have been made both concerning the data basis and the methodological approaches used for the development of flood loss models. Despite of that, flood loss models remain an important source of uncertainty. Likewise the temporal and spatial transferability of flood loss models is still limited. This contribution investigates the predictive capability of different flood loss models in a split sample cross regional validation approach. For this purpose, flood loss models of different complexity, i.e. based on different numbers of explaining variables, are learned from a set of damage records that was obtained from a survey after the Elbe flood in 2002. The validation of model predictions is carried out for different flood events in the Elbe and Danube river basins in 2002, 2005 and 2006 for which damage records are available from surveys after the flood events. The models investigated are a stage-damage model, the rule based model FLEMOps+r as well as novel model approaches which are derived using data mining techniques of regression trees and Bayesian networks. The Bayesian network approach to flood loss modelling provides attractive additional information concerning the probability distribution of both model predictions and explaining variables.

  3. 2011 floods of the central United States

    Science.gov (United States)

    ,

    2013-01-01

    The Central United States experienced record-setting flooding during 2011, with floods that extended from headwater streams in the Rocky Mountains, to transboundary rivers in the upper Midwest and Northern Plains, to the deep and wide sand-bedded lower Mississippi River. The U.S. Geological Survey (USGS), as part of its mission, collected extensive information during and in the aftermath of the 2011 floods to support scientific analysis of the origins and consequences of extreme floods. The information collected for the 2011 floods, combined with decades of past data, enables scientists and engineers from the USGS to provide syntheses and scientific analyses to inform emergency managers, planners, and policy makers about life-safety, economic, and environmental-health issues surrounding flood hazards for the 2011 floods and future floods like it. USGS data, information, and scientific analyses provide context and understanding of the effect of floods on complex societal issues such as ecosystem and human health, flood-plain management, climate-change adaptation, economic security, and the associated policies enacted for mitigation. Among the largest societal questions is "How do we balance agricultural, economic, life-safety, and environmental needs in and along our rivers?" To address this issue, many scientific questions have to be answered including the following: * How do the 2011 weather and flood conditions compare to the past weather and flood conditions and what can we reasonably expect in the future for flood magnitudes?

  4. Flood Water Segmentation from Crowdsourced Images

    Science.gov (United States)

    Nguyen, J. K.; Minsker, B. S.

    2017-12-01

    In the United States, 176 people were killed by flooding in 2015. Along with the loss of human lives is the economic cost which is estimated to be $4.5 billion per flood event. Urban flooding has become a recent concern due to the increase in population, urbanization, and global warming. As more and more people are moving into towns and cities with infrastructure incapable of coping with floods, there is a need for more scalable solutions for urban flood management.The proliferation of camera-equipped mobile devices have led to a new source of information for flood research. In-situ photographs captured by people provide information at the local level that remotely sensed images fail to capture. Applications of crowdsourced images to flood research required understanding the content of the image without the need for user input. This paper addresses the problem of how to automatically segment a flooded and non-flooded region in crowdsourced images. Previous works require two images taken at similar angle and perspective of the location when it is flooded and when it is not flooded. We examine three different algorithms from the computer vision literature that are able to perform segmentation using a single flood image without these assumptions. The performance of each algorithm is evaluated on a collection of labeled crowdsourced flood images. We show that it is possible to achieve a segmentation accuracy of 80% using just a single image.

  5. Behaviour of liquid films and flooding in counter-current two-phase flow, (1)

    International Nuclear Information System (INIS)

    Suzuki, Shin-ichi; Ueda, Tatsuhiro.

    1978-01-01

    This paper reports on the results of study of the behavior of liquid film and flooding in counter-current two phase flow, and the flow speed of gas phase was measured over the wide ranges of tube diameter, tube length, amount of liquid flow, viscosity and surface tension. Liquid samples used for this experiment were water, glycerol, and second octyl alcohol. The phenomena were observed with a high speed camera. The maximum thickness of liquid film was measured, and the effects of various factors on the flooding were investigated. The results of investigation were as follows. The big waves which cause the flooding were developed by the interaction of one of the waves on liquid film surface with gas phase flow. The flow speed of gas phase at the time of beginning of flooding increases with the reduction of amount of liquid flow and the increase of tube diameter. The flooding flow speed is reduced with the increase of tube length. The larger maximum film thickness at the time of no gas phase flow causes flooding at low gas phase flow speed. (Kato, T.)

  6. 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.

  7. Flood discharge measurement of a mountain river – Nanshih River in Taiwan

    Directory of Open Access Journals (Sweden)

    Y.-C. Chen

    2013-05-01

    Full Text Available This study proposes a more efficient method of flood discharge measurement in mountain rivers that accounts for personal safety, accuracy, and reliability. Because it is based on the relationships between mean and maximum velocities and between cross-sectional area and gauge height, the proposed method utilizes a flood discharge measurement system composed of an acoustic Doppler profiler and crane system to measure velocity distributions, cross-sectional area, and water depths. The flood discharge measurement system can be used to accurately and quickly measure flood data that is difficult to be collected by the conventional instruments. The measured data is then used to calibrate the parameters of the proposed method for estimating mean velocity and cross-sectional area. Then these observed discharge and gauge height can be used to establish the water stage–discharge rating curve. Therefor continuous and real-time estimations of flood discharge of a mountain river can become possible. The measurement method and system is applied to the Nanshih River at the Lansheng Bridge. Once the method is established, flood discharge of the Nanshih River could be efficiently estimated using maximum velocity and the water stage. Results of measured and estimated discharges of the Nanshih River at the Lansheng Bridge differed only slightly from each other, demonstrating the efficiency and accuracy of the proposed method.

  8. Maximum entropy principal for transportation

    International Nuclear Information System (INIS)

    Bilich, F.; Da Silva, R.

    2008-01-01

    In this work we deal with modeling of the transportation phenomenon for use in the transportation planning process and policy-impact studies. The model developed is based on the dependence concept, i.e., the notion that the probability of a trip starting at origin i is dependent on the probability of a trip ending at destination j given that the factors (such as travel time, cost, etc.) which affect travel between origin i and destination j assume some specific values. The derivation of the solution of the model employs the maximum entropy principle combining a priori multinomial distribution with a trip utility concept. This model is utilized to forecast trip distributions under a variety of policy changes and scenarios. The dependence coefficients are obtained from a regression equation where the functional form is derived based on conditional probability and perception of factors from experimental psychology. The dependence coefficients encode all the information that was previously encoded in the form of constraints. In addition, the dependence coefficients encode information that cannot be expressed in the form of constraints for practical reasons, namely, computational tractability. The equivalence between the standard formulation (i.e., objective function with constraints) and the dependence formulation (i.e., without constraints) is demonstrated. The parameters of the dependence-based trip-distribution model are estimated, and the model is also validated using commercial air travel data in the U.S. In addition, policy impact analyses (such as allowance of supersonic flights inside the U.S. and user surcharge at noise-impacted airports) on air travel are performed.

  9. Collecting data for quantitative research on pluvial flooding

    NARCIS (Netherlands)

    Spekkers, M.H.; Ten Veldhuis, J.A.E.; Clemens, F.H.L.R.

    2011-01-01

    Urban pluvial flood management requires detailed spatial and temporal information on flood characteristics and damaging consequences. There is lack of quantitative field data on pluvial flooding resulting in large uncertainties in urban flood model calculations and ensuing decisions for investments

  10. Keurbooms Estuary floods and sedimentation

    Directory of Open Access Journals (Sweden)

    Eckart H. Schumann

    2015-11-01

    Full Text Available The Keurbooms Estuary at Plettenberg Bay lies on a wave-dominated, microtidal coast. It has a dune-topped sandy barrier, or barrier dune, almost 4 km long, with a narrow back-barrier lagoon connected to its source rivers, the Keurbooms and Bitou. The estuary exits to the sea through this barrier dune, and it is the geomorphology and mouth position in relation to floods, which is the subject of this paper. Measurements of rainfall, water level, waves and high- and low-tide water lines were used to analyse the mouth variability over the years 2006–2012. Two major floods occurred during this time, with the first in November 2007 eroding away more than 500 000 m3 of sediment. The new mouth was established at the Lookout Rocks limit – the first time since 1915. The second flood occurred in July 2012 and opened up a new mouth about 1 km to the north-east; high waves also affected the position of the breach. The mouth has a tendency to migrate southwards against the longshore drift, but at any stage this movement can be augmented or reversed. The effectiveness of floods in breaching a new mouth through the barrier dune depends on the flood size and the nature of the exit channel in the back-barrier lagoon. Other factors such as ocean waves, sea level, vegetative state of the dune and duration of the flood are also important and can determine where the breach occurs, and if the new mouth will dominate the old mouth.

  11. Flood risk governance arrangements in Europe

    Science.gov (United States)

    Matczak, P.; Lewandowski, J.; Choryński, A.; Szwed, M.; Kundzewicz, Z. W.

    2015-06-01

    The STAR-FLOOD (Strengthening and Redesigning European Flood Risk Practices Towards Appropriate and Resilient Flood Risk Governance Arrangements) project, funded by the European Commission, investigates strategies for dealing with flood risk in six European countries: Belgium, the UK, France, the Netherlands, Poland and Sweden and in 18 vulnerable urban regions in these countries. The project aims to describe, analyse, explain, and evaluate the main similarities and differences between the selected EU Member States in terms of development and performance of flood risk governance arrangements. It also discusses the scientific and societal importance of these similarities and differences. Attention is paid to identification and characterization of shifts in flood risk governance arrangements and in flood risk management strategies and to determination of triggering factors and restraining factors. An assessment of a change of resilience and appropriateness (legitimacy, effectiveness, efficiency) of flood risk governance arrangements in Poland is presented and comparison with other European countries is offered.

  12. Rhine Cities - Urban Flood Integration (UFI)

    NARCIS (Netherlands)

    Redeker, C.

    2013-01-01

    While agglomerations along the Rhine are confronted with the uncertainties of an increasing flood risk due to climate change, different programs are claiming urban river front sites. Simultaneously, urban development, flood management, as well as navigation and environmental protection are

  13. Flood Insurance Rate Map, Scott County, 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...

  14. DIGITAL FLOOD INSURANCE RATE MAP DATABASE,

    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. Sept 2013 NFHL Flood Hazard Boundaries

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The National Flood Hazard Layer (NFHL) data incorporates all Digital Flood Insurance Rate Map(DFIRM) databases published by FEMA, and any Letters Of Map Revision...

  16. Seismic risks posed by mine flooding

    CSIR Research Space (South Africa)

    Goldbach, OD

    2009-09-01

    Full Text Available are allowed to flood. Such flooding-induced seismicity can have significant environmental, social and economic consequences, and may endanger neighbouring mines and surface communities. While fluid-induced seismicity has been observed in other settings (e...

  17. Flood risk governance arrangements in Europe

    Directory of Open Access Journals (Sweden)

    P. Matczak

    2015-06-01

    Full Text Available The STAR-FLOOD (Strengthening and Redesigning European Flood Risk Practices Towards Appropriate and Resilient Flood Risk Governance Arrangements project, funded by the European Commission, investigates strategies for dealing with flood risk in six European countries: Belgium, the UK, France, the Netherlands, Poland and Sweden and in 18 vulnerable urban regions in these countries. The project aims to describe, analyse, explain, and evaluate the main similarities and differences between the selected EU Member States in terms of development and performance of flood risk governance arrangements. It also discusses the scientific and societal importance of these similarities and differences. Attention is paid to identification and characterization of shifts in flood risk governance arrangements and in flood risk management strategies and to determination of triggering factors and restraining factors. An assessment of a change of resilience and appropriateness (legitimacy, effectiveness, efficiency of flood risk governance arrangements in Poland is presented and comparison with other European countries is offered.

  18. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, , 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;...

  19. The dynamic capacity calculation method and the flood control ability of the Three Gorges Reservoir

    Science.gov (United States)

    Zhang, Shanghong; Jing, Zhu; Yi, Yujun; Wu, Yu; Zhao, Yong

    2017-12-01

    To evaluate the flood control ability of a river-type reservoir, an accurate simulation method for the flood storage, discharge process, and dynamic capacity of the reservoir is important. As the world's largest reservoir, the storage capacity and flood control capacity of the Three Gorges Reservoir (TGR) has attracted widespread interest and academic debate for nearly 20 years. In this study, a model for calculating the dynamic capacity of a river-type reservoir is established based on data from 394 river cross sections and 2.5-m resolution digital elevation model (DEM) data of the TGR area. The storage capacity and flood control capacity of the TGR were analysed based on the scheduling procedures of a normal impoundment period. The results show that the static capacity of the TGR is 43.43 billion m3, the dynamic flood control capacity is 22.45 billion m3, and the maximum floodwater flow regulated by the dynamic capacity at Zhicheng is no more than 67,700 m3/s. This study supply new simulation method and up-to-date high-precision data to discuss the 20 years debate, and the results reveal the TGR design is conservative for flood control according to the Preliminary Design Report of the Three Gorges Project. The dynamic capacity calculation method used here can provide a reference for flood regulation of large river-type reservoirs.

  20. Flood Risk Zoning by Using 2D Hydrodynamic Modeling: A Case Study in Jinan City

    Directory of Open Access Journals (Sweden)

    Tao Cheng

    2017-01-01

    Full Text Available Climate change and rapid urbanization have aggravated the rainstorm flood in Jinan City during the past decades. Jinan City is higher in the south and lower in the north with a steep slope inclined from the south to the north. This results in high-velocity overland flow and deep waterlogging, which poses a tremendous threat to pedestrians and vehicles. Therefore, it is vital to investigate the rainstorm flood and further perform flood risk zoning. This study is carried out in the “Sponge City Construction” pilot area of Jinan City, where the InfoWorks ICM 2D hydrodynamic model is utilized for simulating historical and designed rainfall events. The model is validated with observations, and the causes for errors are analyzed. The simulated water depth and flow velocity are recorded for flood risk zoning. The result shows that the InfoWorks ICM 2D model performed well. The flood risk zoning result shows that rainfalls with larger recurrence intervals generate larger areas of moderate to extreme risk. Meanwhile, the zoning results for the two historical rainfalls show that flood with a higher maximum hourly rainfall intensity is more serious. This study will provide scientific support for the flood control and disaster reduction in Jinan City.

  1. Water NOT wanted - Coastal Floods and Flooding Protection in Denmark

    DEFF Research Database (Denmark)

    Sørensen, Carlo Sass

    2016-01-01

    vulnerability towards coastal flooding, the country has experienced severe storm surges throughout history, and hitherto safe areas will become increasingly at risk this century as the climate changes. Historically a seafarers’ nation, Denmark has always been connected with the sea. From medieval time ports...

  2. Field note from Pakistan floods: Preventing future flood disasters

    Directory of Open Access Journals (Sweden)

    Marcus Oxley

    2011-04-01

    Full Text Available Unusually heavy monsoon rains in Northern Pakistan have caused disproportionate levels of extreme flooding and unprecedented flood losses across the entire Indus River basin. Extensive land use changes and environmental degradation in the uplands and lowlands of the river basin together with the construction of a “built environment” out of balance with the functioning, capacities, scale and limits of the local ecosystems have exposed millions of people to an increased risk of extreme #ooding. The catastrophic nature of the August #ooding provides a unique opportunity to fundamentally change Pakistan’s current socio-economic development path by incorporating disaster risk reduction and climate change measures into the post-disaster recovery process to rebuild a safer, more resilient nation. In January 2005 one hundred and sixty-eight nations adopted the Hyogo Framework for Action (HFA2005-2015 to bring about a “substantial reduction in disaster losses” by 2015. Despite this global initiative a series of major disasters, including the recent flooding in Pakistan, all indicate that we are not on track to achieve the substantial reduction of disaster losses. The following fieldnote considers what can be done to accelerate progress towards implementation of the Hyogo Framework, drawing on insights and lessons learnt from the August flooding to understand how Pakistan and neighbouring countries can prevent a repeat of such catastrophic disasters in future years.

  3. Integrating Entropy-Based Naïve Bayes and GIS for Spatial Evaluation of Flood Hazard.

    Science.gov (United States)

    Liu, Rui; Chen, Yun; Wu, Jianping; Gao, Lei; Barrett, Damian; Xu, Tingbao; Li, Xiaojuan; Li, Linyi; Huang, Chang; Yu, Jia

    2017-04-01

    Regional flood risk caused by intensive rainfall under extreme climate conditions has increasingly attracted global attention. Mapping and evaluation of flood hazard are vital parts in flood risk assessment. This study develops an integrated framework for estimating spatial likelihood of flood hazard by coupling weighted naïve Bayes (WNB), geographic information system, and remote sensing. The north part of Fitzroy River Basin in Queensland, Australia, was selected as a case study site. The environmental indices, including extreme rainfall, evapotranspiration, net-water index, soil water retention, elevation, slope, drainage proximity, and density, were generated from spatial data representing climate, soil, vegetation, hydrology, and topography. These indices were weighted using the statistics-based entropy method. The weighted indices were input into the WNB-based model to delineate a regional flood risk map that indicates the likelihood of flood occurrence. The resultant map was validated by the maximum inundation extent extracted from moderate resolution imaging spectroradiometer (MODIS) imagery. The evaluation results, including mapping and evaluation of the distribution of flood hazard, are helpful in guiding flood inundation disaster responses for the region. The novel approach presented consists of weighted grid data, image-based sampling and validation, cell-by-cell probability inferring and spatial mapping. It is superior to an existing spatial naive Bayes (NB) method for regional flood hazard assessment. It can also be extended to other likelihood-related environmental hazard studies. © 2016 Society for Risk Analysis.

  4. Effect of off-season flooding on growth, photosynthesis, carbohydrate partitioning, and nutrient uptake in Distylium chinense.

    Directory of Open Access Journals (Sweden)

    Zebin Liu

    Full Text Available Distylium chinense is an evergreen shrub used for the vegetation recovery of floodplain and riparian areas in Three Gorges Reservoir Region. To clarify the morphological and physiological responses and tolerance of Distylium chinense to off-season flooding, a simulation flooding experiment was conducted during autumn and winter. Results indicated that the survival rate of seedlings was 100%, and that plant height and stem diameter were not significantly affected by flooding. Adventitious roots and hypertrophic lenticels were observed in flooded seedlings after 30 days of flooding. Flooding significantly reduced the plant biomass of roots, net photosynthetic rate (Pn, stomatal conductance (gs, transpiration rate (Tr, maximum photochemical efficiency (Fv/Fm, photochemical quenching (qP, and electron transport rate (ETR in leaves, and also affected the allocation and transport of carbohydrate and nutrients. However, D. chinense was able to maintain stable levels of Pn, Fv/Fm, qP, ETR, and nutrient content (N and P in leaves and to store a certain amount of carbohydrate in roots over prolonged durations of flooding. Based on these results, we conclude that there is a high flooding tolerance in D. chinense, and the high survival rate of D. chinense may be attributable to a combination of morphological and physiological responses to flooding.

  5. Effect of off-season flooding on growth, photosynthesis, carbohydrate partitioning, and nutrient uptake in Distylium chinense.

    Science.gov (United States)

    Liu, Zebin; Cheng, Ruimei; Xiao, Wenfa; Guo, Quanshui; Wang, Na

    2014-01-01

    Distylium chinense is an evergreen shrub used for the vegetation recovery of floodplain and riparian areas in Three Gorges Reservoir Region. To clarify the morphological and physiological responses and tolerance of Distylium chinense to off-season flooding, a simulation flooding experiment was conducted during autumn and winter. Results indicated that the survival rate of seedlings was 100%, and that plant height and stem diameter were not significantly affected by flooding. Adventitious roots and hypertrophic lenticels were observed in flooded seedlings after 30 days of flooding. Flooding significantly reduced the plant biomass of roots, net photosynthetic rate (Pn), stomatal conductance (gs), transpiration rate (Tr), maximum photochemical efficiency (Fv/Fm), photochemical quenching (qP), and electron transport rate (ETR) in leaves, and also affected the allocation and transport of carbohydrate and nutrients. However, D. chinense was able to maintain stable levels of Pn, Fv/Fm, qP, ETR, and nutrient content (N and P) in leaves and to store a certain amount of carbohydrate in roots over prolonged durations of flooding. Based on these results, we conclude that there is a high flooding tolerance in D. chinense, and the high survival rate of D. chinense may be attributable to a combination of morphological and physiological responses to flooding.

  6. Last Glacial Maximum Salinity Reconstruction

    Science.gov (United States)

    Homola, K.; Spivack, A. J.

    2016-12-01

    It has been previously demonstrated that salinity can be reconstructed from sediment porewater. The goal of our study is to reconstruct high precision salinity during the Last Glacial Maximum (LGM). Salinity is usually determined at high precision via conductivity, which requires a larger volume of water than can be extracted from a sediment core, or via chloride titration, which yields lower than ideal precision. It has been demonstrated for water column samples that high precision density measurements can be used to determine salinity at the precision of a conductivity measurement using the equation of state of seawater. However, water column seawater has a relatively constant composition, in contrast to porewater, where variations from standard seawater composition occur. These deviations, which affect the equation of state, must be corrected for through precise measurements of each ion's concentration and knowledge of apparent partial molar density in seawater. We have developed a density-based method for determining porewater salinity that requires only 5 mL of sample, achieving density precisions of 10-6 g/mL. We have applied this method to porewater samples extracted from long cores collected along a N-S transect across the western North Atlantic (R/V Knorr cruise KN223). Density was determined to a precision of 2.3x10-6 g/mL, which translates to salinity uncertainty of 0.002 gms/kg if the effect of differences in composition is well constrained. Concentrations of anions (Cl-, and SO4-2) and cations (Na+, Mg+, Ca+2, and K+) were measured. To correct salinities at the precision required to unravel LGM Meridional Overturning Circulation, our ion precisions must be better than 0.1% for SO4-/Cl- and Mg+/Na+, and 0.4% for Ca+/Na+, and K+/Na+. Alkalinity, pH and Dissolved Inorganic Carbon of the porewater were determined to precisions better than 4% when ratioed to Cl-, and used to calculate HCO3-, and CO3-2. Apparent partial molar densities in seawater were

  7. Maximum Parsimony on Phylogenetic networks

    Science.gov (United States)

    2012-01-01

    Background Phylogenetic networks are generalizations of phylogenetic trees, that are used to model evolutionary events in various contexts. Several different methods and criteria have been introduced for reconstructing phylogenetic trees. Maximum Parsimony is a character-based approach that infers a phylogenetic tree by minimizing the total number of evolutionary steps required to explain a given set of data assigned on the leaves. Exact solutions for optimizing parsimony scores on phylogenetic trees have been introduced in the past. Results In this paper, we define the parsimony score on networks as the sum of the substitution costs along all the edges of the network; and show that certain well-known algorithms that calculate the optimum parsimony score on trees, such as Sankoff and Fitch algorithms extend naturally for networks, barring conflicting assignments at the reticulate vertices. We provide heuristics for finding the optimum parsimony scores on networks. Our algorithms can be applied for any cost matrix that may contain unequal substitution costs of transforming between different characters along different edges of the network. We analyzed this for experimental data on 10 leaves or fewer with at most 2 reticulations and found that for almost all networks, the bounds returned by the heuristics matched with the exhaustively determined optimum parsimony scores. Conclusion The parsimony score we define here does not directly reflect the cost of the best tree in the network that displays the evolution of the character. However, when searching for the most parsimonious network that describes a collection of characters, it becomes necessary to add additional cost considerations to prefer simpler structures, such as trees over networks. The parsimony score on a network that we describe here takes into account the substitution costs along the additional edges incident on each reticulate vertex, in addition to the substitution costs along the other edges which are

  8. Analysis of flood-magnitude and flood-frequency data for streamflow-gaging stations in the Delaware and North Branch Susquehanna River Basins in Pennsylvania

    Science.gov (United States)

    Roland, Mark A.; Stuckey, Marla H.

    2007-01-01

    The Delaware and North Branch Susquehanna River Basins in Pennsylvania experienced severe flooding as a result of intense rainfall during June 2006. The height of the flood waters on the rivers and tributaries approached or exceeded the peak of record at many locations. Updated flood-magnitude and flood-frequency data for streamflow-gaging stations on tributaries in the Delaware and North Branch Susquehanna River Basins were analyzed using data through the 2006 water year to determine if there were any major differences in the flood-discharge data. Flood frequencies for return intervals of 2, 5, 10, 50, 100, and 500 years (Q2, Q5, Q10, Q50, Q100, and Q500) were determined from annual maximum series (AMS) data from continuous-record gaging stations (stations) and were compared to flood discharges obtained from previously published Flood Insurance Studies (FIS) and to flood frequencies using partial-duration series (PDS) data. A Wilcoxon signed-rank test was performed to determine any statistically significant differences between flood frequencies computed from updated AMS station data and those obtained from FIS. Percentage differences between flood frequencies computed from updated AMS station data and those obtained from FIS also were determined for the 10, 50, 100, and 500 return intervals. A Mann-Kendall trend test was performed to determine statistically significant trends in the updated AMS peak-flow data for the period of record at the 41 stations. In addition to AMS station data, PDS data were used to determine flood-frequency discharges. The AMS and PDS flood-frequency data were compared to determine any differences between the two data sets. An analysis also was performed on AMS-derived flood frequencies for four stations to evaluate the possible effects of flood-control reservoirs on peak flows. Additionally, flood frequencies for three stations were evaluated to determine possible effects of urbanization on peak flows. The results of the Wilcoxon signed

  9. Flood Label for buildings : a tool for more flood-resilient cities

    NARCIS (Netherlands)

    Hartmann, T.; Scheibel, Marc

    2016-01-01

    River floods are among the most expensive natural disasters in Europe. Traditional flood protection methods are not sufficient anymore. It is widely acknowledged in the scholarly debate and in practice of flood risk management that traditional flood protection measures such as dikes need to be

  10. Effectiveness of flood damage mitigation measures: Empirical evidence from French flood disasters

    NARCIS (Netherlands)

    Poussin, J.K.; Botzen, W.J.W.; Aerts, J.C.J.H.

    2015-01-01

    Recent destructive flood events and projected increases in flood risks as a result of climate change in many regions around the world demonstrate the importance of improving flood risk management. Flood-proofing of buildings is often advocated as an effective strategy for limiting damage caused by

  11. Flooding in imagination vs flooding in vivo: A comparison with agoraphobics

    NARCIS (Netherlands)

    Emmelkamp, Paul M.G.; Wessels, Hemmy

    In this investigation of agoraphobic patients, 3 different flooding procedures were compared: (1) prolonged exposure in vivo, (2) flooding in the imagination by a ‘live’ therapist and (3) a combination of flooding in the imagination and flooding in vivo. After an intermediate-test all clients were

  12. Why are decisions in flood disaster management so poorly supported by information from flood models?

    NARCIS (Netherlands)

    Leskens, Anne; Brugnach, Marcela Fabiana; Hoekstra, Arjen Ysbert; Schuurmans, W.

    2014-01-01

    Flood simulation models can provide practitioners of Flood Disaster Management with sophisticated estimates of floods. Despite the advantages that flood simulation modeling may provide, experiences have proven that these models are of limited use. Until now, this problem has mainly been investigated

  13. Economic optimisation of flood risk management projects

    NARCIS (Netherlands)

    Tsimopoulou, V.

    2015-01-01

    The Netherlands has developed a flood risk management policy based on an economic rationale. After the flood disaster of 1953, when a large area of the south-western part of the country was flooded and more than 1800 people lost their lives, the so-called Delta Committee was installed, whose main

  14. Exploring logistics aspects of flood emergency measures

    NARCIS (Netherlands)

    de Leeuw, S.L.J.M.; Vis, I.F.A.; Jonkman, S.N.

    2012-01-01

    Floods are often preceded by warnings such as heavy rain that may make preparatory activities possible in order to prevent flooding from actually happening. However, flood emergency preparedness lacks insight in logistical aspects. This paper develops a framework of logistical aspects of emergency

  15. Exploring Logistics Aspects of Flood Emergency Measures

    NARCIS (Netherlands)

    de Leeuw, Sander; Vis, Iris F. A.; Jonkman, Sebastiaan N.

    Floods are often preceded by warnings such as heavy rain that may make preparatory activities possible in order to prevent flooding from actually happening. However, flood emergency preparedness lacks insight in logistical aspects. This paper develops a framework of logistical aspects of emergency

  16. Application of RUNTA code in flood analyses

    International Nuclear Information System (INIS)

    Perez Martin, F.; Benitez Fonzalez, F.

    1994-01-01

    Flood probability analyses carried out to date indicate the need to evaluate a large number of flood scenarios. This necessity is due to a variety of reasons, the most important of which include: - Large number of potential flood sources - Wide variety of characteristics of flood sources - Large possibility of flood-affected areas becoming inter linked, depending on the location of the potential flood sources - Diversity of flood flows from one flood source, depending on the size of the rupture and mode of operation - Isolation times applicable - Uncertainties in respect of the structural resistance of doors, penetration seals and floors - Applicable degrees of obstruction of floor drainage system Consequently, a tool which carries out the large number of calculations usually required in flood analyses, with speed and flexibility, is considered necessary. The RUNTA Code enables the range of possible scenarios to be calculated numerically, in accordance with all those parameters which, as a result of previous flood analyses, it is necessary to take into account in order to cover all the possible floods associated with each flood area

  17. Flood Progression Modelling and Impact Analysis

    DEFF Research Database (Denmark)

    Mioc, Darka; Anton, François; Nickerson, B.

    People living in the lower valley of the St. John River, New Brunswick, Canada, frequently experience flooding when the river overflows its banks during spring ice melt and rain. To better prepare the population of New Brunswick for extreme flooding, we developed a new flood prediction model...

  18. Interconnected ponds operation for flood hazard distribution

    Science.gov (United States)

    Putra, S. S.; Ridwan, B. W.

    2016-05-01

    The climatic anomaly, which comes with extreme rainfall, will increase the flood hazard in an area within a short period of time. The river capacity in discharging the flood is not continuous along the river stretch and sensitive to the flood peak. This paper contains the alternatives on how to locate the flood retention pond that are physically feasible to reduce the flood peak. The flood ponds were designed based on flood curve number criteria (TR-55, USDA) with the aim of rapid flood peak capturing and gradual flood retuning back to the river. As a case study, the hydrologic condition of upper Ciliwung river basin with several presumed flood pond locations was conceptually designed. A fundamental tank model that reproducing the operation of interconnected ponds was elaborated to achieve the designed flood discharge that will flows to the downstream area. The flood hazard distribution status, as the model performance criteria, will be computed within Ciliwung river reach in Manggarai Sluice Gate spot. The predicted hazard reduction with the operation of the interconnected retention area result had been bench marked with the normal flow condition.

  19. The European Flood Risk Directive and Ethics

    NARCIS (Netherlands)

    Mostert, E.; Doorn, N.

    2012-01-01

    The European Flood risk directive (2007/60/EC) requires EU Member States to review their system of flood risk management. In doing so, they will have to face ethical issues inherent in flood risk management. This paper discusses three such issues, using examples from the Netherlands. These issues

  20. 33 CFR 385.37 - Flood protection.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Flood protection. 385.37 Section... DEFENSE PROGRAMMATIC REGULATIONS FOR THE COMPREHENSIVE EVERGLADES RESTORATION PLAN Ensuring Protection of... Flood protection. (a) General. In accordance with section 601 of WRDA 2000, flood protection, consistent...

  1. 46 CFR 28.580 - Unintentional flooding.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Unintentional flooding. 28.580 Section 28.580 Shipping... INDUSTRY VESSELS Stability § 28.580 Unintentional flooding. (a) Applicability. Except for an open boat that... survive the assumed damage and unintentional flooding described in paragraphs (d) and (e) of this section...

  2. 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 ...

  3. 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.

  4. Continental and global scale flood forecasting systems

    NARCIS (Netherlands)

    Emerton, Rebecca E.; Stephens, Elisabeth M.; Pappenberger, Florian; Pagano, Thomas P.; Weerts, A.H.; Wood, A.; Salamon, Peter; Brown, James D.; Hjerdt, Niclas; Donnelly, Chantal; Baugh, Calum A.; Cloke, Hannah L.

    2016-01-01

    Floods are the most frequent of natural disasters, affecting millions of people across the globe every year. The anticipation and forecasting of floods at the global scale is crucial to preparing for severe events and providing early awareness where local flood models and warning services may not

  5. Determination of minimum flood flow for regeneration of floodplain forest from inundated forest width-stage curve

    Directory of Open Access Journals (Sweden)

    Song-hao Shang

    2010-09-01

    Full Text Available Floods are essential for the regeneration and growth of floodplain forests in arid and semiarid regions. However, river flows, and especially flood flows, have decreased greatly with the increase of water diversion from rivers and/or reservoir regulation, resulting in severe deterioration of floodplain ecosystems. Estimation of the flood stage that will inundate the floodplain forest is necessary for the forest's restoration or protection. To balance water use for economic purposes and floodplain forest protection, the inundated forest width method is proposed for estimating the minimum flood stage for floodplain forests from the inundated forest width-stage curve. The minimum flood stage is defined as the breakpoint of the inundated forest width-stage curve, and is determined directly or analytically from the curve. For the analytical approach, the problem under consideration is described by a multi-objective optimization model, which can be solved by the ideal point method. Then, the flood flow at the minimum flood stage (minimum flood flow, which is useful for flow regulation, can be calculated from the stage-discharge curve. In order to protect the forest in a river floodplain in a semiarid area in Xinjiang subject to reservoir regulation upstream, the proposed method was used to determine the minimum flood stage and flow for the forest. Field survey of hydrology, topography, and forest distribution was carried out at typical cross sections in the floodplain. Based on the survey results, minimum flood flows for six typical cross sections were estimated to be between 306 m3/s and 393 m3/s. Their maximum, 393 m3/s, was considered the minimum flood flow for the study river reach. This provides an appropriate flood flow for the protection of floodplain forest and can be used in the regulation of the upstream reservoir.

  6. Flood Risk Management in the People’s Republic of China: Learning to Live with Flood Risk

    OpenAIRE

    Asian Development Bank (ADB); Asian Development Bank (ADB); Asian Development Bank (ADB); Asian Development Bank (ADB)

    2012-01-01

    This publication presents a shift in the People’s Republic of China from flood control depending on structural measures to integrated flood management using both structural and non-structural measures. The core of the new concept of integrated flood management is flood risk management. Flood risk management is based on an analysis of flood hazard, exposure to flood hazard, and vulnerability of people and property to danger. It is recommended that people learn to live with flood risks, gaining...

  7. A large-scale simulation of climate change effects on flood regime - A case study for the Alabama-Coosa-Tallapoosa River Basin

    Science.gov (United States)

    Dullo, T. T.; Gangrade, S.; Marshall, R.; Islam, S. R.; Ghafoor, S. K.; Kao, S. C.; Kalyanapu, A. J.

    2017-12-01

    The damage and cost of flooding are continuously increasing due to climate change and variability, which compels the development and advance of global flood hazard models. However, due to computational expensiveness, evaluation of large-scale and high-resolution flood regime remains a challenge. The objective of this research is to use a coupled modeling framework that consists of a dynamically downscaled suite of eleven Coupled Model Intercomparison Project Phase 5 (CMIP5) climate models, a distributed hydrologic model called DHSVM, and a computational-efficient 2-dimensional hydraulic model called Flood2D-GPU to study the impacts of climate change on flood regime in the Alabama-Coosa-Tallapoosa (ACT) River Basin. Downscaled meteorologic forcings for 40 years in the historical period (1966-2005) and 40 years in the future period (2011-2050) were used as inputs to drive the calibrated DHSVM to generate annual maximum flood hydrographs. These flood hydrographs along with 30-m resolution digital elevation and estimated surface roughness were then used by Flood2D-GPU to estimate high-resolution flood depth, velocities, duration, and regime. Preliminary results for the Conasauga river basin (an upper subbasin within ACT) indicate that seven of the eleven climate projections show an average increase of 25 km2 in flooded area (between historic and future projections). Future work will focus on illustrating the effects of climate change on flood duration and area for the entire ACT basin.

  8. Combined fluvial and pluvial urban flood hazard analysis: concept development and application to Can Tho city, Mekong Delta, Vietnam

    Science.gov (United States)

    Apel, Heiko; Martínez Trepat, Oriol; Nghia Hung, Nguyen; Thi Chinh, Do; Merz, Bruno; Viet Dung, Nguyen

    2016-04-01

    coincidence into account. All hazards - fluvial, pluvial and combined - were accompanied by an uncertainty estimation taking into account the natural variability of the flood events. This resulted in probabilistic flood hazard maps showing the maximum inundation depths for a selected set of probabilities of occurrence, with maps showing the expectation (median) and the uncertainty by percentile maps. The results are critically discussed and their usage in flood risk management are outlined.

  9. Neural networks-based operational prototype for flash flood forecasting: application to Liane flash floods (France

    Directory of Open Access Journals (Sweden)

    Bertin Dominique

    2016-01-01

    Full Text Available The Liane River is a small costal river, famous for its floods, which can affect the city of Boulogne-sur-Mer. Due to the complexity of land cover and hydrologic processes, a black-box non-linear modelling was chosen using neural networks. The multilayer perceptron model, known for its property of universal approximation is thus chosen. Four models were designed, each one for one forecasting horizon using rainfall forecasts: 24h, 12h, 6h, 3h. The desired output of the model is original: it represents the maximal value of the water level respectively 24h, 12h, 6h, 3h ahead. Working with best forecasts of rain (the observed ones during the event in the past, on the major flood of the database in test set, the model provides excellent forecasts. Nash criteria calculated for the four lead times are 0.98 (3h, 0.97 (6h, 0.91 (12h, 0.89 (24h. Designed models were thus estimated as efficient enough to be implemented in a specific tool devoted to real time operational use. The software tool is described hereafter: designed in Java, it presents a friendly interface allowing applying various scenarios of future rainfalls, and a graphical visualization of the predicted maximum water levels and their associated real time observed values.

  10. Analyzing temporal changes in maximum runoff volume series of the Danube River

    International Nuclear Information System (INIS)

    Halmova, Dana; Pekarova, Pavla; Onderka, Milan; Pekar, Jan

    2008-01-01

    Several hypotheses claim that more extremes in climatic and hydrologic phenomena are anticipated. In order to verify such hypotheses it is inevitable to examine the past periods by thoroughly analyzing historical data. In the present study, the annual maximum runoff volumes with t-day durations were calculated for a 130-year series of mean daily discharge of Danube River at Bratislava gauge (Slovakia). Statistical methods were used to clarify how the maximum runoff volumes of the Danube River changed over two historical periods (1876-1940 and 1941-2005). The conclusion is that the runoff volume regime during floods has not changed significantly during the last 130 years.

  11. Modelling dynamic roughness during floods

    NARCIS (Netherlands)

    Paarlberg, Andries; Dohmen-Janssen, Catarine M.; Hulscher, Suzanne J.M.H.; Termes, A.P.P.

    2007-01-01

    In this paper, we present a dynamic roughness model to predict water levels during floods. Hysteresis effects of dune development are explicitly included. It is shown that differences between the new dynamic roughness model, and models where the roughness coefficient is calibrated, are most

  12. A Fair Approach to Flooding

    NARCIS (Netherlands)

    Doorn, N.

    2017-01-01

    Floods can be some of the most unexpected and devastating natural phenomena. Reducing their risks everywhere is near impossible, whether due to financial reasons or more physical obstacles. Dr Neelke Doorn at Delft University of Technology is working to improve policies related to water, with the

  13. Feedback on flood risk management

    Science.gov (United States)

    Moreau, K.; Roumagnac, A.

    2009-09-01

    For several years, as floods were increasing in South of France, local communities felt deprive to assume their mission of protection and information of citizens, and were looking for assistance in flood management. In term of flood disaster, the fact is that physical protection is necessary but inevitably limited. Tools and structures of assistance to anticipation remain slightly developed. To manage repeated crisis, local authorities need to be able to base their policy against flood on prevention, warnings, post-crisis analysis and feedback from former experience. In this objective, after 3 years of test and improvement since 2003, the initiative Predict-Services was developped in South of France: it aims at helping communities and companies to face repeated flood crisis. The principle is to prepare emergency plans, to organize crisis management and reduce risks; to help and assist communities and companies during crisis to activate and adapt their emergency plans with enough of anticipation; and to analyse floods effects and improve emergency plans afterwards. In order to reduce risks, and to keep the benefits of such an initiative, local communities and companies have to maintain the awareness of risk of the citizens and employees. They also have to maintain their safety plans to keep them constantly operational. This is a part of the message relayed. Companies, Local communities, local government authorities and basin stakeholders are the decision makers. Companies and local communities have to involve themselves in the elaboration of safety plans. They are also completely involved in their activation that is their own responsability. This applies to other local government authorities, like districts one's and basin stakeholders, which participle in the financing community safety plans and adminitrative district which are responsible of the transmission of meteorological alert and of rescue actions. In the crossing of the géo-information stemming from the

  14. Two-dimensional maximum entropy image restoration

    International Nuclear Information System (INIS)

    Brolley, J.E.; Lazarus, R.B.; Suydam, B.R.; Trussell, H.J.

    1977-07-01

    An optical check problem was constructed to test P LOG P maximum entropy restoration of an extremely distorted image. Useful recovery of the original image was obtained. Comparison with maximum a posteriori restoration is made. 7 figures

  15. Has dyke development in the Vietnamese Mekong Delta shifted flood hazard downstream?

    Science.gov (United States)

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

    2017-08-01

    In the Vietnamese part of the Mekong Delta (VMD) the areas with three rice crops per year have been expanded rapidly during the last 15 years. Paddy-rice cultivation during the flood season has been made possible by implementing high-dyke flood defenses and flood control structures. However, there are widespread claims that the high-dyke system has increased water levels in downstream areas. Our study aims at resolving this issue by attributing observed changes in flood characteristics to high-dyke construction and other possible causes. Maximum water levels and duration above the flood alarm level are analysed for gradual trends and step changes at different discharge gauges. Strong and robust increasing trends of peak water levels and duration downstream of the high-dyke areas are found with a step change in 2000/2001, i.e. immediately after the disastrous flood which initiated the high-dyke development. These changes are in contrast to the negative trends detected at stations upstream of the high-dyke areas. This spatially different behaviour of changes in flood characteristics seems to support the public claims. To separate the impact of the high-dyke development from the impact of the other drivers - i.e. changes in the flood hydrograph entering the Mekong Delta, and changes in the tidal dynamics - hydraulic model simulations of the two recent large flood events in 2000 and 2011 are performed. The hydraulic model is run for a set of scenarios whereas the different drivers are interchanged. The simulations reveal that for the central VMD an increase of 9-13 cm in flood peak and 15 days in duration can be attributed to high-dyke development. However, for this area the tidal dynamics have an even larger effect in the range of 19-32 cm. However, the relative contributions of the three drivers of change vary in space across the delta. In summary, our study confirms the claims that the high-dyke development has raised the flood hazard downstream. However, it is not

  16. Has dyke development in the Vietnamese Mekong Delta shifted flood hazard downstream?

    Directory of Open Access Journals (Sweden)

    N. V. K. Triet

    2017-08-01

    Full Text Available In the Vietnamese part of the Mekong Delta (VMD the areas with three rice crops per year have been expanded rapidly during the last 15 years. Paddy-rice cultivation during the flood season has been made possible by implementing high-dyke flood defenses and flood control structures. However, there are widespread claims that the high-dyke system has increased water levels in downstream areas. Our study aims at resolving this issue by attributing observed changes in flood characteristics to high-dyke construction and other possible causes. Maximum water levels and duration above the flood alarm level are analysed for gradual trends and step changes at different discharge gauges. Strong and robust increasing trends of peak water levels and duration downstream of the high-dyke areas are found with a step change in 2000/2001, i.e. immediately after the disastrous flood which initiated the high-dyke development. These changes are in contrast to the negative trends detected at stations upstream of the high-dyke areas. This spatially different behaviour of changes in flood characteristics seems to support the public claims. To separate the impact of the high-dyke development from the impact of the other drivers – i.e. changes in the flood hydrograph entering the Mekong Delta, and changes in the tidal dynamics – hydraulic model simulations of the two recent large flood events in 2000 and 2011 are performed. The hydraulic model is run for a set of scenarios whereas the different drivers are interchanged. The simulations reveal that for the central VMD an increase of 9–13 cm in flood peak and 15 days in duration can be attributed to high-dyke development. However, for this area the tidal dynamics have an even larger effect in the range of 19–32 cm. However, the relative contributions of the three drivers of change vary in space across the delta. In summary, our study confirms the claims that the high-dyke development has raised the flood

  17. Flood quantile estimation at ungauged sites by Bayesian networks

    Science.gov (United States)

    Mediero, L.; Santillán, D.; Garrote, L.

    2012-04-01

    Estimating flood quantiles at a site for which no observed measurements are available is essential for water resources planning and management. Ungauged sites have no observations about the magnitude of floods, but some site and basin characteristics are known. The most common technique used is the multiple regression analysis, which relates physical and climatic basin characteristic to flood quantiles. Regression equations are fitted from flood frequency data and basin characteristics at gauged sites. Regression equations are a rigid technique that assumes linear relationships between variables and cannot take the measurement errors into account. In addition, the prediction intervals are estimated in a very simplistic way from the variance of the residuals in the estimated model. Bayesian networks are a probabilistic computational structure taken from the field of Artificial Intelligence, which have been widely and successfully applied to many scientific fields like medicine and informatics, but application to the field of hydrology is recent. Bayesian networks infer the joint probability distribution of several related variables from observations through nodes, which represent random variables, and links, which represent causal dependencies between them. A Bayesian network is more flexible than regression equations, as they capture non-linear relationships between variables. In addition, the probabilistic nature of Bayesian networks allows taking the different sources of estimation uncertainty into account, as they give a probability distribution as result. A homogeneous region in the Tagus Basin was selected as case study. A regression equation was fitted taking the basin area, the annual maximum 24-hour rainfall for a given recurrence interval and the mean height as explanatory variables. Flood quantiles at ungauged sites were estimated by Bayesian networks. Bayesian networks need to be learnt from a huge enough data set. As observational data are reduced, a

  18. Modelling Inland Flood Events for Hazard Maps in Taiwan

    Science.gov (United States)

    Ghosh, S.; Nzerem, K.; Sassi, M.; Hilberts, A.; Assteerawatt, A.; Tillmanns, S.; Mathur, P.; Mitas, C.; Rafique, F.

    2015-12-01

    Taiwan experiences significant inland flooding, driven by torrential rainfall from plum rain storms and typhoons during summer and fall. From last 13 to 16 years data, 3,000 buildings were damaged by such floods annually with a loss US$0.41 billion (Water Resources Agency). This long, narrow island nation with mostly hilly/mountainous topography is located at tropical-subtropical zone with annual average typhoon-hit-frequency of 3-4 (Central Weather Bureau) and annual average precipitation of 2502mm (WRA) - 2.5 times of the world's average. Spatial and temporal distributions of countrywide precipitation are uneven, with very high local extreme rainfall intensities. Annual average precipitation is 3000-5000mm in the mountainous regions, 78% of it falls in May-October, and the 1-hour to 3-day maximum rainfall are about 85 to 93% of the world records (WRA). Rivers in Taiwan are short with small upstream areas and high runoff coefficients of watersheds. These rivers have the steepest slopes, the shortest response time with rapid flows, and the largest peak flows as well as specific flood peak discharge (WRA) in the world. RMS has recently developed a countrywide inland flood model for Taiwan, producing hazard return period maps at 1arcsec grid resolution. These can be the basis for evaluating and managing flood risk, its economic impacts, and insured flood losses. The model is initiated with sub-daily historical meteorological forcings and calibrated to daily discharge observations at about 50 river gauges over the period 2003-2013. Simulations of hydrologic processes, via rainfall-runoff and routing models, are subsequently performed based on a 10000 year set of stochastic forcing. The rainfall-runoff model is physically based continuous, semi-distributed model for catchment hydrology. The 1-D wave propagation hydraulic model considers catchment runoff in routing and describes large-scale transport processes along the river. It also accounts for reservoir storage

  19. A coupled weather generator - rainfall-runoff approach on hourly time steps for flood risk analysis

    Science.gov (United States)

    Winter, Benjamin; Schneeberger, Klaus; Dung Nguyen, Viet; Vorogushyn, Sergiy; Huttenlau, Matthias; Merz, Bruno; Stötter, Johann

    2017-04-01

    The evaluation of potential monetary damage of flooding is an essential part of flood risk management. One possibility to estimate the monetary risk is to analyze long time series of observed flood events and their corresponding damages. In reality, however, only few flood events are documented. This limitation can be overcome by the generation of a set of synthetic, physically and spatial plausible flood events and subsequently the estimation of the resulting monetary damages. In the present work, a set of synthetic flood events is generated by a continuous rainfall-runoff simulation in combination with a coupled weather generator and temporal disaggregation procedure for the study area of Vorarlberg (Austria). Most flood risk studies focus on daily time steps, however, the mesoscale alpine study area is characterized by short concentration times, leading to large differences between daily mean and daily maximum discharge. Accordingly, an hourly time step is needed for the simulations. The hourly metrological input for the rainfall-runoff model is generated in a two-step approach. A synthetic daily dataset is generated by a multivariate and multisite weather generator and subsequently disaggregated to hourly time steps with a k-Nearest-Neighbor model. Following the event generation procedure, the negative consequences of flooding are analyzed. The corresponding flood damage for each synthetic event is estimated by combining the synthetic discharge at representative points of the river network with a loss probability relation for each community in the study area. The loss probability relation is based on exposure and susceptibility analyses on a single object basis (residential buildings) for certain return periods. For these impact analyses official inundation maps of the study area are used. Finally, by analyzing the total event time series of damages, the expected annual damage or losses associated with a certain probability of occurrence can be estimated for

  20. Drivers of flood damage on event level

    DEFF Research Database (Denmark)

    Kreibich, H.; Aerts, J. C. J. H.; Apel, H.

    2016-01-01

    example are the 2002 and 2013 floods in the Elbe and Danube catchments in Germany. The 2002 flood caused the highest economic damage (EUR 11600 million) due to a natural hazard event in Germany. Damage was so high due to extreme flood hazard triggered by extreme precipitation and a high number......-level mitigation measures, 3) more effective early warning and improved coordination of disaster response and 4) a more targeted maintenance of flood defence systems and their deliberate relocation. Thus, despite higher hydrological severity damage due to the 2013 flood was significantly lower than in 2002. In our...

  1. Urban sprawl and flooding in southern California

    Science.gov (United States)

    Rantz, S.E.

    1970-01-01

    The floods of January 1969 in south-coastal California provide a timely example of the effect of urban sprawl on flood damage. Despite recordbreaking, or near recordbreaking, stream discharges, damage was minimal in the older developed areas that are protected against inundation and debris damage by carefully planned flood-control facilities, including debris basins and flood-conveyance channels. By contrast, heavy damage occurred in areas of more recent urban sprawl, where the hazards of inundation and debris or landslide damage have not been taken into consideration, and where the improvement and development of drainage or flood-control facilities have not kept pace with expanding urbanization.

  2. Top flooding modeling with MAAP4 code

    International Nuclear Information System (INIS)

    Brunet-Thibault, E.; Marguet, S.

    2006-01-01

    An engineering top flooding model was developed in MAAP4.04d.4, the severe accident code used in EDF, to simulate the thermal-hydraulic phenomena that should take place if emergency core cooling (ECC) water was injected in hot leg during quenching. In the framework of the ISTC (International Science and Technology Centre), a top flooding test was proposed in the PARAMETER facility (Podolsk, Russia). The MAAP calculation of the PARAMETER top flooding test is presented in this paper. A comparison between top and bottom flooding was made on the bundle test geometry. According to this study, top flooding appears to cool quickly and effectively the upper plenum internals. (author)

  3. Characterization of flood and precipitation events in Southwestern Germany and stochastic simulation of extreme precipitation (Project FLORIS-SV)

    Science.gov (United States)

    Florian, Ehmele; Michael, Kunz

    2016-04-01

    Several major flood events occurred in Germany in the past 15-20 years especially in the eastern parts along the rivers Elbe and Danube. Examples include the major floods of 2002 and 2013 with an estimated loss of about 2 billion Euros each. The last major flood events in the State of Baden-Württemberg in southwest Germany occurred in the years 1978 and 1993/1994 along the rivers Rhine and Neckar with an estimated total loss of about 150 million Euros (converted) each. Flood hazard originates from a combination of different meteorological, hydrological and hydraulic processes. Currently there is no defined methodology available for evaluating and quantifying the flood hazard and related risk for larger areas or whole river catchments instead of single gauges. In order to estimate the probable maximum loss for higher return periods (e.g. 200 years, PML200), a stochastic model approach is designed since observational data are limited in time and space. In our approach, precipitation is linearly composed of three elements: background precipitation, orographically-induces precipitation, and a convectively-driven part. We use linear theory of orographic precipitation formation for the stochastic precipitation model (SPM), which is based on fundamental statistics of relevant atmospheric variables. For an adequate number of historic flood events, the corresponding atmospheric conditions and parameters are determined in order to calculate a probability density function (pdf) for each variable. This method involves all theoretically possible scenarios which may not have happened, yet. This work is part of the FLORIS-SV (FLOod RISk Sparkassen Versicherung) project and establishes the first step of a complete modelling chain of the flood risk. On the basis of the generated stochastic precipitation event set, hydrological and hydraulic simulations will be performed to estimate discharge and water level. The resulting stochastic flood event set will be used to quantify the

  4. 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

  5. Coping with Pluvial Floods by Private Households

    Directory of Open Access Journals (Sweden)

    Viktor Rözer

    2016-07-01

    Full Text Available Pluvial floods have caused severe damage to urban areas in recent years. With a projected increase in extreme precipitation as well as an ongoing urbanization, pluvial flood damage is expected to increase in the future. Therefore, further insights, especially on the adverse consequences of pluvial floods and their mitigation, are needed. To gain more knowledge, empirical damage data from three different pluvial flood events in Germany were collected through computer-aided telephone interviews. Pluvial flood awareness as well as flood experience were found to be low before the respective flood events. The level of private precaution increased considerably after all events, but is mainly focused on measures that are easy to implement. Lower inundation depths, smaller potential losses as compared with fluvial floods, as well as the fact that pluvial flooding may occur everywhere, are expected to cause a shift in damage mitigation from precaution to emergency response. However, an effective implementation of emergency measures was constrained by a low dissemination of early warnings in the study areas. Further improvements of early warning systems including dissemination as well as a rise in pluvial flood preparedness are important to reduce future pluvial flood damage.

  6. Improving Flash Flood Prediction in Multiple Environments

    Science.gov (United States)

    Broxton, P. D.; Troch, P. A.; Schaffner, M.; Unkrich, C.; Goodrich, D.; Wagener, T.; Yatheendradas, S.

    2009-12-01

    Flash flooding is a major concern in many fast responding headwater catchments . There are many efforts to model and to predict these flood events, though it is not currently possible to adequately predict the nature of flash flood events with a single model, and furthermore, many of these efforts do not even consider snow, which can, by itself, or in combination with rainfall events, cause destructive floods. The current research is aimed at broadening the applicability of flash flood modeling. Specifically, we will take a state of the art flash flood model that is designed to work with warm season precipitation in arid environments, the KINematic runoff and EROSion model (KINEROS2), and combine it with a continuous subsurface flow model and an energy balance snow model. This should improve its predictive capacity in humid environments where lateral subsurface flow significantly contributes to streamflow, and it will make possible the prediction of flooding events that involve rain-on-snow or rapid snowmelt. By modeling changes in the hydrologic state of a catchment before a flood begins, we can also better understand the factors or combination of factors that are necessary to produce large floods. Broadening the applicability of an already state of the art flash flood model, such as KINEROS2, is logical because flash floods can occur in all types of environments, and it may lead to better predictions, which are necessary to preserve life and property.

  7. Composite Flood Risk for Virgin Island

    Science.gov (United States)

    The Composite Flood Risk layer combines flood hazard datasets from Federal Emergency Management Agency (FEMA) flood zones, NOAA's Shallow Coastal Flooding, and the National Hurricane Center SLOSH model for Storm Surge inundation for category 1, 2, and 3 hurricanes.Geographic areas are represented by a grid of 10 by 10 meter cells and each cell has a ranking based on variation in exposure to flooding hazards: Moderate, High and Extreme exposure. Geographic areas in each input layers are ranked based on their probability of flood risk exposure. The logic was such that areas exposed to flooding on a more frequent basis were given a higher ranking. Thus the ranking incorporates the probability of the area being flooded. For example, even though a Category 3 storm surge has higher flooding elevations, the likelihood of the occurrence is lower than a Category 1 storm surge and therefore the Category 3 flood area is given a lower exposure ranking. Extreme exposure areas are those areas that are exposed to relatively frequent flooding.The ranked input layers are then converted to a raster for the creation of the composite risk layer by using cell statistics in spatial analysis. The highest exposure ranking for a given cell in any of the three input layers is assigned to the corresponding cell in the composite layer.For example, if an area (a cell) is rank as medium in the FEMA layer, moderate in the SLOSH layer, but extreme in the SCF layer, the cell will be considere

  8. Can we predict the next urban flood?

    DEFF Research Database (Denmark)

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

    2015-01-01

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

  9. Betwixt Droughts and Floods: Flood Management Politics in Thailand

    Directory of Open Access Journals (Sweden)

    Naila Maier-Knapp

    2015-01-01

    Full Text Available Attempting to create greater understanding of the political dynamics that influence domestic disaster relief and management (DRM in Thailand, this article takes a closer look at these dynamics by outlining the main actors involved in flood-related DRM. It acknowledges the importance of international and military actors but emphasises the role of national and subnational authorities. The article then identifies the central issues of DRM governance as capacity and bureaucracy and discusses these through a chronological assessment of the flood crisis in Thailand in 2011, interweaving the colourful domestic politics with various political cleavages and dichotomies, and thereby distinguishing between three main dichotomies which it considers as the central drivers of the political dynamics and institutional development of DRM. These issues can be summarised as old versus new institutions, technocracy versus bureaucracy and centralised (but with direct people-orientation through greater channels of citizenry participation versus decentralised bureaucracy with an indirect orientation towards people.

  10. Modeling urban flood risk territories for Riga city

    Science.gov (United States)

    Piliksere, A.; Sennikovs, J.; Virbulis, J.; Bethers, U.; Bethers, P.; Valainis, A.

    2012-04-01

    Riga, the capital of Latvia, is located on River Daugava at the Gulf of Riga. The main flooding risks of Riga city are: (1) storm caused water setup in South part of Gulf of Riga (storm event), (2) water level increase caused by Daugava River discharge maximums (spring snow melting event) and (3) strong rainfall or rapid snow melting in densely populated urban areas. The first two flooding factors were discussed previously (Piliksere et al, 2011). The aims of the study were (1) the identification of the flood risk situations in densely populated areas, (2) the quantification of the flooding scenarios caused by rain and snow melting events of different return periods nowadays, in the near future (2021-2050), far future (2071-2100) taking into account the projections of climate change, (3) estimation of groundwater level for Riga city, (4) the building and calibration of the hydrological mathematical model based on SWMM (EPA, 2004) for the domain potentially vulnerable for rain and snow melt flooding events, (5) the calculation of rain and snow melting flood events with different return periods, (6) mapping the potentially flooded areas on a fine grid. The time series of short term precipitation events during warm time period of year (id est. rain events) were analyzed for 35 year long time period. Annual maxima of precipitation intensity for events with different duration (5 min; 15 min; 1h; 3h; 6h; 12h; 1 day; 2 days; 4 days; 10 days) were calculated. The time series of long term simultaneous precipitation data and observations of the reduction of thickness of snow cover were analyzed for 27 year long time period. Snow thawing periods were detected and maximum of snow melting intensity for events with different intensity (1day; 2 days; 4 days; 7 days; 10 days) were calculated. According to the occurrence probability six scenarios for each event for nowadays, near and far future with return period once in 5, 10, 20, 50, 100 and 200 years were constructed based on

  11. Receiver function estimated by maximum entropy deconvolution

    Institute of Scientific and Technical Information of China (English)

    吴庆举; 田小波; 张乃铃; 李卫平; 曾融生

    2003-01-01

    Maximum entropy deconvolution is presented to estimate receiver function, with the maximum entropy as the rule to determine auto-correlation and cross-correlation functions. The Toeplitz equation and Levinson algorithm are used to calculate the iterative formula of error-predicting filter, and receiver function is then estimated. During extrapolation, reflective coefficient is always less than 1, which keeps maximum entropy deconvolution stable. The maximum entropy of the data outside window increases the resolution of receiver function. Both synthetic and real seismograms show that maximum entropy deconvolution is an effective method to measure receiver function in time-domain.

  12. A Cascading Storm-Flood-Landslide Guidance System: Development and Application in China

    Science.gov (United States)

    Zeng, Ziyue; Tang, Guoqiang; Long, Di; Ma, Meihong; Hong, Yang

    2016-04-01

    Flash floods and landslides, triggered by storms, often interact and cause cascading effects on human lives and property. Satellite remote sensing data has significant potential use in analysis of these natural hazards. As one of the regions continuously affected by severe flash floods and landslides, Yunnan Province, located in Southwest China, has a complex mountainous hydrometeorology and suffers from frequent heavy rainfalls from May through to late September. Taking Yunnan as a test-bed, this study proposed a Cascading Storm-Flood-Landslide Guidance System to progressively analysis and evaluate the risk of the multi-hazards based on multisource satellite remote sensing data. First, three standardized rainfall amounts (average daily amount in flood seasons, maximum 1h and maximum 6h amount) from the products of Topical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) were used as rainfall indicators to derive the StorM Hazard Index (SMHI). In this process, an integrated approach of the Analytic Hierarchy Process (AHP) and the Information-Entropy theory was adopted to determine the weight of each indicator. Then, land cover and vegetation cover data from the Moderate Resolution Imaging Spectroradiometer (MODIS) products, soil type from the Harmonized World Soil Database (HWSD) soil map, and slope from the Shuttle Radar Topography Mission (SRTM) data were add as semi-static geo-topographical indicators to derive the Flash Flood Hazard Index (FFHI). Furthermore, three more relevant landslide-controlling indicators, including elevation, slope angle and soil text were involved to derive the LandSlide Hazard Index (LSHI). Further inclusion of GDP, population and prevention measures as vulnerability indicators enabled to consecutively predict the risk of storm to flash flood and landslide, respectively. Consequently, the spatial patterns of the hazard indices show that the southeast of Yunnan has more possibility to encounter with storms

  13. Sobre inundaciones y anegamientos / Reflections on floods and flooding

    Directory of Open Access Journals (Sweden)

    Ferrando A., Francisco J.

    2006-11-01

    Full Text Available Respecto a anegamientos e inundaciones, el autor realiza algunas precisiones conceptuales que afectan la gestión de acciones preventivas, la planificación y el ordenamiento territorial; además se ofrece una sistematización del quehacer sobre las inundaciones./ The author punctualizes the concepts regarding preventive actions and territorial planning. Also the article includes a systematized list of actions related to flood management.

  14. Flood of April 1975 at Williamston, Michigan

    Science.gov (United States)

    Knutilla, R.L.; Swallow, L.A.

    1975-01-01

    On April 18 between 5 p.m. and 12 p.m. the city of Williamston experienced an intense rain storm that caused the Red Cedar River and the many small streams in the area to overflow their banks and resulted in the most devastating flood since at least 1904. Local officials estimated a loss of \\$775,000 in property damage. Damage from flooding by the Red Cedar River was caused primarily by inundation, rather than by water moving at high velocity, as is common when many streams are flooded. During the flood of April 1975 many basements were flooded as well as the lower floors of some homes in the flood plain. Additional damage occurred in places when sewers backed up and flooded basements, and when ground water seeped through basement walls and floors—situations that affected many homes including those that were well outside of the flood plain.During the time of flooding the U.S. Geological Survey obtained aerial photography and data on a streamflow to document the disaster. This report shows on a photomosaic base map the extent of flooding along the Red Cedar River at Williamston, during the flood. It also presents data obtained at stream-gaging stations near Williamston, as well as the results of peak-flow discharge measurements made on the Red Cedar River at Michigan State Highway M-52 east of the city. Information on the magnitude of the flood can guide in making decisions pertaining to the use of flood-plains in the area. It is one of a series of reports on the April 1975 flood in the Lansing metropolitan area.

  15. Aquatic chemistry of flood events

    Science.gov (United States)

    Klavins, Maris; Rodinov, Valery

    2015-04-01

    During flood events a major discharge of water and dissolved substances happens. However flood waters very much differs from water composition during low-water events. Aquatic chemistry of flood waters also is of importance at the calculation of loadings as well as they might have major impact on water quality in receiving water bodies (lakes, coastal waters and seas). Further flood regime of rivers is subjected to changes due to climate change and growing impact of human activities. The aim of this study is to analyse water chemical composition changes during flood events in respect to low water periods, character of high-water events and characteristics of the corresponding basin. Within this study, the concentrations of major dissolved substances in the major rivers of Latvia have been studied using monitoring data as well as field studies during high water/ low water events. As territories of studies flows of substances in river basins/subbasins with different land-use character and different anthropogenic impacts has been studied to calculate export values depending on the land-use character. Impact of relations between dissolved substances and relations in respect to budgets has been calculated. The dynamics of DOC, nutrient and major dissolved substance flows depending on landuse pattern and soil properties in Latvia has been described, including emissions by industrial and agricultural production. In these changes evidently climate change signals can be identified. The water chemistry of a large number of rivers during flood events has been determined and the possible impact of water chemical composition on DOC and nutrient flows has been evaluated. Long-term changes (1977-2013) of concentrations of dissolved substances do not follow linear trends but rather show oscillating patterns, indicating impact of natural factors, e.g. changing hydrological and climatic conditions. There is a positive correlation between content of inert dissolved substances and

  16. Use of documentary sources on past flood events for flood risk management and land planning

    Science.gov (United States)

    Cœur, Denis; Lang, Michel

    2008-09-01

    The knowledge of past catastrophic events can improve flood risk mitigation policy, with a better awareness against risk. As such historical information is usually available in Europe for the past five centuries, historians are able to understand how past society dealt with flood risk, and hydrologists can include information on past floods into an adapted probabilistic framework. In France, Flood Risk Mitigation Maps are based either on the largest historical known flood event or on the 100-year flood event if it is greater. Two actions can be suggested in terms of promoting the use of historical information for flood risk management: (1) the development of a regional flood data base, with both historical and current data, in order to get a good feedback on recent events and to improve the flood risk education and awareness; (2) the commitment to keep a persistent/perennial management of a reference network of hydrometeorological observations for climate change studies.

  17. Maximum Power from a Solar Panel

    Directory of Open Access Journals (Sweden)

    Michael Miller

    2010-01-01

    Full Text Available Solar energy has become a promising alternative to conventional fossil fuel sources. Solar panels are used to collect solar radiation and convert it into electricity. One of the techniques used to maximize the effectiveness of this energy alternative is to maximize the power output of the solar collector. In this project the maximum power is calculated by determining the voltage and the current of maximum power. These quantities are determined by finding the maximum value for the equation for power using differentiation. After the maximum values are found for each time of day, each individual quantity, voltage of maximum power, current of maximum power, and maximum power is plotted as a function of the time of day.

  18. Site Specific Probable Maximum Precipitation Estimates and Professional Judgement

    Science.gov (United States)

    Hayes, B. D.; Kao, S. C.; Kanney, J. F.; Quinlan, K. R.; DeNeale, S. T.

    2015-12-01

    State and federal regulatory authorities currently rely upon the US National Weather Service Hydrometeorological Reports (HMRs) to determine probable maximum precipitation (PMP) estimates (i.e., rainfall depths and durations) for estimating flooding hazards for relatively broad regions in the US. PMP estimates for the contributing watersheds upstream of vulnerable facilities are used to estimate riverine flooding hazards while site-specific estimates for small water sheds are appropriate for individual facilities such as nuclear power plants. The HMRs are often criticized due to their limitations on basin size, questionable applicability in regions affected by orographic effects, their lack of consist methods, and generally by their age. HMR-51 for generalized PMP estimates for the United States east of the 105th meridian, was published in 1978 and is sometimes perceived as overly conservative. The US Nuclear Regulatory Commission (NRC), is currently reviewing several flood hazard evaluation reports that rely on site specific PMP estimates that have been commercially developed. As such, NRC has recently investigated key areas of expert judgement via a generic audit and one in-depth site specific review as they relate to identifying and quantifying actual and potential storm moisture sources, determining storm transposition limits, and adjusting available moisture during storm transposition. Though much of the approach reviewed was considered a logical extension of HMRs, two key points of expert judgement stood out for further in-depth review. The first relates primarily to small storms and the use of a heuristic for storm representative dew point adjustment developed for the Electric Power Research Institute by North American Weather Consultants in 1993 in order to harmonize historic storms for which only 12 hour dew point data was available with more recent storms in a single database. The second issue relates to the use of climatological averages for spatially

  19. 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.

  20. Forecasting characteristics of flood effects

    Science.gov (United States)

    Khamutova, M. V.; Rezchikov, A. F.; Kushnikov, V. A.; Ivaschenko, V. A.; Bogomolov, A. S.; Filimonyuk, L. Yu; Dolinina, O. N.; Kushnikova, E. V.; Shulga, T. E.; Tverdokhlebov, V. A.; Fominykh, D. S.

    2018-05-01

    The article presents the development of a mathematical model of the system dynamics. Mathematical model allows forecasting the characteristics of flood effects. Model is based on a causal diagram and is presented by a system of nonlinear differential equations. Simulated characteristics are the nodes of the diagram, and edges define the functional relationships between them. The numerical solution of the system of equations using the Runge-Kutta method was obtained. Computer experiments to determine the characteristics on different time interval have been made and results of experiments have been compared with real data of real flood. The obtained results make it possible to assert that the developed model is valid. The results of study are useful in development of an information system for the operating and dispatching staff of the Ministry of the Russian Federation for Civil Defence, Emergencies and Elimination of Consequences of Natural Disasters (EMERCOM).

  1. Bangladesh floods, cyclones and ENSO

    International Nuclear Information System (INIS)

    Choudhury, A.M.

    1994-04-01

    It has been found that in general there is a reduction of rainfall in all the regions of Bangladesh in all the seasons - premonsoon, monsoon and post monsoon during El Nino years. It has also been observed that in strong El Nino year Bangladesh is not hit by a catastrophic flood or a catastrophic cyclone. In the past, occurrence of famines in this region of the world coincided with El Nino years. The years of weak El Nino or when the El Nino index is positive seem to be favourable for the occurrence of floods and cyclones in Bangladesh. A theory of the modulation of the monsoon in Bangladesh by the Walker circulation has been described in the paper. (author). 14 refs, 7 figs, 1 tab

  2. Contaminated sediment transport during floods

    International Nuclear Information System (INIS)

    Fontaine, T.A.

    1992-01-01

    Over the past 48 years, operations and waste disposal activities at Oak Ridge National Laboratory have resulted in the contamination of parts of the White Oak Creek catchment. The contaminants presenting the highest risk to human health and the environment are particle reactive and are associated with the soils and sediments in the White Oak Creek drainage system. The erosion of these sediments during floods can result in the transport of contaminants both within the catchment and off-site into the Clinch River. A data collection program and a modeling investigation are being used to evaluate the probability of contaminated sediment transport during floods and to develop strategies for controlling off-site transport under present and future conditions

  3. Computerized evaluation of flood impact

    International Nuclear Information System (INIS)

    Gagnon, J.; Quach, T.T.; Marche, C.; Lessard, G.

    1998-01-01

    A computerized evaluation process for assessing the economic impacts of a potential dam failure is described. The DOMINO software, which was developed by Hydro-Quebec, takes into account flow data from dam break simulations of floods, the territory involved, plus the economic evaluations of the real estate and infrastructures affected. Some examples of software applications and impact evaluations are presented. The principal elements involved in estimating economic or other types of impacts induced by natural flooding or dam failure, are: (1) flow forecasting, (2) defining the contour of the involved territory, and (3) accounting for the various impacts identified in the affected zone. Owing to its wide range of functions and utilities, DOMINO has proven to be a very useful, user-friendly and portable decision-making tool. 5 refs., 6 tabs

  4. A system for generating long streamflow records for study of floods of long return period: Phase 2

    International Nuclear Information System (INIS)

    Franz, D.D.; Kraeger, B.A.; Linsley, R.K.

    1989-02-01

    Knowledge of the return periods of large floods is required to make risk analyses for nuclear power plants subject to flooding from rivers. The system reported here combined the stochastic simulation of hourly rainfall data and daily pan evaporation data with the deterministic simulation of streamflow by using the synthetic rainfall and evaporation data as input to a calibrated rainfall runoff model. The sequence of annual maximum flood peaks from a synthetic record of 10,000 years or more was then analyzed to obtain estimates of flood frequency. The reasonableness of the flood frequency results must be evaluated on the degree of mimicry of the key characteristics of the observed rainfall data and the ability of the rainfall-runoff model to mimic the observed flood frequency during the calibration period. On this basis, the flood frequency results appeared to be a reasonable extrapolation of the data used in defining the model parameters. There is a need to develop regional parameters for the stochastic models and to conduct research on the relationship between the stochastic structure of rainfall and stochastic structure of flood frequency. The methodology is applicable, assuming a highly skilled analyst, to watersheds similar to those already tested

  5. Vulnerability assessment and mitigation for the Chinese railway system under floods

    International Nuclear Information System (INIS)

    Hong, Liu; Ouyang, Min; Peeta, Srinivas; He, Xiaozheng; Yan, Yongze

    2015-01-01

    The economy of China and the travel needs of its citizens depend significantly on the continuous and reliable services provided by its railway system. However, this system is subject to frequent natural hazards, such as floods, earthquakes, and debris flow. A mechanism to assess the railway system vulnerability under these hazards and the design of effective vulnerability mitigation strategies are essential to the reliable functioning of the railway system. This article proposes a comprehensive methodology to quantitatively assess the railway system vulnerability under floods using historical data and GIS technology. The proposed methodology includes a network representation of the railway system, the generation of flood event scenarios, a method to estimate railway link vulnerability, and a quantitative vulnerability value computation approach. The railway system vulnerability is evaluated in terms of its service disruption related to the number of interrupted trains and the durations of interruption. A maintenance strategy to mitigate vulnerability is proposed that simultaneously considers link vulnerability and number of trains using it. Numerical experiments show that the flood-induced vulnerability of the proposed representation of the Chinese railway system reaches its maximum monthly value in July, and the proposed vulnerability mitigation strategy is more effective compared to other strategies. - Highlights: • We propose a methodology to assess flood-induced railway system vulnerability. • Railway system vulnerability is evaluated in terms of its service disruption. • Chinese railway system reaches its maximum monthly vulnerability in July. • We propose an effective maintenance strategy considering link vulnerability and burden

  6. Floods and human health: a systematic review.

    Science.gov (United States)

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

    2012-10-15

    Floods are the most common type of disaster globally, responsible for almost 53,000 deaths in the last decade alone (23:1 low- versus high-income countries). This review assessed recent epidemiological evidence on the impacts of floods on human health. Published articles (2004-2011) on the quantitative relationship between floods and health were systematically reviewed. 35 relevant epidemiological studies were identified. Health outcomes were categorized into short- and long-term and were found to depend on the flood characteristics and people's vulnerability. It was found that long-term health effects are currently not well understood. Mortality rates were found to increase by up to 50% in the first year post-flood. After floods, it was found there is an increased risk of disease outbreaks such as hepatitis E, gastrointestinal disease and leptospirosis, particularly in areas with poor hygiene and displaced populations. Psychological distress in survivors (prevalence 8.6% to 53% two years post-flood) can also exacerbate their physical illness. There is a need for effective policies to reduce and prevent flood-related morbidity and mortality. Such steps are contingent upon the improved understanding of potential health impacts of floods. Global trends in urbanization, burden of disease, malnutrition and maternal and child health must be better reflected in flood preparedness and mitigation programs. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  7. Structural master plan of flood mitigation measures

    Directory of Open Access Journals (Sweden)

    A. Heidari

    2009-01-01

    Full Text Available Flood protection is one of the practical methods in damage reduction. Although it not possible to be completely protected from flood disaster but major part of damages can be reduced by mitigation plans. In this paper, the optimum flood mitigation master plan is determined by economic evaluation in trading off between the construction costs and expected value of damage reduction as the benefits. Size of the certain mitigation alternative is also be obtained by risk analysis by accepting possibility of flood overtopping. Different flood mitigation alternatives are investigated from various aspects in the Dez and Karun river floodplain areas as a case study in south west of IRAN. The results show that detention dam and flood diversion are the best alternatives of flood mitigation methods as well as enforcing the flood control purpose of upstream multipurpose reservoirs. Dyke and levees are not mostly justifiable because of negative impact on down stream by enhancing routed flood peak discharge magnitude and flood damages as well.

  8. Predicting floods with Flickr tags.

    Science.gov (United States)

    Tkachenko, Nataliya; Jarvis, Stephen; Procter, Rob

    2017-01-01

    Increasingly, user generated content (UGC) in social media postings and their associated metadata such as time and location stamps are being used to provide useful operational information during natural hazard events such as hurricanes, storms and floods. The main advantage of these new sources of data are twofold. First, in a purely additive sense, they can provide much denser geographical coverage of the hazard as compared to traditional sensor networks. Second, they provide what physical sensors are not able to do: By documenting personal observations and experiences, they directly record the impact of a hazard on the human environment. For this reason interpretation of the content (e.g., hashtags, images, text, emojis, etc) and metadata (e.g., keywords, tags, geolocation) have been a focus of much research into social media analytics. However, as choices of semantic tags in the current methods are usually reduced to the exact name or type of the event (e.g., hashtags '#Sandy' or '#flooding'), the main limitation of such approaches remains their mere nowcasting capacity. In this study we make use of polysemous tags of images posted during several recent flood events and demonstrate how such volunteered geographic data can be used to provide early warning of an event before its outbreak.

  9. Bayesian flood forecasting methods: A review

    Science.gov (United States)

    Han, Shasha; Coulibaly, Paulin

    2017-08-01

    Over the past few decades, floods have been seen as one of the most common and largely distributed natural disasters in the world. If floods could be accurately forecasted in advance, then their negative impacts could be greatly minimized. It is widely recognized that quantification and reduction of uncertainty associated with the hydrologic forecast is of great importance for flood estimation and rational decision making. Bayesian forecasting system (BFS) offers an ideal theoretic framework for uncertainty quantification that can be developed for probabilistic flood forecasting via any deterministic hydrologic model. It provides suitable theoretical structure, empirically validated models and reasonable analytic-numerical computation method, and can be developed into various Bayesian forecasting approaches. This paper presents a comprehensive review on Bayesian forecasting approaches applied in flood forecasting from 1999 till now. The review starts with an overview of fundamentals of BFS and recent advances in BFS, followed with BFS application in river stage forecasting and real-time flood forecasting, then move to a critical analysis by evaluating advantages and limitations of Bayesian forecasting methods and other predictive uncertainty assessment approaches in flood forecasting, and finally discusses the future research direction in Bayesian flood forecasting. Results show that the Bayesian flood forecasting approach is an effective and advanced way for flood estimation, it considers all sources of uncertainties and produces a predictive distribution of the river stage, river discharge or runoff, thus gives more accurate and reliable flood forecasts. Some emerging Bayesian forecasting methods (e.g. ensemble Bayesian forecasting system, Bayesian multi-model combination) were shown to overcome limitations of single model or fixed model weight and effectively reduce predictive uncertainty. In recent years, various Bayesian flood forecasting approaches have been

  10. Scaling the flood regime with the soil hydraulic properties of the catchment

    Science.gov (United States)

    Peña Rojas, Luis Eduardo; Francés García, Félix; Barrios Peña, Miguel

    2015-04-01

    The spatial land cover distribution and soil type affect the hydraulic properties of soils, facilitating or retarding the infiltration rate and the response of a catchment during flooding events. This research analyzes: 1) the effect of land cover use in different time periods as a source of annual maximum flood records nonstationarity; 2) the scalability of the relationship between soil hydraulic properties of the catchment (initial abstractions, upper soil capillary storage and vertical and horizontal hydraulic conductivity) and the flood regime. The study was conducted in Combeima River basin in Colombia - South America and it was modelled the changes in the land uses registered in 1991, 2000, 2002 and 2007, using distributed hydrological modelling and nonparametric tests. The results showed that changes in land use affect hydraulic properties of soil and it has influence on the magnitude of flood peaks. What is a new finding is that this behavior is scalable with the soil hydraulic properties of the catchment flood moments have a simple scaling behavior and the peaks flow increases with higher values of capillary soil storage, whereas higher values, the peaks decreased. Finally it was applied Generalized Extreme Values and it was found scalable behavior in the parameters of the probability distribution function. The results allowed us to find a relationship between soil hydraulic properties and the behavior of flood regime in the basin studied.

  11. Estimation of initiating event frequency for external flood events by extreme value theorem

    International Nuclear Information System (INIS)

    Chowdhury, Sourajyoti; Ganguly, Rimpi; Hari, Vibha

    2017-01-01

    External flood is an important common cause initiating event in nuclear power plants (NPPs). It may potentially lead to severe core damage (SCD) by first causing the failure of the systems required for maintaining the heat sinks and then by contributing to failures of engineered systems designed to mitigate such failures. The sample NPP taken here is twin 220 MWe Indian standard pressurized heavy water reactor (PHWR) situated inland. A comprehensive in-house Level-1 internal event PSA for full power had already been performed. External flood assessment was further conducted in area of external hazard risk assessment in response to post-Fukushima measures taken in nuclear industries. The present paper describes the methodology to calculate initiating event (IE) frequency for external flood events for the sample inland Indian NPP. General extreme value (GEV) theory based on maximum likelihood method (MLM) and order statistics approach (OSA) is used to analyse the rainfall data for the site. Thousand-year return level and necessary return periods for extreme rainfall are evaluated. These results along with plant-specific topographical calculations quantitatively establish that external flooding resulting from upstream dam break, river flooding and heavy rainfall (flash flood) would be unlikely for the sample NPP in consideration.

  12. A look at the links between drainage density and flood statistics

    Directory of Open Access Journals (Sweden)

    A. Montanari

    2009-07-01

    Full Text Available We investigate the links between the drainage density of a river basin and selected flood statistics, namely, mean, standard deviation, coefficient of variation and coefficient of skewness of annual maximum series of peak flows. The investigation is carried out through a three-stage analysis. First, a numerical simulation is performed by using a spatially distributed hydrological model in order to highlight how flood statistics change with varying drainage density. Second, a conceptual hydrological model is used in order to analytically derive the dependence of flood statistics on drainage density. Third, real world data from 44 watersheds located in northern Italy were analysed. The three-level analysis seems to suggest that a critical value of the drainage density exists for which a minimum is attained in both the coefficient of variation and the absolute value of the skewness coefficient. Such minima in the flood statistics correspond to a minimum of the flood quantile for a given exceedance probability (i.e., recurrence interval. Therefore, the results of this study may provide useful indications for flood risk assessment in ungauged basins.

  13. Spatial and temporal sensitivity of hydrogeomorphic responceand recovery to deforestation, Agriculture, and floods

    Science.gov (United States)

    Fitzpatrick, F.A.; Knox, J.C.

    2000-01-01

    Clear-cut logging followed by agricultural activity caused hydrologic and geomorphic changes in North Fish Creek, a Wisconsin tributary to Lake Superior. Hydro-geomorphic responses to changes in land use were sensitive to the location of reaches along the main stem and to the relative timing of large floods. Hydrologic and sediment-load modeling indicates that flood peaks were three times larger and sediment loads were five times larger during maximum agricultural activity in the 1920s and 1930s than prior to about 1890, when forest cover was dominant. Following logging, overbank sedimentation rates in the lower main stem increased four to six times above pre-settlement rates. Accelerated streambank and channel erosion in the upper main stem have been and continue to be primary sources of sediment to downstream reaches. Extreme floods in 1941 and 1946, followed by frequent moderate floods through 1954, caused extensive geomorphic changes along the entire main stem. Sedimentation rates in the lower main stem may have decreased in the last several decades as agricultural activity declined. However, geomorphic recovery is slow, as incised channels in the upper main stem function as efficient conveyors of watershed surface runoff and thereby continue to promote flooding and sedimentation problems downstream. [Key words: fluvial geomorphology, floods, erosion, sedimentation, deforestation, agriculture.].

  14. Simulation of flooding waves in vertical churn flow

    Energy Technology Data Exchange (ETDEWEB)

    Tekavčič, Matej, E-mail: matej.tekavcic@ijs.si; Končar, Boštjan; Kljenak, Ivo

    2016-04-01

    Highlights: • Flooding waves in air–water churn flow in a vertical pipe were studied. • Simulations using two-fluid model with interface sharpening were performed. • Calculated wave amplitudes agree with existing experimental data. • Contributions of force terms in the liquid momentum balance equation are presented. - Abstract: A transient simulation of flooding waves in the churn flow of air and water in a vertical pipe is performed by the means of two-fluid modelling approach with interface sharpening. The gas and liquid phases are considered immiscible and incompressible with no mass transfer between them. Inter-phase coupling of momentum is realized via interface drag force which is based on the interface area density and the relative velocity between the phases. Surface tension effects are modelled with the Continuum Surface Model. The flow is assumed isothermal. Turbulence is modelled for each phase separately using the two-equation eddy viscosity approach. Results are compared with the reported experimental data for churn flow regime in a vertical pipe (Wang et al., 2011a). Reynolds numbers of the gas flow are in the range from 6000 to 10,000, while the liquid mass flow rate upwards ranges from 25 to 32 g/s. Prediction of critical and maximum amplitudes of the flooding waves show good agreement with experimental values. Results for wave frequencies indicate significant deviations, which can be attributed to the choice of the liquid inlet model.

  15. Simulation of flooding waves in vertical churn flow

    International Nuclear Information System (INIS)

    Tekavčič, Matej; Končar, Boštjan; Kljenak, Ivo

    2016-01-01

    Highlights: • Flooding waves in air–water churn flow in a vertical pipe were studied. • Simulations using two-fluid model with interface sharpening were performed. • Calculated wave amplitudes agree with existing experimental data. • Contributions of force terms in the liquid momentum balance equation are presented. - Abstract: A transient simulation of flooding waves in the churn flow of air and water in a vertical pipe is performed by the means of two-fluid modelling approach with interface sharpening. The gas and liquid phases are considered immiscible and incompressible with no mass transfer between them. Inter-phase coupling of momentum is realized via interface drag force which is based on the interface area density and the relative velocity between the phases. Surface tension effects are modelled with the Continuum Surface Model. The flow is assumed isothermal. Turbulence is modelled for each phase separately using the two-equation eddy viscosity approach. Results are compared with the reported experimental data for churn flow regime in a vertical pipe (Wang et al., 2011a). Reynolds numbers of the gas flow are in the range from 6000 to 10,000, while the liquid mass flow rate upwards ranges from 25 to 32 g/s. Prediction of critical and maximum amplitudes of the flooding waves show good agreement with experimental values. Results for wave frequencies indicate significant deviations, which can be attributed to the choice of the liquid inlet model.

  16. Going beyond the flood insurance rate map: insights from flood hazard map co-production

    Directory of Open Access Journals (Sweden)

    A. Luke

    2018-04-01

    Full Text Available Flood hazard mapping in the United States (US is deeply tied to the National Flood Insurance Program (NFIP. Consequently, publicly available flood maps provide essential information for insurance purposes, but they do not necessarily provide relevant information for non-insurance aspects of flood risk management (FRM such as public education and emergency planning. Recent calls for flood hazard maps that support a wider variety of FRM tasks highlight the need to deepen our understanding about the factors that make flood maps useful and understandable for local end users. In this study, social scientists and engineers explore opportunities for improving the utility and relevance of flood hazard maps through the co-production of maps responsive to end users' FRM needs. Specifically, two-dimensional flood modeling produced a set of baseline hazard maps for stakeholders of the Tijuana River valley, US, and Los Laureles Canyon in Tijuana, Mexico. Focus groups with natural resource managers, city planners, emergency managers, academia, non-profit, and community leaders refined the baseline hazard maps by triggering additional modeling scenarios and map revisions. Several important end user preferences emerged, such as (1 legends that frame flood intensity both qualitatively and quantitatively, and (2 flood scenario descriptions that report flood magnitude in terms of rainfall, streamflow, and its relation to an historic event. Regarding desired hazard map content, end users' requests revealed general consistency with mapping needs reported in European studies and guidelines published in Australia. However, requested map content that is not commonly produced included (1 standing water depths following the flood, (2 the erosive potential of flowing water, and (3 pluvial flood hazards, or flooding caused directly by rainfall. We conclude that the relevance and utility of commonly produced flood hazard maps can be most improved by illustrating

  17. Going beyond the flood insurance rate map: insights from flood hazard map co-production

    Science.gov (United States)

    Luke, Adam; Sanders, Brett F.; Goodrich, Kristen A.; Feldman, David L.; Boudreau, Danielle; Eguiarte, Ana; Serrano, Kimberly; Reyes, Abigail; Schubert, Jochen E.; AghaKouchak, Amir; Basolo, Victoria; Matthew, Richard A.

    2018-04-01

    Flood hazard mapping in the United States (US) is deeply tied to the National Flood Insurance Program (NFIP). Consequently, publicly available flood maps provide essential information for insurance purposes, but they do not necessarily provide relevant information for non-insurance aspects of flood risk management (FRM) such as public education and emergency planning. Recent calls for flood hazard maps that support a wider variety of FRM tasks highlight the need to deepen our understanding about the factors that make flood maps useful and understandable for local end users. In this study, social scientists and engineers explore opportunities for improving the utility and relevance of flood hazard maps through the co-production of maps responsive to end users' FRM needs. Specifically, two-dimensional flood modeling produced a set of baseline hazard maps for stakeholders of the Tijuana River valley, US, and Los Laureles Canyon in Tijuana, Mexico. Focus groups with natural resource managers, city planners, emergency managers, academia, non-profit, and community leaders refined the baseline hazard maps by triggering additional modeling scenarios and map revisions. Several important end user preferences emerged, such as (1) legends that frame flood intensity both qualitatively and quantitatively, and (2) flood scenario descriptions that report flood magnitude in terms of rainfall, streamflow, and its relation to an historic event. Regarding desired hazard map content, end users' requests revealed general consistency with mapping needs reported in European studies and guidelines published in Australia. However, requested map content that is not commonly produced included (1) standing water depths following the flood, (2) the erosive potential of flowing water, and (3) pluvial flood hazards, or flooding caused directly by rainfall. We conclude that the relevance and utility of commonly produced flood hazard maps can be most improved by illustrating pluvial flood hazards

  18. Sustainable flood memories, lay knowledges and the development of community resilience to future flood risk

    Directory of Open Access Journals (Sweden)

    McEwen Lindsey

    2016-01-01

    Full Text Available Shifts to devolved flood risk management in the UK pose questions about how the changing role of floodplain residents in community-led adaptation planning can be supported and strengthened. This paper shares insights from an interdisciplinary research project that has proposed the concept of ‘sustainable flood memory’ in the context of effective flood risk management. The research aimed to increase understanding of whether and how flood memories from the UK Summer 2007 extreme floods provide a platform for developing lay knowledges and flood resilience. The project investigated what factors link flood memory and lay knowledges of flooding, and how these connect and disconnect during and after flood events. In particular, and relation to flood governance directions, we sought to explore how such memories might play a part in individual and community resilience. The research presented here explores some key themes drawn from semi-structured interviews with floodplain residents with recent flood experiences in contrasting demographic and physical settings in the lower River Severn catchment. These include changing practices in making flood memories and materialising flood knowledge and the roles of active remembering and active forgetting.

  19. Estimation of flood environmental effects using flood zone mapping techniques in Halilrood Kerman, Iran.

    Science.gov (United States)

    Boudaghpour, Siamak; Bagheri, Majid; Bagheri, Zahra

    2014-01-01

    High flood occurrences with large environmental damages have a growing trend in Iran. Dynamic movements of water during a flood cause different environmental damages in geographical areas with different characteristics such as topographic conditions. In general, environmental effects and damages caused by a flood in an area can be investigated from different points of view. The current essay is aiming at detecting environmental effects of flood occurrences in Halilrood catchment area of Kerman province in Iran using flood zone mapping techniques. The intended flood zone map was introduced in four steps. Steps 1 to 3 pave the way to calculate and estimate flood zone map in the understudy area while step 4 determines the estimation of environmental effects of flood occurrence. Based on our studies, wide range of accuracy for estimating the environmental effects of flood occurrence was introduced by using of flood zone mapping techniques. Moreover, it was identified that the existence of Jiroft dam in the study area can decrease flood zone from 260 hectares to 225 hectares and also it can decrease 20% of flood peak intensity. As a result, 14% of flood zone in the study area can be saved environmentally.

  20. FEBA - flooding experiments with blocked arrays

    International Nuclear Information System (INIS)

    Ihle, P.; Rust, K.

    1984-03-01

    Flooding Experiments with Blocked Arrays (FEBA) were conducted to study the effectiveness of the emergency core cooling of PWR with deformed claddings of some fuel rod clusters. Full length bundles of 1x5 as well as 5x5 electrically heated rods of PWR dimensions were used for a number of separate effect test series with various blockage geometries simulating ballooned fuel rod claddings. The results of the eight test series performed with the 5x5 rod bundle using full decay heat show the effects of grid spacers and coplanar coolant channel blockages with and without bypass on reflood heat transfer. The cooling enhancement downstream of grid spacers as well as within and downstream of blockages of 62% blockage ratio mainly occurs during the early portion of reflood. For the 90% blockage ratio only maximum cladding temperatures downstream of the blockage were slightly higher (max. 50 K) than in the bypass area. The purpose of the investigations was to obtain an insight into the most important heat transfer mechanisms to broaden the data base for the development and assessment of improved thermal-hydraulic models. (orig.) [de

  1. Maximum permissible voltage of YBCO coated conductors

    Energy Technology Data Exchange (ETDEWEB)

    Wen, J.; Lin, B.; Sheng, J.; Xu, J.; Jin, Z. [Department of Electrical Engineering, Shanghai Jiao Tong University, Shanghai (China); Hong, Z., E-mail: zhiyong.hong@sjtu.edu.cn [Department of Electrical Engineering, Shanghai Jiao Tong University, Shanghai (China); Wang, D.; Zhou, H.; Shen, X.; Shen, C. [Qingpu Power Supply Company, State Grid Shanghai Municipal Electric Power Company, Shanghai (China)

    2014-06-15

    Highlights: • We examine three kinds of tapes’ maximum permissible voltage. • We examine the relationship between quenching duration and maximum permissible voltage. • Continuous I{sub c} degradations under repetitive quenching where tapes reaching maximum permissible voltage. • The relationship between maximum permissible voltage and resistance, temperature. - Abstract: Superconducting fault current limiter (SFCL) could reduce short circuit currents in electrical power system. One of the most important thing in developing SFCL is to find out the maximum permissible voltage of each limiting element. The maximum permissible voltage is defined as the maximum voltage per unit length at which the YBCO coated conductors (CC) do not suffer from critical current (I{sub c}) degradation or burnout. In this research, the time of quenching process is changed and voltage is raised until the I{sub c} degradation or burnout happens. YBCO coated conductors test in the experiment are from American superconductor (AMSC) and Shanghai Jiao Tong University (SJTU). Along with the quenching duration increasing, the maximum permissible voltage of CC decreases. When quenching duration is 100 ms, the maximum permissible of SJTU CC, 12 mm AMSC CC and 4 mm AMSC CC are 0.72 V/cm, 0.52 V/cm and 1.2 V/cm respectively. Based on the results of samples, the whole length of CCs used in the design of a SFCL can be determined.

  2. Flood hazards for nuclear power plants

    International Nuclear Information System (INIS)

    Yen, B.C.

    1988-01-01

    Flooding hazards for nuclear power plants may be caused by various external geophysical events. In this paper the hydrologic hazards from flash floods, river floods and heavy rain at the plant site are considered. Depending on the mode of analysis, two types of hazard evaluation are identified: 1) design hazard which is the probability of flooding over an expected service period, and 2) operational hazard which deals with real-time forecasting of the probability of flooding of an incoming event. Hazard evaluation techniques using flood frequency analysis can only be used for type 1) design hazard. Evaluation techniques using rainfall-runoff simulation or multi-station correlation can be used for both types of hazard prediction. (orig.)

  3. Evaluation of internal flooding in a BWR

    International Nuclear Information System (INIS)

    Shiu, K.; Papazoglou, I.A.; Sun, Y.H.; Anavim, E.; Ilberg, D.

    1985-01-01

    Flooding inside a nuclear power station is capable of concurrently disabling redundant safety systems. This paper presents the results of a recent review study performed on internally-generated floods inside a boiling water reactor (BWR) reactor building. The study evaluated the flood initiator frequency due to either maintenance or ruptures using Markovian models. A time phased event tree approach was adopted to quantify the core damage frequency based on the flood initiator frequency. It is found in the study that the contribution to the total core damage due to internal flooding events is not insignificant and is comparable to other transient contributors. The findings also indicate that the operator plays an important role in the prevention as well as the mitigation of a flooding event

  4. [Climate changes, floods, and health consequences].

    Science.gov (United States)

    Michelozzi, Paola; de' Donato, Francesca

    2014-02-01

    In the European Region, floods are the most common natural disaster, causing extensive damage and disruption. In Italy, it has been estimated that over 68% of municipalities are at high hydrogeological risk and with the recent intense rainfall events local populations have been facing severe disruptions. The health consequences of floods are wide ranging and are dependent upon the vulnerability of the environment and the local population. Health effects can be a direct or indirect consequence of flooding. The immediate health impacts of floods include drowning, heart attacks, injuries and hypothermia. The indirect effects include, injuries and infections, water-borne infectious disease, mental health problems, respiratory disease and allergies in both the medium and long term after a flood. Future efforts should be addressed to integrate health preparedness and prevention measures into emergency flood plans and hydrological warning systems.

  5. Variation of Probable Maximum Precipitation in Brazos River Basin, TX

    Science.gov (United States)

    Bhatia, N.; Singh, V. P.

    2017-12-01

    The Brazos River basin, the second-largest river basin by area in Texas, generates the highest amount of flow volume of any river in a given year in Texas. With its headwaters located at the confluence of Double Mountain and Salt forks in Stonewall County, the third-longest flowline of the Brazos River traverses within narrow valleys in the area of rolling topography of west Texas, and flows through rugged terrains in mainly featureless plains of central Texas, before its confluence with Gulf of Mexico. Along its major flow network, the river basin covers six different climate regions characterized on the basis of similar attributes of vegetation, temperature, humidity, rainfall, and seasonal weather changes, by National Oceanic and Atmospheric Administration (NOAA). Our previous research on Texas climatology illustrated intensified precipitation regimes, which tend to result in extreme flood events. Such events have caused huge losses of lives and infrastructure in the Brazos River basin. Therefore, a region-specific investigation is required for analyzing precipitation regimes along the geographically-diverse river network. Owing to the topographical and hydroclimatological variations along the flow network, 24-hour Probable Maximum Precipitation (PMP) was estimated for different hydrologic units along the river network, using the revised Hershfield's method devised by Lan et al. (2017). The method incorporates the use of a standardized variable describing the maximum deviation from the average of a sample scaled by the standard deviation of the sample. The hydrometeorological literature identifies this method as more reasonable and consistent with the frequency equation. With respect to the calculation of stable data size required for statistically reliable results, this study also quantified the respective uncertainty associated with PMP values in different hydrologic units. The corresponding range of return periods of PMPs in different hydrologic units was

  6. Towards modelling flood protection investment as a coupled human and natural system

    Science.gov (United States)

    O'Connell, P. E.; O'Donnell, G.

    2014-01-01

    Due to a number of recent high-profile flood events and the apparent threat from global warming, governments and their agencies are under pressure to make proactive investments to protect people living in floodplains. However, adopting a proactive approach as a universal strategy is not affordable. It has been argued that delaying expensive and essentially irreversible capital decisions could be a prudent strategy in situations with high future uncertainty. This paper firstly uses Monte Carlo simulation to explore the performance of proactive and reactive investment strategies using a rational cost-benefit approach in a natural system with varying levels of persistence/interannual variability in annual maximum floods. It is found that, as persistence increases, there is a change in investment strategy optimality from proactive to reactive. This could have implications for investment strategies under the increasingly variable climate that is expected with global warming. As part of the emerging holistic approaches to flood risk management, there is increasing emphasis on stakeholder participation in determining where and when flood protection investments are made, and so flood risk management is becoming more people-centred. As a consequence, multiple actors are involved in the decision-making process, and the social sciences are assuming an increasingly important role in flood risk management. There is a need for modelling approaches which can couple the natural and human system elements. It is proposed that coupled human and natural system (CHANS) modelling could play an important role in understanding the motivations, actions and influence of citizens and institutions and how these impact on the effective delivery of flood protection investment. A framework for using agent-based modelling of human activities leading to flood investments is outlined, and some of the challenges associated with implementation are discussed.

  7. Potential increase in floods in California's Sierra Nevada under future climate projections

    Science.gov (United States)

    Das, T.; Dettinger, M.D.; Cayan, D.R.; Hidalgo, H.G.

    2011-01-01

    California's mountainous topography, exposure to occasional heavily moisture-laden storm systems, and varied communities and infrastructures in low lying areas make it highly vulnerable to floods. An important question facing the state-in terms of protecting the public and formulating water management responses to climate change-is "how might future climate changes affect flood characteristics in California?" To help address this, we simulate floods on the western slopes of the Sierra Nevada Mountains, the state's primary catchment, based on downscaled daily precipitation and temperature projections from three General Circulation Models (GCMs). These climate projections are fed into the Variable Infiltration Capacity (VIC) hydrologic model, and the VIC-simulated streamflows and hydrologic conditions, from historical and from projected climate change runs, allow us to evaluate possible changes in annual maximum 3-day flood magnitudes and frequencies of floods. By the end of the 21st Century, all projections yield larger-than-historical floods, for both the Northern Sierra Nevada (NSN) and for the Southern Sierra Nevada (SSN). The increases in flood magnitude are statistically significant (at p models, while under the third scenario, GFDL CM2. 1, frequencies remain constant or decline slightly, owing to an overall drying trend. These increases appear to derive jointly from increases in heavy precipitation amount, storm frequencies, and days with more precipitation falling as rain and less as snow. Increases in antecedent winter soil moisture also play a role in some areas. Thus, a complex, as-yet unpredictable interplay of several different climatic influences threatens to cause increased flood hazards in California's complex western Sierra landscapes. ?? 2011 Springer Science+Business Media B.V.

  8. On the link between extreme floods and excess monsoon epochs in South Asia

    Energy Technology Data Exchange (ETDEWEB)

    Kale, Vishwas [University of Pune, Department of Geography, Pune (India)

    2012-09-15

    This paper provides a synoptic view of extreme monsoon floods on all the nine large rivers of South Asia and their association with the excess (above-normal) monsoon rainfall periods. Annual maximum flood series for 18 gauging stations spread over four countries (India, Pakistan, Bangladesh and Nepal) and long-term monsoon rainfall data were analyzed to ascertain whether the extreme floods were clustered in time and whether they coincided with multi-decade excess monsoon rainfall epochs at the basin level. Simple techniques, such as the Cramer's t-test, regression and Mann-Kendall (MK) tests and Hurst method were used to evaluate the trends and patterns of the flood and rainfall series. MK test reveals absence of any long-term tendency in all the series. However, the Cramer's t test and Hurst-Mandelbrot rescaled range statistic provide evidence that both rainfall and flood time series are persistent. Using the Cramer's t-test the excess monsoon epochs for each basin were identified. The excess monsoon periods for different basins were found to be highly asynchronous with respect to duration as well as the beginning and end. Three main conclusions readily emerge from the analyses. Extreme floods (>90th percentile) in South Asia show a tendency to cluster in time. About three-fourth of the extreme floods have occurred during the excess monsoon periods between {proportional_to}1840 and 2000 AD, implying a noteworthy link between the two. The frequency of large floods was higher during the post-1940 period in general and during three decades (1940s, 1950s and 1980s) in particular. (orig.)

  9. Projections of Flood Risk using Credible Climate Signals in the Ohio River Basin

    Science.gov (United States)

    Schlef, K.; Robertson, A. W.; Brown, C.

    2017-12-01

    Estimating future hydrologic flood risk under non-stationary climate is a key challenge to the design of long-term water resources infrastructure and flood management strategies. In this work, we demonstrate how projections of large-scale climate patterns can be credibly used to create projections of long-term flood risk. Our study area is the northwest region of the Ohio River Basin in the United States Midwest. In the region, three major teleconnections have been previously demonstrated to affect synoptic patterns that influence extreme precipitation and streamflow: the El Nino Southern Oscillation, the Pacific North American pattern, and the Pacific Decadal Oscillation. These teleconnections are strongest during the winter season (January-March), which also experiences the greatest number of peak flow events. For this reason, flood events are defined as the maximum daily streamflow to occur in the winter season. For each gage in the region, the location parameter of a log Pearson type 3 distribution is conditioned on the first principal component of the three teleconnections to create a statistical model of flood events. Future projections of flood risk are created by forcing the statistical model with projections of the teleconnections from general circulation models selected for skill. We compare the results of our method to the results of two other methods: the traditional model chain (i.e., general circulation model projections to downscaling method to hydrologic model to flood frequency analysis) and that of using the historic trend. We also discuss the potential for developing credible projections of flood events for the continental United States.

  10. 44 CFR 78.6 - Flood Mitigation Plan approval process.

    Science.gov (United States)

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Flood Mitigation Plan..., DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program FLOOD MITIGATION ASSISTANCE § 78.6 Flood Mitigation Plan approval process. The State POC will forward all Flood...

  11. 44 CFR 78.5 - Flood Mitigation Plan development.

    Science.gov (United States)

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Flood Mitigation Plan..., DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program FLOOD MITIGATION ASSISTANCE § 78.5 Flood Mitigation Plan development. A Flood Mitigation Plan will articulate a...

  12. 78 FR 52955 - Changes in Flood Hazard Determinations

    Science.gov (United States)

    2013-08-27

    ... community that the Deputy Associate Administrator for Mitigation reconsider the changes. The flood hazard...; Internal Agency Docket No. FEMA-B-1349] Changes in Flood Hazard Determinations AGENCY: Federal Emergency... modification of Base Flood Elevations (BFEs), base flood depths, Special Flood Hazard Area (SFHA) boundaries or...

  13. Analysis of the Tonle Sap Flood Pulse Based on Remote Sensing: how much does Tonle Sap Lake Affect the Mekong River Flood?

    Science.gov (United States)

    Qu, W.; Hu, N.; Fu, J.; Lu, J.; Lu, H.; Lei, T.; Pang, Z.; Li, X.; Li, L.

    2018-04-01

    The economic value of the Tonle Sap Lake Floodplain to Cambodia is among the highest provided to a nation by a single ecosystem around the world. The flow of Mekong River is the primary factor affecting the Tonle Sap Lake Floodplain. The Tonle Sap Lake also plays a very important role in regulating the downstream flood of Mekong River. Hence, it is necessary to understand its temporal changes of lake surface and water storage and to analyse its relation with the flood processes of Mekong River. Monthly lake surface and water storage from July 2013 to May 2014 were first monitored based on remote sensing data. The relationship between water surface and accumulative water storage change was then established. In combination with hydrological modelling results of Mekong River Basin, the relation between the lake's water storage and the runoff of Mekong River was analysed. It is found that the water storage has a sharp increase from September to December and, after reaching its maximum in December, water storage quickly decreases with a 38.8 billion m3 of drop in only half month time from December to January, while it keeps rather stable at a lower level in other months. There is a two months' time lag between the maximum lake water storage and the Mekong River peak flood, which shows the lake's huge flood regulation role to downstream Mekong River. It shows that this remote sensing approach is feasible and reliable in quantitative monitoring of data scarce lakes.

  14. Flood Disaster Mitigation as Revealed by Cawang-Manggarai River Improvement of Ciliwung River

    Directory of Open Access Journals (Sweden)

    Airlangga Mardjono

    2015-06-01

    The final result of this simulation shows that Scenario 3 gives the lowest water surface elevation profile. Scenario 3 is subjected to river normalization, revetment works along the river, and also flood control structure improvement through the additional sluice gate on Manggarai Barrage. This scenario results 167 cm, 163 cm, 172 cm, 179 cm, 167 cm and 171 cm or 17,60%, 17,16%, 18,09%, 18,76%, 17,38% and 17,72% of maximum water level reduction respectively over cross section number S 20 to S 25, for several simulations with 100 year of design discharge. Keywords: Simulation, river improvement, flood water surface elevation.

  15. Floods in Central Texas, September 7-14, 2010

    Science.gov (United States)

    Winters, Karl E.

    2012-01-01

    Severe flooding occurred near the Austin metropolitan area in central Texas September 7–14, 2010, because of heavy rainfall associated with Tropical Storm Hermine. The U.S. Geological Survey, in cooperation with the Upper Brushy Creek Water Control and Improvement District, determined rainfall amounts and annual exceedance probabilities for rainfall resulting in flooding in Bell, Williamson, and Travis counties in central Texas during September 2010. We documented peak streamflows and the annual exceedance probabilities for peak streamflows recorded at several streamflow-gaging stations in the study area. The 24-hour rainfall total exceeded 12 inches at some locations, with one report of 14.57 inches at Lake Georgetown. Rainfall probabilities were estimated using previously published depth-duration frequency maps for Texas. At 4 sites in Williamson County, the 24-hour rainfall had an annual exceedance probability of 0.002. Streamflow measurement data and flood-peak data from U.S. Geological Survey surface-water monitoring stations (streamflow and reservoir gaging stations) are presented, along with a comparison of September 2010 flood peaks to previous known maximums in the periods of record. Annual exceedance probabilities for peak streamflow were computed for 20 streamflow-gaging stations based on an analysis of streamflow-gaging station records. The annual exceedance probability was 0.03 for the September 2010 peak streamflow at the Geological Survey's streamflow-gaging stations 08104700 North Fork San Gabriel River near Georgetown, Texas, and 08154700 Bull Creek at Loop 360 near Austin, Texas. The annual exceedance probability was 0.02 for the peak streamflow for Geological Survey's streamflow-gaging station 08104500 Little River near Little River, Texas. The lack of similarity in the annual exceedance probabilities computed for precipitation and streamflow might be attributed to the small areal extent of the heaviest rainfall over these and the other gaged

  16. Quasi-continuous stochastic simulation framework for flood modelling

    Science.gov (United States)

    Moustakis, Yiannis; Kossieris, Panagiotis; Tsoukalas, Ioannis; Efstratiadis, Andreas

    2017-04-01

    Typically, flood modelling in the context of everyday engineering practices is addressed through event-based deterministic tools, e.g., the well-known SCS-CN method. A major shortcoming of such approaches is the ignorance of uncertainty, which is associated with the variability of soil moisture conditions and the variability of rainfall during the storm event.In event-based modeling, the sole expression of uncertainty is the return period of the design storm, which is assumed to represent the acceptable risk of all output quantities (flood volume, peak discharge, etc.). On the other hand, the varying antecedent soil moisture conditions across the basin are represented by means of scenarios (e.g., the three AMC types by SCS),while the temporal distribution of rainfall is represented through standard deterministic patterns (e.g., the alternative blocks method). In order to address these major inconsistencies,simultaneously preserving the simplicity and parsimony of the SCS-CN method, we have developed a quasi-continuous stochastic simulation approach, comprising the following steps: (1) generation of synthetic daily rainfall time series; (2) update of potential maximum soil moisture retention, on the basis of accumulated five-day rainfall; (3) estimation of daily runoff through the SCS-CN formula, using as inputs the daily rainfall and the updated value of soil moisture retention;(4) selection of extreme events and application of the standard SCS-CN procedure for each specific event, on the basis of synthetic rainfall.This scheme requires the use of two stochastic modelling components, namely the CastaliaR model, for the generation of synthetic daily data, and the HyetosMinute model, for the disaggregation of daily rainfall to finer temporal scales. Outcomes of this approach are a large number of synthetic flood events, allowing for expressing the design variables in statistical terms and thus properly evaluating the flood risk.

  17. Structural master plan of flood mitigation measures

    OpenAIRE

    A. Heidari

    2009-01-01

    Flood protection is one of the practical methods in damage reduction. Although it not possible to be completely protected from flood disaster but major part of damages can be reduced by mitigation plans. In this paper, the optimum flood mitigation master plan is determined by economic evaluation in trading off between the construction costs and expected value of damage reduction as the benefits. Size of the certain mitigation alternative is also be obtained by risk analysis by accepting possi...

  18. Flood Response System—A Case Study

    OpenAIRE

    Yogesh Kumar Singh; Upasana Dutta; T. S. Murugesh Prabhu; I. Prabu; Jitendra Mhatre; Manoj Khare; Sandeep Srivastava; Subasisha Dutta

    2017-01-01

    Flood Response System (FRS) is a network-enabled solution developed using open-source software. The system has query based flood damage assessment modules with outputs in the form of spatial maps and statistical databases. FRS effectively facilitates the management of post-disaster activities caused due to flood, like displaying spatial maps of area affected, inundated roads, etc., and maintains a steady flow of information at all levels with different access rights depending upon the critica...

  19. Peak Discharge, Flood Profile, Flood Inundation, and Debris Movement Accompanying the Failure of the Upper Reservoir at the Taum Sauk Pump Storage Facility near Lesterville, Missouri

    Science.gov (United States)

    Rydlund, Jr., Paul H.

    2006-01-01

    The Taum Sauk pump-storage hydroelectric power plant located in Reynolds County, Missouri, uses turbines that operate as pumps and hydraulic head generated by discharging water from an upper to a lower reservoir to produce electricity. A 55-acre upper reservoir with a 1.5- billion gallon capacity was built on top of Proffit Mountain, approximately 760 feet above the floodplain of the East Fork Black River. At approximately 5:16 am on December 14, 2005, a 680-foot wide section of the upper reservoir embankment failed suddenly, sending water rushing down the western side of Proffit Mountain and emptying into the floodplain of East Fork Black River. Flood waters from the upper reservoir flowed downstream through Johnson's Shut-Ins State Park and into the lower reservoir of the East Fork Black River. Floods such as this present unique challenges and opportunities to analyze and document peak-flow characteristics, flood profiles, inundation extents, and debris movement. On December 16, 2005, Light Detection and Ranging (LiDAR) data were collected and used to support hydraulic analyses, forensic failure analyses, damage extent, and mitigation of future disasters. To evaluate the impact of sedimentation in the lower reservoir, a bathymetric survey conducted on December 22 and 23, 2005, was compared to a previous bathymetric survey conducted in April, 2005. Survey results indicated the maximum reservoir capacity difference of 147 acre-feet existed at a pool elevation of 730 feet. Peak discharge estimates of 289,000 cubic feet per second along Proffit Mountain and 95,000 cubic feet per second along the East Fork Black River were determined through indirect measurement techniques. The magnitude of the embankment failure flood along the East Fork Black River was approximately 4 times greater than the 100-year flood frequency estimate of 21,900 cubic feet per second, and approximately 3 times greater than the 500-year flood frequency estimate of 30,500 cubic feet per second

  20. Influences on flood frequency distributions in Irish river catchments

    Directory of Open Access Journals (Sweden)

    S. Ahilan

    2012-04-01

    Full Text Available This study explores influences on flood frequency distributions in Irish rivers. A Generalised Extreme Value (GEV type I distribution is recommended in Ireland for estimating flood quantiles in a single site flood frequency analysis. This paper presents the findings of an investigation that identified the GEV statistical distributions that best fit the annual maximum (AM data series extracted from 172 gauging stations of 126 rivers in Ireland. Analysis of these data was undertaken to explore hydraulic and hydro-geological factors that influence flood frequency distributions. A hierarchical approach of increasing statistical power that used probability plots, moment and L-moment diagrams, the Hosking goodness of fit algorithm and a modified Anderson-Darling (A-D statistical test was followed to determine whether a type I, type II or type III distribution was valid. Results of the Hosking et al. method indicated that of the 143 stations with flow records exceeding 25 yr, data for 95 (67% was best represented by GEV type I distributions and a further 9 (6% and 39 (27% stations followed type II and type III distributions respectively. Type I, type II and type III distributions were determined for 83 (58%, 16 (11% and 34 (24% stations respectively using the modified A-D method (data from 10 stations was not represented by GEV family distributions. The influence of karst terrain on these flood frequency distributions was assessed by incorporating results on an Arc-GIS platform showing karst features and using Monte Carlo simulations to assess the significance of the number and clustering of the observed distributions. Floodplain effects were identified by using two-sample t-tests to identify statistical correlations between the distributions and catchment properties that are indicative of strong floodplain activity. The data reveals that type I distributions are spatially well represented throughout the country. While also well represented throughout

  1. Dam-breach analysis and flood-inundation mapping for Lakes Ellsworth and Lawtonka near Lawton, Oklahoma

    Science.gov (United States)

    Rendon, Samuel H.; Ashworth, Chad E.; Smith, S. Jerrod

    2012-01-01

    Dams provide beneficial functions such as flood control, recreation, and reliable water supplies, but they also entail risk: dam breaches and resultant floods can cause substantial property damage and loss of life. The State of Oklahoma requires each owner of a high-hazard dam, which the Federal Emergency Management Agency defines as dams for which failure or misoperation probably will cause loss of human life, to develop an emergency action plan specific to that dam. Components of an emergency action plan are to simulate a flood resulting from a possible dam breach and map the resulting downstream flood-inundation areas. The resulting flood-inundation maps can provide valuable information to city officials, emergency managers, and local residents for planning the emergency response if a dam breach occurs. Accurate topographic data are vital for developing flood-inundation maps. This report presents results of a cooperative study by the city of Lawton, Oklahoma, and the U.S. Geological Survey (USGS) to model dam-breach scenarios at Lakes Ellsworth and Lawtonka near Lawton and to map the potential flood-inundation areas of such dam breaches. To assist the city of Lawton with completion of the emergency action plans for Lakes Ellsworth and Lawtonka Dams, the USGS collected light detection and ranging (lidar) data that were used to develop a high-resolution digital elevation model and a 1-foot contour elevation map for the flood plains downstream from Lakes Ellsworth and Lawtonka. This digital elevation model and field measurements, streamflow-gaging station data (USGS streamflow-gaging station 07311000, East Cache Creek near Walters, Okla.), and hydraulic values were used as inputs for the dynamic (unsteady-flow) model, Hydrologic Engineering Center's River Analysis System (HEC-RAS). The modeled flood elevations were exported to a geographic information system to produce flood-inundation maps. Water-surface profiles were developed for a 75-percent probable maximum

  2. Reconstruction of the 1945 Wieringermeer Flood

    Science.gov (United States)

    Hoes, O. A. C.; Hut, R. W.; van de Giesen, N. C.; Boomgaard, M.

    2013-03-01

    The present state-of-the-art in flood risk assessment focuses on breach models, flood propagation models, and economic modelling of flood damage. However, models need to be validated with real data to avoid erroneous conclusions. Such reference data can either be historic data, or can be obtained from controlled experiments. The inundation of the Wieringermeer polder in the Netherlands in April 1945 is one of the few examples for which sufficient historical information is available. The objective of this article is to compare the flood simulation with flood data from 1945. The context, the breach growth process and the flood propagation are explained. Key findings for current flood risk management addresses the importance of the drainage canal network during the inundation of a polder, and the uncertainty that follows from not knowing the breach growth parameters. This case study shows that historical floods provide valuable data for the validation of models and reveal lessons that are applicable in current day flood risk management.

  3. Lessons Learned from Southeast Asian Floods

    Science.gov (United States)

    Osti, R.; Tanaka, S.

    2009-04-01

    At certain scales, flood has always been the lifeline of many people from Southeast Asian countries. People are traditionally accustomed to living with such floods and their livelihood is adjusted accordingly to optimize the benefits from the floods. However, large scale flood occasionally turns into the disaster and causes massive destruction not only in terms of human causalities but also damage to economic, ecological and social harmonies in the region. Although economic growth is prevailing in a relative term, the capacity of people to cope with such extreme events is weakening therefore the flood disaster risk is increasing in time. Recent examples of flood disaster in the region clearly show the increasing severity of disaster impact. This study reveals that there are many factors, which directly or indirectly influence the change. This paper considers the most prominent natural and socio-economic factors and analyzes their trend with respect to flood disasters in each country's context. A regional scale comparative analysis further helps to exchange the know how and to determine what kind of strategy and policy are lacking to manage the floods in a long run. It is also helpful in identifying the critical sectors that should be addressed first to mitigate the potential damage from the floods.

  4. Flood Response System—A Case Study

    Directory of Open Access Journals (Sweden)

    Yogesh Kumar Singh

    2017-06-01

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

  5. Polders as active element of flood control

    International Nuclear Information System (INIS)

    Zilavy, M.

    2004-01-01

    In this presentation author deals with use of the polders as active element of flood control on the example Kysuca River and Podluzianka River (Slovakia). It was concluded that it is necessary: - dense network of rain gauge stations; - network of water level recorders; revision of design process for hydraulic objects - degree of safety; changes in legislation - permission for construction in flood-plains; maintenance of channel capacity; early flood forecasting - forecasting and warning service; river training works and maintenance; design of retention areas; preparation of retention areas prior to flood propagation

  6. After the flood is before the next flood - post event review of the Central European Floods of June 2013. Insights, recommendations and next steps for future flood prevention

    Science.gov (United States)

    Szoenyi, Michael; Mechler, Reinhard; McCallum, Ian

    2015-04-01

    In early June 2013, severe flooding hit Central and Eastern Europe, causing extensive damage, in particular along the Danube and Elbe main watersheds. The situation was particularly severe in Eastern Germany, Austria, Hungary and the Czech Republic. Based on the Post Event Review Capability (PERC) approach, developed by Zurich Insurance's Flood Resilience Program to provide independent review of large flood events, we examine what has worked well (best practice) and opportunities for further improvement. The PERC overall aims to thoroughly examine aspects of flood resilience, flood risk management and catastrophe intervention in order to help build back better after events and learn for future events. As our research from post event analyses shows a lot of losses are in fact avoidable by taking the right measures pre-event and these measures are economically - efficient with a return of 4 Euro on losses saved for every Euro invested in prevention on average (Wharton/IIASA flood resilience alliance paper on cost benefit analysis, Mechler et al. 2014) and up to 10 Euros for certain countries. For the 2013 flood events we provide analysis on the following aspects and in general identify a number of factors that worked in terms of reducing the loss and risk burden. 1. Understanding risk factors of the Central European Floods 2013 We review the precursors leading up to the floods in June, with an extremely wet May 2013 and an atypical V-b weather pattern that brought immense precipitation in a very short period to the watersheds of Elbe, Donau and partially the Rhine in the D-A-CH countries and researched what happened during the flood and why. Key questions we asked revolve around which protection and risk reduction approaches worked well and which did not, and why. 2. Insights and recommendations from the post event review The PERC identified a number of risk factors, which need attention if risk is to be reduced over time. • Yet another "100-year flood" - risk

  7. Flood forecasting and warning systems in Pakistan

    International Nuclear Information System (INIS)

    Ali Awan, Shaukat

    2004-01-01

    Meteorologically, there are two situations which may cause three types of floods in Indus Basin in Pakistan: i) Meteorological Situation for Category-I Floods when the seasonal low is a semi permanent weather system situated over south eastern Balochistan, south western Punjab, adjoining parts of Sindh get intensified and causes the moisture from the Arabian Sea to be brought up to upper catchments of Chenab and Jhelum rivers. (ii) Meteorological Situation for Category-11 and Category-111 Floods, which is linked with monsoon low/depression. Such monsoon systems originate in Bay of Bengal region and then move across India in general west/north westerly direction arrive over Rajasthan or any of adjoining states of India. Flood management in Pakistan is multi-functional process involving a number of different organizations. The first step in the process is issuance of flood forecast/warning, which is performed by Pakistan Meteorological Department (PMD) utilizing satellite cloud pictures and quantitative precipitation measurement radar data, in addition to the conventional weather forecasting facilities. For quantitative flood forecasting, hydrological data is obtained through the Provincial Irrigation Department and WAPDA. Furthermore, improved rainfall/runoff and flood routing models have been developed to provide more reliable and explicit flood information to a flood prone population.(Author)

  8. Simulating Catchment Scale Afforestation for Mitigating Flooding

    Science.gov (United States)

    Barnes, M. S.; Bathurst, J. C.; Quinn, P. F.; Birkinshaw, S.

    2016-12-01

    After the 2013-14, and the more recent 2015-16, winter floods in the UK there were calls to 'forest the uplands' as a solution to reducing flood risk across the nation. However, the role of forests as a natural flood management practice remains highly controversial, due to a distinct lack of robust evidence into its effectiveness in reducing flood risk during extreme events. This project aims to improve the understanding of the impacts of upland afforestation on flood risk at the sub-catchment and full catchment scales. This will be achieved through an integrated fieldwork and modelling approach, with the use of a series of process based hydrological models to scale up and examine the effects forestry can have on flooding. Furthermore, there is a need to analyse the extent to which land management practices, catchment system engineering and the installation of runoff attenuation features (RAFs), such as engineered log jams, in headwater catchments can attenuate flood-wave movement, and potentially reduce downstream flood risk. Additionally, the proportion of a catchment or riparian reach that would need to be forested in order to achieve a significant impact on reducing downstream flooding will be defined. The consequential impacts of a corresponding reduction in agriculturally productive farmland and the potential decline of water resource availability will also be considered in order to safeguard the UK's food security and satisfy the global demand on water resources.

  9. Revealing the Maximum Strength in Nanotwinned Copper

    DEFF Research Database (Denmark)

    Lu, L.; Chen, X.; Huang, Xiaoxu

    2009-01-01

    boundary–related processes. We investigated the maximum strength of nanotwinned copper samples with different twin thicknesses. We found that the strength increases with decreasing twin thickness, reaching a maximum at 15 nanometers, followed by a softening at smaller values that is accompanied by enhanced...

  10. Modelling maximum canopy conductance and transpiration in ...

    African Journals Online (AJOL)

    There is much current interest in predicting the maximum amount of water that can be transpired by Eucalyptus trees. It is possible that industrial waste water may be applied as irrigation water to eucalypts and it is important to predict the maximum transpiration rates of these plantations in an attempt to dispose of this ...

  11. SURFACE FLOODS IN COIMBRA: simple and dual-drainage studies

    Science.gov (United States)

    Leitão, J. P.; Simões, N. E.; Pina, R.; Marques, A. Sá; Maksimović, Č.; Gonçalves, Gil

    2009-09-01

    flow along the roads towards the Praça 8 de Maio, which is the lowest point in the whole catchment and where water tends to accumulate. As presented in Table 1, the return periods calculated for durations shorter than 30 minutes are not high. In fact, this rainfall event is characterised by an extreme heavy intensity regarding its total duration; thus it cannot be considered a short period event with a high intensity. As its total duration is approximately the time of concentration of the catchment, the flooding event was very significant. A 50 year return period was estimated for the event with 45 minutes duration. Table 1: Return period interpretation of the 9 June 2006 rainfall event Duration 5 (min) 10 (min) 15 (min) 30 (min) 45 (min) Maximum rainfall intensity (mm/h)122.4 76.8 72.4 61.6 47.6 Return period1(year) 10 8 20 > 50 50 Comparing the simulation results and the actual flood locations, it is concluded that the main cause of flooding is not the capacity of the sewer system. Despite the high slopes and the high level of imperviousness of the catchment, the flood seems to be mainly caused due to the limited capacity of the sewer inlets. It suggests that the correct analysis of the hydraulic behaviour of the catchment drainage system should contemplate the analysis of the overland flow system, either using a one- (1D) or two-dimensional (2D) approaches. Hence, simulation of the 9 June 2006 event were also carried out considering the 1D sewer model, an 1D/1D model and an 1D/2D model. The methodology developed at the Imperial College London to generate overland flow networks was used in the 1D/1D model. Infoworks CS was used to do the hydraulic simulations of the 1D/1D and 1D/2D models. The results of the simulations taking into account the overland flow system will be presented in this paper. Local community reports and photos are then used to validate the simulation results obtained. Acknowledgements The authors would like to acknowledge Águas de Coimbra, E

  12. Operational flood forecasting, warning and response for multi-scale flood risks in developing cities

    NARCIS (Netherlands)

    Rogelis Prada, M.C.

    2016-01-01

    Flood early warning systems are recognized as one of the most effective flood risk management instruments when correctly embedded in comprehensive flood risk management strategies and policies. Many efforts around the world are being put in place to advance the components that determine the

  13. Do flood risk perceptions provide useful insights for flood risk management? Findings from central Vietnam

    NARCIS (Netherlands)

    Bubeck, P.; Botzen, W.J.W.; Suu, L.T.T.; Aerts, J.C.J.H.

    2012-01-01

    Following the renewed attention for non-structural flood risk reduction measures implemented at the household level, there has been an increased interest in individual flood risk perceptions. The reason for this is the commonly-made assumption that flood risk perceptions drive the motivation of

  14. 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

  15. Adaptation to flood risk: Results of international paired flood event studies

    NARCIS (Netherlands)

    Kreibich, Heidi; Di Baldassarre, G.; Vorogushyn, Sergiy; Aerts, J.C.J.H.; Apel, H.; Aronica, G.T.; Arnbjerg-Nielsen, K.; Bouwer, L.; Bubeck, P.; Caloiero, Tommaso; Chinh, Do. T.; Cortès, Maria; Gain, A.K.; Giampá, Vincenzo; Kuhlicke, C; Kundzewicz, Z.W.; Carmen Llasat, M; Mård, Johanna; Matczak, Piotr; Mazzoleni, Maurizio; Molinari, Daniela; Dung, N.V.; Petrucci, Olga; Schröter, Kai; Slager, Kymo; Thieken, A.H.; Ward, P.J.; Merz, B.

    2017-01-01

    As flood impacts are increasing in large parts of the world, understanding the primary drivers of changes in risk is essential for effective adaptation. To gain more knowledge on the basis of empirical case studies, we analyze eight paired floods, that is, consecutive flood events that occurred in

  16. Development of Integrated Flood Analysis System for Improving Flood Mitigation Capabilities in Korea

    Science.gov (United States)

    Moon, Young-Il; Kim, Jong-suk

    2016-04-01

    Recently, the needs of people are growing for a more safety life and secure homeland from unexpected natural disasters. Flood damages have been recorded every year and those damages are greater than the annual average of 2 trillion won since 2000 in Korea. It has been increased in casualties and property damages due to flooding caused by hydrometeorlogical extremes according to climate change. Although the importance of flooding situation is emerging rapidly, studies related to development of integrated management system for reducing floods are insufficient in Korea. In addition, it is difficult to effectively reduce floods without developing integrated operation system taking into account of sewage pipe network configuration with the river level. Since the floods result in increasing damages to infrastructure, as well as life and property, structural and non-structural measures should be urgently established in order to effectively reduce the flood. Therefore, in this study, we developed an integrated flood analysis system that systematized technology to quantify flood risk and flood forecasting for supporting synthetic decision-making through real-time monitoring and prediction on flash rain or short-term rainfall by using radar and satellite information in Korea. Keywords: Flooding, Integrated flood analysis system, Rainfall forecasting, Korea Acknowledgments This work was carried out with the support of "Cooperative Research Program for Agriculture Science & Technology Development (Project No. PJ011686022015)" Rural Development Administration, Republic of Korea

  17. Development of Probabilistic Flood Inundation Mapping For Flooding Induced by Dam Failure

    Science.gov (United States)

    Tsai, C.; Yeh, J. J. J.

    2017-12-01

    A primary function of flood inundation mapping is to forecast flood hazards and assess potential losses. However, uncertainties limit the reliability of inundation hazard assessments. Major sources of uncertainty should be taken into consideration by an optimal flood management strategy. This study focuses on the 20km reach downstream of the Shihmen Reservoir in Taiwan. A dam failure induced flood herein provides the upstream boundary conditions of flood routing. The two major sources of uncertainty that are considered in the hydraulic model and the flood inundation mapping herein are uncertainties in the dam break model and uncertainty of the roughness coefficient. The perturbance moment method is applied to a dam break model and the hydro system model to develop probabilistic flood inundation mapping. Various numbers of uncertain variables can be considered in these models and the variability of outputs can be quantified. The probabilistic flood inundation mapping for dam break induced floods can be developed with consideration of the variability of output using a commonly used HEC-RAS model. Different probabilistic flood inundation mappings are discussed and compared. Probabilistic flood inundation mappings are hoped to provide new physical insights in support of the evaluation of concerning reservoir flooded areas.

  18. “Expect More Floods In 2013”: An analysis of flood preparedness in ...

    African Journals Online (AJOL)

    In 2013, the Nigerian Meteorological Agency (NIMET) issued a prediction of heavy rainfall with consequent flooding in some major cities of Nigeria particularly Ibadan. In light of the country's previous flood experiences, citizens and government were promptly alerted and advised to be fully prepared for imminent floods.

  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. 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...

  1. A new modelling framework and mitigation measures for increased resilience to flooding

    Science.gov (United States)

    Valyrakis, Manousos; Alexakis, Athanasios; Solley, Mark

    2015-04-01

    Flooding in rivers and estuaries is amongst the most significant challenges our society has yet to tackle effectively. Use of floodwall systems is one of the potential measures that can be used to mitigate the detrimental socio-economical and ecological impacts and alleviate the associated costs of flooding. This work demonstrates the utility of such systems for a case study via appropriate numerical simulations, in addition to conducting scaled flume experiments towards obtaining a better understanding of the performance and efficiency of the flood-wall systems. At first, the results of several characteristic inundation modeling scenarios and flood mitigation options, for a flood-prone region in Scotland. In particular, the history and hydrology of the area are discussed and the assumptions and hydraulic model input (model geometry including instream hydraulic structures -such as bridges and weirs- river and floodplain roughness, initial and boundary conditions) are presented, followed by the model results. Emphasis is given on the potential improvements brought about by mitigating flood risk using flood-wall systems. Further, the implementation of the floodwall in mitigating flood risk is demonstrated via appropriate numerical modeling, utilizing HEC-RAS to simulate the effect of a river's rising stage during a flood event, for a specific area. The later part of this work involves the design, building and utilization of a scaled physical model of a flood-wall system. These experiments are carried out at one of the research flumes in the Water Engineering laboratory of the University of Glasgow. These involve an experimental investigation where the increase of force applied on the floodwall is measured for different degrees of deflection of the water in the stream, under the maximum flow discharge that can be carried through without exceeding the floodwall height (and accounting for the effect of super-elevation). These results can be considered upon the

  2. Zinc fertilization of flooded rice

    International Nuclear Information System (INIS)

    1981-02-01

    Local scientists studied Zn fertilization of flooded rice soils in Bangladesh, India, Indonesia, the Republic of Korea, Egypt, the Philippines, Thailand and Turkey. Diagnosis of Zn deficiency was carried out for submerged rice soils. Soil maps were prepared, designating areas as low, medium and high in Zn, based on Zn extraction with DTPA and HCl solutions and on rice leaf analysis. The effectiveness of various Zn fertilizer sources and methods of application in field and greenhouse experiments was measured, using 65 Zn. The percent Zn derived from fertilizer was shown to be a much more sensitive measure of efficiency than yield or total uptake

  3. Behaviour of suspended particulate matter (SPM and selected trace metals during the 2002 summer flood in the River Elbe (Germany at Magdeburg monitoring station

    Directory of Open Access Journals (Sweden)

    M. Baborowski

    2004-01-01

    Full Text Available In August 2002, in the worst flooding in more than 100 years, the River Elbe destroyed built-up areas and caused widespread erosion and the relocation of soils and river sediments. To assess the pollutants entering the water, surveys of dissolved constituents and suspended particulate matter (SPM were carried out daily during the flood at a monitoring station near Magdeburg. The sampling point is part of the network of the International Commission for the Protection of the Elbe (ICPE. The results were compared with those of previous flood studies which used the same sampling strategy. Unlike past floods, the 2002 flood was characterised by the transport of relatively fine suspended material with a low mass concentration. Owing to different input sources, the maxima of dry weight and of particle number concentration occurred at different times. Hg, Fe, Mn, Zn, Cu, Ni and Cr showed a maximum concentration concurrent with the dry weight of the SPM, whereas the maximum concentrations of As, Pb, and Cd coincided with the particle number concentration peak. The concentration of particulate matter decreased rapidly, unlike the concentrations of dissolved substances such as DOC and trace metals, as well as the values of UV extinction, all of which remained high for a longer period. Comparing the results of the 2002 flood with the winter floods in 1995, 1999 and 2000, revealed increased values of As and Pb as well as higher concentrations of dissolved compounds. Keywords: river, flood, transport, suspended particulate matter, trace metals, dissolved compounds, Elbe

  4. 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 ...

  5. 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...

  6. Social media for disaster response during floods

    Science.gov (United States)

    Eilander, D.; van de Vries, C.; Baart, F.; van Swol, R.; Wagemaker, J.; van Loenen, A.

    2015-12-01

    During floods it is difficult to obtain real-time accurate information about the extent and severity of the hazard. This information is very important for disaster risk reduction management and crisis relief organizations. Currently, real-time information is derived from few sources such as field reports, traffic camera's, satellite images and areal images. However, getting a real-time and accurate picture of the situation on the ground remains difficult. At the same time, people affected by natural hazards increasingly share their observations and their needs through digital media. Unlike conventional monitoring systems, Twitter data contains a relatively large number of real-time ground truth observations representing both physical hazard characteristics and hazard impacts. In the city of Jakarta, Indonesia, the intensity of unique flood related tweets during a flood event, peaked at almost 900 tweets per minute during floods in early 2015. Flood events around the world in 2014/2015 yielded large numbers of flood related tweets: from Philippines (85.000) to Pakistan (82.000) to South-Korea (50.000) to Detroit (20.000). The challenge here is to filter out useful content from this cloud of data, validate these observations and convert them to readily usable information. In Jakarta, flood related tweets often contain information about the flood depth. In a pilot we showed that this type of information can be used for real-time mapping of the flood extent by plotting these observations on a Digital Elevation Model. Uncertainties in the observations were taken into account by assigning a probability to each observation indicating its likelihood to be correct based on statistical analysis of the total population of tweets. The resulting flood maps proved to be correct for about 75% of the neighborhoods in Jakarta. Further cross-validation of flood related tweets against (hydro-) meteorological data is to likely improve the skill of the method.

  7. Hydrochemical aspects of the Aue pit flooding

    International Nuclear Information System (INIS)

    Meyer, J.; Jenk, U.; Schuppan, W.; Knappik, R.

    1998-01-01

    WISMUT is conducting controlled flooding of underground mines at the Schlema-Alberoda and Poehla sites. Flooding of the Poehla mine lasted from January 1992 through September 1995. Flooding at the Niederschlema-Alberoda site began in July 1990 and will continue to approximately 2002. In mid-1998 the flood level had reached the - 420 m level which is about 1,400 m above the lowest mine level. Only ground waters with low mineral and pollutant content are used for flooding purposes. Typically, the flooding process results in elevated levels of mineral salts and of uranium, radium, arsenic, iron, and manganese in flooding waters. However, the mobilised part of these contaminants represents only a small fraction of potential concentrations contained in the surrounding rock. Geochemical and hydrochemical conditions at both mines are characterised by the presence of carbonate buffers and by neutral pH and intermediate to low Eh. Decrease due to oxidation of sulphides in the long term is unlikely. Environmentally relevant metals in flooding waters may be dissolved, colloidal, or suspended solids with uranium present as uranyl carbonate complexes. Intensity of mobilisation is primarily a function of kinetic processes. Post flooding conditions at the Poehla subsite exhibit specific hydrochemical phenomena such as extremely reduced SO 4 concentrations and an increase in Ra concentrations over time. Continued flood monitoring will provide the basis for more in-depth interpretation and prognosis of contaminant mobilisation. Current investigations focus on technically feasible in situ control of mine flooding at the Schlema-Alberoda site to reduce contaminant mobilisation. At both sites water treatment plants are either on stream or under construction. (orig.)

  8. Flood mapping with multitemporal MODIS data

    Science.gov (United States)

    Son, Nguyen-Thanh; Chen, Chi-Farn; Chen, Cheng-Ru

    2014-05-01

    Flood is one of the most devastating and frequent disasters resulting in loss of human life and serve damage to infrastructure and agricultural production. Flood is phenomenal in the Mekong River Delta (MRD), Vietnam. It annually lasts from July to November. Information on spatiotemporal flood dynamics is thus important for planners to devise successful strategies for flood monitoring and mitigation of its negative effects. The main objective of this study is to develop an approach for weekly mapping flood dynamics with the Moderate Resolution Imaging Spectroradiometer data in MRD using the water fraction model (WFM). The data processed for 2009 comprises three main steps: (1) data pre-processing to construct smooth time series of the difference in the values (DVLE) between land surface water index (LSWI) and enhanced vegetation index (EVI) using the empirical mode decomposition (EMD), (2) flood derivation using WFM, and (3) accuracy assessment. The mapping results were compared with the ground reference data, which were constructed from Envisat Advanced Synthetic Aperture Radar (ASAR) data. As several error sources, including mixed-pixel problems and low-resolution bias between the mapping results and ground reference data, could lower the level of classification accuracy, the comparisons indicated satisfactory results with the overall accuracy of 80.5% and Kappa coefficient of 0.61, respectively. These results were reaffirmed by a close correlation between the MODIS-derived flood area and that of the ground reference map at the provincial level, with the correlation coefficients (R2) of 0.93. Considering the importance of remote sensing for monitoring floods and mitigating the damage caused by floods to crops and infrastructure, this study eventually leads to the realization of the value of using time-series MODIS DVLE data for weekly flood monitoring in MRD with the aid of EMD and WFM. Such an approach that could provide quantitative information on

  9. MXLKID: a maximum likelihood parameter identifier

    International Nuclear Information System (INIS)

    Gavel, D.T.

    1980-07-01

    MXLKID (MaXimum LiKelihood IDentifier) is a computer program designed to identify unknown parameters in a nonlinear dynamic system. Using noisy measurement data from the system, the maximum likelihood identifier computes a likelihood function (LF). Identification of system parameters is accomplished by maximizing the LF with respect to the parameters. The main body of this report briefly summarizes the maximum likelihood technique and gives instructions and examples for running the MXLKID program. MXLKID is implemented LRLTRAN on the CDC7600 computer at LLNL. A detailed mathematical description of the algorithm is given in the appendices. 24 figures, 6 tables

  10. Flooding

    Science.gov (United States)

    ... and soil contamination from burial. Typical methods of recycling and solid waste disposal in sanitary landfills often ... rid of standing water in rain gutters, old tires, buckets, plastic covers, toys, pools, or any other ...

  11. Development and comparision of techniques for estimating design basis flood flows for nuclear power plants

    International Nuclear Information System (INIS)

    1980-05-01

    Estimation of the design basis flood for Nuclear Power Plants can be carried out using either deterministic or stochastic techniques. Stochastic techniques, while widely used for the solution of a variety of hydrological and other problems, have not been used to date (1980) in connection with the estimation of design basis flood for NPP siting. This study compares the two techniques against one specific river site (Galt on the Grand River, Ontario). The study concludes that both techniques lead to comparable results , but that stochastic techniques have the advantage of extracting maximum information from available data and presenting the results (flood flow) as a continuous function of probability together with estimation of confidence limits. (author)

  12. RiverFlow2D numerical simulation of flood mitigation solutions in the Ebro River

    Directory of Open Access Journals (Sweden)

    I. Echeverribar

    2017-01-01

    Full Text Available A study of measures oriented to flood mitigation in the mid reach of the Ebro river is presented: elimination of vegetation in the riverbed, use of controlled flooding areas and construction or re-adaptation of levees. The software used is RiverFlow2D which solves the conservative free-surface flow equations with a finite volume method running on GPU. The results are compared with measurements at gauge stations and aerial views. The most effective measure has turned out to be the elimination of vegetation in the riverbed. It is demonstrated that not only the maximum flooded area is narrower but also it reduces the water depth up to 1 m. The other measures have local consequences when the peak discharge is relatively high although they could be useful in case the discharge is lower.

  13. Flood of February 1980 along the Agua Fria River, Maricopa County, Arizona

    Science.gov (United States)

    Thomsen, B.W.

    1980-01-01

    The flood of February 20, 1980, along the Agua Fria River below Waddell Dam, Maricopa County, Ariz., was caused by heavy rains during February 13-20. The runoff filled Lake Pleasant and resulted in the largest release--66,600 cubic feet per second--from the reservoir since it was built in 1927; the maximum inflow to the reservoir was about 73,300 cubic feet per second. The area inundated by the releases includes about 28 miles along the channel from the mouth of the Agua Fria River to the Beardsley Canal flume crossing 5 miles downstream from Waddell Dam. The flood of 1980 into Lake Pleasant has a recurrence interval of about 47 years, whereas the flood of record (1919) has a recurrence interval of about 100 years. (USGS)

  14. Comparison of regional index flood estimation procedures based on the extreme value type I distribution

    DEFF Research Database (Denmark)

    Kjeldsen, Thomas Rodding; Rosbjerg, Dan

    2002-01-01

    the prediction uncertainty and that the presence of intersite correlation tends to increase the uncertainty. A simulation study revealed that in regional index-flood estimation the method of probability weighted moments is preferable to method of moment estimation with regard to bias and RMSE.......A comparison of different methods for estimating T-year events is presented, all based on the Extreme Value Type I distribution. Series of annual maximum flood from ten gauging stations at the New Zealand South island have been used. Different methods of predicting the 100-year event...... and the connected uncertainty have been applied: At-site estimation and regional index-flood estimation with and without accounting for intersite correlation using either the method of moments or the method of probability weighted moments for parameter estimation. Furthermore, estimation at ungauged sites were...

  15. Flood early warning system: sensors and internet

    NARCIS (Netherlands)

    Pengel, B.E.; Krzhizhanovskaya, V.V.; Melnikova, N.B.; Shirshov, G.S.; Koelewijn, A.R.; Pyayt, A.L.; Mokhov, I.I.; Chavoshian, A.; Takeuchi, K.

    2013-01-01

    The UrbanFlood early warning system (EWS) is designed to monitor data from very large sensornetworks in flood defences such as embankments, dikes, levees, and dams. The EWS, based on the internet, uses real-time sensor information and Artificial Intelligence (AI) to immediately calculate the

  16. Stakeholder initiatives in flood risk management

    NARCIS (Netherlands)

    Edelenbos, Jurian; Buuren, Van Arwin; Roth, Dik; Winnubst, Madelinde

    2017-01-01

    In recent years stakeholder participation has become a popular topic in flood management. Little is known about how and under which circumstances local stakeholders initiate and develop successful flood management strategies and how governmental actors respond to them. Drawing on theories of

  17. 76 FR 58436 - Proposed Flood Elevation Determinations

    Science.gov (United States)

    2011-09-21

    ... +725 feet upstream of the U.S. Route 50 West exit ramp. Dickerson Creek Tributary 1......... At the... Flooding Approximately 1,025 None 2 Hawaii County. feet west of the intersection of Waikoloa Beach Drive... intersection of West Kawailani Street and Launa Street. Shallow Flooding Approximately 3.6 miles None 1 Hawaii...

  18. Survey of September 1987 Natal floods

    CSIR Research Space (South Africa)

    Badenhorst, P

    1989-01-01

    Full Text Available During the September 1987 floods in Natal various organisations collaborated by observing the effects of the floods. The efforts of the CSIR in Stellenbosch and Durban, and the Geology Departments of the Universities of Natal and Port Elizabeth were...

  19. Flooding Capability for River-based Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Curtis L. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Prescott, Steven [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ryan, Emerald [Idaho State Univ., Pocatello, ID (United States); Calhoun, Donna [Boise State Univ., ID (United States); Sampath, Ramprasad [Centroid Labs., Los Angeles, CA (United States); Anderson, S. Danielle [Idaho National Lab. (INL), Idaho Falls, ID (United States); Casteneda, Cody [Boise State Univ., ID (United States)

    2015-10-01

    This report describes the initial investigation into modeling and simulation tools for application of riverine flooding representation as part of the Risk-Informed Safety Margin Characterization (RISMC) Pathway external hazards evaluations. The report provides examples of different flooding conditions and scenarios that could impact river and watershed systems. Both 2D and 3D modeling approaches are described.

  20. Unstructured mesh adaptivity for urban flooding modelling

    Science.gov (United States)

    Hu, R.; Fang, F.; Salinas, P.; Pain, C. C.

    2018-05-01

    Over the past few decades, urban floods have been gaining more attention due to their increase in frequency. To provide reliable flooding predictions in urban areas, various numerical models have been developed to perform high-resolution flood simulations. However, the use of high-resolution meshes across the whole computational domain causes a high computational burden. In this paper, a 2D control-volume and finite-element flood model using adaptive unstructured mesh technology has been developed. This adaptive unstructured mesh technique enables meshes to be adapted optimally in time and space in response to the evolving flow features, thus providing sufficient mesh resolution where and when it is required. It has the advantage of capturing the details of local flows and wetting and drying front while reducing the computational cost. Complex topographic features are represented accurately during the flooding process. For example, the high-resolution meshes around the buildings and steep regions are placed when the flooding water reaches these regions. In this work a flooding event that happened in 2002 in Glasgow, Scotland, United Kingdom has been simulated to demonstrate the capability of the adaptive unstructured mesh flooding model. The simulations have been performed using both fixed and adaptive unstructured meshes, and then results have been compared with those published 2D and 3D results. The presented method shows that the 2D adaptive mesh model provides accurate results while having a low computational cost.

  1. 13 CFR 120.170 - Flood insurance.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Flood insurance. 120.170 Section 120.170 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Policies Applying to All Business Loans Requirements Imposed Under Other Laws and Orders § 120.170 Flood insurance...

  2. Flooding and its Effect on Trees

    Science.gov (United States)

    Stephen Bratkovich; Lisa Burban; Steven Katovich; Craig Locey; Jill Pokorny; Richard Wiest

    1993-01-01

    The 1993 floods along the Missouri and Mississippi Rivers and their tributaries have caused tremendous losses in terms of human life, homes, businesses and crop production. Bottomland areas have been under water for many weeks. Landowners, homeowners, foresters, park managers, and others are concerned about the long-term effect of the flooding on the forests of the...

  3. Freight economic vulnerabilities due to flooding events.

    Science.gov (United States)

    2016-12-01

    Extreme weather events, and flooding in particular, have been occurring more often and with increased severity over the past decade, and there is reason to expect this trend will continue in the future due to a changing climate. Flooding events can u...

  4. Managing flood risks in the Mekong Delta

    NARCIS (Netherlands)

    Hoang, Long Phi; Biesbroek, Robbert; Tri, Van Pham Dang; Kummu, Matti; Vliet, van Michelle T.H.; Leemans, Rik; Kabat, Pavel; Ludwig, Fulco

    2018-01-01

    Climate change and accelerating socioeconomic developments increasingly challenge flood-risk management in the Vietnamese Mekong River Delta—a typical large, economically dynamic and highly vulnerable delta. This study identifies and addresses the emerging challenges for flood-risk management.

  5. 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= .

  6. 77 FR 46994 - Proposed Flood Elevation Determinations

    Science.gov (United States)

    2012-08-07

    ..., it addresses the following flooding sources: Jones Bayou, Mississippi River, and Porter Bayou. DATES... Incorporated Areas'' addressed the following flooding sources: Jones Bayou, Mississippi River, and Porter Bayou.... Approximately 8.1 miles None +162 upstream of the Arkansas River confluence. Porter Bayou Approximately 0.8 mile...

  7. Impact of stream restoration on flood waves

    Science.gov (United States)

    Sholtes, J.; Doyle, M.

    2008-12-01

    Restoration of channelized or incised streams has the potential to reduce downstream flooding via storing and dissipating the energy of flood waves. Restoration design elements such as restoring meanders, reducing slope, restoring floodplain connectivity, re-introducing in-channel woody debris, and re-vegetating banks and the floodplain have the capacity to attenuate flood waves via energy dissipation and channel and floodplain storage. Flood discharge hydrographs measured up and downstream of several restored reaches of varying stream order and located in both urban and rural catchments are coupled with direct measurements of stream roughness at various stages to directly measure changes to peak discharge, flood wave celerity, and dispersion. A one-dimensional unsteady flow routing model, HEC-RAS, is calibrated and used to compare attenuation characteristics between pre and post restoration conditions. Modeled sensitivity results indicate that a restoration project placed on a smaller order stream demonstrates the highest relative reduction in peak discharge of routed flood waves compared to one of equal length on a higher order stream. Reductions in bed slope, extensions in channel length, and increases in channel and floodplain roughness follow restoration placement with the watershed in relative importance. By better understanding how design, scale, and location of restored reaches within a catchment hydraulically impact flood flows, this study contributes both to restoration design and site decision making. It also quantifies the effect of reach scale stream restoration on flood wave attenuation.

  8. 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.

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

    Science.gov (United States)

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

    2016-05-01

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

  10. 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...

  11. Maximum neutron flux in thermal reactors

    International Nuclear Information System (INIS)

    Strugar, P.V.

    1968-12-01

    Direct approach to the problem is to calculate spatial distribution of fuel concentration if the reactor core directly using the condition of maximum neutron flux and comply with thermal limitations. This paper proved that the problem can be solved by applying the variational calculus, i.e. by using the maximum principle of Pontryagin. Mathematical model of reactor core is based on the two-group neutron diffusion theory with some simplifications which make it appropriate from maximum principle point of view. Here applied theory of maximum principle are suitable for application. The solution of optimum distribution of fuel concentration in the reactor core is obtained in explicit analytical form. The reactor critical dimensions are roots of a system of nonlinear equations and verification of optimum conditions can be done only for specific examples

  12. Maximum allowable load on wheeled mobile manipulators

    International Nuclear Information System (INIS)

    Habibnejad Korayem, M.; Ghariblu, H.

    2003-01-01

    This paper develops a computational technique for finding the maximum allowable load of mobile manipulator during a given trajectory. The maximum allowable loads which can be achieved by a mobile manipulator during a given trajectory are limited by the number of factors; probably the dynamic properties of mobile base and mounted manipulator, their actuator limitations and additional constraints applied to resolving the redundancy are the most important factors. To resolve extra D.O.F introduced by the base mobility, additional constraint functions are proposed directly in the task space of mobile manipulator. Finally, in two numerical examples involving a two-link planar manipulator mounted on a differentially driven mobile base, application of the method to determining maximum allowable load is verified. The simulation results demonstrates the maximum allowable load on a desired trajectory has not a unique value and directly depends on the additional constraint functions which applies to resolve the motion redundancy

  13. Maximum phytoplankton concentrations in the sea

    DEFF Research Database (Denmark)

    Jackson, G.A.; Kiørboe, Thomas

    2008-01-01

    A simplification of plankton dynamics using coagulation theory provides predictions of the maximum algal concentration sustainable in aquatic systems. These predictions have previously been tested successfully against results from iron fertilization experiments. We extend the test to data collect...

  14. Effects of large floods on channel width: recent insights from Italian rivers

    Science.gov (United States)

    Scorpio, Vittoria; Righini, Margherita; Amponsah, William; Crema, Stefano; Ciccarese, Giuseppe; Nardi, Laura; Zoccatelli, Davide; Borga, Marco; Cavalli, Marco; Comiti, Francesco; Corsini, Alessandro; Marchi, Lorenzo; Rinaldi, Massimo; Surian, Nicola

    2017-04-01

    Variations of channel morphology occurring during large flood events (recurrence interval > 50-100 years.) are very often the cause of damages to buildings and infrastructures, as well as of casualties. However, our knowledge of such processes remains poor, as is our capability to predict them. Post-event campaigns documenting channel changes and linking them to hydrological and morphological factors thus bear an enormous value for both the scientific community and river management agencies. We present the results of an analysis on the geomorphic response associated to 4 large floods that occurred between October 2011 and September 2015, affecting several catchments in Northern Italy (Magra-Vara, Trebbia, Nure rivers) and Sardinia (Posada and Mannu di Bitti rivers), characterized by different climatic, lithological and geomorphological settings. The analysis considered more than 400 channel reaches characterized by a drainage area ranging from 39 to 1,100 km2 and featuring a wide range of lateral confinement, mostly within the partly- and unconfined conditions. The approach to flood analysis encompassed: (i) hydrological and hydraulic analysis; (ii) analysis of sediment delivery by landslides to the channel network; (iii) GIS-based and field assessment of morphological channel modifications. For the Nure River flood event (September 2015) a quantitative assessment on average bed level variations was also carried out. Return period for maximum hourly rainfall intensities and peak water discharges exceeded in all basins 100 yr, in some cases even 300 yr. Very high unit peak discharges were estimated, reaching 8.8 m3 s-1km-2 in the Nure River (205 km2) and up to 30 m3 s-1km-2in few Magra River tributaries (5-10 km2). Notable channel widening (post-flood width / pre-flood width > 1.1) occurred in 83% of studied reaches, and it was found more relevant in the channels with narrower initial width, i.e. along the relatively steep tributaries. For these tributaries, the

  15. Chronological trends in maximum and minimum water flows of the Teesta River, Bangladesh, and its implications

    Directory of Open Access Journals (Sweden)

    Md. Sanaul H. Mondal

    2017-03-01

    Full Text Available Bangladesh shares a common border with India in the west, north and east and with Myanmar in the southeast. These borders cut across 57 rivers that discharge through Bangladesh into the Bay of Bengal in the south. The upstream courses of these rivers traverse India, China, Nepal and Bhutan. Transboundary flows are the important sources of water resources in Bangladesh. Among the 57 transboundary rivers, the Teesta is the fourth major river in Bangladesh after the Ganges, the Brahmaputra and the Meghna and Bangladesh occupies about 2071 km2 . The Teesta River floodplain in Bangladesh accounts for 14% of the total cropped area and 9.15 million people of the country. The objective of this study was to investigate trends in both maximum and minimum water flow at Kaunia and Dalia stations for the Teesta River and the coping strategies developed by the communities to adjust with uncertain flood situations. The flow characteristics of the Teesta were analysed by calculating monthly maximum and minimum water levels and discharges from 1985 to 2006. Discharge of the Teesta over the last 22 years has been decreasing. Extreme low-flow conditions were likely to occur more frequently after the implementation of the Gozoldoba Barrage by India. However, a very sharp decrease in peak flows was also observed albeit unexpected high discharge in 1988, 1989, 1991, 1997, 1999 and 2004 with some in between April and October. Onrush of water causes frequent flash floods, whereas decreasing flow leaves the areas dependent on the Teesta vulnerable to droughts. Both these extreme situations had a negative impact on the lives and livelihoods of people dependent on the Teesta. Over the years, people have developed several risk mitigation strategies to adjust with both natural and anthropogenic flood situations. This article proposed the concept of ‘MAXIN (maximum and minimum flows’ for river water justice for riparian land.

  16. Maximum-Likelihood Detection Of Noncoherent CPM

    Science.gov (United States)

    Divsalar, Dariush; Simon, Marvin K.

    1993-01-01

    Simplified detectors proposed for use in maximum-likelihood-sequence detection of symbols in alphabet of size M transmitted by uncoded, full-response continuous phase modulation over radio channel with additive white Gaussian noise. Structures of receivers derived from particular interpretation of maximum-likelihood metrics. Receivers include front ends, structures of which depends only on M, analogous to those in receivers of coherent CPM. Parts of receivers following front ends have structures, complexity of which would depend on N.

  17. Evaluating the atmospheric drivers leading to the December 2014 flood in Schleswig-Holstein, Germany

    Science.gov (United States)

    Schade, Nils H.

    2017-06-01

    Regional analyses of atmospheric conditions that may cause flooding of important transport infrastructure (railway tracks, highways/roads, rivers/channels) and subsequent adaptation measures are part of topic 1 of the network of experts initiated by the German Federal Ministry of Transport and Digital Infrastructure (BMVI). As an example case study, the December 2014 flood in Schleswig-Holstein, Germany, was investigated. Atmospheric conditions at the onset of the flood event are described and evaluated with respect to the general weather circulation, initial wetness, and event precipitation. Persistent, predominantly westerly general weather circulations (GWCs) directed several low-pressure systems over the North Sea to Schleswig-Holstein during December 2014, accompanied by prolonged rainfall and finally a strong precipitation event in southern Schleswig-Holstein, causing several inland gauges to exceed their, by then maximum, water levels. Results show that the antecedent precipitation index (API) is able to reflect the soil moisture conditions and, in combination with the maximum 3-day precipitation sum (R3d), to capture the two main drivers finally leading to the flood: (1) the initial wetness of north-western Schleswig-Holstein and (2) strong event precipitation in southern and eastern Schleswig-Holstein from 21 to 23 December; at the same time, both indices exceeded their respective 5-year return periods. Further, trend analyses show that both API and R3d have been increasing during recent years, while regional patterns match the north-eastward shift of cyclone pathways, leading to a higher risk of flooding in Schleswig-Holstein. Within the network of experts, investigations of these and further indices/drivers for earth system changes (e.g. wind surge and sea level rise) derived from observations, reanalyses, and regional climate model data are planned for all German coastal areas. Results can be expected to lead to improved adaptation measures to floods

  18. Characterization of remarkable floods in France, a transdisciplinary approach applied on generalized floods of January 1910

    Science.gov (United States)

    Boudou, Martin; Lang, Michel; Vinet, Freddy; Coeur, Denis

    2014-05-01

    The 2007 Flood Directive promotes the integration and valorization of historical and significant floods in flood risk management (Flood Directive Text, chapter II, and article 4). Taking into account extreme past floods analysis seems necessary in the mitigation process of vulnerability face to flooding risk. In France, this aspect of the Directive was carried out through the elaboration of Preliminary Flood Risk Assessment (PFRA) and the establishment of a 2000 floods list. From this first list, a sample of 176 floods, considered as remarkable has been selected. These floods were compiled in discussion with local authorities in charge of flood management (Lang et al., 2012) and have to be integrated in priority in local risk management policies. However, a consideration emerges about this classification: how a remarkable flood can be defined? According which criteria can it be considered as remarkable? To answer these questions, a methodology has been established by building an evaluation grid of remarkable floods in France. The primary objective of this grid is to analyze the remarkable flood's characteristics (hydrological and meteorological characteristics, sociological- political and economic impacts), and secondly to propose a classification of significant floods selected in the 2011 PFRA. To elaborate this evaluation grid, several issues had to be taken into account. First, the objective is to allow the comparison of events from various periods. These temporal disparities include the integration of various kinds of data and point out the importance of historical hydrology. It is possible to evaluate accurately the characteristics of recent floods by interpreting quantitative data (for example hydrological records. However, for floods that occurred before the 1960's it is necessary resorting to qualitative information such as written sources is necessary (Coeur, Lang, 2008). In a second part the evaluation grid requires equitable criteria in order not to

  19. Review of the flood risk management system in Germany after the major flood in 2013

    Directory of Open Access Journals (Sweden)

    Annegret H. Thieken

    2016-06-01

    Full Text Available Widespread flooding in June 2013 caused damage costs of €6 to 8 billion in Germany, and awoke many memories of the floods in August 2002, which resulted in total damage of €11.6 billion and hence was the most expensive natural hazard event in Germany up to now. The event of 2002 does, however, also mark a reorientation toward an integrated flood risk management system in Germany. Therefore, the flood of 2013 offered the opportunity to review how the measures that politics, administration, and civil society have implemented since 2002 helped to cope with the flood and what still needs to be done to achieve effective and more integrated flood risk management. The review highlights considerable improvements on many levels, in particular (1 an increased consideration of flood hazards in spatial planning and urban development, (2 comprehensive property-level mitigation and preparedness measures, (3 more effective flood warnings and improved coordination of disaster response, and (4 a more targeted maintenance of flood defense systems. In 2013, this led to more effective flood management and to a reduction of damage. Nevertheless, important aspects remain unclear and need to be clarified. This particularly holds for balanced and coordinated strategies for reducing and overcoming the impacts of flooding in large catchments, cross-border and interdisciplinary cooperation, the role of the general public in the different phases of flood risk management, as well as a transparent risk transfer system. Recurring flood events reveal that flood risk managem