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Sample records for river flood control

  1. FLOOD AND FLOOD CONTROL OF THE YELLOW RIVER

    Institute of Scientific and Technical Information of China (English)

    Wenxue LI; Huirang WANG; Yunqi SU; Naiqian JIANG; Yuanfeng ZHANG

    2002-01-01

    The Yellow River is the cradle of China. It had long been the center of politics, economics and culture of China in history. Large coverage flood disaster occurred frequently in the Yellow River basin and the losses were often heavy. Thus, the Yellow River is also considered as the serious hidden danger of China. Since the founding of new China, structural and non-structural systems of flood control have been established basically. Tremendous successes have been made on flood control. Into the 21century, flood control standard of the Lower Yellow River has been increased significantly with the operation of the Xiaolangdi Reservoir. However, problems of the Yellow River are complicated and the tasks for solving these problems are arduous. Particularly, the sedimentation problem can't be solved completely in the near future. The situation of "suspended river" and threat of flood will long exist.Therefore, supported by rapid social and economical development of the nation and relied on advanced technology, the flood control system shall be perfected. Meantime, study of the Yellow River shall be enhanced in order to better understand the flood, get with it and use it thus to reduce flood disaster.

  2. Flood risk control of dams and dykes in middle reach of Huaihe River

    Directory of Open Access Journals (Sweden)

    Zhen-kun MA

    2014-01-01

    Full Text Available Three stochastic mathematical models for calculation of the reservoir flood regulation process, river course flood release, and flood risk rate under flood control were established based on the theory of stochastic differential equations and features of flood control systems in the middle reach of the Huaihe River from Xixian to the Bengbu floodgate, comprehensively considering uncertain factors of hydrology, hydraulics, and engineering control. They were used to calculate the flood risk rate with flood regulation of five key reservoirs, including the Meishan, Xianghongdian, Nianyushan, Mozitan, and Foziling reservoirs in the middle reach of the Huaihe River under different flood frequencies, the flood risk rate with river course flood release under design and check floods for the trunk of the Huaihe River in conjunction with relevant flood storage areas, and the flood risk rate with operation of the Linhuaigang Project under design and check floods. The calculated results show that (1 the five reservoirs can withstand design floods, but the Xianghongdian and Foziling reservoirs will suffer overtopping accidents under check floods; (2 considering the service of flood storage areas under the design flood conditions of the Huaihe River, the mean flood risk rate with flood regulation of dykes and dams from Xixian to the Bengbu floodgate is about 0.2, and the trunk of the Huaihe River can generally withstand design floods; and (3 under a check flood with the flood return period of 1 000 years, the risk rate of overtopping accidents of the Linhuaigang Project is not larger than 0.15, indicating that it has a high flood regulation capacity. Through regulation and application of the flood control system of the Linhuigang Project, the Huaihe River Basin can withstand large floods, and the safety of the protected area can be ensured.

  3. Flood control and shrinkage in the Haihe River Mouth

    Institute of Scientific and Technical Information of China (English)

    胡世雄; 王兆印; 李行伟

    2001-01-01

    Because of overusing water resources in the upper and middle reaches of the Haihe Basin, less and less water flows to the river mouth. The Haihe River flow is cut off in most time of the seasons, sediment deposited in the river mouth channel is rarely scoured away, and many of the river mouth channels have been shrinking quickly. The discharge capacity of the channel is consequently reduced greatly, which results in more and more serious flood hazard. Many tide gates have been built for storing fresh water and preventing the salty and turbid water. The channel downstream of the gate is silting up and people have to dredge the channel every year before the flood season. This paper studies the laws of the siltation and strategies controlling channel shrinkage. The strategies are digger dredging, trailer dredging, scouring with pumping water or storing tidal water, building double guiding dikes and building a new gate. Comparison of various strategies is performed, suggesting the most effective strategy con

  4. 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.

  5. Snagging and Clearing for Flood Control, Snake River, Minnesota.

    Science.gov (United States)

    1979-07-01

    range from a high of 1080F to a low of -490F. Frost-free days, as observed at the University of Minnesota Experiment Station at Crookston, Minnesota...American plum, and black willow (Salix nigra). Further away from the river a shrub layer is present consisting of chokecherry, raspberry (Rubus strigosus...flood-prone areas or erection of emergency * flood protection. 6.04 The National Weather Service currently provides area officials and local news

  6. Flood control and loss estimation for paddy field at midstream of Chao Phraya River Basin, Thailand

    Science.gov (United States)

    Cham, T. C.; Mitani, Y.

    2015-09-01

    2011 Thailand flood has brought serious impact to downstream of Chao Phraya River Basin. The flood peak period started from August, 2011 to the end of October, 2011. This research focuses on midstream of Chao Phraya River Basin, which is Nakhon Sawan area includes confluence of Nan River and Yom River, also confluence of Ping River and Nan River. The main purpose of this research is to understand the flood generation, estimate the flood volume and loss of paddy field, also recommends applicable flood counter measurement to ease the flood condition at downstream of Chao Phraya River Basin. In order to understand the flood condition, post-analysis is conducted at Nakhon Sawan. The post-analysis consists of field survey to measure the flood marks remained and interview with residents to understand living condition during flood. The 2011 Thailand flood generation at midstream is simulated using coupling of 1D and 2D hydrodynamic model to understand the flood generation during flood peak period. It is calibrated and validated using flood marks measured and streamflow data received from Royal Irrigation Department (RID). Validation of results shows good agreement between simulated result and actual condition. Subsequently, 3 scenarios of flood control are simulated and Geographic Information System (GIS) is used to assess the spatial distribution of flood extent and reduction of loss estimation at paddy field. In addition, loss estimation for paddy field at midstream is evaluated using GIS with the calculated inundation depth. Results show the proposed flood control at midstream able to minimize 5% of the loss of paddy field in 26 provinces.

  7. Engineering Strategies on Flood Control in Middle Reach of Yangtze River, China

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Flood disaster has been a serious hidden danger since the ancient time. The essential cause for the fact that floods have not been eliminated for hundreds of years is that time-honored strategies do not suit the cases of flood prevention. In the view of geological environmental analyses of flood formation and from the synthesis of experiences gained in flood control in the past hundreds of years, sluggish draining of flood, silt sedimentation in channel and building levee blindly constitute the main cause of intractable flood for a long time in the middle reach of the Yangtze River.Draining away silt and water is the only way to stamping out flood disaster. Opening up artificial waterways for flood diversion, draining away the silt of channel into the polders, and storing the flood water are important engineering measures for the flood control and damage reduction.

  8. Water power and flood control of Colorado River below Green River, Utah

    Science.gov (United States)

    La Rue, Eugene Clyde; Work, Hubert; Grover, Nathan C.

    1925-01-01

    The purpose of this report is to present the facts regarding available water supply and all known dam sites on Colorado River between Cataract Canyon, Utah, and Parker, Ariz., and to show the relative value of these dam sites. To determine the relative value of the dam sites, a comprehensive plan of development for Colorado River below the mouth of Green River is presented that will provide for the maximum practicable utilization of the potential power, maximum preservation of water for irrigation, effective elimination of the flood menace, and adequate solution of the silt problem. This plan, which is preliminary and is offered by the writer to show the basis for his conclusions relative to flood control, irrigation, power development, and silt storage, contemplates the construction of 13 dams making available 3,383 feet of head for the development of power and a maximum of 42,000,000 acre-feet of storage capacity for the control of floods, equalization of flow, and storage of silt.

  9. Flow structures and sandbar dynamics in a canyon river during a controlled flood, Colorado River, Arizona

    Science.gov (United States)

    Wright, S.A.; Kaplinski, M.

    2011-01-01

    In canyon rivers, debris fan constrictions create rapids and downstream pools characterized by secondary flow structures that are closely linked to channel morphology. In this paper we describe detailed measurements of the three-dimensional flow structure and sandbar dynamics of two pools along the Colorado River in the Grand Canyon during a controlled flood release from Glen Canyon Dam. Results indicate that the pools are characterized by large lateral recirculation zones (eddies) resulting from flow separation downstream from the channel constrictions, as well as helical flow structures in the main channel and eddy. The lateral recirculation zones are low-velocity areas conducive to fine sediment deposition, particularly in the vicinity of the separation and reattachment points and are thus the dominant flow structures controlling sandbar dynamics. The helical flow structures also affect morphology but appear secondary in importance to the lateral eddies. During the controlled flood, sandbars in the separation and reattachment zones at both sites tended to build gradually during the rising limb and peak flow. Deposition in shallow water on the sandbars was accompanied by erosion in deeper water along the sandbar slope at the interface with the main channel. Erosion occurred via rapid mass failures as well as by gradual boundary shear stress driven processes. The flow structures and morphologic links at our study sites are similar to those identified in other river environments, in particular sharply curved meanders and channel confluences where the coexistence of lateral recirculation and helical flows has been documented. Copyright 2011 by the American Geophysical Union.

  10. Efficiency of sediment transport by flood and its control in the Lower Yellow River

    Institute of Scientific and Technical Information of China (English)

    NI; Jinren; LIU; Xiaoyong; LI; Tianhong; ZHAO; Yean; JIN; L

    2004-01-01

    This paper presents the characteristics of sediment transport by flood in the Lower Yellow River with the reach from Huayuankou to Gaocun, which is regarded as a typical braided pattern. The Artificial Neural Network Model on Water Use for Sediment Transport (WUST) by flood was established based on the measured data from 1980 to 1998. Consequently, simulations of controlling process of sediment transport by flood were made in terms of the control theory under different scenarios. According to the situation of sediment transport by flood in the Lower Yellow River, Open-Loop control system and feedback control system were adopted in system design. In the Open-Loop control system, numerical simulations were made to reveal the relationship between average discharge of flood and the WUST with varying sediment concentrations. The results demonstrate that sediment concentration has significant influence on the controlling process of flood flow to WUST. It is practical and efficient to control WUST if sediment concentration is less than 20 kg/m3. In the feedback control system, controlling processes of sediment concentration and flood discharge for sediment transport were simulated respectively under given conditions, and it was found that sediment transport process could be controlled completely by sediment concentration and discharge at the inlet of the reach from Huayuankou to Gaocun. Using the same method, controlling processes of sediment transport by flood in other reaches in the Lower Yellow River were also simulated. For the case of sediment concentration being 20 kg/m3, the optimized controlling discharge ranges from 2390 to 2900 m3/s in the lower reach of Huayuankou.This study is also of significance to flood control and flushing sediment in the Lower Yellow River with proper operation modes of Xiaolangdi Reservoir.

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

    Science.gov (United States)

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

    2009-08-01

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

  12. The Historical Flood Of July 2008 From Vaser River Basin, Romania. Causes, Effects And Flood Control Actions

    Directory of Open Access Journals (Sweden)

    Sima Andrei

    2015-10-01

    Full Text Available Floods is an experience perceived by society as unexpected, unexplainable and traumatizing and nowadays a threat to humanity more than ever. Among the natural phenomena which negatively affect human activities, floods are the ones which usually have the most significant consequences. The research, evaluations and statistics related to these phenomena do not reveal the drama and serious consequences that come with floods. It was proven that the increase of these extreme hydrological phenomena it is closely related to the anthropic activities from the area. Vaser basin is the most significant sub-basin of Vișeu river basin, contributing with 28% from the total flow of Vișeu river. Having a strong touristic and economic potential, the basin is often threatened by flash floods which usually have devastating effects. During July 2008 there was recorded the most significant flood from the history of hydrometric activity that led to substantial damage and death among locals. The present paper aims to analyze this historical flood, identifying the causes, effects, as well as the methods to control this extreme hydric phenomenon.

  13. Flood Control, Mississippi River at Prairie du Chien, Wisconsin.

    Science.gov (United States)

    1977-02-01

    The health and saftey of residents in the project area are potentially affected during major floods. A serious threat to life is always present...There has been one death directly related to flooding. Other threats to public health and safety are related to traffic congestion, contamination of food ...larger animals, a more diversified subsLstaOc, was L o.cJ bascd on the hunting of smaller mammals and gathering of local pi’int foods on a seasonal basis

  14. Colorado River Basin Hover Dam - Review of Flood Control Regulation.

    Science.gov (United States)

    1982-07-01

    Percichthyidae Striped bass 1ile sxiiis Pocilldae Mosquito fish Cainbusia affnus Sailfin mollie Poecilia latipin a Mexican mollie Poecila mexicana Salmonidae...Colorado River Basin Progress Report No. 8, 195 pp. Vitt, L.J. and R.D. Ohmart, 1978. Herpetofauna of the Lower Colorado River: Davis Dam to the

  15. Sediment trapping analysis of flood control reservoirs in Upstream Ciliwung River using SWAT Model

    Science.gov (United States)

    Rofiq Ginanjar, Mirwan; Putra, Santosa Sandy

    2017-06-01

    The plans of Sukamahi dam and Ciawi dam construction for Jakarta flood risk reduction purpose had been proposed as feasible solutions to be implemented. However, the risk of the dam outlets clogging, caused by the sediment, is important to be anticipated. The prediction of the max sediment concentration in the reservoir is crucial for the dam operation planning. It is important to avoid the flood outlet tunnel clogging. This paper present a hydrologic sediment budget model of The Upstream Ciliwung River Basin, with flood control dam existence scenarios. The model was constructed within SWAT (Soil and Water Assessment Tools) plugin and run inside the QGIS framework. The free hydrological data from CFSR, soil data from FAO, and topographical data from CGIAR-CSI were implemented as the model input. The model resulted the sediment concentration dynamics of the Sukamahi and Ciawi reservoirs, on some suspended sediment parameter ranges. The sediment trapping efficiency was also computed by different possible dam capacity alternatives. The research findings will give a scientific decision making base for the river authority, in term of flood control dam planning, especially in The Upstream Ciliwung River Basin.

  16. Snagging, Clearing, and Shelterbelt for Flood Control, Snake River, Minnesota.

    Science.gov (United States)

    1982-01-01

    Water Quality 8 Water Supply 8 Wildlife Resources 11 Fish 11 Mamals 11 Birds 11 Amphibians and Reptiles 12 Endangered Species 12 Vegetation 12 Land Use...relationships. It is important, especially in an area like the Snake River, to maintain and, if possible, to propagate these ecosystems that represent the...River bottoms rich in bird life, as evidenced by the large number of species that are known to use the area. Amphibians and Reptiles 2.21 The limited

  17. Abiotic & biotic responses of the Colorado River to controlled floods at Glen Canyon Dam, Arizona, USA

    Science.gov (United States)

    Korman, Josh; Melis, Ted; Kennedy, Theodore A.

    2012-01-01

    Closure of Glen Canyon Dam reduced sand supply to the Colorado River in Grand Canyon National Park by about 94% while its operation has also eroded the park's sandbar habitats. Three controlled floods released from the dam since 1995 suggest that sandbars might be rebuilt and maintained, but only if repeated floods are timed to follow tributary sand deliveries below the dam. Monitoring data show that sandbars are dynamic and that their erosion after bar building is positively related with mean daily discharge and negatively related with tributary sand production after controlled floods. The March 2008 flood affected non-native rainbow trout abundance in the Lees Ferry tailwater, which supports a blue ribbon fishery. Downstream trout dispersal from the tailwater results in negative competitive interactions and predation on endangered humpback chub. Early survival rates of age-0 trout increased more than fourfold following the 2008 flood, and twofold in 2009, relative to prior years (2006-2007). Hatch-date analysis indicated that early survival rates were much higher for cohorts that emerged about 2 months after the 2008 flood relative to cohorts that emerged earlier that year. The 2009 survival data suggest that tailwater habitat improvements persisted for at least a year, but apparently decreased in 2010. Increased early survival rates for trout coincided with the increased availability of higher quality drifting food items after the 2008 flood owing to an increase in midges and black flies, preferred food items of rainbow trout. Repeated floods from the dam might sustainably rebuild and maintain sandbars if released when new tributary sand is available below the tailwater. Spring flooding might also sustain increased trout abundance and benefit the tailwater fishery, but also be a potential risk to humpback chub in Grand Canyon.

  18. New Challcngcs and Opportunitics for Flood Control in the Huai Rivcr: Addressing a Changing River-Lake Relationship

    Institute of Scientific and Technical Information of China (English)

    ZHANG Min; XIA Jun; HONG Cheng

    2012-01-01

    This paper addresses the change of the river-lake relationship in the Huai River and its causes due to environmental change and human activities. A preliminary analysis is made from three aspects: (1) the natural geographical change particularly captured by the Yellow River, (2) water conservancy project construction, and (3) socioeconomic development in the Huai River Basin. Key problems of changes in this river-lake relationship and the Huai River flood control are tackled, involving flood control and disaster alleviation ability of the Basin, engineering and non-engineering measurements applied to flood control and disaster mitigation, and water governance for adaptive management. Research shows that the Huai River is a rather complex one due to its complex geography with a hybrid wet and dry climate zoon, and higher population density. With the alternation of the river-lake relationship and socioeconomic development in the region, new problems keep arising, imposing new requirements on its sustainable water management. Thus, understanding the Huai River is a long and gradually improving process, its future planning should keep absorbing new achievements of science and technology development, employing new technologies and methods, and gradually deepening our understanding of its fundamental principles. Water governance and adaptive water management will be new challenges and opportunities for the Basin in its river system change and flood control.

  19. The influence of controlled floods on fine sediment storage in debris fan-affected canyons of the Colorado River basin

    Science.gov (United States)

    Mueller, Erich R.; Grams, Paul E.; Schmidt, John C.; Hazel, Joseph E.; Alexander, Jason S.; Kaplinski, Matt

    2014-01-01

    Prior to the construction of large dams on the Green and Colorado Rivers, annual floods aggraded sandbars in lateral flow-recirculation eddies with fine sediment scoured from the bed and delivered from upstream. Flows greater than normal dam operations may be used to mimic this process in an attempt to increase time-averaged sandbar size. These controlled floods may rebuild sandbars, but sediment deficit conditions downstream from the dams restrict the frequency that controlled floods produce beneficial results. Here, we integrate complimentary, long-term monitoring data sets from the Colorado River in Marble and Grand Canyons downstream from Glen Canyon dam and the Green River in the Canyon of Lodore downstream from Flaming Gorge dam. Since the mid-1990s, several controlled floods have occurred in these canyon rivers. These controlled floods scour fine sediment from the bed and build sandbars in eddies, thus increasing channel relief. These changes are short-lived, however, as interflood dam operations erode sandbars within several months to years. Controlled flood response and interflood changes in bed elevation are more variable in Marble Canyon and Grand Canyon, likely reflecting more variable fine sediment supply and stronger transience in channel bed sediment storage. Despite these differences, neither system shows a trend in fine-sediment storage during the period in which controlled floods were monitored. These results demonstrate that controlled floods build eddy sandbars and increase channel relief for short interflood periods, and this response may be typical in other dam-influenced canyon rivers. The degree to which these features persist depends on the frequency of controlled floods, but careful consideration of sediment supply is necessary to avoid increasing the long-term sediment deficit.

  20. The influence of controlled floods on fine sediment storage in debris fan-affected canyons of the Colorado River basin

    Science.gov (United States)

    Mueller, Erich R.; Grams, Paul E.; Schmidt, John C.; Hazel, Joseph E.; Alexander, Jason S.; Kaplinski, Matt

    2014-12-01

    Prior to the construction of large dams on the Green and Colorado Rivers, annual floods aggraded sandbars in lateral flow-recirculation eddies with fine sediment scoured from the bed and delivered from upstream. Flows greater than normal dam operations may be used to mimic this process in an attempt to increase time-averaged sandbar size. These controlled floods may rebuild sandbars, but sediment deficit conditions downstream from the dams restrict the frequency that controlled floods produce beneficial results. Here, we integrate complimentary, long-term monitoring data sets from the Colorado River in Marble and Grand Canyons downstream from Glen Canyon dam and the Green River in the Canyon of Lodore downstream from Flaming Gorge dam. Since the mid-1990s, several controlled floods have occurred in these canyon rivers. These controlled floods scour fine sediment from the bed and build sandbars in eddies, thus increasing channel relief. These changes are short-lived, however, as interflood dam operations erode sandbars within several months to years. Controlled flood response and interflood changes in bed elevation are more variable in Marble Canyon and Grand Canyon, likely reflecting more variable fine sediment supply and stronger transience in channel bed sediment storage. Despite these differences, neither system shows a trend in fine-sediment storage during the period in which controlled floods were monitored. These results demonstrate that controlled floods build eddy sandbars and increase channel relief for short interflood periods, and this response may be typical in other dam-influenced canyon rivers. The degree to which these features persist depends on the frequency of controlled floods, but careful consideration of sediment supply is necessary to avoid increasing the long-term sediment deficit.

  1. Flooding on Elbe River

    Science.gov (United States)

    2002-01-01

    Heavy rains in Central Europe over the past few weeks have led to some of the worst flooding the region has witnessed in more than a century. The floods have killed more than 100 people in Germany, Russia, Austria, Hungary, and the Czech Republic and have led to as much as $20 billion in damage. This false-color image of the Elbe River and its tributaries was taken on August 20, 2002, by the Moderate Resolution Imaging Spectroradiometer (MODIS), flying aboard NASA's Terra satellite. The floodwaters that inundated Dresden, Germany, earlier this week have moved north. As can be seen, the river resembles a fairly large lake in the center of the image just south of the town of Wittenberg. Flooding was also bad further downriver in the towns of Maqgdeburge and Hitzacker. Roughly 20,000 people were evacuated from their homes in northern Germany. Fifty thousand troops, border police, and technical assistance workers were called in to combat the floods along with 100,000 volunteers. The floodwaters are not expected to badly affect Hamburg, which sits on the mouth of the river on the North Sea. Credit:Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

  2. Functional Rehabilitation of the "Soil Reservoir" in Degraded Soils to Control Floods in the Yangtze River Watershed

    Institute of Scientific and Technical Information of China (English)

    SHI Xue-Zheng; LIANG Yin; YU Dong-Sheng; PAN Xian-Zhang; E. D. WARNER; WANG Hong-Jie

    2004-01-01

    The reasons for the Yangtze River flood calamity in 1998 are briefly introduced. The authors believe that using a "soil reservoir" concept is an important means to help control flooding of the Yangtze River.A "soil reservoir" has a large potential storage capacity and its water can be rapidly "discharged" into the underground water in a timely fashion. The eroded, infertile soils of the Yangtze River Watershed are currently an obstacle to efficient operation of the "soil reservoir". The storage capacity of this "soil reservoir"has been severely hampered due to intensive soil erosion and the formation of soil crusts. Therefore, possible measures to control floods in the Yangtze River Watershed include: rehabilitating the vegetation to preserve soil and water on the eroded infertile soils, enhancing infiltration of the different soil types, and utilizing the large "soil reservoir" of the upper reaches of the Yangtze River.

  3. Effects of Flood Control Works Failure in the Missouri River Basin

    Science.gov (United States)

    2014-06-13

    hydrologist with the National Resources Conservation Service; Bill Lawrence, a hydrologist with the National Weather Service; and Darwin Ockerman, a...duration of flooding in the Missouri River basin occurred in Saint Charles , Missouri. The Missouri River at Saint Charles stayed at or above flood...that protect Saint Charles and Saint Louis Counties along the Missouri River as displayed in figure 7. These levees protect over 69,000 acres; most of

  4. Channel response to extreme floods: Insights on controlling factors from six mountain rivers in northern Apennines, Italy

    Science.gov (United States)

    Surian, Nicola; Righini, Margherita; Lucía, Ana; Nardi, Laura; Amponsah, William; Benvenuti, Marco; Borga, Marco; Cavalli, Marco; Comiti, Francesco; Marchi, Lorenzo; Rinaldi, Massimo; Viero, Alessia

    2016-11-01

    This work addresses the geomorphic response of mountain rivers to extreme floods, exploring the relationships between morphological changes and controlling factors. The research was conducted on six tributaries of the Magra River (northern Apennines, Italy) whose catchments were affected by an extreme flood (estimated recurrence interval > 100 years in most of the basins) on 25 October 2011. An integrated approach was deployed to study this flood, including (i) analysis of channel width changes by comparing aerial photographs taken before and after the flood, (ii) estimate of peak discharges in ungauged streams, (iii) detailed mapping of landslides and analysis of their connectivity with the channel network. Channel widening occurred in 35 reaches out of 39. In reaches with channel slope hydraulic variables alone are not sufficient to satisfactorily explain the channel response to extreme floods, and inclusion of other factors such as lateral confinement is needed to increase explanatory capability of regression models. Concerning hydraulic variables, this study showed that the degree of channel widening is more strongly related to unit stream power calculated based on pre-flood channel width than to cross-sectional stream power and to unit stream power calculated with post-flood channel width. This could suggest that most width changes occurred after the flood peak. Finally, in terms of hazard, it is crucial to document the type and magnitude of channel changes, to identify controlling factors, and most importantly, to develop tools enabling us to predict where major geomorphic changes occur during an extreme flood.

  5. The Effect of Geologic Structures on the Control of Floods in the Middle Yangtze River Valley

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    This paper discusses the role of geologic structures in the occurrence of floods and how to prevent flood in the middle reaches of the Yangtze River, and gives the author's suggestion that the Luoshan Qiakou be expanded and the land reclaimed from Dongting Lake be returned to the lake in compliance with the law of geology.

  6. Anthropogenic impact on flood-risk: a large-scale assessment for planning controlled inundation strategies along the River Po

    Science.gov (United States)

    Domeneghetti, Alessio; Castellarin, Attilio; Brath, Armando

    2013-04-01

    The European Flood Directive (2007/60/EC) has fostered the development of innovative and sustainable approaches and methodologies for flood-risk mitigation and management. Furthermore, concerning flood-risk mitigation, the increasing awareness of how the anthropogenic pressures (e.g. demographic and land-use dynamics, uncontrolled urban and industrial expansion on flood-prone area) could strongly increase potential flood damages and losses has triggered a paradigm shift from "defending the territory against flooding" (e.g. by means of levee system strengthening and heightening) to "living with floods" (e.g. promoting compatible land-uses or adopting controlled flooding strategies of areas located outside the main embankments). The assessment of how socio-economic dynamics may influence flood-risk represents a fundamental skill that should be considered for planning a sustainable industrial and urban development of flood-prone areas, reducing their vulnerability and therefore minimizing socio-economic and ecological losses due to large flood events. These aspects, which are of fundamental importance for Institutions and public bodies in charge of Flood Directive requirements, need to be considered through a holistic approach at river basin scale. This study focuses on the evaluation of large-scale flood-risk mitigation strategies for the middle-lower reach of River Po (~350km), the longest Italian river and the largest in terms of streamflow. Due to the social and economical importance of the Po River floodplain (almost 40% of the total national gross product results from this area), our study aims at investigating the potential of combining simplified vulnerability indices with a quasi-2D model for the definition of sustainable and robust flood-risk mitigation strategies. Referring to past (1954) and recent (2006) land-use data sets (e.g. CORINE) we propose simplified vulnerability indices for assessing potential flood-risk of industrial and urbanized flood prone

  7. Coupled hydrogeomorphic and woody-seedling responses to controlled flood releases in a dryland river

    Science.gov (United States)

    Wilcox, Andrew C.; Shafroth, Patrick B.

    2013-01-01

    Interactions among flow, geomorphic processes, and riparian vegetation can strongly influence both channel form and vegetation communities. To investigate such interactions, we took advantage of a series of dam-managed flood releases that were designed in part to maintain a native riparian woodland system on a sand-bed, dryland river, the Bill Williams River, Arizona, USA. Our resulting multiyear flow experiment examined differential mortality among native and nonnative riparian seedlings, associated flood hydraulics and geomorphic changes, and the temporal evolution of feedbacks among vegetation, channel form, and hydraulics. We found that floods produced geomorphic and vegetation responses that varied with distance downstream of a dam, with scour and associated seedling mortality closer to the dam and aggradation and burial-induced mortality in a downstream reach. We also observed significantly greater mortality among nonnative tamarisk (Tamarix) seedlings than among native willow (Salix gooddingii) seedlings, reflecting the greater first-year growth of willow relative to tamarisk. When vegetation was small early in our study period, the effects of vegetation on flood hydraulics and on mediating flood-induced channel change were minimal. Vegetation growth in subsequent years resulted in stronger feedbacks, such that vegetation's stabilizing effect on bars and its drag effect on flow progressively increased, muting the geomorphic effects of a larger flood release. These observations suggest that the effectiveness of floods in producing geomorphic and ecological changes varies not only as a function of flood magnitude and duration, but also of antecedent vegetation density and size.

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

    Science.gov (United States)

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

    2017-08-01

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

  9. Ecosystem ecology meets adaptive management: food web response to a controlled flood on the Colorado River, Glen Canyon

    Science.gov (United States)

    Cross, Wyatt F.; Baxter, Colden V.; Donner, Kevin C.; Rosi-Marshall, Emma J.; Kennedy, Theodore A.; Hall, Robert O.; Wellard Kelly, Holly A.; Rogers, R. Scott

    2011-01-01

    Large dams have been constructed on rivers to meet human demands for water, electricity, navigation, and recreation. As a consequence, flow and temperature regimes have been altered, strongly affecting river food webs and ecosystem processes. Experimental high-flow dam releases, i.e., controlled floods, have been implemented on the Colorado River, USA, in an effort to reestablish pulsed flood events, redistribute sediments, improve conditions for native fishes, and increase understanding of how dam operations affect physical and biological processes. We quantified secondary production and organic matter flows in the food web below Glen Canyon dam for two years prior and one year after an experimental controlled flood in March 2008. Invertebrate biomass and secondary production declined significantly following the flood (total biomass, 55% decline; total production, 56% decline), with most of the decline driven by reductions in two nonnative invertebrate taxa, Potamopyrgus antipodarum and Gammarus lacustris. Diatoms dominated the trophic basis of invertebrate production before and after the controlled flood, and the largest organic matter flows were from diatoms to the three most productive invertebrate taxa (P. antipodarum, G. lacustris, and Tubificida). In contrast to invertebrates, production of rainbow trout (Oncorhynchus mykiss) increased substantially (194%) following the flood, despite the large decline in total secondary production of the invertebrate assemblage. This counterintuitive result is reconciled by a post-flood increase in production and drift concentrations of select invertebrate prey (i.e., Chironomidae and Simuliidae) that supported a large proportion of trout production but had relatively low secondary production. In addition, interaction strengths, measured as species impact values, were strongest between rainbow trout and these two taxa before and after the flood, demonstrating that the dominant consumer—resource interactions were not

  10. 33 CFR 211.6 - Rights which may be granted by the Secretary of the Army in river and harbor and flood control...

    Science.gov (United States)

    2010-07-01

    ... the Secretary of the Army in river and harbor and flood control property. 211.6 Section 211.6... and flood control property. (a) Leases. (1) The Secretary of the Army is authorized, whenever he shall deem it to be advantageous to the Government, to lease such real property under the control of...

  11. 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.

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

    Science.gov (United States)

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

    2017-01-01

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

  13. Beaver dams, hydrological thresholds, and controlled floods as a management tool in a desert riverine ecosystem, Bill Williams River, Arizona

    Science.gov (United States)

    Andersen, D.C.; Shafroth, P.B.

    2010-01-01

    Beaver convert lotic stream habitat to lentic through dam construction, and the process is reversed when a flood or other event causes dam failure. We investigated both processes on a regulated Sonoran Desert stream, using the criterion that average current velocity is < 0.2 m s-1 in a lentic reach. We estimated temporal change in the lotic:lentic stream length ratio by relating beaver pond length (determined by the upstream lentic-lotic boundary position) to dam size, and coupling that to the dam-size frequency distribution and repeated censuses of dams along the 58-km river. The ratio fell from 19:1 when no beaver dams were present to < 3:1 after 7 years of flows favourable for beaver. We investigated the dam failure-flood intensity relationship in three independent trials (experimental floods) featuring peak discharge ranging from 37 to 65 m3 s-1. Major damage (breach ??? 3-m wide) occurred at ??? 20% of monitored dams (n = 7-86) and a similar or higher proportion was moderately damaged. We detected neither a relationship between dam size and damage level nor a flood discharge threshold for initiating major damage. Dam constituent materials appeared to control the probability of major damage at low (attenuated) flood magnitude. We conclude that environmental flows prescribed to sustain desert riparian forest will also reduce beaver-created lentic habitat in a non-linear manner determined by both beaver dam and flood attributes. Consideration of both desirable and undesirable consequences of ecological engineering by beaver is important when optimizing environmental flows to meet ecological and socioeconomic goals. ?? 2010 John Wiley & Sons, Ltd.

  14. Origin of Columbia River flood basalt controlled by propagating rupture of the Farallon slab.

    Science.gov (United States)

    Liu, Lijun; Stegman, Dave R

    2012-02-15

    The origin of the Steens-Columbia River (SCR) flood basalts, which is presumed to be the onset of Yellowstone volcanism, has remained controversial, with the proposed conceptual models involving either a mantle plume or back-arc processes. Recent tomographic inversions based on the USArray data reveal unprecedented detail of upper-mantle structures of the western USA and tightly constrain geodynamic models simulating Farallon subduction, which has been proposed to influence the Yellowstone volcanism. Here we show that the best-fitting geodynamic model depicts an episode of slab tearing about 17 million years ago under eastern Oregon, where an associated sub-slab asthenospheric upwelling thermally erodes the Farallon slab, leading to formation of a slab gap at shallow depth. Driven by a gradient of dynamic pressure, the tear ruptured quickly north and south and within about two million years covering a distance of around 900 kilometres along all of eastern Oregon and northern Nevada. This tear would be consistent with the occurrence of major volcanic dikes during the SCR-Northern Nevada Rift flood basalt event both in space and time. The model predicts a petrogenetic sequence for the flood basalt with sources of melt starting from the base of the slab, at first remelting oceanic lithosphere and then evolving upwards, ending with remelting of oceanic crust. Such a progression helps to reconcile the existing controversies on the interpretation of SCR geochemistry and the involvement of the putative Yellowstone plume. Our study suggests a new mechanism for the formation of large igneous provinces.

  15. Green-blue water in the city: quantification of impact of source control versus end-of-pipe solutions on sewer and river floods.

    Science.gov (United States)

    De Vleeschauwer, K; Weustenraad, J; Nolf, C; Wolfs, V; De Meulder, B; Shannon, K; Willems, P

    2014-01-01

    Urbanization and climate change trends put strong pressures on urban water systems. Temporal variations in rainfall, runoff and water availability increase, and need to be compensated for by innovative adaptation strategies. One of these is stormwater retention and infiltration in open and/or green spaces in the city (blue-green water integration). This study evaluated the efficiency of three adaptation strategies for the city of Turnhout in Belgium, namely source control as a result of blue-green water integration, retention basins located downstream of the stormwater sewers, and end-of-pipe solutions based on river flood control reservoirs. The efficiency of these options is quantified by the reduction in sewer and river flood frequencies and volumes, and sewer overflow volumes. This is done by means of long-term simulations (100-year rainfall simulations) using an integrated conceptual sewer-river model calibrated to full hydrodynamic sewer and river models. Results show that combining open, green zones in the city with stormwater retention and infiltration for only 1% of the total city runoff area would lead to a 30 to 50% reduction in sewer flood volumes for return periods in the range 10-100 years. This is due to the additional surface storage and infiltration and consequent reduction in urban runoff. However, the impact of this source control option on downstream river floods is limited. Stormwater retention downstream of the sewer system gives a strong reduction in peak discharges to the receiving river. However due to the difference in response time between the sewer and river systems, this does not lead to a strong reduction in river flood frequency. The paper shows the importance of improving the interface between urban design and water management, and between sewer and river flood management.

  16. 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.

  17. Evaluation method to floodwater amount of difficult control and utilization in flood season for hyperconcentration rivers and its application

    Science.gov (United States)

    Li, X.

    2013-05-01

    The severe soil erosion in the Chinese Loess Plateau has resulted in high sediment concentration in runoff, which can cause tremendous pressure to the development and utilization of regional floodwater resources as well as the regional flood control and disaster mitigation. The floodwater amount of difficult control and utilization in flood season (FADCUFS) is an important part of the available amount of surface water resources. It also has a critical role in the sustainable development of water resources, especially for those hyperconcentration rivers (HRs) in the Loess Plateau. The evaluation of FADCUFS for HRs is an important issue in the field of hydrology and water resources. However, the understandings of its connotation, evaluation method, and nature are limited. Combined engineering measures with non-engineering ones, the evaluation method of FADCUFS for HRs was presented based on the angles of water quantity and quality. The method divides the FADCUFS into two parts in terms of the flood control operation characteristics of reservoir in HR and the relationship between water resources utilization and sediment in runoff, respectively. One is the amount of difficult regulation-control floodwater (DRCF), and the other is the volume of difficult utilization floodwater (DUF). A case study of the Bajiazui Reservoir, located in the typical Jinghe River (the second tributary of the Chinese Yellow River with high sediment concentration) was performed. Three typical years, wet year (1988), average year (1986), and dry years (1995 and 2000), were employed. According to the daily optimal operation model of Bajiazui Reservoir, the DRCF occurs for only the wet year instead of the average and the dry years. There are four times of DRCF with the amount of 26.74 m3/s (July 14), 14.58 m3/s (August 5), 10.27 m3/s (August 9), and 1.23 m3/s (August 12) in 1988, respectively, with a total amount of 4.56 million m3. A certain close relationship exists between the amount of DRCF

  18. Lateral Flooding Associated to Wave Flood Generation on River Surface

    Science.gov (United States)

    Ramírez-Núñez, C.; Parrot, J.-F.

    2016-06-01

    This research provides a wave flood simulation using a high resolution LiDAR Digital Terrain Model. The simulation is based on the generation of waves of different amplitudes that modify the river level in such a way that water invades the adjacent areas. The proposed algorithm firstly reconstitutes the original river surface of the studied river section and then defines the percentage of water loss when the wave floods move downstream. This procedure was applied to a gently slope area in the lower basin of Coatzacoalcos river, Veracruz (Mexico) defining the successive areas where lateral flooding occurs on its downstream movement.

  19. Dajing River Basin Flood Control Planning in Yueqing%乐清市大荆溪流域防洪规划编制的探讨

    Institute of Scientific and Technical Information of China (English)

    林佳

    2013-01-01

      Dajing River Basin, one of the well-known fold-ravaged areas in Yueqing, suffers frequent flood disaster and serious urban water-logging because of its poor flood control capacity and weak infrastructure .According to the specific cause anal-ysis on flood disaster, hydro meteorology, geographical conditions and flood control engineering in Dajing River , the comprehensive flood control planning formulation is talked about in the article based on the factors as reservoir project , dyke building, stream dredging, pump-station construction, etc.And the total train of thought of flood control in Dajing River is also displayed, including planning target , planning standards, planning principles, engineering measures and non-engi-neering measures, which helps to improve the flood control capacity effectively in Dajing River Basin and to solve urban water-logging to a great extent.%  乐清市大荆溪流域洪涝灾害频繁,而基础设施防洪能力薄弱,城镇内涝严重,是乐清市有名的洪灾区。根据大荆溪洪涝灾害水文气象、地理环境、防洪工程等方面的具体成因,对大荆溪防洪规划的规划目标、规划标准、规划原则、规划工程措施及非工程措施提出了水库工程、堤防工程、溪流疏溪、泵站建设等具体的防洪规划编制思路,可有效提高大荆溪流域防洪能力及解决城镇内涝问题。

  20. Risk analysis and computation of flood control capacity for river levee%江河堤防防洪能力的风险分析

    Institute of Scientific and Technical Information of China (English)

    梁在潮; 李泰来

    2001-01-01

    The reliability of the flood control capacity of river levee canreflect the qu antitative relation between the designed maximum water level of flood control fo r the levee and the actual water level in flood season.The risk analysis of the flood control capacity for river levee is conducted by a stochastic variable method.The definition of reliability and the risk for flood control capacity,the mo del and computation method of risk analysis are given.And as an illustration,the risk levels of flood control capacity for some reaches are computed.%江河堤防防洪能力可靠度,反映了堤防最高防洪水位与来流洪水位之间的数量关系。采用随机变量的分析方法,对河道堤防的防洪能力进行风险分析,给出了河道防洪能力的可靠度和风险度的定义、风险计算模式和计算方法。并以实例计算了某河段防洪能力的风险度。

  1. A Report on Fish and Wildlife Resources in Relation to the Flood Control Plan for the Sny River and Tributaries in the Upper Mississippi River Basin

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The flood control plan for the Sny Biver and tributaries id proposed "by the Department of the Army, Corps of Engineers, to alleviate flood damages on Mississippi...

  2. The effect of controlled floods on decadal-scale changes in channel morphology and fine sediment storage in a debris-fan affected river canyon

    Science.gov (United States)

    Mueller, E. R.; Grams, P. E.; Schmidt, J. C.

    2013-12-01

    In 2011, a large magnitude flow release from Flaming Gorge Reservoir resulted in the third highest recorded discharge of the Green River downstream from Flaming Gorge Dam subsequent to its closure in 1963. Following this event, we made measurements of channel geometry, tracer gravel displacement, and sandbar sedimentology at four long-term monitoring reaches within the Canyon of Lodore in Dinosaur National Monument, Colorado. Here we integrate these data with nearly two decades of channel monitoring at these sites, encompassing five controlled floods, and providing a coarse resolution, but coherent, picture of channel response and changes in fine sediment storage in a canyon-bound river. We discuss these results in the context of long-term monitoring of controlled flood response along the Colorado River in Marble and Grand Canyons, Arizona. In Canyon of Lodore, moderate, short-duration controlled floods have had little effect on channel morphology or fine sediment storage. Alternatively, higher magnitude floods approaching the pre-dam mean annual flood, such as in 1999 and 2011, tended to be long duration and scoured fine sediment from the channel bed, in some places up to 5 m, while building eddy sandbars to within a meter of flood stage. This resulted in a net export of sediment from the monitored reaches. Between floods, eddy sand bars erode and the pools fill with fine sediment. We have observed only minor erosion or reworking of gravel bars and channel margin deposits stabilized by vegetation encroachment. The Green River in Canyon of Lodore is a scaled-down version of the Colorado River in debris fan-affected Marble and Grand Canyons. Both rivers now exist in varying degrees of sediment deficit due to upstream reservoirs. Coarse sediment from debris fans and hillslopes limits vertical incision and channel migration, focusing the post-dam geomorphic response to sediment imbalance on fine sediment located in eddy sandbars, pools, and channel margin deposits. In

  3. Can riverside seismic monitoring constrain temporal and spatial variations in bedload transport during a controlled flood of the Trinity River?

    Science.gov (United States)

    Glasgow, M. E.; Schmandt, B.; Gaeuman, D.

    2015-12-01

    To evaluate the utility of riverside seismic monitoring for constraining temporal and spatial variations in coarse bedload transport in gravel-bed rivers we collected seismic data during a dam-controlled flood of the Trinity River in northern California in May 2015. This field area was chosen because the Trinity River Restoration Project conducts extensive monitoring of water and sediment transport, and riverbed morphology to guide management of the river with the goal of improving salmon habitat. Four three component broadband seismometers were collocated with water discharge and bedload physical sampling sites along a ~30 km reach of the Trinity River downstream of the Lewiston Dam. Arrays with 10-80 cable-free vertical component geophones were also deployed at each of the four sites in order to constrain spatial variability and amplitude decay of seismic signals emanating from the river. Nominal inter-station spacing within the geophone arrays was ~30 m. The largest geophone array consisted of 83 nodes along a 700 m reach of the Trinity River with a gravel augmentation site at its upstream end. Initial analyses of the seismic data show that ground velocity power from averaged from ~7 - 90 Hz is correlated with discharge at all sites. The array at the gravel injection site shows greater high frequency (>30 Hz) power at the upstream end where gravel was injected during the release compared to ~300 m downstream, consistent with bedload transport providing a significant source of seismic energy in addition to water discharge. Declining seismic power during a ~3 day plateau at peak discharge when physical sampler data shows decreasing bedload flux provides a further indication that the seismic data are sensitive to bedload transport. We will use the array data to back-project the seismic signals in multiple frequency bands into the channel to create maps of the time-varying spatial intensity of seismic energy production. We hypothesize that the greatest seismic

  4. Effects of flood control and other reservoir operations on the water quality of the lower Roanoke River, North Carolina

    Science.gov (United States)

    Garcia, Ana Maria

    2012-01-01

    The Roanoke River is an important natural resource for North Carolina, Virginia, and the Nation. Flood plains of the lower Roanoke River, which extend from Roanoke Rapids Dam to Batchelor Bay near Albemarle Sound, support a large and diverse population of nesting birds, waterfowl, freshwater and anadromous fish, and other wildlife, including threatened and endangered species. The flow regime of the lower Roanoke River is affected by a number of factors, including flood-management operations at the upstream John H. Kerr Dam and Reservoir. A three-dimensional, numerical water-quality model was developed to explore links between upstream flows and downstream water quality, specifically in-stream dissolved-oxygen dynamics. Calibration of the hydrodynamics and dissolved-oxygen concentrations emphasized the effect that flood-plain drainage has on water and oxygen levels, especially at locations more than 40 kilometers away from the Roanoke Rapids Dam. Model hydrodynamics were calibrated at three locations on the lower Roanoke River, yielding coefficients of determination between 0.5 and 0.9. Dissolved-oxygen concentrations were calibrated at the same sites, and coefficients of determination ranged between 0.6 and 0.8. The model has been used to quantify relations among river flow, flood-plain water level, and in-stream dissolved-oxygen concentrations in support of management of operations of the John H. Kerr Dam, which affects overall flows in the lower Roanoke River. Scenarios have been developed to mitigate the negative effects that timing, duration, and extent of flood-plain inundation may have on vegetation, wildlife, and fisheries in the lower Roanoke River corridor. Under specific scenarios, the model predicted that mean dissolved-oxygen concentrations could be increased by 15 percent by flow-release schedules that minimize the drainage of anoxic flood-plain waters. The model provides a tool for water-quality managers that can help identify options that improve

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

    Science.gov (United States)

    Skelly, Klint T.

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

  6. 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.

  7. Minnesota River at Chaska, Minnesota, Flood Control. Final Environmental Impact Statement.

    Science.gov (United States)

    1975-07-01

    would divert flood waters into a bypass channel which would lead first to the east and then southward just west of the Gedney Pickle Factory. Water...Under disturbed conditions a variety of species is found such as the wild cucumber (Echinocystis lobata), an indicator of floodplain conditions in the...surrounding farmlands, and some objectionable odors are occasionally emitted from the Gedney pickle plant. SOLID WASTE Solid wastes generated in

  8. Mercury exports from a High-Arctic river basin in Northeast Greenland (74°N) largely controlled by glacial lake outburst floods.

    Science.gov (United States)

    Søndergaard, Jens; Tamstorf, Mikkel; Elberling, Bo; Larsen, Martin M; Mylius, Maria Rask; Lund, Magnus; Abermann, Jakob; Rigét, Frank

    2015-05-01

    Riverine mercury (Hg) export dynamics from the Zackenberg River Basin (ZRB) in Northeast Greenland were studied for the period 2009-2013. Dissolved and sediment-bound Hg was measured regularly in the Zackenberg River throughout the periods with running water (June-October) and coupled to water discharge measurements. Also, a few samples of snow, soil, and permafrost were analysed for Hg. Mean concentrations of dissolved and sediment-bound Hg in the river water (±SD) were 0.39 ± 0.13 and 5.5 ± 1.4 ngL(-1), respectively, and mean concentrations of Hg in the river sediment were 0.033 ± 0.025 mg kg(-1). Temporal variations in river Hg were mainly associated with snowmelt, sudden erosion events, and outburst floods from a glacier-dammed lake in the upper part of the ZRB. Annual Hg exports from the 514 km(2) ZRB varied from 0.71 to >1.57 kg and the majority (86-96%) was associated with sediment-bound Hg. Hg yields from the ZRB varied from 1.4-3.1 gH gk m(-2)yr(-1) and were among the highest yields reported from Arctic river basins. River exports of Hg from ZRB were found to be largely controlled by the frequency, magnitude and timing of the glacial lake outburst floods, which occurred in four of the five years in July-August. Floods accounted for 5 to >10% of the annual water discharge, and up to >31% of the annual Hg export. Also, the winter snowfall and the summer temperatures were found to be important indirect controls on the annual Hg export. The occurrence and timing of glacial lake outburst floods in the ZRB in late summer at the time of maximum soil thaw depth, the location of the glacier in the upper ZRB, and increased thawing of the permafrost in Zackenberg in recent years leading to destabilisation of river banks are considered central factors explaining the high fraction of flood-controlled Hg export in this area.

  9. Preliminary Study in Spatial Data Warehouse of Flood Control and Disaster Mitigation in Yangtze River Basin%长江防洪减灾空间数据仓库初步研究

    Institute of Scientific and Technical Information of China (English)

    詹小国

    2002-01-01

    Since 1990s,the spatial data warehouse technology has rapidly been developing, but due to the complexity of multi-dimensional analysis, extensive application of the spatial data warehouse technology is affected. In the light of the characteristics of the flood control and disaster mitigation in the Yangtze river basin, it is proposed to design a scheme about the subjects and data distribution of the spatial data warehouse of the flood control and disaster mitigation in Yangtze river basin, i.e., to adopt a distributed scheme. The creation and development of the spatial data warehouse of the flood control and disaster mitigation in Yangtze river basin is presented .The necessity and urgency of establishing the spatial data warehouse is expounded from the viewpoint of the present situation being short of available information for the flood control and disaster mitigation in Yangtze river basin.

  10. Flood Control Burlington Dam, Souris River, North Dakota. Final Environment Impact Statement.

    Science.gov (United States)

    1978-01-01

    Refuges (NWR’s), since the N4WR’s contain perhaps the key wildlife habitat along the Souris River, and since the NWR’s are of key environmental...are like Burlingtcr Dam in all the key characteristics. There are also no Puhlished res;icw articles which compare all these different conditions and...persisted for a few years since floodwater storage, is dominated by the thistles Sonchus and especially Cirsium, and appears rather stable and persistent

  11. The Bosna River floods in May 2014

    Science.gov (United States)

    Vidmar, Andrej; Globevnik, Lidija; Koprivšek, Maja; Sečnik, Matej; Zabret, Katarina; Đurović, Blažo; Anzeljc, Darko; Kastelic, Janez; Kobold, Mira; Sušnik, Mojca; Borojevič, Darko; Kupusović, Tarik; Kupusović, Esena; Vihar, Anja; Brilly, Mitja

    2016-10-01

    In May 2014, extreme floods occurred in the lower Sava River basin, causing major damage, with catastrophic consequences. Based on the data gathered, the weather situation in Bosnia and Herzegovina's (BiH) Bosna River basin was analysed and the hydrological conditions were provided, including the results of the probability analysis of the size of the recorded precipitation and flow rates. According to the observed data, extremely high precipitation intensities produced specific discharges of 1.0 m3 s-1 km-2. A hydrological model of the Bosna River basin was developed using HBV light for the purposes of reconstructing and forecasting such events more effectively. All analyses confirmed that the May 2014 event was an extreme extraordinary event whose return period greatly exceeds 100 years. The study is the basis for further flood safety measures and flood forecast development in the Bosna River basin.

  12. South Fork Zumbro River Stage 1B, Rochester, Minnesota. Design Memorandum Number 2, Flood Control Project

    Science.gov (United States)

    1987-02-01

    Softb AMuchy, lack G M S, Very Dense, Block /00 Bo. 970 =_ Loose, Black-Gray 001, Very Dense, Tan -Gray 20 Very SofC Block TeO of Bedrock 2 , •MI P/a...Env cae,•,+,"’ epd ~-TaP ay. Dwq. 86 -1034e /0 May 49S6 :WS 9743 1 Water I To- of Bedrok -970 3 A/oaes: J .960 I/ ..Fork Zunbro River eev. 974.3: 2. ft

  13. General Reevaluation and Environmental Impact Statement for Flood Control and Related Purposes, Sheyenne River, North Dakota

    Science.gov (United States)

    1984-01-01

    Commitments are required at all three levels to resolve the issues. Failure by any one of the levels will result in either complete failure of the plan...Human Serv. Denver, CO Advisory Council on Historic Pres. Washington, D.C. ND Coordinator, Custer NF Bismarck, ND Chief, River Basin Pin . Br...N f C it I It ■■j JU *1 C 4J C I f’-III I « • E u o ᝿" iSi*I!j ji jllIUi =J iifiSi si 2a » Sfr -8 5S «I

  14. Mercury exports from a High-Arctic river basin in Northeast Greenland (74°N) largely controlled by glacial lake outburst floods

    DEFF Research Database (Denmark)

    Søndergaard, Jens; Tamstorf, Mikkel P.; Elberling, Bo

    2015-01-01

    .025 mg kg(-1). Temporal variations in river Hg were mainly associated with snowmelt, sudden erosion events, and outburst floods from a glacier-dammed lake in the upper part of the ZRB. Annual Hg exports from the 514 km(2) ZRB varied from 0.71 to >1.57 kg and the majority (86-96 was associated...... with sediment-bound Hg. Hg yields from the ZRB varied from 1.4-3.1 g Hg km(-2) yr(-1) and were among the highest yields reported from Arctic river basins. River exports of Hg from ZRB were found to be largely controlled by the frequency, magnitude and timing of the glacial lake outburst floods, which occurred...... in four of the five years in July-August. Floods accounted for 5 to >10% of the annual water discharge, and up to >31% of the annual Hg export. Also, the winter snowfall and the summer temperatures were found to be important indirect controls on the annual Hg export. The occurrence and timing of glacial...

  15. Floods in the Skagit River basin, Washington

    Science.gov (United States)

    Stewart, James E.; Bodhaine, George Lawrence

    1961-01-01

    According to Indian tradition, floods of unusually great magnitude harassed the Skagit River basin about 1815 and 1856. The heights of these floods were not recorded at the time; so they are called historical floods. Since the arrival of white men about 1863, a number of large and damaging floods have been witnessed and recorded. Data concerning and verifying the early floods, including those of 1815 and 1856, were collected prior to 1923 by James E. Stewart. He talked with many of the early settlers in the valley who had listened to Indians tell about the terrible floods. Some of these settlers had referenced the maximum stages of floods they had witnessed by cutting notches at or measuring to high-water marks on trees. In order to verify flood stages Stewart spent many weeks finding and levelling to high-water marks such as drift deposits, sand layers in coves, and silt in the bark of certain types of trees. Gaging stations have been in operation at various locations on the Skagit River and its tributaries since 1909, so recorded peak stages are available at certain sites for floods occurring since that date. All peak discharge data available for both historical and recorded floods have been listed in this report. The types of floods as to winter and summer, the duration of peaks, and the effect of reservoirs are discussed. In 1899 Sterling Dam was constructed at the head of Gages Slough near Sedro Woolley. This was the beginning of major diking in the lower reaches of the Skagit River. Maps included in the report show the location of most of the dike failures that have occurred during the last 73 years and the area probably inundated by major floods. The damage resulting from certain floods is briefly discussed. The report is concluded with a brief discussion of the U.S. Geological Survey method of computing flood-frequency curves as applied to the Skagit River basin. The treatment of single-station records and a means of combining these records for expressing

  16. Comprehensive flood control involving citizens in a Japanese watershed.

    Science.gov (United States)

    Yamashita, Sampei; Shimatani, Yukihiro; Watanabe, Ryoichi; Moriyama, Toshiyuki; Minagawa, Tomoko; Kakudo, Kumiko; Yamashita, Terukazu

    2013-01-01

    In July 2009, the city of Fukuoka, Japan experienced a flood disaster along the Hii River, which runs through densely populated, concrete-covered areas of the city. The drainage system was overwhelmed and the river overflowed due to heavy rainfall and rapid runoff. The event led citizens in its watershed to plan and implement comprehensive flood control. The plan aims not only to mitigate floods but also to revitalize the river environment and populated communities in urban areas. This study reports the activities led by the citizens. They organized and carried out civic forums, workshops, and fieldwork to share views as to how the flood disaster was caused, how floods in the watershed should be controlled, and how the river environment should be rehabilitated. This study illuminates how people, including the flood victims and municipal engineers, can change drastically and communicate effectively in the course of discussing and implementing the comprehensive flood control measures.

  17. 对东苕溪“6·19”洪水防御案例的思考%"6. ]9" Flood Control of East Tiaoxi River

    Institute of Scientific and Technical Information of China (English)

    沈强勇; 沈宇翔; 汪建江

    2011-01-01

    基于余杭区东苕溪2011年成功防御“6·19”洪水实例,从洪水防御部署、科学调度、基层防汛体系等方面介绍防洪调度情况,并通过对洪水成因分析和洪水过程分析,总结洪水预报、洪水调度、水利工程和基层防汛队伍在防洪中起到的作用,提出进一步巩固东苕溪洪水防御工作和进一步,提高东苕溪流域防洪防台抗旱能力的思路.%The causes of "6.19" Flood is analyzed in the article and the experience in flood defense is also summed up in several aspects, such as flood prevention deployment, scientific control, and primary flood control system. The further flood control measures is introduced based on the flood explananon and process analysis in East Tiaoxi River, mainly in flood forecasting, flood scheduling, water conservancy engineering and flood prevention institutions, in order to improve flood control and drought-proof capacity of East Tiaoxi River.

  18. Lake Darling Flood Control Project, Souris River, North Dakota. General Project Design.

    Science.gov (United States)

    1983-06-01

    el. 1607.0 * F iti Grano Crossing (FAS 3828) raise to el. 1607.0 Lake Darling Dam Crossing provide bridge over spillway Other roads misc...Relocation 10 - Grano Crossing 11 - Soo Line Railroad Relocation 12 - Renville Co. Park Levee 13 - McKinney Cemetery Levee 14 - Eckert Ranch 15 - Upper Souris... Grano Crossing. At State Highway 5, the 100-year profile, plus freeboard for wave action, is the controlling criteria, which requires 2.5 feet over the

  19. Global drivers of future river flood risk

    Science.gov (United States)

    Winsemius, Hessel C.; Aerts, Jeroen C. J. H.; van Beek, Ludovicus P. H.; Bierkens, Marc F. P.; Bouwman, Arno; Jongman, Brenden; Kwadijk, Jaap C. J.; Ligtvoet, Willem; Lucas, Paul L.; van Vuuren, Detlef P.; Ward, Philip J.

    2016-04-01

    Understanding global future river flood risk is a prerequisite for the quantification of climate change impacts and planning effective adaptation strategies. Existing global flood risk projections fail to integrate the combined dynamics of expected socio-economic development and climate change. We present the first global future river flood risk projections that separate the impacts of climate change and socio-economic development. The projections are based on an ensemble of climate model outputs, socio-economic scenarios, and a state-of-the-art hydrologic river flood model combined with socio-economic impact models. Globally, absolute damage may increase by up to a factor of 20 by the end of the century without action. Countries in Southeast Asia face a severe increase in flood risk. Although climate change contributes significantly to the increase in risk in Southeast Asia, we show that it is dwarfed by the effect of socio-economic growth, even after normalization for gross domestic product (GDP) growth. African countries face a strong increase in risk mainly due to socio-economic change. However, when normalized to GDP, climate change becomes by far the strongest driver. Both high- and low-income countries may benefit greatly from investing in adaptation measures, for which our analysis provides a basis.

  20. Increasing river floods: fiction or reality?

    Science.gov (United States)

    Blöschl, Günter; Gaál, Ladislav; Hall, Julia; Kiss, Andrea; Komma, Jürgen; Nester, Thomas; Parajka, Juraj; Perdigão, Rui A P; Plavcová, Lenka; Rogger, Magdalena; Salinas, José Luis; Viglione, Alberto

    2015-01-01

    There has been a surprisingly large number of major floods in the last years around the world, which suggests that floods may have increased and will continue to increase in the next decades. However, the realism of such changes is still hotly discussed in the literature. This overview article examines whether floods have changed in the past and explores the driving processes of such changes in the atmosphere, the catchments and the river system based on examples from Europe. Methods are reviewed for assessing whether floods may increase in the future. Accounting for feedbacks within the human-water system is important when assessing flood changes over lead times of decades or centuries. It is argued that an integrated flood risk management approach is needed for dealing with future flood risk with a focus on reducing the vulnerability of the societal system. WIREs Water 2015, 2:329-344. doi: 10.1002/wat2.1079 For further resources related to this article, please visit the WIREs website.

  1. 《玛纳斯河防洪规划》对新疆洪水灾害防御的启示%《Xinjiang Manasi River Flood Control Plan》 has significant enlightenment effect on prevention and control of flood in Xinjiang

    Institute of Scientific and Technical Information of China (English)

    鲁爱阳; 党新成; 周冰

    2011-01-01

    由新疆水电设计院完成的《新疆玛纳斯河防洪规划》,较全面的对玛纳斯河洪水成因,防洪整体方案,洪水计算,防洪标准等进行了全面的规划论证。对玛河防洪起到了重要的指导作用,对全疆中小河流有借鉴作用,对全疆洪水灾害防御有启示意义。%The "Xinjiang Manasi River Flood Control Plan", which was designed and performed by Xinjiang Hydro- power Design Institute, comprehensively demonstrated about the cause of flood, the overall solutions, flood computation, the flood control standards, etc. It has played an important instructional role on Manasi River flood control, which can be the reference for medium and small rivers in Xinjiang, and has significant enlightenment effect on prevention and control of flood in Xinjiang.

  2. 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...

  3. Effects of fluctuating flows and a controlled flood on incubation success and early survival rates and growth of age-0 rainbow trout in a large regulated river

    Science.gov (United States)

    Korman, Josh; Kaplinski, Matthew; Melis, Theodore S.

    2011-01-01

    Hourly fluctuations in flow from Glen Canyon Dam were increased in an attempt to limit the population of nonnative rainbow trout Oncorhynchus mykiss in the Colorado River, Arizona, due to concerns about negative effects of nonnative trout on endangered native fishes. Controlled floods have also been conducted to enhance native fish habitat. We estimated that rainbow trout incubation mortality rates resulting from greater fluctuations in flow were 23-49% (2003 and 2004) compared with 5-11% under normal flow fluctuations (2006-2010). Effects of this mortality were apparent in redd excavations but were not seen in hatch date distributions or in the abundance of the age-0 population. Multiple lines of evidence indicated that a controlled flood in March 2008, which was intended to enhance native fish habitat, resulted in a large increase in early survival rates of age-0 rainbow trout. Age-0 abundance in July 2008 was over fourfold higher than expected given the number of viable eggs that produced these fish. A hatch date analysis indicated that early survival rates were much higher for cohorts that hatched about 1 month after the controlled flood (~April 15) relative to those that hatched before this date. The cohorts that were fertilized after the flood were not exposed to high flows and emerged into better-quality habitat with elevated food availability. Interannual differences in age-0 rainbow trout growth based on otolith microstructure supported this hypothesis. It is likely that strong compensation in survival rates shortly after emergence mitigated the impact of incubation losses caused by increases in flow fluctuations. Control of nonnative fish populations will be most effective when additional mortality is applied to older life stages after the majority of density-dependent mortality has occurred. Our study highlights the need to rigorously assess instream flow decisions through the evaluation of population-level responses.

  4. Correcting acoustic Doppler current profiler discharge measurement bias from moving-bed conditions without global positioning during the 2004 Glen Canyon Dam controlled flood on the Colorado River

    Science.gov (United States)

    Gartner, J.W.; Ganju, N.K.

    2007-01-01

    Discharge measurements were made by acoustic Doppler current profiler at two locations on the Colorado River during the 2004 controlled flood from Glen Canyon Dam, Arizona. Measurement hardware and software have constantly improved from the 1980s such that discharge measurements by acoustic profiling instruments are now routinely made over a wide range of hydrologic conditions. However, measurements made with instruments deployed from moving boats require reliable boat velocity data for accurate measurements of discharge. This is normally accomplished by using special acoustic bottom track pings that sense instrument motion over bottom. While this method is suitable for most conditions, high current flows that produce downstream bed sediment movement create a condition known as moving bed that will bias velocities and discharge to lower than actual values. When this situation exists, one solution is to determine boat velocity with satellite positioning information. Another solution is to use a lower frequency instrument. Discharge measurements made during the 2004 Glen Canyon controlled flood were subject to moving-bed conditions and frequent loss of bottom track. Due to site conditions and equipment availability, the measurements were conducted without benefit of external positioning information or lower frequency instruments. This paper documents and evaluates several techniques used to correct the resulting underestimated discharge measurements. One technique produces discharge values in good agreement with estimates from numerical model and measured hydrographs during the flood. ?? 2007, by the American Society of Limnology and Oceanography, Inc.

  5. An urban flood in the kashio river basin

    OpenAIRE

    Matsuda, Iware

    1987-01-01

    An urban flood is one of knotty problems derived from land development. Taking the Kashio River basin of Kanagawa Prefecture as an example, the relationships between urbanization and flood hazards were historically discussed. It was explained that a flood prevention work in one area affects other areas. The historical change in conditions for flood hazards can be divided into six stages.

  6. Geomorphic adjustment to hydrologic modifications along a meandering river: Implications for surface flooding on a floodplain

    Science.gov (United States)

    Edwards, Brandon L.; Keim, Richard F.; Johnson, Erin L.; Hupp, Cliff R.; Marre, Saraline; King, Sammy L.

    2016-09-01

    Responses of large regulated rivers to contemporary changes in base level are not well understood. We used field measurements and historical analysis of air photos and topographic maps to identify geomorphic trends of the lower White River, Arkansas, USA, in the 70 years following base-level lowering at its confluence with the Mississippi River and concurrent with flood control by dams. Incision was identified below a knickpoint area upstream of St. Charles, AR, and increases over the lowermost ~90 km of the study site to ~2 m near the confluence with the Mississippi River. Mean bankfull width increased by 30 m (21%) from 1930 to 2010. Bank widening appears to be the result of flow regulation above the incision knickpoint and concomitant with incision below the knickpoint. Hydraulic modeling indicated that geomorphic adjustments likely reduced flooding by 58% during frequent floods in the incised, lowermost floodplain affected by backwater flooding from the Mississippi River and by 22% above the knickpoint area. Dominance of backwater flooding in the incised reach indicates that incision is more important than flood control on the lower White River in altering flooding and also suggests that the Mississippi River may be the dominant control in shaping the lower floodplain. Overall, results highlight the complex geomorphic adjustment in large river-floodplain systems in response to anthropogenic modifications and their implications, including reduced river-floodplain connectivity.

  7. Study on joint flood control operation for leading reservoirs in the upper Changjiang River%长江流域上游控制性水库群联合防洪调度研究

    Institute of Scientific and Technical Information of China (English)

    李安强; 张建云; 仲志余; 丁毅

    2013-01-01

      长江流域水系复杂,防洪对象分布范围广,控制性水库的防洪调度目标具有多元化、分布多区域特征,如何科学运用水库防洪库容,有序兼顾各区域防洪是流域控制性水库群联合防洪调度的关键。选取溪洛渡、向家坝与三峡水库组成的水库群为对象,基于大系统分解协调原理,先通过逐次分解各防洪区域对溪洛渡、向家坝两库预留防洪库容的要求,在结合区域间洪水遭遇关联性分析的基础上,提出两库防洪库容在协调川江与长江中下游两区域防洪中的分配方案;同时对三峡水库的防洪调度方式深入优化,提出适当扩大对城陵矶防洪补偿库容分配方案。研究成果表明,联合调度方案可进一步减少长江中下游分洪量,对于提高整个流域防洪减灾水平,完善长江流域库群防洪调度体系具有重要意义。%The Changjiang River possesses a complex river system and widely distributed flood protection objects. As the multi-nurpose of flood control operation for its leading reservoirs involving a wide range of regions, the key for joint flood control operation of leading reservoirs in the river basin lies on utilizing flood control storage reasonably and orderly giving consideration to overall plans flood control for related re⁃gions. Taking a group of reservoirs, Xiluodu, Xiangjiaba and the Three Gorges as the object, this paper proposes flood control storage allocation plan for coordinative flood control of the Chuanjiang and the Changjiang rivers by using the principle of large-scale system decomposition-coordination, through succes⁃sively decomposing the different demands for the flood control storage of Xiluodu and Xiangjiaba reservoirs by the flood protection objects in every region,and analyzing flood strike patterns for the Chuanjiang River and the midstream of the Changjiang River. Further, a flood control operation mode of the Three Gorges

  8. 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

  9. A Large-Scale Experiment to Determine the Effectiveness of Controlled Floods and Tamarisk Removal in Rehabilitating the Green River, Dinosaur National Monument, Colorado

    Science.gov (United States)

    Schmidt, J. C.; Cooper, D. J.; Larson, G. P.

    2002-12-01

    A large-scale field experiment is underway on the Green River in the Canyon of Lodore to evaluate the effectiveness of tamarisk (Tamarix ramosissima) removal and increased magnitude and duration of floods released from Flaming Gorge Dam (FGD) for the purpose of increasing active channel width and increasing entrainment rates on gravel bars where there are large proportions of fines. Results to date demonstrate that effectiveness varies with small scale geomorphic setting, and that channel widening in some parts of the river may be impossible without regular removal, which is unlikely. Our approach is important in channel rehabilitation planning, yet the difficulties of conducting such experiments are apparent in the first 2 yrs of the project. All tamarisk are being removed in 3, 0.8 to 1.6 km long study reaches. Three control reaches, immediately upstream or downstream from removal reaches, are also being monitored. We are making detailed measurements of scour and fill, substrate, and composition of riparian vegetation communities in removal and control reaches, and in response to high flood releases from FGD. Difficulties in implementation of the experiment include the multi-year process of tamarisk removal. Tamarisk immediately reestablishes itself on moist substrate following removal; thus, some parts of removal reaches have young tamarisk seedlings and other parts have tamarisk not yet removed. Experimental dam releases have not yet occurred due to drought in the watershed and other water delivery imperatives. We have also compared the distribution of tamarisk on the nearby Yampa River, where an unregulated flow regime exists and where tamarisk are absent or in low densities. The comparison between the distribution, density, and age characteristics of tamarisk on the 2 streams will lead to recommendations as to the sites on the Green River where eradication efforts are best directed. Despite the difficulties of experiment implementation, such large

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

    Science.gov (United States)

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

    2016-04-01

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

  11. Lithologic and hydrologic controls of mixed alluvial-bedrock channels in flood-prone fluvial systems: Bankfull and macrochannels in the Llano River watershed, central Texas, USA

    Science.gov (United States)

    Heitmuller, Franklin T.; Hudson, Paul F.; Asquith, William H.

    2015-03-01

    The rural and unregulated Llano River watershed located in central Texas, USA, has a highly variable flow regime and a wide range of instantaneous peak flows. Abrupt transitions in surface lithology exist along the main-stem channel course. Both of these characteristics afford an opportunity to examine hydrologic, lithologic, and sedimentary controls on downstream changes in channel morphology. Field surveys of channel topography and boundary composition are coupled with sediment analyses, hydraulic computations, flood-frequency analyses, and geographic information system mapping to discern controls on channel geometry (profile, pattern, and shape) and dimensions along the mixed alluvial-bedrock Llano River and key tributaries. Four categories of channel classification in a downstream direction include: (i) uppermost ephemeral reaches, (ii) straight or sinuous gravel-bed channels in Cretaceous carbonate sedimentary zones, (iii) straight or sinuous gravel-bed or bedrock channels in Paleozoic sedimentary zones, and (iv) straight, braided, or multithread mixed alluvial-bedrock channels with sandy beds in Precambrian igneous and metamorphic zones. Principal findings include: (i) a nearly linear channel profile attributed to resistant bedrock incision checkpoints; (ii) statistically significant correlations of both alluvial sinuosity and valley confinement to relatively high f (mean depth) hydraulic geometry values; (iii) relatively high b (width) hydraulic geometry values in partly confined settings with sinuous channels upstream from a prominent incision checkpoint; (iv) different functional flow categories including frequently occurring events (excess of 200 watts per square meter (W/m2); and (vi) downstream convergence of hydraulic geometry exponents for bankfull and macrochannels, explained by co-increases of flood magnitude and noncohesive sandy sediments that collectively minimize development of alluvial bankfull indicators. Collectively, these findings indicate

  12. Two-dimensional Model of Ciliwung River Flood in DKI Jakarta for Development of the Regional Flood Index Map

    Directory of Open Access Journals (Sweden)

    Adam Formánek

    2013-12-01

    Full Text Available The objective of this study was to present a sophisticated method of developing supporting material for flood control implementation in DKI Jakarta. High flow rates in the Ciliwung River flowing through Jakarta regularly causes extensive flooding in the rainy season. The affected area comprises highly densely populated villages. For developing an efficient early warning system in view of decreasing the vulnerability of the locations a flood index map has to be available. This study analyses the development of a flood risk map of the inundation area based on a two-dimensional modeling using FESWMS. The reference event used for the model was the most recent significant flood in 2007. The resulting solution represents flood characteristics such as inundation area, inundation depth and flow velocity. Model verification was performed by confrontation of the results with survey data. The model solution was overlaid with a street map of Jakarta. Finally, alternatives for flood mitigation measures are discussed.

  13. FLOODS CHARACTERISTIC TO THE PRUT RIVER (ROMANIA (I

    Directory of Open Access Journals (Sweden)

    G. ROMANESCU

    2015-03-01

    Full Text Available Foods characteristic to the Prut river (Romania. The Prut River springs from Ukraine and discharges into the Danube. It covers 952.9 km. It represents the State border between Ukraine, Romania, and the Republic of Moldova. The catchment basin is part of the temperate continental climate of transition, where rains are heavy. The flood waves of the upper sector are caused by the rains fallen in the Forested Carpathians. Because of slopes and high velocities, flood peaks are sharp, levels are very high and they unfold within a very short time frame. Flood waves (Rădăuți Prut upstream from the Stânca-Costești reservoir and within the lower sector (Prisăcani, Drănceni, Fălciu, Oancea present natural forms, with steep peaks and slopes. Flood waves downstream from the Stânca-Costești reservoir (Stânca Downstream, Ungheni are artificial, controlled by the dam. The flood wave of 2008 – the highest in the history of Prut River, with a maximum discharge of 4240 m3/s (initial calculated discharge 7146 m3/s – featured the most interesting characteristics: upstream from the dam, it was sharp, with extremely abrupt slopes; downstream from the dam, the flattened top maintained – with few alterations – as far as the gauging station of Oancea. At the Oancea station, it ended one month after the one corresponding to the Rădăuți Prut station. This study aims at demonstrating the influence of Stânca-Costești reservoir on the manifestation of flood waves within the upper and the lower sector.

  14. Missouri River Flood 2011 Vulnerabilities Assessment Report. Volume 2 - Technical Report

    Science.gov (United States)

    2012-10-01

    losses from disasters, such as floods. Section 2: Background 7 Figure 3. Potential Flood Area WYOMING Missouri River Pot.,m.l Rood ...erosion control demonstration program aimed at promoting lower cost erosion control techniques . From 1978 through 1982 the Omaha District constructed 29...projects were demonstrations of bio-stabilization techniques in McCone County, Montana and the other involved erosion control and river training

  15. Assessing Flood Risk Using Reservoir Flood Control Rules

    Institute of Scientific and Technical Information of China (English)

    Xiang Fu; Yadong Mei; Zhihuai Xiao

    2016-01-01

    The application of conventional flood operation regulation is restricted due to insufficient description of flood control rules for the Pubugou Reservoir in southern China. Based on the require-ments of different flood control objects, this paper proposes to optimize flood control rules with punish-ment mechanism by defining different parameters of flood control rules in response to flood inflow fore-cast and reservoir water level. A genetic algorithm is adopted for solving parameter optimization problem. The failure risk and overflow volume of the downstream insufficient flood control capacity are assessed through the reservoir operation policies. The results show that an optimised regulation can provide better performance than the current flood control rules.

  16. Operational river ice forecasting on the Peace River : managing flood risk and hydropower production

    Energy Technology Data Exchange (ETDEWEB)

    Jasek, M. [BC Hydro, Burnaby, BC (Canada); Friensenhan, E. [Alberta Environment, Edmonton, AB (Canada); Granson, W. [Alberta Environment, Peace River, AB (Canada)

    2007-07-01

    This paper described the procedures used jointly by Alberta Environment and BC Hydro to manage the water flows on the Peace River. The Alberta-British Columbia Joint Task Force on Peace River Ice (JTF) was concerned with the coordination of break-up ice observations along the river as well as ice jam flooding at the Town of Peace River (TPR), resulting from an induced dynamic break-up on the Smoky River, a main tributary of the Peace River. The TPR is the largest community that can be most affected by ice jams on river. As such, river ice processes on the river are monitored and subject to operational procedures of the JTF. These operating procedures are organized into 3 separate sequential phases, notably freeze-up procedures, mid-winter procedures, and break-up procedures. In April 2007, the ice break-up season on the Peace River and Smoky River, was particularly challenging as record high snow cover led to a dynamic break-up of these two streams. Costs due to reduced hydropower production were documented. This paper highlighted the main decision points for mitigation and presented the recommendations that improve mitigation efforts with benefits to both the flood prone community and the power utility. This paper revealed that forecasting the start of control flow by predicting the arrival of the ice front using the Comprehensive River Ice Simulation System Project (CRISSP) model was largely successful. Further work is underway to define the accuracy of forecasting the start of control flow using CRISSP, as accuracy of temperature forecasts appears to be the major uncertainty. The JTF was able to make successful recommendations for flow reductions. However, the need for an accurate hydrologic model for the Smoky River as well as other inflows between Peace Canyon and the TPR was emphasized. 4 refs., 31 figs.

  17. What are the hydro-meteorological controls on flood characteristics?

    Science.gov (United States)

    Nied, Manuela; Schröter, Kai; Lüdtke, Stefan; Nguyen, Viet Dung; Merz, Bruno

    2017-02-01

    Flood events can be expressed by a variety of characteristics such as flood magnitude and extent, event duration or incurred loss. Flood estimation and management may benefit from understanding how the different flood characteristics relate to the hydrological catchment conditions preceding the event and to the meteorological conditions throughout the event. In this study, we therefore propose a methodology to investigate the hydro-meteorological controls on different flood characteristics, based on the simulation of the complete flood risk chain from the flood triggering precipitation event, through runoff generation in the catchment, flood routing and possible inundation in the river system and floodplains to flood loss. Conditional cumulative distribution functions and regression tree analysis delineate the seasonal varying flood processes and indicate that the effect of the hydrological pre-conditions, i.e. soil moisture patterns, and of the meteorological conditions, i.e. weather patterns, depends on the considered flood characteristic. The methodology is exemplified for the Elbe catchment. In this catchment, the length of the build-up period, the event duration and the number of gauges undergoing at least a 10-year flood are governed by weather patterns. The affected length and the number of gauges undergoing at least a 2-year flood are however governed by soil moisture patterns. In case of flood severity and loss, the controlling factor is less pronounced. Severity is slightly governed by soil moisture patterns whereas loss is slightly governed by weather patterns. The study highlights that flood magnitude and extent arise from different flood generation processes and concludes that soil moisture patterns as well as weather patterns are not only beneficial to inform on possible flood occurrence but also on the involved flood processes and resulting flood characteristics.

  18. Flood Map for the Winooski River in Waterbury, Vermont, 2014

    Science.gov (United States)

    Olson, Scott A.

    2015-01-01

    From August 28 to 29, 2011, Tropical Storm Irene delivered rainfall ranging from approximately 4 to more than 7 inches in the Winooski River Basin in Vermont. The rainfall resulted in severe flooding throughout the basin and significant damage along the Winooski River. In response to the flooding, the U.S. Geological Survey (USGS), in cooperation with the Federal Emergency Management Agency, conducted a new flood study to aid in flood recovery and restoration and to assist in flood forecasting. The study resulted in two sets of flood maps that depict the flooding for an 8.3-mile reach of the Winooski River from about 1,000 feet downstream of the Waterbury-Bolton, Vermont, town line upstream to about 2,000 feet upstream of the Waterbury-Middlesex, Vt., town line.

  19. 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.

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

    Directory of Open Access Journals (Sweden)

    Mitková Veronika Bačová

    2016-12-01

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

  1. Artificial neural networks applied to flow prediction scenarios in Tomebamba River - Paute watershed, for flood and water quality control and management at City of Cuenca Ecuador

    Science.gov (United States)

    Cisneros, Felipe; Veintimilla, Jaime

    2013-04-01

    The main aim of this research is to create a model of Artificial Neural Networks (ANN) that allows predicting the flow in Tomebamba River both, at real time and in a certain day of year. As inputs we are using information of rainfall and flow of the stations along of the river. This information is organized in scenarios and each scenario is prepared to a specific area. The information is acquired from the hydrological stations placed in the watershed using an electronic system developed at real time and it supports any kind or brands of this type of sensors. The prediction works very good three days in advance This research includes two ANN models: Back propagation and a hybrid model between back propagation and OWO-HWO. These last two models have been tested in a preliminary research. To validate the results we are using some error indicators such as: MSE, RMSE, EF, CD and BIAS. The results of this research reached high levels of reliability and the level of error are minimal. These predictions are useful for flood and water quality control and management at City of Cuenca Ecuador

  2. Analysis on the Flood Rainstorm in the Lijiang River of Guilin

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    [Objective] The research aimed to study the flood rainstorm in the Lijiang River of Guilin. [Method] By using the observation data of flood rainstorm and water level in the Lijiang River, the flood rainstorm standard in the Lijiang River was delimited. Via the analysis on the spatial and temporal distribution, weather situation of flood rainstorm in South China, the flood rainstorm in the Lijiang River was systematically studied. [Result] The flood in the Lijiang River closely related to the duration and in...

  3. A proposal for mitigation of floods in main colombian rivers

    Science.gov (United States)

    Donado, L. D.; Bravo, E.; Ortiz, R. O.

    2012-04-01

    Floods are naturally produced by rainfall and are a worldwide threat, which cannot be controlled. The effects of the floods are not proportional to the magnitude of the events in different parts of the world. It is due to the local risk management and the reduction of the vulnerability. This research looks for the reduction of the effects of the heavy rainfall in the Magdalena River. Two main effects are detected: intensity of the rainfall and residence time of the flow in the river. Several factors were detected to increase the vulnerability of the Magdalena Valley. Those are the increase of sediment load caused by deforestation, mining and the lack of sustainable urban drainage systems. Unfortunately, the majority of the Colombian actions have been aimed to the construction of public works for "controlling" the effects of the floods and reducing the territory vulnerability without any technical reason but private interests. All the investments are done with no planning or management. In a continue review of all the dikes and walls to avoid river floods, we appreciate that the failure of this elements increased the territory vulnerability, generating false expectation of security. We propose some non-structural solutions in combination of structural ones for reducing costs of investments and emergency attention. The main conclusion of this work is based on the fact that natural hazards are unavoidable but they can be mitigated reducing the residence time of the water on the channels with the reactivation of old natural channels and constructing cutoff channels in the meandering valley.

  4. Lithologic and hydrologic controls of mixed alluvial-bedrock channels in flood-prone fluvial systems: bankfull and macrochannels in the Llano River watershed, central Texas, USA

    Science.gov (United States)

    Heitmuller, Frank T.; Hudson, Paul F.; Asquith, William H.

    2015-01-01

    The rural and unregulated Llano River watershed located in central Texas, USA, has a highly variable flow regime and a wide range of instantaneous peak flows. Abrupt transitions in surface lithology exist along the main-stem channel course. Both of these characteristics afford an opportunity to examine hydrologic, lithologic, and sedimentary controls on downstream changes in channel morphology. Field surveys of channel topography and boundary composition are coupled with sediment analyses, hydraulic computations, flood-frequency analyses, and geographic information system mapping to discern controls on channel geometry (profile, pattern, and shape) and dimensions along the mixed alluvial-bedrock Llano River and key tributaries. Four categories of channel classification in a downstream direction include: (i) uppermost ephemeral reaches, (ii) straight or sinuous gravel-bed channels in Cretaceous carbonate sedimentary zones, (iii) straight or sinuous gravel-bed or bedrock channels in Paleozoic sedimentary zones, and (iv) straight, braided, or multithread mixed alluvial–bedrock channels with sandy beds in Precambrian igneous and metamorphic zones. Principal findings include: (i) a nearly linear channel profile attributed to resistant bedrock incision checkpoints; (ii) statistically significant correlations of both alluvial sinuosity and valley confinement to relatively high f (mean depth) hydraulic geometry values; (iii) relatively high b (width) hydraulic geometry values in partly confined settings with sinuous channels upstream from a prominent incision checkpoint; (iv) different functional flow categories including frequently occurring events (values (most ≤ 0.45) that develop at sites with unit stream power values in excess of 200 watts per square meter (W/m2); and (vi) downstream convergence of hydraulic geometry exponents for bankfull and macrochannels, explained by co-increases of flood magnitude and noncohesive sandy sediments that collectively minimize

  5. Quality control of the RMS US flood model

    Science.gov (United States)

    Jankowfsky, Sonja; Hilberts, Arno; Mortgat, Chris; Li, Shuangcai; Rafique, Farhat; Rajesh, Edida; Xu, Na; Mei, Yi; Tillmanns, Stephan; Yang, Yang; Tian, Ye; Mathur, Prince; Kulkarni, Anand; Kumaresh, Bharadwaj Anna; Chaudhuri, Chiranjib; Saini, Vishal

    2016-04-01

    The RMS US flood model predicts the flood risk in the US with a 30 m resolution for different return periods. The model is designed for the insurance industry to estimate the cost of flood risk for a given location. Different statistical, hydrological and hydraulic models are combined to develop the flood maps for different return periods. A rainfall-runoff and routing model, calibrated with observed discharge data, is run with 10 000 years of stochastic simulated precipitation to create time series of discharge and surface runoff. The 100, 250 and 500 year events are extracted from these time series as forcing for a two-dimensional pluvial and fluvial inundation model. The coupling of all the different models which are run on the large area of the US implies a certain amount of uncertainty. Therefore, special attention is paid to the final quality control of the flood maps. First of all, a thorough quality analysis of the Digital Terrain model and the river network was done, as the final quality of the flood maps depends heavily on the DTM quality. Secondly, the simulated 100 year discharge in the major river network (600 000 km) is compared to the 100 year discharge derived using extreme value distribution of all USGS gauges with more than 20 years of peak values (around 11 000 gauges). Thirdly, for each gauge the modelled flood depth is compared to the depth derived from the USGS rating curves. Fourthly, the modelled flood depth is compared to the base flood elevation given in the FEMA flood maps. Fifthly, the flood extent is compared to the FEMA flood extent. Then, for historic events we compare flood extents and flood depths at given locations. Finally, all the data and spatial layers are uploaded on geoserver to facilitate the manual investigation of outliers. The feedback from the quality control is used to improve the model and estimate its uncertainty.

  6. 78 FR 77397 - Flood Control Regulations, Marshall Ford Dam (Mansfield Dam and Lake Travis), Colorado River, Texas

    Science.gov (United States)

    2013-12-23

    ..., school district, or special district with a population of less than 50,000; or (3) a small organization...--city of Hannibal; LCRA--Lower Colorado River Authority; M&T Irr--Modesto & Turlock Irr; Mrcd Irr...

  7. General Reevaluation and Environmental Impact Statement for Flood Control and Related Purposes, Sheyenne River, North Dakota. Volume 2. Technical Appendixes.

    Science.gov (United States)

    1984-01-01

    California studies indi- cate that more kinds of birds breed in riverine forests than in any other habitat type (Brumley, 1976; Gaines, 1977). Many...storage. Even with relatively short durations of flooding, the entire forest herbaceous layer, consisting of wildflowers and other herbs and grasses...Johnson. and McCormick, 1978, Pp. 184-189. Brumlev, T.D.1976. Upper Butte Basin Study. Admin. Rep. 76-1, California Departuent of Fish and Came, 30

  8. 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.

  9. Thinking on Flood Control Problems of Communism Channel Hehe River to Liuzhuang Gate Section%共产主义渠合河至刘庄闸段防洪问题的思考

    Institute of Scientific and Technical Information of China (English)

    申继先

    2014-01-01

    共产主义渠属海河流域漳卫河水系,卫河支流,是流域防洪体系的重要组成部分。共产主义渠防汛工作事关新乡市、卫辉市等城市和沿河村镇人民生命财产安全及京广铁路、石武高铁、京珠高速等重要设施的安全。本文对共产主义渠合河-刘庄闸段防洪工程的现状和存在问题展开分析,对做好该段河道防洪保安提出对策和建议。%Communism-Channel-belongs-to-Zhangwei-River-Water-System-in-Haihe-River-Basin-,-which-is-a-branch-of-Weihe-River-and-important-part-of-river-basin-flood-control-system-.Communism-Channel-flood-control-work-is-related-to-life-and-property-safety-of-people-in-Xinxiang-,-Weihui-and-other-cities-as-well-as-villages-and-towns-along-the-river-.It-also-relates-to-safety-of-Beijing-Guangzhou-Railway-,-Shijiazhuang-Wuhan-High-speed-Railway-,-Beijing-Zhuhai-Expressway-and-other-important-facilities-.In-the-paper-,-current-situation-and-problems-in-Communism-Channel-Hehe-River-to-Liuzhuang-Gate-Section-are-analyzed-,-countermeasures-and-suggestions-are-proposed-aiming-at-flood-control-and-guard-in-the-river-section-.

  10. THE LOWER EOCENE RODA SANDSTONE (SOUTH-CENTRAL PYRENEES:AN EXAMPLE OF A FLOOD-DOMINATED RIVER-DELTA SYSTEMIN A TECTONICALLY CONTROLLED BASIN

    Directory of Open Access Journals (Sweden)

    ROBERTO TINTERRI

    2007-07-01

    Full Text Available The lower Eocene Roda Sandstone (Figols Group, south-central Pyrenees mainly consists of mouth bars and delta-front sandstone lobes deposited in a flood-dominated river-delta system. The deposition of these bodies was strongly controlled by an interaction between flood-dominated gravity flows entering seawater, topographic confinement and tidal currents. The Roda Sandstone is made up of six depositional sequences of different hierarchical order each of which is characterized by a basal deltaic sandstone wedge (R1 to R6 that passes upward into a siltstone and mudstone interval. Each basal deltaic sandstone wedge is composed of three types of facies association and respective facies tract (sensu Mutti 1992 that, from proximal to distal zones, are indicated as T1, T2 and T3. These three facies tracts are created by the downcurrent evolution of different types of sediment-laden stream flows entering seawater and related hyperpycnal flows. Their deposits are constituted by three different types of coarse-grained mouth bars and corresponding fine-grained delta-front sandstone lobes. The tidal influence is present in facies tract T3 in the R5 and R6 sandstone units, where the passage between flood-dominated mouth bars and the delta-front sandstone lobes occurs through intermediate facies characterized by different types of sigmoidal-cross stratification whose meaning will be discussed. The basal deltaic sandstone wedges of Roda sandstone are characterized by a progressive forestepping culminating in the R6 unit that erodes the underlying R5 unit and by an overlying backstepping unit indicated as R7. The erosive surface at the base of R6 unit is interpreted as a sequence boundary that divides the Roda Sandstone into two parts: 1 an underlying highstand system tract (HST and falling stage system tract (FSST (units R1 to R5 and 2 an overlying low-stand delta (the R6 unit that passes upward into highstand mudstone through a transgressive system tract

  11. An Archaeological Survey: Shoreline of Lake Darling and Proposed Burlington Dam. Flood Control Project Area, Upper Souris River, North Dakota

    Science.gov (United States)

    1978-01-01

    Burlington (1948), Carpio, N.E. (1949), Grano (1949), Grano , S.W. (1949), Greene (1949), Tolley (1948), Mouse River Park (1949), Mouse River ParkN.E. (1949...miles southeast of Grano , OZ North Dakota. The site is adjacent to Lake Darling’s east bank and also near the eastern boundary of the Upper Souris...miles south of Grano , North .7. 6 i 4 76 .9 . . -a s . 9 , . . aG =. . _ . ,, . . . ., . . 9. 9 . , , , " Dakota. The site lies on a flat 800 meters

  12. Hydrologic sensitivity of flood runoff and inundation: 2011 Thailand floods in the Chao Phraya River basin

    Science.gov (United States)

    Sayama, T.; Tatebe, Y.; Iwami, Y.; Tanaka, S.

    2015-07-01

    The Thailand floods in 2011 caused unprecedented economic damage in the Chao Phraya River basin. To diagnose the flood hazard characteristics, this study analyses the hydrologic sensitivity of flood runoff and inundation to rainfall. The motivation is to address why the seemingly insignificant monsoon rainfall, or 1.2 times more rainfall than for past large floods, including the ones in 1995 and 2006, resulted in such devastating flooding. To quantify the hydrologic sensitivity, this study simulated long-term rainfall-runoff and inundation for the entire river basin (160 000 km2). The simulation suggested that the flood inundation volume was 1.6 times more in 2011 than for the past flood events. Furthermore, the elasticity index suggested that a 1 % increase in rainfall causes a 2.3 % increase in runoff and a 4.2 % increase in flood inundation. This study highlights the importance of sensitivity quantification for a better understanding of flood hazard characteristics; the presented basin-wide rainfall-runoff-inundation simulation was an effective approach to analyse the sensitivity of flood runoff and inundation at the river basin scale.

  13. 2003 Pearl River County, Mississippi Lidar: Flood Plain Management Project

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This lidar data was collected primarily for flood plain mapping within Pearl River County, MS. The data were processed into separate Bare Earth and First Surface...

  14. Safety in the Chemical Laboratory: Flood Control.

    Science.gov (United States)

    Pollard, Bruce D.

    1983-01-01

    Describes events leading to a flood in the Wehr Chemistry Laboratory at Marquette University, discussing steps taken to minimize damage upon discovery. Analyzes the problem of flooding in the chemical laboratory and outlines seven steps of flood control: prevention; minimization; early detection; stopping the flood; evaluation; clean-up; and…

  15. Facts and perceptions on the flood-risk evolution along the Po River

    Science.gov (United States)

    Domeneghetti, Alessio; Carisi, Francesca; Castellarin, Attilio

    2014-05-01

    Has the flood risk increased in the Po river basin during the last half century? The increasing frequency with which floods damages are recorded, or reported by media, strengthen the common perception that the flood risk is dramatically increasing in Europe and other areas of the world, due to a combination of different causes, among which climate change is often described as the major factor. However, there is a growing awareness of how anthropogenic pressures, such as uncontrolled urban and industrial expansion on flood-prone areas, may strongly impact the evolution of flood-risk in a given area, increasing potential flood damages and losses. Starting from these considerations, our study aims at shedding some light on the impact and relative importance of different factors controlling the flood risk. Focusing in particular on the middle-lower portion of the River Po, we analyse the evolution of flood hazard in the last half century referring to long streamflow series for different gauging stations located along the study reach (~450 km), while the modification of anthropogenic pressure is evaluated by referring to land-use and demographic dynamics observed from 1950s. Our study proposes simplified flood-vulnerability indices to be used for large scale flood-risk assessments and, on the basis of these indices, (1) we assess the importance of the different elements contributing to the definition of flood risk and (2) represent the evolution of flood risk in time along the middle and lower portion of the River Po. The results of the study represent an important piece of information that can be particularly useful to decision-makers in the definition of large scale flood-risk mitigation strategies and development plans for the study area.

  16. Dynamic ANN Modeling for Flood Forecasting in a River Network

    Science.gov (United States)

    Roy, Parthajit; Choudhury, P. S.; Saharia, Manabendra

    2010-10-01

    An experiment on predicting flood flows at each of the upstream and a down stream section of a river network is presented using focused Time Lagged Recurrent Neural Network with three different memories like TDNN memory, Gamma memory and Laguarre memory. This paper focuses on application of memory to the input layer of a TLRN in developing flood forecasting models for multiple sections in a river system. The study shows the Gamma memory has better applicability followed by TDNN and Laguarre memory.

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

    OpenAIRE

    Zhuowen Wang; Jun Liu; Cheng Gao

    2013-01-01

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

  18. Flood management on the lower Yellow River: hydrological and geomorphological perspectives

    Science.gov (United States)

    Shu, Li; Finlayson, Brian

    1993-05-01

    The Yellow River, known also as "China's Sorrow", has a long history of channel changes and disastrous floods in its lower reaches. Past channel positions can be identified from historical documentary records and geomorphological and sedimentological evidence. Since 1947, government policy has been aimed at containing the floods within artificial levees and preventing the river from changing its course. Flood control is based on flood-retarding dams and off-stream retention basins as well as artificial levees lining the channel. The design flood for the system has a recurrence interval of only around 60 years and floods of this and larger magnitudes can be generated downstream of the main flood control dams at Sanmenxia and Xiaolangdi. Rapid sedimentation along the river causes problems for storage and has raised the bed of the river some 10 m above the surrounding floodplain. The present management strategy is probably not viable in the long term and to avoid a major disaster a new management approach is required. The most viable option would appear to be to breach the levees at predetermined points coupled with advanced warning and evacuation of the population thus put at risk.

  19. Environmental Impact Statement. Flood Control, Burlington Dam, Souris River, North Dakota. Biological Assessment and Section 404(b) Evaluation.

    Science.gov (United States)

    1979-12-01

    Grano Crossing, and Renville County Road 9 to a level 5 feet above pre-project grades. The Soo Line Railroad crossing would be raised to 6 feet above...yards. Road raises of State Highway 28, Grano Crossing (FAS 3828), and Renville County Road 9 (FAS 3809) have been grouped together for discussion...north-south roads that cross the Souris River Valley 3 miles north of State Highway 5 and 1 mile north of the Soo Line crossing, respectively. Grano

  20. Review Report for Flood Control and Recreational Development, Little Colorado River at Holbrook, Arizona. Volume 2. Technical Appendix.

    Science.gov (United States)

    1980-09-01

    aquifer.. 12. The tributaries and msin stqin of the Little Colorad , River w largely unregulated. Although about 26 dam,’ with an stimated aggregate store...riparian, shadscale scrub, short grass , and Great Basin desert scrub. Except for large trees and shrubs associated with the riparian comunity, grasses and...olive, rabbitbrush, black bush, and snakemeed. Such grasses as blue and black gama, galleta, Indian ricegrass, saltgrcsa, and alkali sacaton are comon

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

    Science.gov (United States)

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

    2009-04-01

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

  2. Streamflow characterization and summary of water-quality data collection during the Mississippi River flood, April through July 2011

    Science.gov (United States)

    Welch, Heather L.; Barnes, Kimberlee K.

    2013-01-01

    From April through July 2011, the U.S. Geological Survey collected surface-water samples from 69 water-quality stations and 3 flood-control structures in 4 major subbasins of the Mississippi River Basin to characterize the water quality during the 2011 Mississippi River flood. Most stations were sampled at least monthly for field parameters suspended sediment, nutrients, and selected pesticides. Samples were collected at daily to biweekly frequencies at selected sites in the case of suspended sediment. Hydro-carbon analysis was performed on samples collected at two sites in the Atchafalaya River Basin to assess the water-quality implications of opening the Morganza Floodway. Water-quality samples obtained during the flood period were collected at flows well above normal streamflow conditions at the majority of the stations throughout the Mississippi River Basin and its subbasins. Heavy rainfall and snowmelt resulted in high streamflow in the Mississippi River Basin from April through July 2011. The Ohio River Subbasin contributed to most of the flow in the lower Mississippi-Atchafalaya River Subbasin during the months of April and May because of widespread rainfall, whereas snowmelt and precipitation from the Missouri River Subbasin and the upper Mississippi River Subbasin contributed to most of the flow in the lower Mississippi-Atchafalaya River Subbasin during June and July. Peak streamflows from the 2011 flood were higher than peak streamflow during previous historic floods at most the selected streamgages in the Mississippi River Basin. In the Missouri River Subbasin, the volume of water moved during the 1952 flood was greater than the amount move during the 2011 flood. Median concentrations of suspended sediment and total phosphorus were higher in the Missouri River Subbasin during the flood when compared to the other three subbasins. Surface water in the upper Mississippi River Subbasin contained higher median concentrations of total nitrogen, nitrate

  3. Floods of April 1952 in the Missouri River basin

    Science.gov (United States)

    Wells, J.V.B.

    1955-01-01

    The floods of April 1952 in the Milk River basin, along the Missouri River from the mouth of the Little Missouri River to the mouth of the Kansas River, and for scattered tributaries of the Missouri River in North and South Dakota were the greatest ever observed. The damage amounted to an estimated $179 million. The outstanding featur6 of the floods was the extraordinary peak discharge generated in the Missouri River at and downstream from Bismarck, N. Dak., on April 6 when a large ice jam upstream from the city was suddenly released. Inflow from flooding tributaries maintained the peak discharge at approximately the same magnitude in the transit of the flood across South Dakota; downstream from Yankton, S. Dak., attenuation of the peak discharge was continuous because of natural storage in the wide flood plains. The outstanding characteristic of floods in the Milk River basin was their duration--the flood crested at Havre, Mont., on April 3 and at Nashua, Mont.. on April 18. The floods were caused by an abnormally heavy accumulation of snow that was converted into runoff in a few days of very warm weather at the end of March. The heaviest water content of the snow pack at breakup was in a narrow arc extending through Aberdeen, S. Dak., Pierre, S. Dak.. and northwestward toward the southwest corner of North Dakota. The water content in part of this concentrated cover exceeded 6 inches. The winter of 1951-52, which followed a wet cold fall that made the ground impervious, was one of the most severe ever experienced in South Dakota and northern Montana. Depths of snow and low temperatures combined to produce, at the end of March, one of the heaviest snow covers in the history of the Great Plains. The Missouri River ice was intact upstream from Chamberlain, S. Dak., at the end of March, and the breakup of the ice with inflow of local runoff was one of the spectacular features of the flood. Runoff from the Yellowstone River combining with the flood pouring from the

  4. Flood-inundation maps for White River at Petersburg, Indiana

    Science.gov (United States)

    Fowler, Kathleen K.

    2015-08-20

    Digital flood-inundation maps for a 7.7-mile reach of the White River at Petersburg, Indiana, were created by the U.S. Geological Survey (USGS), in cooperation with the Indiana Office of Community and Rural Affairs. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage at White River at Petersburg, Ind. (03374000). Near-real-time stages at this streamgage may be obtained from the USGS National Water Information System at http://waterdata.usgs.gov/ or the National Weather Service (NWS) Advanced Hydrologic Prediction Service at http:/water.weather.gov/ahps/, which also forecasts flood hydrographs at this site (PTRI3).

  5. Discharges of past flood events based on historical river profiles

    Directory of Open Access Journals (Sweden)

    D. Sudhaus

    2008-10-01

    Full Text Available This paper presents a case study on the estimation of peak discharges of extreme flood events during the 19th century of the Neckar River located in south-western Germany. It was carried out as part of the BMBF (German Federal Ministry of Education and Research research project RIMAX (Risk Management of Extreme Flood Events. The discharge estimations were made for the 1824 and 1882 flood events, and are based on historical cross profiles. The 1-D model Hydrologic Engineering Centers River Analysis System (HEC-RAS was applied with different roughness coefficients to determine these estimations. The results are compared (i with contemporary historical calculations for the 1824 and 1882 flood events and (ii in the case of the flood event in 1824, with the discharge simulation by the water balance model LARSIM (Large Area Runoff Simulation Model. These calculations are matched by the HEC-RAS simulation based on the standard roughness coefficients.

  6. 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.

  7. Flood frequency analysis of Ganga river at Haridwar and Garhmukteshwar

    Science.gov (United States)

    Kamal, Vikas; Mukherjee, Saumitra; Singh, P.; Sen, R.; Vishwakarma, C. A.; Sajadi, P.; Asthana, H.; Rena, V.

    2016-02-01

    The Ganga River is a major river of North India and is known for its fertile alluvium deposits formed due to floods throughout the Indo-Gangetic plains. Flood frequency analysis has been carried out through various approaches for the Ganga River by many scientists. With changes in river bed brought out by anthropogenic changes the intensity of flood has also changed in the last decade, which calls for further study. The present study is in a part of the Upper Indo-Ganga plains subzone 1(e). Statistical distributions applied on the discharge data at two stations found that for Haridwar lognormal and for Garhmukteshwar Gumbel EV1 is applicable. The importance of this study lies in its ability to predict the discharge for a return period after a suitable distribution is found for an area.

  8. Flood frequency analysis of Ganga river at Haridwar and Garhmukteshwar

    Science.gov (United States)

    Kamal, Vikas; Mukherjee, Saumitra; Singh, P.; Sen, R.; Vishwakarma, C. A.; Sajadi, P.; Asthana, H.; Rena, V.

    2017-07-01

    The Ganga River is a major river of North India and is known for its fertile alluvium deposits formed due to floods throughout the Indo-Gangetic plains. Flood frequency analysis has been carried out through various approaches for the Ganga River by many scientists. With changes in river bed brought out by anthropogenic changes the intensity of flood has also changed in the last decade, which calls for further study. The present study is in a part of the Upper Indo-Ganga plains subzone 1(e). Statistical distributions applied on the discharge data at two stations found that for Haridwar lognormal and for Garhmukteshwar Gumbel EV1 is applicable. The importance of this study lies in its ability to predict the discharge for a return period after a suitable distribution is found for an area.

  9. Real-time flood forecasting of Huai River with flood diversion and retarding areas

    Institute of Scientific and Technical Information of China (English)

    Li Zhijia; Bao Hongjun; Xue Cangsheng; Hu Yuzhong; Fang Hong

    2008-01-01

    A combination of the rainfall-runoff module of the Xin'anjiang model, the Muskingum routing method, the water stage simulating hydrologic method, the diffusion wave nonlinear water stage method, and the real-time error correction method is applied to the real-time flood forecasting and regulation of the Huai River with flood diversion and retarding areas. The Xin'anjiang model is used to forecast the flood discharge hydrograph of the upstream and tributary. The flood routing of the main channel and flood diversion areas is based on the Muskingum method. The water stage of the downstream boundary condition is calculated with the water stage simulating hydrologic method and the water stages of each cross section are calculated from downstream to upstream with the diffusion wave nonlinear water stage method. The input flood discharge hydrograph from the main channel to the flood diversion area is estimated with the fixed split ratio of the main channel discharge. The flood flow inside the flood retarding area is calculated as a reservoir with the water balance method. The faded-memory forgetting factor least square of error series is used as the real-time error correction method for forecasting discharge and water stage. As an example, the combined models were applied to flood forecasting and regulation of the upper reaches of the Huai River above Lutaizi during the 2007 flood season. The forecast achieves a high accuracy and the results show that the combined models provide a scientific way of flood forecasting and regulation for a complex watershed with flood diversion and retarding areas.

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

    Science.gov (United States)

    McIntosh, J.; Lander, K.

    2016-12-01

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

  11. 基于SWMM的滨海城市河道防洪能力核算方法%SWMM-based Calculation Method for River Flood-control Capacity in Seashore City

    Institute of Scientific and Technical Information of China (English)

    刘兴坡

    2012-01-01

    针对当前滨海城市整治河道防洪能力核算过程中存在的河道断面形状不规则、需要考虑潮水顶托影响以及河道糙率难以准确选取等问题,在SWMM软件的基础上,结合灵敏度分析等相关方法,实现了河道防洪能力的科学核算.研究表明,该方法不仅是可行的,而且对提高城市河道整治的优化水平具有明显作用.%The current calculation of river flood-control capacity in seashore city is facing many problems, such as irregular river cross-section, backwater tide, inaccurate roughness coefficient and so on. In order to solve the above problems, SWMM software, incorporating parameter sensitivity analysis, was used for scientific calculation of river flood-control capacity. This approach is feasible and also helpful to enhance the optimal level of urban river renovation.

  12. Flood tracking chart for the Illinois River basin

    Science.gov (United States)

    Avery, Charles F.; Holmes, Jr., Robert R.; Sharpe, Jennifer B.

    1998-01-01

    This Flood Tracking Chart for the Illinois River Basin in Illinois can be used to record and compare the predicted or current flood-crest stage to past flood-crest information. This information can then be used by residents and emergency-response personnel to make informed decisions concerning the threat of flooding to life and property. The chart shows a map of the Illinois River Basin (see below), the location of real-time streamflow-gaging stations in the basin, graphs of selected historical recorded flood-crest stages at each of the stations, and sea-level conversion (SLC) factors that allow conversion of the current or predicted flood-crest stage to elevation above sea level. Each graph represents a streamflow-gaging station and has a space to record the most current river stage reported for that station by the U.S. Geological Survey (USGS). The National Weather Service (NWS) predicts flood crests for many of the stations shown on this chart.

  13. Geomorphological Impacts of an extreme Flood in Karoon River, Iran

    Science.gov (United States)

    Yousefi, Saleh; Mirzaee, Somaya; Keesstra, Saskia; Piegay, Herve; Pourghasemi, Hamid Reza

    2017-04-01

    An extreme flood occurred on 14.04.2016 in Kroon River. Using the OLI Landsat images on 08.04.2016 (before flood) and 24.04.2016 (after flood) the morphological evolution in different land cover types by this flood event were detected. The results show that the event significantly affected the channel width. The main effect was the high mobilization of channel sediments and severe bank erosion in the studied meandering reach. According to field surveys, the flood occupied the whole channel corridor and even some of the flood plain parts, but the channel pattern was not markedly changed. Results show the average of active channel width increased from 192 m to 256 m respectively for before and after flood. Statistical results indicate a significant change for active channel width and sinuosity index at 99% confidence level for both indexes. Findings show that the channel morphological changes (channel widening) varied significantly in different land cover types along the Karoon River banks. Specifically, the channel has widened less in the residential areas than the other land cover types, which is the result of bank protection activities. Keywords: Remote sensing, fluvial geomorphology, floodplain management, river evolution.

  14. Quantifying flooding regime in floodplain forests to guide river restoration

    Directory of Open Access Journals (Sweden)

    Christian O. Marks

    2014-09-01

    Full Text Available Abstract Determining the flooding regime needed to support distinctive floodplain forests is essential for effective river conservation under the ubiquitous human alteration of river flows characteristic of the Anthropocene Era. At over 100 sites throughout the Connecticut River basin, the largest river system in New England, we characterized species composition, valley and channel morphology, and hydrologic regime to define conditions promoting distinct floodplain forest assemblages. Species assemblages were dominated by floodplain-associated trees on surfaces experiencing flood durations between 4.5 and 91 days/year, which were generally well below the stage of the two-year recurrence interval flood, a widely-used benchmark for floodplain restoration. These tree species rarely occurred on surfaces that flooded less than 1 day/year. By contrast abundance of most woody invasive species decreased with flooding. Such flood-prone surfaces were jointly determined by characteristics of the hydrograph (high discharges of long duration and topography (low gradient and reduced valley constraint, resulting in increased availability of floodplain habitat with increasing watershed area and/or decreasing stream gradient. Downstream mainstem reaches provided the most floodplain habitat, largely associated with low-energy features such as back swamps and point bars, and were dominated by silver maple (Acer saccharinum. However, we were able to identify a number of suitable sites in the upper part of the basin and in large tributaries, often associated with in-channel islands and bars and frequently dominated by sycamore (Platanus occidentalis and flood disturbance-dependent species. Our results imply that restoring flows by modifying dam operations to benefit floodplain forests on existing surfaces need not conflict with flood protection in some regional settings. These results underscore the need to understand how flow, geomorphology, and species traits

  15. Interactions between the flooding regime and floodplain grasslands in the Tana River Delta, in Kenya

    Science.gov (United States)

    Leauthaud, Crystele; Musila, Winfred; Duvail, Stéphanie; Kergoat, Laurent; Hiernaux, Pierre; Grippa, Manuela; Albergel, Jean

    2017-04-01

    The floodplain grasslands of the Tana River Delta, located on the East African coast in Kenya, form part of an intertwined socio-ecological deltaic system of high biodiversity value that delivers numerous goods and services. Mainly composed of Echinochloa stagnina (Retz) P. Beauv., a high-value forage species, this ecosystem is the major dry-season grazing grounds of the local pastoralist communities. The construction of hydroelectric infrastructure has led to a modification of the flooding regime. The impacts of the resulting reduction of floods in the deltaic zone on ecosystem properties and services still need to be assessed. In such a perspective, this study characterizes the link between the flooding regime of the Tana River and the growth pattern of its floodplain grassland. Aboveground dry phytomass was sampled for 15 months under a wide variety of naturally flooded and non-flooded conditions and controlled irrigation and cutting frequency treatments. Annual aboveground dry phytomass attained high values between 11 T.ha-1 and 32 T.ha-1 and annual net primary production of the grasslands reached 35 T.ha-1.year-1. Growth rates clearly depended on the flooding regime, management and climate conditions and were on average more than twice as fast during, and 50% faster after the floods, relative to pre-flood conditions. A plant growth model allowed testing the effect of different flooding regimes on plant productivity, confirming very low productivity in the absence of floods. These results suggest that rangeland and water management for the Tana River deltaic wetlands are tightly linked. The projected construction of another dam could lead to a reduction of flood extent and period and a decrease of grassland productivity and growth duration. Mitigation of this type of negative impacts, which will have direct and adverse consequences for the pastoralist communities as well as on the delivery of other goods and services, needs to be undertaken.

  16. Flood forecasting and alert system for Arda River basin

    Science.gov (United States)

    Artinyan, Eram; Vincendon, Beatrice; Kroumova, Kamelia; Nedkov, Nikolai; Tsarev, Petko; Balabanova, Snezhanka; Koshinchanov, Georgy

    2016-10-01

    The paper presents the set-up and functioning of a flood alert system based on SURFEX-TOPODYN platform for the cross-border Arda River basin. The system was built within a Bulgarian-Greek project funded by the European Territorial Cooperation (ETC) Programme and is in operational use since April 2014. The basin is strongly influenced by Mediterranean cyclones during the autumn-winter period and experiences dangerous rapid floods, mainly after intensive rain, often combined with snow melt events. The steep mountainous terrain leads to floods with short concentration time and high river speed causing damage to settlements and infrastructure. The main challenge was to correctly simulate the riverflow in near-real time and to timely forecast peak floods for small drainage basins below 100 km2 but also for larger ones of about 1900 km2 using the same technology. To better account for that variability, a modification of the original hydrological model parameterisation is proposed. Here we present the first results of a new model variant which uses dynamically adjusted TOPODYN river velocity as function of the computed partial streamflow discharge. Based on historical flooding data, river sections along endangered settlements were included in the river flow forecasting. A continuous hydrological forecast for 5 days ahead was developed for 18 settlements in Bulgaria and for the border with Greece, thus giving enough reaction time in case of high floods. The paper discusses the practical implementation of models for the Arda basin, the method used to calibrate the models' parameters, the results of the calibration-validation procedure and the way the information system is organised. A real case of forecasted rapid floods that occurred after the system's finalisation is analysed. One of the important achievements of the project is the on-line presentation of the forecasts that takes into account their temporal variability and uncertainty. The web presentation includes a

  17. Concentrations and transport of suspended sediment, nutrients, and pesticides in the lower Mississippi-Atchafalaya River subbasin during the 2011 Mississippi River flood, April through July

    Science.gov (United States)

    Welch, Heather L.; Coupe, Richard H.; Aulenbach, Brent T.

    2014-01-01

    High streamflow associated with the April–July 2011 Mississippi River flood forced the simultaneous opening of the three major flood-control structures in the lower Mississippi-Atchafalaya River subbasin for the first time in history in order to manage the amount of water moving through the system. The U.S. Geological Survey (USGS) collected samples for analysis of field properties, suspended-sediment concentration, particle-size, total nitrogen, nitrate plus nitrite, total phosphorus, orthophosphate, and up to 136 pesticides at 11 water-quality stations and 2 flood-control structures in the lower Mississippi-Atchafalaya River subbasin from just above the confluence of the upper Mississippi and Ohio Rivers downstream from April through July 2011. Monthly fluxes of suspended sediment, suspended sand, total nitrogen, nitrate plus nitrite, total phosphorus, orthophosphate, atrazine, simazine, metolachlor, and acetochlor were estimated at 9 stations and 2 flood-control structures during the flood period. Although concentrations during the 2011 flood were within the range of what has been observed historically, concentrations decreased during peak streamflow on the lower Mississippi River. Prior to the 2011 flood, high concentrations of suspended sediment and nitrate were observed in March 2011 at stations downstream of the confluence of the upper Mississippi and Ohio Rivers, which probably resulted in a loss of available material for movement during the flood. In addition, the major contributor of streamflow to the lower Mississippi-Atchafalaya River subbasin during April and May was the Ohio River, whose water contained lower concentrations of suspended sediment, pesticides, and nutrients than water from the upper Mississippi River. Estimated fluxes for the 4-month flood period were still quite high and contributed approximately 50 percent of the estimated annual suspended sediment, nitrate, and total phosphorus fluxes in 2011; the largest fluxes were estimated at

  18. Application Study of Empirical Model and Xiaohuajian Flood Forecasting Model in the Middle Yellow River

    Science.gov (United States)

    Hu, Caihong

    2013-04-01

    Xiaolandi-Huayuankou region is an important rainstorm centre in the middle Yellow river, which drainage area of 35883km2. A set of forecasting methods applied in this region was formed throughout years of practice. The Xiaohuajian flood forecasting model and empirical model were introduced in this paper. The simulated processes of the Xiaohuajian flood forecasting model include evapotranspiration, infiltration, runoff, river flow. Infiltration and surface runoff are calculated utilizing the Horton model for infiltration into multilayered soil profiles. Overland flow is routed by Nash instantaneous unit hydrograph and Section Muskingum method. The empirical model are simulated using P~Pa~R and empirical relation approach for runoff generation and concentration. The structures of these two models were analyzed and compared in detail. Yihe river basin located in Xiaolandi-Huayuankou region was selected for the purpose of the study. The results show that the accuracy of the two methods are similar, however, the accuracy of Xiaohuajian flood forecasting model for flood forecasting is relatively higher, especially the process of the flood; the accuracy of the empirical methods is much worse, but it can also be accept. The two models are both practicable, so the two models can be combined to apply. The result of the Xiaohuajian flood forecasting model can be used to guide the reservoir for flood control, and the result of empirical methods can be as a reference.

  19. Flood hydrology and methylmercury availability in coastal plain rivers.

    Science.gov (United States)

    Bradley, Paul M; Journey, Celeste A; Chapelle, Francis H; Lowery, Mark A; Conrads, Paul A

    2010-12-15

    Mercury (Hg) burdens in top-predator fish differ substantially between adjacent South Carolina Coastal Plain river basins with similar wetlands coverage. In the Congaree River, floodwaters frequently originate in the Blue Ridge and Piedmont regions, where wetlands coverage and surface water dissolved methylmercury (MeHg) concentrations are low. Piedmont-driven flood events can lead to downward hydraulic gradients in the Coastal Plain riparian wetland margins, inhibiting MeHg transport from wetland sediments, and decreasing MeHg availability in the Congaree River habitat. In the adjacent Edisto River basin, floodwaters originate only within Coastal Plain sediments, maintaining upward hydraulic gradients even during flood events, promoting MeHg transport to the water column, and enhancing MeHg availability in the Edisto River habitat. These results indicate that flood hydrodynamics contribute to the variability in Hg vulnerability between Coastal Plain rivers and that comprehensive regional assessment of the relationship between flood hydrodynamics and Hg risk in Coastal Plain streams is warranted.

  20. Flood hydrology and methylmercury availability in Coastal Plain rivers

    Science.gov (United States)

    Bradley, Paul M.; Journey, Celeste A.; Chapelle, Francis H.; Lowery, Mark A.; Conrads, Paul A.

    2010-01-01

    Mercury (Hg) burdens in top-predator fish differ substantially between adjacent South Carolina Coastal Plain river basins with similar wetlands coverage. In the Congaree River, floodwaters frequently originate in the Blue Ridge and Piedmont regions, where wetlands coverage and surface water dissolved methylmercury (MeHg) concentrations are low. Piedmont-driven flood events can lead to downward hydraulic gradients in the Coastal Plain riparian wetland margins, inhibiting MeHg transport from wetland sediments, and decreasing MeHg availability in the Congaree River habitat. In the adjacent Edisto River basin, floodwaters originate only within Coastal Plain sediments, maintaining upward hydraulic gradients even during flood events, promoting MeHg transport to the water column, and enhancing MeHg availability in the Edisto River habitat. These results indicate that flood hydrodynamics contribute to the variability in Hg vulnerability between Coastal Plain rivers and that comprehensive regional assessment of the relationship between flood hydrodynamics and Hg risk in Coastal Plain streams is warranted.

  1. Quantification of increased flood risk due to global climate change for urban river management planning.

    Science.gov (United States)

    Morita, M

    2011-01-01

    Global climate change is expected to affect future rainfall patterns. These changes should be taken into account when assessing future flooding risks. This study presents a method for quantifying the increase in flood risk caused by global climate change for use in urban flood risk management. Flood risk in this context is defined as the product of flood damage potential and the probability of its occurrence. The study uses a geographic information system-based flood damage prediction model to calculate the flood damage caused by design storms with different return periods. Estimation of the monetary damages these storms produce and their return periods are precursors to flood risk calculations. The design storms are developed from modified intensity-duration-frequency relationships generated by simulations of global climate change scenarios (e.g. CGCM2A2). The risk assessment method is applied to the Kanda River basin in Tokyo, Japan. The assessment provides insights not only into the flood risk cost increase due to global warming, and the impact that increase may have on flood control infrastructure planning.

  2. WATERSHED RUNOFFAND RIVER FLOOD MODELING IN LAND USE PLANNING

    Directory of Open Access Journals (Sweden)

    Marcello Niedda

    2010-06-01

    Full Text Available In land use planning along river paths it may be useful to consider the statistics of the flooding process of the river. The set of rules regulating land use planning in Italy results in the return period required being very long and, as a result, there are very high river discharge peaks which are taken into consideration and not much possibility of making experimental observations. Correct planning of land use should include some description of river flooding in these critical conditions. To do this a basin scale hydrological model and a robust numerical scheme of the 2D complete SWE have to be integrated. Knowing that experimental validation is very difficult we showed the reliability of the numerical schemes used to get consistent solutions. A watershed runoff forecast model was used to obtain the river hydrograph to apply as a boundary condition in the study of river flood inundation on the flat plain near the Olbia airport (Sardinia, Italy. A threshold of 1 cm was used as a condition to consider whether or not to include the cell in the computational field in the description of the wetting-drying process. And this seems to fit well in the model. The numerical model is conservative, ensuring preservation of water volumes with a precision of 10-4. The great surface water gradient in some sections is evident proof of the importance of the SWE inertial terms in wave front propagation. The flow peak loss during the alluvial plane flooding resulted in a reduction of about 10% of the discharge peak at the river mouth. This numerical method, which has been validated in previous similar applications, describes sufficiently well flooding in a complex area with river morphology limited by airport and road infrastructures.

  3. Cultural Resource Inventory of Lands in and Adjacent to the City of Rochester, Minnesota Flood Control Project on the South Fork Zumbro River,

    Science.gov (United States)

    1981-09-14

    Control Structure in Blakesley Slough Waterfowl Production Area on the Ponune de Terre River, Grant County, Minnesota; Archae- - ological Field...of the Proposed U.S. Fish and Wildlife Service Earthen Dike and Water Control Structure in Blakesley Slough Waterfowl Production Area on the Pomme de... Terre River, Grant County, Minnesota; Archae- ological Field Services, Inc.; Principal Investigator. 1978 Records Search of the Proposed Trunk Highways

  4. 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.

  5. Creating Flood Inundation Maps For Lower Sakarya River

    Directory of Open Access Journals (Sweden)

    Osman Sönmez

    2013-06-01

    Full Text Available The Sakarya River Basin in Turkey frequently floods. The allure of riverside settlement and of nutrient-rich riverbank soil has led to extensive residential and agricultural development in flood plains. In this study, the 100 years return period possible flood carrying capacites of last 113 km of the Lower Sakarya Riverbed were investigated, also dam break and risk analyses were performed by applying different scenarios for the floods likely to occur. Flooding scenarios and water depth within the floodplain during these scenarios were calculated with the HEC-RAS software program and results were converted into a map in HEC-GeoRAS,ArcGIS 9x and ArcView 3.2 programs. As a result, it was observed that the Lower Sakarya River is susceptible to flooding. Recent observations of the study area confirm the study findings. This study tries to underscore the importance of taking into account the different scenarios regarding flood prevention and reduction studies.

  6. THE FLOOD RISK IN THE LOWER GIANH RIVER: MODELLING AND FIELD VERIFICATION

    Directory of Open Access Journals (Sweden)

    NGUYEN H. D.

    2016-03-01

    Full Text Available Problems associated with flood risk definitely represent a highly topical issue in Vietnam. The case of the lower Gianh River in the central area of Vietnam, with a watershed area of 353 km2, is particularly interesting. In this area, periodically subject to flood risk, the scientific question is strongly linked to risk management. In addition, flood risk is the consequence of the hydrological hazard of an event and the damages related to this event. For this reason, our approach is based on hydrodynamic modelling using Mike Flood to simulate the runoff during a flood event. Unfortunately the data in the studied area are quite limited. Our computation of the flood risk is based on a three-step modelling process, using rainfall data coming from 8 stations, cross sections, the topographic map and the land-use map. The first step consists of creating a 1-D model using Mike 11, in order to simulate the runoff in the minor river bed. In the second step, we use Mike 21 to create a 2-D model to simulate the runoff in the flood plain. The last step allows us to couple the two models in order to precisely describe the variables for the hazard analysis in the flood plain (the water level, the speed, the extent of the flooding. Moreover the model is calibrated and verified using observational data of the water level at hydrologic stations and field control data (on the one hand flood height measurements, on the other hand interviews with the community and with the local councillors. We then generate GIS maps in order to improve flood hazard management, which allows us to create flood hazard maps by coupling the flood plain map and the runoff speed map. Our results show that: the flood peak, caused by typhoon Nari, reached more than 6 m on October 16th 2013 at 4 p.m. (its area was extended by 149 km². End that the typhoon constitutes an extreme flood hazard for 11.39%, very high for 10.60%, high for 30.79%, medium for 31.91% and a light flood hazard for 15

  7. 2 Dimensional Hydrodynamic Flood Routing Analysis on Flood Forecasting Modelling for Kelantan River Basin

    Directory of Open Access Journals (Sweden)

    Azad Wan Hazdy

    2017-01-01

    Full Text Available Flood disaster occurs quite frequently in Malaysia and has been categorized as the most threatening natural disaster compared to landslides, hurricanes, tsunami, haze and others. A study by Department of Irrigation and Drainage (DID show that 9% of land areas in Malaysia are prone to flood which may affect approximately 4.9 million of the population. 2 Dimensional floods routing modelling demonstrate is turning out to be broadly utilized for flood plain display and is an extremely viable device for evaluating flood. Flood propagations can be better understood by simulating the flow and water level by using hydrodynamic modelling. The hydrodynamic flood routing can be recognized by the spatial complexity of the schematization such as 1D model and 2D model. It was found that most of available hydrological models for flood forecasting are more focus on short duration as compared to long duration hydrological model using the Probabilistic Distribution Moisture Model (PDM. The aim of this paper is to discuss preliminary findings on development of flood forecasting model using Probabilistic Distribution Moisture Model (PDM for Kelantan river basin. Among the findings discuss in this paper includes preliminary calibrated PDM model, which performed reasonably for the Dec 2014, but underestimated the peak flows. Apart from that, this paper also discusses findings on Soil Moisture Deficit (SMD and flood plain analysis. Flood forecasting is the complex process that begins with an understanding of the geographical makeup of the catchment and knowledge of the preferential regions of heavy rainfall and flood behaviour for the area of responsibility. Therefore, to decreases the uncertainty in the model output, so it is important to increase the complexity of the model.

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

    Directory of Open Access Journals (Sweden)

    Zhuowen Wang

    2013-09-01

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

  9. 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...

  10. Automatic control of pollutant on a shallow river using surface water systems: application to the Ebro River.

    Science.gov (United States)

    Puig, V; Romera, J; Quevedo, J; Sarrate, R; Morales-Hernandez, M; Gonzalez-Sanchis, M; Garcia-Navarro, P

    2014-01-01

    In this paper, the problem of automatic control of pollutant on a shallow river using surface water systems is addressed using a benchmark test case based in the Ebro River. The Ebro River presents flooding episodes in the city of Zaragoza in Spring when snow melts in the Pyrenees. To avoid flooding and high pollutant levels in living areas, some lands outside the city are prepared to be flooded. Going one step further, this paper is focused on the pollutant level control at a certain point downstream of the river under flooding episodes, and several control strategies for that purpose are presented and tested.

  11. 1999年长江洪水及几点认识%The 1999 Flood on Changjiang River and Some Thoug hts on It

    Institute of Scientific and Technical Information of China (English)

    WANG; Sheng-fu

    2001-01-01

    Following the basin wide heavy flood on Changjiang River in 1998, a si gnificant flood occurred in 1999. Comparative analysis of both floods in terms of flows and flooding situations shows that both floods had one common feature, that is, the flood stages were fairly high. But they differed greatly at the sa me time, that is, the 1998 flood was a basin wide heavy one while the 1999 flood was a significant local one. At Yichang station there occurred eight flood pea ks in 1998, while in 1999 only three peaks took place. The maximum peak dischar ge at this station in 1999 was 57 600 cubic meters per second, which was smaller than that in 1998. The maximum flood-volume in 30 d of the 1998 flood at this s t ation equaled that in 1954, when an extraordinary heavy flood happened on the River, while the maximum flood-volume in 30 d in 1999 was 25.8 billion cubic me t ers per second smaller than the 1998 one. It is seen that inflow floods from th e upstream Changjiang River (above Yichang) in 1999 were not so big. Comparison of flood volumes in longer period shows that the 1999 flood was relatively conc entrated while the 1998 one had lasted longer duration. Analysis shows that flo oding situations in both years differed significantly in terms of the flood volu mes diverted from river channels due to dyke breaches and collapses, the cases o f polder embankment collapses, the areas of inundated cultivated land and the nu mbers of dangerous events for hydraulic structures. These differences had been resulted from the different properties of both floods and the dyke strengthening efforts made after the 1998 flood. It is seen that flood control engineering c onstructions initiated in the days following the 1998 flood have played an impor tant role in fighting the 1999 flood.

  12. Hydroclimatological Aspects of the Extreme 2011 Assiniboine River Basin Flood

    Science.gov (United States)

    Brimelow, J.; Szeto, K.; Bonsal, B. R.; Hanesiak, J.; Kochtubajda, B.; Stewart, R. E.

    2014-12-01

    In the spring and early summer of 2011, the Assiniboine River Basin in Canada experienced an extreme flood that was unprecedented in terms of duration and volume of water. The flood had significant socioeconomic impacts and caused over one billion dollars in damage. Contrary to what one might expect for such an extreme flood, individual precipitation events before and during the 2011 flood were not extreme; instead, it was the cumulative impact and timing of precipitation events going back to the summer of 2010 that played a key role in the 2011 flood. The summer and fall of 2010 were exceptionally wet, resulting in soil moisture levels being much above normal at the time of freeze up. This was followed by above-average precipitation during the winter of 2010-2011, and record-breaking basin-averaged snow-water equivalent values in March and April 2011. Abnormally cold temperatures in March delayed the spring melt by about two weeks, with the result that the above-average seasonal melt freshet occurred close to the onset of abnormally heavy rains in May and June. The large-scale atmospheric flow during May and June 2011 favoured increased cyclone activity over the central and northern U.S., which produced an anomalously large number of heavy rainfall events over the basin. All of these factors combined to generate extreme surface runoff and flooding. We used JRA-55 reanalysis data to quantify the relative importance of snowmelt, soil moisture and spring precipitation in contributing to the unprecedented flood and to demonstrate how the 2011 flood was unique compared to previous floods in the basin. Data and research from this study can be used to validate and improve flood forecasting techniques over this important basin; our findings also raise important questions regarding the impact of climate change on basins that experience pluvial and nival flooding.

  13. Climate Change Impacts on River Floods: Uncertainty and Adaptation

    NARCIS (Netherlands)

    Wang, L.

    2015-01-01

    The modelling frameworks, which include greenhouse gas emission scenarios, climate models, downscaling methods and hydrological models, are generally used to assess climate change impacts on river floods. In this research, the uncertainty associated with each component of the modelling framework is

  14. 75 FR 17393 - Intent To Prepare a Draft Environmental Impact Statement for the “Flood Control, Mississippi...

    Science.gov (United States)

    2010-04-06

    ... ``Flood Control, Mississippi River & Tributaries, St. Johns Bayou and New Madrid Floodway, Missouri, First... environmental, economic and social impacts of alternative plans to provide flood control and develop and discuss... of the 1928 Flood Control Act. A levee closure and outlet structure at New Madrid, Missouri...

  15. The tele-connections of long duration floods and their implications for dynamically updating the Flood Control Pool

    Science.gov (United States)

    Devineni, Naresh; Najibi, Nasser; Lall, Upmanu

    2016-04-01

    Traditional approaches to flood risk assessment are typically indexed to an instantaneous peak flow event at a specific recording gage on a river, and then extrapolated through hydraulic modeling of that peak flow to the potential area that is likely to be inundated. However, property losses tend to be determined as much by the duration and volume of flooding as by the depth and velocity of inundation. We argue that the existing notion of a flood risk assessment and consequent reservoir flood control operations needs to be revisited, especially for floods due to persistent rainfall (>30 day duration). Our interest lies in explicitly understanding the dependence of the likelihood or frequency and intensity of extreme regional floods on a causal chain of ocean-atmosphere processes whose slow variation and regime-like changes translate into significant and persistent changes in the probability of major floods in the large river basins. An understanding and mapping of these factors into a dynamic risk framework is important for establishing a process by which flood risk for large basins could be systematically updated reflecting changing climate conditions, whether due to human influence, or as part of the natural cycles of climate variation. In this study, we developed an inference system for climate informed flood risk assessment using an integrated statistical modeling approach. We first develop multivariate flood attributes and classify their characteristic spatial variability using the hierarchical clustering approach. Depending on the flood event type, different rainfall inducing mechanisms (e.g. tropical storm, local convection, frontal system, recurrent tropical waves) may be involved with characteristic spatial scales and statistical properties. Hence, we identify the antecedent rainfall conditions for the flood types and map their corresponding specific atmospheric circulation patterns using compositing of the NCEP/NCAR reanalysis data and the storm tracks

  16. Characterization of the regional variability of flood regimes within the Omo-Gibe River Basin, Ethiopia

    Science.gov (United States)

    Yared, Adanech; Demissie, Solomon S.; Sivapalan, Murugesu; Viglione, Alberto; MacAlister, Charlotte

    2014-05-01

    Hydrological variability and seasonality is one of the Ethiopia's primary water resource management challenges. Variability is most obviously manifest in endemic, devastating droughts and floods. While the level of flooding is quite often extremely high and destroys human beings and property, in many cases flooding is of vital importance because the community benefits from flood recession agriculture. This is the case of the lower Omo plain whose agriculture is based on the regularity of the inundations due to flooding of the Omo Gibe River. The big flood in 2006, which caused death for more than 300 people and 2000 cattle, poses a dilemma. Flooding must be controlled and regulated in a way that the damages are reduced as much as possible but the flooding-related benefits are not lost. To this aim, characterization and understanding of hydrological variability of the Omo Gibe River basin is fundamental. The goal of this work is to extract the maximal amount of information on the hydrological variability and specially on the flooding regime from the few data available in the region. Because most of the basin is ungauged, hydrological information is reconstructed using the data from 9 gauged catchments. A daily water balance model has been developed, calibrated and validated for 9 gauged catchments and, subsequently, the parameters have been correlated to catchment characteristics in order to establish a functional relationship that allows to apply the model to ungauged catchments. Daily streamflow has been predicted for 15 ungauged catchments, which are assumed to comprehensively represent the hydrological variability of the Omo-Gibe River Basin. Even though both northern and southern catchments are affected by a strong seasonality of precipitation, with most of the rain falling in less than 3 months, most of the northern catchments are humid, while in the southern part of the Omo-Gibe River basin, the catchments are either humid, dry sub humid, semiarid or arid. As

  17. Vulnerability of schools to floods in Nyando River catchment, Kenya.

    Science.gov (United States)

    Ochola, Samuel O; Eitel, Bernhard; Olago, Daniel O

    2010-07-01

    This paper assesses the vulnerability of schools to floods in the Nyando River catchment (3,600 km(2)) in western Kenya and identifies measures needed to reduce this vulnerability. It surveys 130 schools in the lower reaches, where flooding is a recurrent phenomenon. Of the primary schools assessed, 40% were vulnerable, 48% were marginally vulnerable and 12% were not vulnerable. Of the secondary schools, 8% were vulnerable, 73% were marginally vulnerable and 19% were not vulnerable. Vulnerability to floods is due to a lack of funds, poor building standards, local topography, soil types and inadequate drainage. The Constituencies Development Fund (CDF), established in 2003, provides financial support to cover school construction and reconstruction costs; CDF Committees are expected to adopt school building standards. In an effort to promote safe and resilient construction and retrofitting to withstand floods, this paper presents vulnerability reduction strategies and recommendations for incorporating minimum standards in the on-going Primary School Infrastructure Programme Design.

  18. Prevention from Dike Failure by Emergency Flood Control Measures

    Directory of Open Access Journals (Sweden)

    Koppe Baerbel

    2016-01-01

    Full Text Available The risk of failure of a flood protection system must always be taken into account. During flooding events, appropriate interim protection systems must be at hand and ready to be deployed to support weak and overloaded structures. Usually sandbags, eventually in combination with fascines and geotextiles, are in use to defend endangered dike stretches in case of emergency. Sandbags offer highly flexible employment, however the enormous personal, material and time consuming efforts required for installation and dismantling are problematic. Therefore, more effective constructions for emergency flood control are needed. Within the research projects HWS-Mobile, DeichSCHUTZ, and DeichKADE different constructions based on the use of flexible membranes have been developed or are in development to ensure easy and effective countermeasures to secure dike stretches, which are in risk of breakage. Successful applications of the developed systems have taken place during the catastrophic flood event at the river Elbe in Northern Germany in 2013.

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

    Science.gov (United States)

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

    2017-04-01

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

  20. On the value of satellite-based river discharge and river flood data

    Science.gov (United States)

    Kettner, A. J.; Brakenridge, R.; van Praag, E.; Borrero, S.; Slayback, D. A.; Young, C.; Cohen, S.; Prades, L.; de Groeve, T.

    2015-12-01

    Flooding is the most common natural hazard worldwide. According to the World Resources Institute, floods impact 21 million people every year and affect the global GDP by $96 billion. Providing accurate flood maps in near-real time (NRT) is critical to their utility to first responders. Also, in times of flooding, river gauging stations on location, if any, are of less use to monitor stage height as an approximation for water surface area, as often the stations themselves get washed out or peak water levels reach much beyond their design measuring capacity. In a joint effort with NASA Goddard Space Flight Center, the European Commission Joint Research Centre and the University of Alabama, the Dartmouth Flood Observatory (DFO) measures NRT: 1) river discharges, and 2) water inundation extents, both with a global coverage on a daily basis. Satellite-based passive microwave sensors and hydrological modeling are utilized to establish 'remote-sensing based discharge stations'. Once calibrated, daily discharge time series span from 1998 to the present. Also, the two MODIS instruments aboard the NASA Terra and Aqua satellites provide daily floodplain inundation extent with global coverage at a spatial resolution of 250m. DFO's mission is to provide easy access to NRT river and flood data products. Apart from the DFO web portal, several water extent products can be ingested by utilizing a Web Map Service (WMS), such as is established with for Latin America and the Caribbean (LAC) region through the GeoSUR program portal. This effort includes implementing over 100 satellite discharge stations showing in NRT if a river is flooding, normal, or in low flow. New collaborative efforts have resulted in flood hazard maps which display flood extent as well as exceedance probabilities. The record length of our sensors allows mapping the 1.5 year, 5 year and 25 year flood extent. These can provide key information to water management and disaster response entities.

  1. Monitoring the effects of floods on submerged macrophytes in a large river.

    Science.gov (United States)

    Ibáñez, Carles; Caiola, Nuno; Rovira, Albert; Real, Montserrat

    2012-12-01

    The lower Ebro River (Catalonia, Spain) has recently undergone a regime shift from a phytoplankton to a macrophyte-dominated system. Macrophytes started to spread at the end of the 1990s and since 2002 artificial floods (flushing flows) of short duration (1-2 days) are released from the Riba-roja dam once or twice a year in order to reduce macrophyte density. The aim of this study was to analyse the spatiotemporal trends of the submerged macrophytes in two stretches of the lower Ebro River using high-resolution hydroacoustic methods, in order to elucidate the effects of artificial floods and natural floods on its distribution and abundance. Results showed that the mean cover in the two studied stretches (Móra and Ginestar) was not reduced after a flushing flow (from 36.59% to 55.85% in Móra, and from 21.18% to 21.05% in Ginestar), but it was greatly reduced after the natural flood (down to 9.79% in Móra and 2.04% in Ginestar); surprisingly the cover increased in Móra after the artificial flood. In order to increase the efficiency of floods in controlling macrophyte spreading, the magnitude and frequency of them should largely increase, as well as the suspended sediment load, approaching as much as possible to the original flood pattern before dam construction. Hydroacoustic methods combined with geostatistics and interpolation in GIS can accurately monitor spatiotemporal trends of submerged macrophytes in large rivers. This is the first article to apply this monitoring system to submerged macrophytes in rivers. Copyright © 2012 Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

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

    2014-01-01

    Regional change in the variability and magnitude of flooding could be a major consequence of future global climate change. Extreme floods have the capacity to rapidly transform landscapes and expose landscape vulnerabilities through highly variable spatial patterns of inundation, erosion, and deposition. We use the historic activation of the Birds Point-New Madrid Floodway during the Mississippi and Ohio River Flooding of 2011 as a scientifically unique stress experiment to analyze indicators of floodplain vulnerability. We use pre- and postflood airborne Light Detection and Ranging data sets to locate erosional and depositional hotspots over the 540 km2 agricultural Floodway. While riparian vegetation between the river and the main levee breach likely prevented widespread deposition, localized scour and deposition occurred near the levee breaches. Eroded gullies nearly 1 km in length were observed at a low ridge of a relict meander scar of the Mississippi River. Our flow modeling and spatial mapping analysis attributes this vulnerability to a combination of erodible soils, flow acceleration associated with legacy fluvial landforms, and a lack of woody vegetation to anchor soil and enhance flow resistance. Results from this study could guide future mitigation and adaptation measures in cases of extreme flooding.

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

    Science.gov (United States)

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

    2014-01-01

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

  4. The combined impact on the flooding in Vietnam's Mekong River delta of local man-made structures, sea level rise, and dams upstream in the river catchment

    Science.gov (United States)

    Le, Thi Viet Hoa; Nguyen, Huu Nhan; Wolanski, Eric; Tran, Thanh Cong; Haruyama, Shigeko

    2007-01-01

    The Mekong River delta plays an important role in the Vietnamese economy and it has been severely impacted during this century by a series of unusually large floods. In the dry season the delta is also impacted by salinity intrusion and tides. These effects have caused severe human hardship. To mitigate these impacts, a large number of engineering structures, primarily dykes and weirs, have been built in the delta in recent years and are still being built, mainly to control floods and saltwater intrusion. These control measures are still being upgraded. A GIS-linked numerical model shows that the flood levels in the delta depend on the combined impacts of high river flows in the Mekong River, storm surges, sea level rise, and the likely, future siltation of the Mekong Estuary resulting from the construction of dams in China as well as many other dams proposed throughout the remaining river catchment. The model suggests that the engineering structures in the delta increase the flow velocities in the rivers and canals, increasing bank erosion, and cause the water to be deeper in the rivers and canals. This increases flooding in the non-protected areas of the delta and increases the risk of catastrophic failure of the dykes in the protected areas. The model also predicts that a sea level rise induced by global warming will enhance flooding in the Mekong River delta in Vietnam, and that flooding may worsen in the long term as a result of estuarine siltation resulting from the construction of dams. At the scale of the Mekong River basin, a multinational water resources management plan is needed that includes the hydrological needs of the delta. At the scale of the delta, a compromise is needed between allowing some flooding necessary for agriculture and preventing catastrophic flooding to alleviate human suffering.

  5. What drives flood trends along the Rhine River: climate or river training?

    Directory of Open Access Journals (Sweden)

    S. Vorogushyn

    2012-12-01

    Full Text Available The Rhine River catchment was heavily trained over the past decades and faced the construction of the Rhine weir cascade, flood protection dikes and detention basins. For the same time period, several studies detected positive trends in flood flows and faced the challenge of flood trend attribution, i.e. identifying the drivers of observed change. The presented study addresses the question about the responsible drivers for changes in annual maximum daily flows at Rhine gauges starting from Maxau down to Lobith. In particular, the role of river training measures including the Rhine weir cascade and a series of detention basins in enhancing Rhine floods was investigated. By applying homogenisation relationships to the original 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, the relative changes in the homogenised time series were found to be smaller up to about 20% points 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 was partly caused by the unfavourable superposition of the Rhine and Neckar flood waves. It resulted from the acceleration of the Rhine waves due to construction of the weir cascade. However, at the same time, the tributary flows across the entire Upper and Lower Rhine, which enhance annual Rhine peaks, showed very strong positive trends. This suggests the dominance of a large-scale driver such as climate variability/change which acted along with river training. In particular, the analysis suggests that the river training measures fell in a period with increasing flood trends driven by factors other than river training of the Rhine main channel.

  6. Flood inundation maps for the Wabash and Eel Rivers at Logansport, Indiana

    Science.gov (United States)

    Fowler, Kathleen K.

    2014-01-01

    Digital flood-inundation maps for an 8.3-mile reach of the Wabash River and a 7.6-mile reach of the Eel River at Logansport, Indiana (Ind.), were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at USGS streamgage Wabash River at Logansport, Ind. (sta. no. 03329000) and USGS streamgage Eel River near Logansport, Ind. (sta. no. 03328500). Current conditions for estimating near-real-time areas of inundation using USGS streamgage information may be obtained on the Internet at http://waterdata.usgs.gov/. In addition, information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system http:/water.weather.gov/ahps/). The NWS forecasts flood hydrographs at many places that are often colocated with USGS streamgages. NWS-forecasted peak-stage information may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. For this study, flood profiles were computed for the stream reaches by means of a one-dimensional step-backwater model developed by the U.S. Army Corps of Engineers. The hydraulic model was calibrated by using the most current stage-discharge relations at USGS streamgages 03329000, Wabash River at Logansport, Ind., and 03328500, Eel River near Logansport, Ind. The calibrated hydraulic model was then used to determine five water-surface profiles for flood stage at 1-foot intervals referenced to the Wabash River streamgage datum, and four water-surface profiles for flood stages at 1-foot intervals referenced to the Eel River streamgage datum. The stages range from bankfull to approximately the highest

  7. A Framework for Flood Risk Analysis and Benefit Assessment of Flood Control Measures in Urban Areas.

    Science.gov (United States)

    Li, Chaochao; Cheng, Xiaotao; Li, Na; Du, Xiaohe; Yu, Qian; Kan, Guangyuan

    2016-08-05

    Flood risk analysis is more complex in urban areas than that in rural areas because of their closely packed buildings, different kinds of land uses, and large number of flood control works and drainage systems. The purpose of this paper is to propose a practical framework for flood risk analysis and benefit assessment of flood control measures in urban areas. Based on the concept of disaster risk triangle (hazard, vulnerability and exposure), a comprehensive analysis method and a general procedure were proposed for urban flood risk analysis. Urban Flood Simulation Model (UFSM) and Urban Flood Damage Assessment Model (UFDAM) were integrated to estimate the flood risk in the Pudong flood protection area (Shanghai, China). S-shaped functions were adopted to represent flood return period and damage (R-D) curves. The study results show that flood control works could significantly reduce the flood risk within the 66-year flood return period and the flood risk was reduced by 15.59%. However, the flood risk was only reduced by 7.06% when the flood return period exceeded 66-years. Hence, it is difficult to meet the increasing demands for flood control solely relying on structural measures. The R-D function is suitable to describe the changes of flood control capacity. This frame work can assess the flood risk reduction due to flood control measures, and provide crucial information for strategy development and planning adaptation.

  8. The effects of Thailand's Great Flood of 2011 on river sediment discharge in the upper Chao Phraya River basin, Thailand

    Institute of Scientific and Technical Information of China (English)

    Butsawan Bidorn; Seree Chanyotha; Stephen A. Kish; Joseph F. Donoghue; Komkrit Bidorn; Ruetaitip Mama

    2015-01-01

    Severe flooding that occurred during the 2011 monsoon season in Thailand was the heaviest flooding in the past 50 yr. The rainfall over the northern part of Thailand, especially during July–August 2011, was 150% higher than average. During the flooding period, river flows of the four major Chao Phraya River tributaries (Ping, Wang, Yom, and Nan rivers) increased in the range of 1.4–5 times the average discharge. This study examined the river sediment discharge of the four major rivers in the upper Chao Phraya River basin in Thailand. The four rivers are considered the main sources of sediment supply to the Chao Phraya Estuary. River surveys of the Ping, Wang, Yom, and Nan rivers were carried out in October 2011 (during the Great Flood) and October 2012 (one year after the flood). Survey data included river cross sections, flow velocities, suspended sediment concentrations, and bed load transport in each river. Analyses of these data indicated that total sediment transport rates for the four main rivers during the flooding of 2011 were 2.3–5.6 times higher than the average sediment discharge over 60 yr. The flood of 2011 sig-nificantly affected the sediment characteristics including the proportions of suspended and bed sediment loads in each river though in different ways. The rates of sediment transport per unit discharge for the Ping and Wang rivers dramatically increased during the 2011 flood, but the flooding had minimal effects on the sediment characteristics in the Yom and Nan rivers. The amount of total sediment discharge in each river caused by the 2011 flooding varied between 0.3 and 1.6 Mt. Additionally, the bed load transport in these rivers varied between ? 0%and 26%of the suspended sediment discharge.

  9. Channel morphology and its impact on flood passage, the Tianjiazhen reach of the middle Yangtze River

    Science.gov (United States)

    Shi, Yafeng; Zhang, Qiang; Chen, Zhongyuan; Jiang, Tong; Wu, Jinglu

    2007-03-01

    The Tianjiazhen reach of the middle Yangtze is about 8 km long, and characterized by a narrow river width of 650 m and local water depth of > 90 m in deep inner troughs, of which about 60 m is below the mean sea level. The troughs in the channel of such a large river are associated with regional tectonics and local lithology. The channel configuration plays a critical role in modifying the height and duration of river floods and erosion of the riverbed. The formation of the troughs in the bed of the Yangtze is considered to be controlled by sets of NW-SE-oriented neotectonic fault zones, in which some segments consist of highly folded thick Triassic limestone crossed by the Yangtze River. Several limestone hills, currently located next to the river channel, serve as nodes that create large vortices in the river, thereby accelerating downcutting on the riverbed composed of limestone highly susceptible to physical corrosion and chemical dissolution. Hydrological records indicate that the nodal hills and channel configuration at Tianjiazhen do not impact on normal flow discharges but discharges > 50,000 m 3s - 1 are slowed down for 2-3 days. Catastrophic floods are held up for even longer periods. These inevitably result in elevated flood stages upstream of prolonged duration, affecting large cities such as Wuhan and a very large number of people.

  10. Influences on flood frequency distributions in Irish river catchments

    Directory of Open Access Journals (Sweden)

    S. Ahilan

    2011-04-01

    Full Text Available This study explores influences which result in shifts of flood frequency distributions in Irish rivers. Generalised Extreme Value (GEV type I distributions are recommended in Ireland for estimating flood quantiles. 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. Of these 126 rivers, 25 have multiple gauging stations. Analysis of this data was undertaken to explore hydraulic and hydro-geological factors that influence flood frequency distributions and whether shifts in distributions occur in the down-river direction. The methodology involved determining the shape parameter of GEV distributions that were fitted to AM data at each site and to statistically test this shape parameter to determine whether a type I, type II or type III distribution was valid. The classification of these distributions was further supported by moment and L-moment diagrams and probability plots. Results indicated that of the 143 stations with flow records exceeding 25 yr, data for 92 was best represented by GEV type I distributions and that for another 12 and 39 stations followed type II and type III distributions respectively. The spatial, hydraulic and hydro-geological influences on flood frequency distributions were assessed by incorporating results on an Arc-GIS platform with individual layers showing karst features, flood attenuation polygons and lakes. This data reveals that type I distributions are spatially well represented throughout the country. The majority of type III distributions appear in four distinct clusters in well defined geographical areas where attenuation influences from floodplains and lakes appear to be influential. The majority of type II distributions appear to be in a single cluster in a region in the west of the country that is characterised by a karst landscape. The

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

    Science.gov (United States)

    Zhang, Xiaolei; Song, Yuqin

    2014-11-01

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

  12. Detection of Flood Inundation Information of the Kinu River Flooding in 2015 by Social Media

    Science.gov (United States)

    Shi, Y.; Sayama, T.; Takara, K. T.

    2016-12-01

    On September 10th, 2015, due to Kanto Tohoku heavy rainfall in Japan, an overtopping occurred from the Kinu River around 6:00. At the same day, levee breach occurred at the downstream area near Joso city in Ibaraki Prefecture, Japan. This flood disaster caused two people dead, several people injured, and enormous damages on houses and infrastructures in the city. In order to mitigate such flood disasters with large inundations, it is important to identify flood-affected areas on real-time basis. The real-time flood hazard map, which is our ultimate goal of the study, provides information on location of inundated areas during a flood. However, the technology has not been achieved yet mainly due to the difficulty in identifying the flood extent on real time. With the advantage of efficiency and wide coverage, social media, such as Twitter, appears as a good data source for collecting real-time flood information. However, there are some concerns on social media information, including the trustworthiness, and the amount of useful information in the case tweets from flood affected areas. This study collected tweet regarding the Kinu River flooding and investigated how many people in affected area posted tweets on the flooding and how the detected information is useful for the eventual goal on the real-time flood hazard mapping. The tweets were collected by three ways: advanced search on twitter web page; DISAster-information ANAlyzer system; and Twitter Application Programming Interfaces. As a result, 109 disaster relevant tweets were collected. Out of the 109 tweets, 32% of the total tweets are posted at real-time, 43% of total tweets are posted with photos and 46 tweets are related to the inundation information. 46% of the inundation related tweets were able to identify locations. In order to investigate the reliability of tweet post, the location identified tweets were marked on map to compare with the real inundation extent that measured by the Geospatial

  13. The effects of flooding on dioxin and PCB levels in food produced on industrial river catchments.

    Science.gov (United States)

    Lake, Iain R; Foxall, Christopher D; Fernandes, Alwyn; Lewis, Mervyn; Rose, Martin; White, Oliver; Lovett, Andrew A; White, Shaun; Dowding, Alan; Mortimer, David

    2015-04-01

    This research examined the effect of regular flooding upon PCDD/F and PCB levels in milk, beef and lamb, produced on the floodplains of industrial river catchments. Our unique dataset included more than 200 samples analysed for PCDD/Fs and PCBs over two data collection phases (1998-1999 & 2008-2010) from working farms. A robust paired study design was adopted with samples taken from flood-prone farms and nearby control farms not subject to flooding. On industrial river catchments regular flooding is associated with higher PCDD/F and PCB levels in soils and grass. This contamination may be transferred to food but the impact varied by food type. These contrasts may be due to physiological differences between animals, the ages at which they are sent to market and differences in animal husbandry. To minimise the risks of producing food on flood-prone land in industrial river catchments, as well as on any land with elevated PCDD/F and PCB levels, this research suggests a number of options. The choice of livestock may be important and as an example in our study beef cattle accumulated PCDD/Fs to a higher degree than sheep. Land management may also play a role and could include minimising the time that livestock spend on such land or feeding commercial feed, low in PCDD/Fs and PCBs, where appropriate.

  14. Deposition of radiocesium on the river flood plains around Fukushima.

    Science.gov (United States)

    Saegusa, Hiromitsu; Ohyama, Takuya; Iijima, Kazuki; Onoe, Hironori; Takeuchi, Ryuji; Hagiwara, Hiroki

    2016-11-01

    The environment in the area around Fukushima Daiichi Nuclear Power Plant has been contaminated by widely deposited significant amount of radioactive materials, which were released to the atmosphere caused by the Fukushima Daiichi Nuclear Power Plant accident due to the Great East Japan Earthquake, which occurred on March 11, 2011. The radiocesium released in the accident mainly affects radiation dose in the environment. Decontamination work in the contaminated area except a mountain forests has been conducted to decrease the radiation dose. However, there are concerns that the redistribution of this radiation due to water discharge will occur due to the resulting transport of radiocesium. In particular, the deposition of soil particles containing radiocesium on the flood plains in the downstream areas of Fukushima's rivers can potentially increase the local radiation dose. Therefore, it is important to understand the influence of the deposition behavior of radiocesium on the radiation dose. Investigations of rivers have been performed to enhance the understanding of the mechanisms by which radiocesium is deposited on these flood plains. It was found that the spatial distribution of the radiocesium concentration on the flood plain along the river is heterogeneous with a dependence on the depositional condition and that the number of points with high air dose rates is limited. In detail, the radiocesium concentration and air dose rates in flood channels are higher than those at the edges of the river channels. Based on these heterogeneity and hydrological events, the deposition and transport mechanisms of the radiocesium due to water discharge at rivers were also interpreted, and a conceptual model was constructed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Evidence of floods on the Potomac River from anatomical abnormalities in the wood of flood-plain trees

    Science.gov (United States)

    Yanosky, Thomas M.

    1983-01-01

    Ash trees along the Potomac River flood plain near Washington, D.C., were studied to determine changes in wood anatomy related to flood damage, and anomalous growth was compared to flood records for April 15 to August 31, 1930-79. Collectively, anatomical evidence was detected for 33 of the 34 growing-season floods during the study period. Evidence of 12 floods prior to 1930 was also noted, including catastrophic ones in 1889 and 1924. Trees damaged after the transition from earlywood to latewood growth typically formed ' flood rings ' of enlarged vessels within the latewood zone. Trees damaged near the beginning of the growth year developed flood rings within, or contiguous with, the earlywood. Both patterns are assumed to have developed when flood-damaged trees produced a second crop of leaves. Trees damaged by high-magnitude floods developed well formed flood rings along the entire height and around the entire circumference of the stem. Small floods were generally associated wtih diffuse or discontinuous anomalies restricted to stem apices. Frequency of flood rings was positively related to flood magnitude, and time of flood generation during the tree-growth season was estimated from the radial position of anomalous growth relative to annual ring width. Reconstructing tree heights in a year of flood-ring formation gives a minimum stage estimate along local stream reaches. Some trees provided evidence of numerous floods. Those with the greatest number of flood rings grew on frequently flooded surfaces subject to flood-flow velocities of at least 1 m/s, and more typically greater than 2 m/s. Tree size, more than age, was related to flood-ring formation. Trees kept small by frequent flood damage had more flood rings than taller trees of comparable age. (USGS)

  16. Flood-inundation maps for Grand River, Red Cedar River, and Sycamore Creek near Lansing, Michigan

    Science.gov (United States)

    Whitehead, Matthew; Ostheimer, Chad J.

    2015-08-26

    Digital flood-inundation maps for a total of 19.7 miles of the Grand River, the Red Cedar River, and Sycamore Creek were created by the U.S. Geological Survey (USGS) in cooperation with the City of Lansing, Michigan, and the U.S. Army Corps of Engineers. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, show estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at three USGS streamgages: Grand River at Lansing, MI (04113000), Red Cedar River at East Lansing, MI (04112500), and Sycamore Creek at Holt Road near Holt, MI (04112850). Near-real-time stages at these streamgages can 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 at http:/water.weather.gov/ahps/, which also forecasts flood hydrographs at all of these sites.

  17. Development of a flood-warning network and flood-inundation mapping for the Blanchard River in Ottawa, Ohio

    Science.gov (United States)

    Whitehead, Matthew T.

    2011-01-01

    Digital flood-inundation maps of the Blanchard River in Ottawa, Ohio, were created by the U.S. Geological Survey (USGS) in cooperation with the U.S. Department of Agriculture, Natural Resources Conservation Service and the Village of Ottawa, Ohio. The maps, which correspond to water levels (stages) at the USGS streamgage at Ottawa (USGS streamgage site number 04189260), were provided to the National Weather Service (NWS) for incorporation into a Web-based flood-warning Network that can be used in conjunction with NWS flood-forecast data to show areas of predicted flood inundation associated with forecasted flood-peak stages. Flood profiles were computed by means of a step-backwater model calibrated to recent field measurements of streamflow. The step-backwater model was then used to determine water-surface-elevation profiles for 12 flood stages with corresponding streamflows ranging from less than the 2-year and up to nearly the 500-year recurrence-interval flood. The computed flood profiles were used in combination with digital elevation data to delineate flood-inundation areas. Maps of the Village of Ottawa showing flood-inundation areas overlain on digital orthophotographs are presented for the selected floods. As part of this flood-warning network, the USGS upgraded one streamgage and added two new streamgages, one on the Blanchard River and one on Riley Creek, which is tributary to the Blanchard River. The streamgage sites were equipped with both satellite and telephone telemetry. The telephone telemetry provides dual functionality, allowing village officials and the public to monitor current stage conditions and enabling the streamgage to call village officials with automated warnings regarding flood stage and/or predetermined rates of stage increase. Data from the streamgages serve as a flood warning that emergency management personnel can use in conjunction with the flood-inundation maps by to determine a course of action when flooding is imminent.

  18. Restoring the Mississippi River Basin from the Catchment to the Coast Defines Science and Policy Issues of Ecosystem Services Associated with Alluvial and Coastal Deltaic Floodplains: Soil Conservation, Nutrient Reduction, Carbon Sequestration, and Flood Control

    Science.gov (United States)

    Twilley, R.

    2014-12-01

    through rethinking how we manage the Mississippi River not only to provide for navigation and flood control, but also as the critical source of sediments to stabilize degrading wetlands, will restoration be realized in a 100-year project cycle.

  19. FLOODS AND DROUGHT - HYDROCLIMATIC RISKS IN SUHA RIVER BASIN

    Directory of Open Access Journals (Sweden)

    TÎRNOVAN ALINA

    2014-03-01

    Full Text Available Suha is a right tributary of Moldova River, and presents a typical discharge for the geographical unit of Obcinele Bucovinei. Data used in the paper have been taken from Siret Basin Water Administration, Bacău, and represent a time sequence of 40 years. The most significant floods occurred in 1975, 1981, 1984, 1991, 2005, 2006, 2007 and 2008. The most obvious droughts occurred in 1969, 1974, 1978, 1983, 1987 and 2001. It was observed that the evolution of hydrological risk phenomena is closely linked to climatic changes. Increasing population and the need to extend the building design must take into account the extreme values of river flow over time, water resources also being important. Because extreme events occur more often, considering preventive plans against floods is needed. For this reason are analyzed the temperatures, rainfalls and discharge rates.

  20. Interactions between land use and flood management in the Chi River Basin

    NARCIS (Netherlands)

    Kuntiyawichai, K.

    2012-01-01

    The damages and hardships caused by floods and flooding remain an issue and are continuously increasing in the Chi River Basin, Thailand. It is difficult to make an accurate assessment of the costs and consequences associated with floods. However, flood hazards can also be seen as an opportunity, a

  1. 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

  2. Collaborative GIS for flood susceptibility mapping: An example from Mekong river basin of Viet Nam

    Science.gov (United States)

    Thanh, B.

    2016-12-01

    Flooding is one of the most dangerous natural disasters in Vietnam. Floods have caused serious damages to people and made adverse impact on social economic development across the country, especially in lower river basin where there is high risk of flooding as consequences of the climate change and social activities. This paper presents a collaborative platform of a combination of an interactive web-GIS framework and a multi-criteria evaluation (MCE) tool. MCE is carried out in server side through web interface, in which parameters used for evaluation are groups into three major categories, including (1) climatic factor: precipitation, typhoon frequency, temperature, humidity (2) physiographic data: DEM, topographic wetness index, NDVI, stream power index, soil texture, distance to river (3) social factor: NDBI, land use pattern. Web-based GIS is based on open-source technology that includes an information page, a page for MCE tool that users can interactively alter parameters in flood susceptible mapping, and a discussion page. The system is designed for local participation in prediction of the flood risk magnitude under impacts of natural processes and human intervention. The proposed flood susceptibility assessment prototype was implemented in the Mekong river basin, Viet Nam. Index images were calculated using Landsat data, and other were collected from authorized agencies. This study shows the potential to combine web-GIS and spatial analysis tool to flood hazard risk assessment. The combination can be a supportive solution that potentially assists the interaction between stakeholders in information exchange and in disaster management, thus provides for better analysis, control and decision-making.

  3. Linking the historic 2011 Mississippi River flood to coastal wetland sedimentation

    Science.gov (United States)

    Falcini, Federico; Khan, Nicole S.; Macelloni, Leonardo; Horton, Benjamin P.; Lutken, Carol B.; McKee, Karen L.; Santoleri, Rosalia; Colella, Simone; Li, Chunyan; Volpe, Gianluca; D’Emidio, Marco; Salusti, Alessandro; Jerolmack, Douglas J.

    2012-01-01

    Wetlands in the Mississippi River deltaic plain are deteriorating in part because levees and control structures starve them of sediment. In Spring of 2011 a record-breaking flood brought discharge on the lower Mississippi River to dangerous levels, forcing managers to divert up to 3500 m3/s-1 of water to the Atchafalaya River Basin. Here we quantify differences between the Mississippi and Atchafalaya River inundation and sediment-plume patterns using field-calibrated satellite data, and assess the impact these outflows had on wetland sedimentation. We characterize hydrodynamics and suspended sediment patterns of the Mississippi River plume using in-situ data collected during the historic flood. We show that the focused, high-momentum jet from the leveed Mississippi delivered sediment far offshore. In contrast, the plume from the Atchafalaya was more diffuse; diverted water inundated a large area; and sediment was trapped within the coastal current. Maximum sedimentation (up to several centimetres) occurred in the Atchafalaya Basin despite the larger sediment load carried by the Mississippi. Minimum accumulation occurred along the shoreline between these river sources. Our findings provide a mechanistic link between river-mouth dynamics and wetland sedimentation patterns that is relevant for plans to restore deltaic wetlands using artificial diversions.

  4. Relationship of Rainfall Distribution and Water Level on Major Flood 2014 in Pahang River Basin, Malaysia

    National Research Council Canada - National Science Library

    Nur Hishaam Sulaiman; Mohd Khairul Amri Kamarudin; Mohd Ekhwan Toriman; Hafizan Juahir; Frankie Marcus Ata; Azman Azid; Noor Jima Abd Wahab; Roslan Umar; Saiful iskandar Khalit; Mokhairi Makhtar; Amal Arfan; Uca Sideng

    2017-01-01

    .... This article discusses about the relationship of rainfall distribution and water level on major flood 2014 in Pahang River Basin, Malaysia in helping decision makers to flood management system...

  5. Impact of flood events on macrobenthic community structure on an intertidal flat developing in the Ohta River Estuary.

    Science.gov (United States)

    Nishijima, Wataru; Nakano, Yoichi; Nakai, Satoshi; Okuda, Tetsuji; Imai, Tsuyoshi; Okada, Mitsumasa

    2013-09-15

    We investigated the effects of river floods on the macrobenthic community of the intertidal flat in the Ohta River Estuary, Japan, from 2005 to 2010. Sediment erosion by flood events ranged from about 2-3 cm to 12 cm, and the salinity dropped to 0‰ even during low-intensity flood events. Cluster analysis of the macrobenthic population showed that the community structure was controlled by the physical disturbance, decreased salinity, or both. The opportunistic polychaete Capitella sp. was the most dominant species in all clusters, and populations of the long-lived polychaete Ceratonereis erythraeensis increased in years with stable flow and almost disappeared in years with intense flooding. The bivalve Musculista senhousia was also an important opportunistic species that formed mats in summer of the stable years and influenced the structure of the macrobenthic community. Our results demonstrate the substantial effects of flood events on the macrobenthic community structure.

  6. Influence of El Niño-Southern Oscillation (ENSO) on the behavior of floods in the Itajaí River basin in Southern Brazil

    Science.gov (United States)

    Tiago Silva, Artur; Portela, Maria Manuela; Naghettini, Mauro; Fernandes, Wilson

    2016-04-01

    The Itajaí River basin is located in the Southeastern South America (SESA) region, where the influence of El Niño-Southern Oscillation (ENSO) on hydrometeorological extremes has been reported. The lower reaches of the river are prone to calamitous floods as the basin is frequently subjected to extreme rainfall events. The history of devastating floods motivated the construction of detention dams in the upper reaches of the river during the 1970s-1990s. This work presents a study on the nonstationarity of floods in the Itajaí River, using a peaks-over-threshold (POT) approach applied to flood data from 3 gauging stations located in the Basin. Exploratory data analysis methods and nonstationary Poisson-Generalized Pareto models are used to study the joint influence of ENSO and upstream flood control dams on the flood regime of the river. Bayesian model estimation techniques are used with prior belief about the Generalized Pareto shape parameter elicited from regional information. The analysis revealed that occurrence rate and over-threshold peak magnitudes exhibit statistically significant and complex relationships with ENSO. Results also show evidence that, while upstream flood detention dams play a perceptible, though small, role in reducing flood hazard, the influence of the climate covariate on the flood regime is dominant. Furthermore, increased ENSO activity in recent decades, possibly related to a reported climate regime shift in the mid-1970s, has increased flood hazard and led to the occurrence of very large annual floods.

  7. Floods simulation in the Crişul Alb River Basin using hydrological model CONSUL

    Science.gov (United States)

    Mic, Rodica Paula; Corbus, Ciprian; Matreata, Marius

    2016-04-01

    For the simulation of floods, in the Crişul Alb River Basin, Romanian hydrological model CONSUL with lumped parameters was used. This deterministic mathematical rainfall-runoff model compute discharge hydrographs on configured river sub-basins, their channel routing and composition on the main river and tributaries and finally their routing and mitigation through reservoirs, according to the schematic representation (topological modelling) of how water flows and integrate in a river basin. After topological modelling 42 sub-basins and 19 river reaches resulted for the Crişul Alb River Basin model configuration, established according to the position of tributaries, hydrometric stations and reservoirs that influence flow. The CONSUL model used as input data, for each sub-basin, average values of precipitation and air temperature determined based on the measured values of weather stations in the basin. Calculation of average values was performed using a pre-processing program of meteorological data from rectangular grid nodes corresponding to Crişul Alb River Basin, averaging being achieved as weighted values based on the representativeness of these nodes for each analyzed sub-basin. Calibration of model parameters was performed by the simulation of 25 rainfall-runoff events from the period 1975 - 2010, chosen to cover a wide range of possible situations in the case of floods formation. By simulating floods from the hydrometric stations located in the closing sections of river sub-basins were determined the infiltration and unit hydrograph parameters and by simulating floods from the hydrometric stations located in the downstream sections of the river reaches hydrometrically controlled were determined the routing equation parameters. The parameters thus determined allow building some generalization relationships of these parameters according to the morphometric characteristics of the river sub-basins (surface, slope) or river reaches (length, slope). Based on these

  8. Upper and Lower Hamburg Bend 2011 Flood Evaluation on the Missouri River near Hamburg, Iowa

    Science.gov (United States)

    2017-01-01

    ER D C/ CH L TR -1 7- 1 Upper and Lower Hamburg Bend 2011 Flood Evaluation on the Missouri River near Hamburg, Iowa Co as ta l a nd H...Hamburg Bend 2011 Flood Evaluation on the Missouri River near Hamburg, Iowa Nathan Clifton and David Abraham Coastal and Hydraulics Laboratory... flood event. The evaluation required numerical hydrodynamic modeling of a pre-2011 flood condition of the entire floodplain and main channel with

  9. Dynamic Critical Rainfall-Based Flash Flood Early Warning and Forecasting for Medium-Small Rivers

    Science.gov (United States)

    Liu, Z.; Yang, D.; Hu, J.

    2012-04-01

    China is extremely frequent food disasters hit countries, annual flood season flash floods triggered by rainfall, mudslides, landslides have caused heavy casualties and property losses, not only serious threaten the lives of the masses, but the majority of seriously restricting the mountain hill areas of economic and social development and the people become rich, of building a moderately prosperous society goals. In the next few years, China will focus on prevention and control area in the flash flood disasters initially built "for the surveillance, communications, forecasting, early warning and other non-engineering measure based, non-engineering measures and the combinations of engineering measures," the mitigation system. The latest progresses on global torrential flood early warning and forecasting techniques are reviewed in this paper, and then an early warning and forecasting approach is proposed on the basis of a distributed hydrological model according to dynamic critical rainfall index. This approach has been applied in Suichuanjiang River basin in Jiangxi province, which is expected to provide valuable reference for building a national flash flood early warning and forecasting system as well as control of such flooding.

  10. Response of flood discharging capacity to the deterioration of the lower Yellow River

    Institute of Scientific and Technical Information of China (English)

    LI; Wenxue; LI; Yong; YAO; Wenyi; SU; Yunqi; ZHANG; Xiaohua

    2004-01-01

    Based on the clarifications of the deterioration characteristics of the lower Yellow River (LYR), the influence of river deterioration on flood discharging capacity is studied through theoretical derivation and analysis of field data. This study indicates that response of flood discharging capacity to river deterioration is nonlinear. Sediment depositions in the main channel cause the reductions of dominant discharge and thus the increase of initial flood stage. Reductions in the channel width result in the increases of the rising rate of flood stage and the decrease of flood discharging capacity.

  11. Flood Hazard Mapping by Using Geographic Information System and Hydraulic Model: Mert River, Samsun, Turkey

    Directory of Open Access Journals (Sweden)

    Vahdettin Demir

    2016-01-01

    Full Text Available In this study, flood hazard maps were prepared for the Mert River Basin, Samsun, Turkey, by using GIS and Hydrologic Engineering Centers River Analysis System (HEC-RAS. In this river basin, human life losses and a significant amount of property damages were experienced in 2012 flood. The preparation of flood risk maps employed in the study includes the following steps: (1 digitization of topographical data and preparation of digital elevation model using ArcGIS, (2 simulation of flood lows of different return periods using a hydraulic model (HEC-RAS, and (3 preparation of flood risk maps by integrating the results of (1 and (2.

  12. LONG-TERM EFFECTS OF THE GEZHOUBA PROJECT ON FLOOD PROPAGATION IN THE YANGTZE RIVER

    Institute of Scientific and Technical Information of China (English)

    Yaohua DONG; Ruilan YIN

    2001-01-01

    Based on hydrographs of "81.7" flood and topographies of 1980 and 1993, a 1-D mathematical model of flood is developed to study the effects of the Gezhouba Project on flood propagation along the Yichang-Jianli river reaches in the Yangtze River. Calculations and analysis show that, after 13 years' operation of the Gezhouba Project, the flood peak stages have been lowered, the flood curves of stage-discharge relationship have been moved, however, the effects on the flood discharges and storages can be neglected relatively.

  13. The Trend and Fluctuation of Historical Floods in the Middle Reaches of the Yangtze River

    Institute of Scientific and Technical Information of China (English)

    Wu Yi-jin; William A. Gough; Jiang Tong; Wang Xue-lei; Jin Wei-bin

    2003-01-01

    The middle reaches of the Yangtze River are the worst flood area of the whole basin. To study the variation regulation of the floods in this area over a long historical period assure improvement in predictions of floods in the region. The trend of flood occurred frequency has close relationship with human activities near the river. By using statistics analysis, the fluctuations for the time series of floods since 1525 are studied. The results show that the main cycle of flood variation can be identified obviously the period of 2, 8 and 40 years with exceeding the level of confidence 0.03.

  14. The Trend and Fluctuation of Historical Floods in the Middle Reaches of the Yangtze River

    Institute of Scientific and Technical Information of China (English)

    Wu; Yi-jin; William; A.Gough; 等

    2003-01-01

    The middle reaches of the Yangtze River are the worst flood area of the whole basin. To study the variation regulation of the floods in this area over a long historical period assure improvment in predictions of floods in the region.The trend of flood occurred frequency has close relationship with human activities near the river. By using statistics analysis, the fluctuations for the time series of floods since 1525 are studied. The results show that the main cycle of flood variation can be identified obviously the period of 2,8 and 40 years with exceeding the level of confidance 0.03.

  15. THE FLASH FLOODS ANALYSIS, REPRESENTATIVE FOR NIRAJ RIVER BETWEEN 1970-2008

    Directory of Open Access Journals (Sweden)

    ROŞCA SANDA

    2011-03-01

    Full Text Available The flash floods analysis, representative for Niraj River between 1970-2008. The need to know the characteristics of the flash floods is derived from the number and the intensity of floods occurred in the drainage basin of the Niraj river. Therefore, there were analyzed only the flash floods representatives for the years: 1970, 1995, 1998, 2001, 2008.The classification of the floods was realized according to the genesis and the flash flood hydrograph shape for the period 1970-2008, before and after the completion of the drainage basin planning/management depending on climatic, morphometric and morphological factors.

  16. 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

    ratio between post-flood and pre-flood width presents an average value of 4.2, with a maximum approaching 20. In the main river channels, due to the presence of wider sections and lower slope, the ratio resulted < 5, on average 1.3. The analysis of width ratio vs. flood peak unit stream power shows that the minimum unit stream power required to cause relevant widening was about 500 Wm-2. Nonetheless, some reaches affected by unit stream power as high as 4,000 Wm-2 exhibited limited or no widening at all. Indeed, a statistical analysis on the relationship between widening and both morphological and hydraulic controlling factors indicates that unit stream power and confinement index were the most relevant variables, whereas sediment input from mass wasting processes seems to have a localized influence. Remarkably, the analysis of subset referring to Trebbia and Nure basins showed that channel widening is strongly associated to bed aggradation, and that steeper tributaries underwent higher aggradation despite their larger sediment transport capacity. These results points out that geomorphic changes due to large floods are controlled by several factors that induce a highly variable pattern of change even within the same river basin.

  17. Influences on flood frequency distributions in Irish river catchments

    Science.gov (United States)

    Ahilan, S.; O'Sullivan, J. J.; Bruen, M.

    2012-04-01

    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 the

  18. 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

  19. Flood trends and variability in the Mekong river

    Directory of Open Access Journals (Sweden)

    J. M. Delgado

    2010-03-01

    Full Text Available Annual maximum discharge is analyzed in the Mekong river in Southeast Asia with regard to trends in average flood and trends in variability during the 20th century. Data from four gauging stations downstream of Vientiane, Laos, were used, covering two distinct hydrological regions within the Mekong basin. These time series span through over 70 years and are the longest daily discharge time series available in the region. The methods used, Mann Kendal test (MK, ordinary least squares with resampling (OLS and non-stationary generalized extreme value function (NSGEV, are first tested in a Monte Carlo experiment, in order to evaluate their detection power in presence of changing variance in the time series. The time series are generated using the generalized extreme value function with varying scale and location parameter. NSGEV outperforms MK and OLS, both because it resulted in less type II errors, but also because it allows for a more complete description of the trends, allowing to separate trends in average and in variability.

    Results from MK, OLS and NSGEV agreed on trends in average flood behaviour. However, the introduction of a time-varying scale parameter in the NSGEV allowed to isolate flood variability from the trend in average flood and to have a more complete view of the changes. Overall, results showed an increasing likelihood of extreme floods during the last half of the century, although the probability of an average flood decreased during the same period. A period of enhanced variance in the last quarter of the 20th century, estimated with the wavelet power spectrum as a function of time, was identified, which confirmed the results of the NSGEV.

    We conclude that the absence of detected positive trends in the hydrological time series was a methodological misconception due to over-simplistic models.

  20. Time Sequence on the Flash Flood Disaster in the Tsurugi River, Hofu City, in Japan

    Science.gov (United States)

    Yamakoshi, T.; Nakano, Y.; Ishizuka, T.; Tamura, K.; Hasegawa, Y.

    2012-04-01

    A rainstorm that hit Hofu city in Yamaguchi Prefecture, Japan on July 21st, 2009 caused flash floods or debris flows in many mountain streams around Hofu, claiming many lives and devastating downstream communities and the national highway. The authors investigated high water marks of the flash flood or debris flow after the devastating rainstorm and interviewed the eyewitnesses that were present during the disaster in order to determine the time sequence of the phenomenon that occurred in one mountainous torrent, the Tsurugi River. The results of the survey conducted so far suggest the following; 1) The peak discharge estimated from the high water marks is around 30 to 69 m3/s at the investigated cross section just downstream of the sediment control dam. It was consistent with a peak discharge value obtained by simple runoff analysis. 2) On the other hand, the estimated peak discharge was much larger than that obtained through the runoff analysis. This is probably because of the influence of the debris flow or hyper-concentrated flow from the tributaries downstream of the sediment control dams. 3) The flood discharge from the Tsurugi River to the national highway suddenly increased at the last moment of the rainstorm at 12:30. At the same time, the ponding behind the bridge of the highway seemed to occur. 4) Blocking of the river flow at the bridge hadn't occurred until around 12:00. However, it probably occurred at around 12:30 due to the occurrences of the debris flow or hyper-concentrated flow from the tributaries. These findings infer that the river channel of the Tsurugi River had succeeded in draining flood runoff until nearly the end of the rainstorm. At the last moment, however, occurrences of the debris flow or hyper-concentrated flow from the tributaries might result in the clogging of the bridge and the inundation.

  1. The flood control and regulation of Three Gorges Project

    Institute of Scientific and Technical Information of China (English)

    Cai Qihua

    2011-01-01

    The important role of Three Gorges Project (TGP) in the flood management of the Yangtze River Basin is summarized. The Optimal Regulation Schemes of the Three Gorge Reservoir is briefly described. The flood regulation effect of TGP is analyzed. Typical issues related to reservoir operation for flood regulation are discussed and suggestions are put forward for the future work.

  2. Linking the historic 2011 Mississippi River flood to coastal wetland sedimentation

    Science.gov (United States)

    Falcini, Federico; Khan, Nicole S.; Macelloni, Leonardo; Horton, Benjamin P.; Lutken, Carol B.; McKee, Karen L.; Santoleri, Rosalia; Colella, Simone; Li, Chunyan; Volpe, Gianluca; D'Emidio, Marco; Salusti, Alessandro; Jerolmack, Douglas J.

    2012-11-01

    Wetlands in the Mississippi River deltaic plain are deteriorating in part because levees and control structures starve them of sediment. In spring 2011 a record-breaking flood brought discharge on the lower Mississippi River to dangerous levels, forcing managers to divert up to 3,500m3s-1 of water to the Atchafalaya River Basin. Here we use field-calibrated satellite data to quantify differences in inundation and sediment-plume patterns between the Mississippi and Atchafalaya River. We assess the impact of these extreme outflows on wetland sedimentation, and use in situ data collected during the historic flood to characterize the Mississippi plume's hydrodynamics and suspended sediment. We show that a focused, high-momentum jet emerged from the leveed Mississippi, and delivered sediment far offshore. In contrast, the plume from the Atchafalaya was more diffuse; diverted water inundated a large area, and sediment was trapped within the coastal current. The largest sedimentation, of up to several centimetres, occurred in the Atchafalaya Basin despite the larger sediment load carried by the Mississippi. Sediment accumulation was lowest along the shoreline between the two river sources. We conclude that river-mouth hydrodynamics and wetland sedimentation patterns are mechanistically linked, providing results that are relevant for plans to restore deltaic wetlands using artificial diversions.

  3. Multisite flooding hazard assessment in the Upper Mississippi River

    Science.gov (United States)

    Ghizzoni, Tatiana; Roth, Giorgio; Rudari, Roberto

    2012-01-01

    SummaryThis contribution presents an assessment of the joint probability distribution able to describe multi-site multi-basin flood scenarios in a high dimensionality framework. This goal will be pursued through two different approaches: the multivariate skew- t distribution and the Student copula with arbitrary margins. While copulas have been widely used in the modeling of hydrological processes, the use of the skew- t distribution in hydrology has been only recently proposed with reference to a trivariate application (Ghizzoni et al., 2010, Adv. Water Resour., 33, 1243-1255). Both methods are here applied and discussed in a context of considerably higher dimensionality: the Upper Mississippi River floods. In fact, to enhance the characteristics of the correlation structure, eighteen nested and non-nested gauging stations were selected, with significantly different contributing areas. Such conditions represent a challenge for both the skew- t and the copula approach. In perspective, the ability of such approaches in explaining the multivariate aspects of the relevant processes is needed to specify flood hazard scenarios in terms of their intensity, extension and frequency. When this is associated to the knowledge of location, value and vulnerability of exposed elements, comprehensive flood risk scenarios can be produced, and risk cumuli quantified, for given portfolios, composed of wherever located risks.

  4. Atmospheric Rivers, Floods and the Water Resources of California

    Directory of Open Access Journals (Sweden)

    Daniel R. Cayan

    2011-03-01

    Full Text Available California’s highly variable climate and growing water demands combine to pose both water-supply and flood-hazard challenges to resource managers. Recently important efforts to more fully integrate the management of floods and water resources have begun, with the aim of benefitting both sectors. California is shown here to experience unusually large variations in annual precipitation and streamflow totals relative to the rest of the US, variations which mostly reflect the unusually small average number of wet days per year needed to accumulate most of its annual precipitation totals (ranging from 5 to 15 days in California. Thus whether just a few large storms arrive or fail to arrive in California can be the difference between a banner year and a drought. Furthermore California receives some of the largest 3-day storm totals in the country, rivaling in this regard the hurricane belt of the southeastern US. California’s largest storms are generally fueled by landfalling atmospheric rivers (ARs. The fractions of precipitation and streamflow totals at stations across the US that are associated with ARs are documented here and, in California, contribute 20–50% of the state’s precipitation and streamflow. Prospects for long-lead forecasts of these fractions are presented. From a meteorological perspective, California’s water resources and floods are shown to derive from the same storms to an extent that makes integrated flood and water resources management all the more important.

  5. The Iowa Flood Center's River Stage Sensors—Technical Details

    Science.gov (United States)

    Niemeier, J. J.; Kruger, A.; Ceynar, D.; Fahim Rezaei, H.

    2012-12-01

    The Iowa Flood Center (IFC), along with support from the Iowa Department of Transportation (DOT) and the Iowa Department of Natural Resources (DNR) have developed a bridge-mounted river stage sensor. Each sensor consists of an ultrasonic distance measuring module, cellular modem, a GPS unit that provides accurate time and an embedded controller that orchestrates the sensors' operation. A sensor is powered by a battery and solar panel along with a solar charge controller. All the components are housed in/on a sturdy metal box that is then mounted on the side of a bridge. Additionally, each sensor incorporates a water-intrusion sensor and an internal temperature sensor. In operation, the microcontroller wakes, and turns on the electronics every 15 minutes and then measures the distance between the ultrasonic sensor and the water surface. Several measurements are averaged and transmitted along with system health information (battery voltage, state of water intrusion sensor, and internal temperature) via cellular modem to remote servers on the internet. The microcontroller then powers the electronics down and enters a sleep/power savings mode. The sensor's firmware allows the remote server to adjust the measurement rate to 5, 15, and 60 minutes. Further, sensors maintain a 24-day buffer of previous measurements. If a sensor could not successfully transmit its data because of cellular network connection problems, it will transmit the backlog on subsequent transmissions. We paid meticulous attention to all engineering aspects and sensors are very robust and have operated essentially continuously through two Iowa winters and summers, including the 2012 record-breaking warm summer.

  6. Taming the Mighty Mississippi: Integrating paleo-flood data and modeling to understand the patterns and causes of extreme floods on a major river system

    Science.gov (United States)

    Munoz, Samuel; Giosan, Liviu; Jeffrey, Donnelly; Dee, Sylvia; Shen, Zhixiong

    2016-04-01

    The Mississippi River is an economic artery of the United States that is heavily managed to provide flood control and maintain a navigable shipping channel. The current system of levees and spillway structures was conceived in the early 20th century, but the ability of this system to withstand the altered hydroclimatic conditions projected for the next century is poorly understood. Here, we present initial results from a project that integrates new sedimentary records from floodplain lakes with analyses of sediment geochemistry and climate model simulations to better understand the causes of extreme floods on the lower Mississippi River. In our sedimentary paleoflood records, flood event beds are characterized by an upward fining sequence from deposition of the bedload and suspended load during overbank floods, identified here using high-resolution laser particle-size analysis and elemental composition (XRF), and dated using radioisotopes (137Cs, 210Pb, 14C) and optically-stimulated luminescence (OSL) on quartz. Grain-size descriptors and elemental ratios of Zr/Fe and Fe/Rb are highly correlated, and are used alongside historical discharge records to develop a statistical model for reconstructing flood magnitude in prehistoric contexts. Geochemical analyses of sediments from the floodplains of major tributaries of the Mississippi are used to assess the systematics of 87Sr/86Sr, 143Nd/144Nd, 206Pb/204Pb, and 208Pb/204Pb across the basin, enabling identification of the synoptic patterns of individual paleo-flood events. We investigate the dynamical drivers of past floods on the lower Mississippi using both reanalysis data and the last millennium simulation from NCAR model CESM1 to find that increased likelihoods of extreme floods on the lower Mississippi River are associated with enhanced moisture flux over midcontinental North America that is controlled by the interaction of seasonally variable soil moisture over major tributaries with inter-annual (e.g., ENSO) and

  7. Flood forecasting for River Mekong with data-based models

    Science.gov (United States)

    Shahzad, Khurram M.; Plate, Erich J.

    2014-09-01

    In many regions of the world, the task of flood forecasting is made difficult because only a limited database is available for generating a suitable forecast model. This paper demonstrates that in such cases parsimonious data-based hydrological models for flood forecasting can be developed if the special conditions of climate and topography are used to advantage. As an example, the middle reach of River Mekong in South East Asia is considered, where a database of discharges from seven gaging stations on the river and 31 rainfall stations on the subcatchments between gaging stations is available for model calibration. Special conditions existing for River Mekong are identified and used in developing first a network connecting all discharge gages and then models for forecasting discharge increments between gaging stations. Our final forecast model (Model 3) is a linear combination of two structurally different basic models: a model (Model 1) using linear regressions for forecasting discharge increments, and a model (Model 2) using rainfall-runoff models. Although the model based on linear regressions works reasonably well for short times, better results are obtained with rainfall-runoff modeling. However, forecast accuracy of Model 2 is limited by the quality of rainfall forecasts. For best results, both models are combined by taking weighted averages to form Model 3. Model quality is assessed by means of both persistence index PI and standard deviation of forecast error.

  8. Terrace aggradation during the 1978 flood on Powder River, Montana, USA

    Science.gov (United States)

    Moody, J.A.; Meade, R.H.

    2008-01-01

    Flood processes no longer actively increase the planform area of terraces. Instead, lateral erosion decreases the area. However, infrequent extreme floods continue episodic aggradation of terraces surfaces. We quantify this type of evolution of terraces by an extreme flood in May 1978 on Powder River in southeastern Montana. Within an 89-km study reach of the river, we (1) determine a sediment budget for each geomorphic feature, (2) interpret the stratigraphy of the newly deposited sediment, and (3) discuss the essential role of vegetation in the depositional processes. Peak flood discharge was about 930??m3 s- 1, which lasted about eight??days. During this time, the flood transported 8.2??million tons of sediment into and 4.5??million tons out of the study reach. The masses of sediment transferred between features or eroded from one feature and redeposited on the same feature exceeded the mass transported out of the reach. The flood inundated the floodplain and some of the remnants of two terraces along the river. Lateral erosion decreased the planform area of the lower of the two terraces (~ 2.7??m above the riverbed) by 3.2% and that of the higher terrace (~ 3.5??m above the riverbed) by 4.1%. However, overbank aggradation, on average, raised the lower terrace by 0.16??m and the higher terrace by 0.063??m. Vegetation controlled the type, thickness, and stratigraphy of the aggradation on terrace surfaces. Two characteristic overbank deposits were common: coarsening-upward sequences and lee dunes. Grass caused the deposition of the coarsening-upward sequences, which had 0.02 to 0.07??m of mud at the base, and in some cases, the deposits coarsened upwards to coarse sand on the top. Lee dunes, composed of fine and very fine sand, were deposited in the wake zone downstream from the trees. The characteristic morphology of the dunes can be used to estimate some flood variables such as suspended-sediment particle size, minimum depth, and critical shear velocity

  9. Effects of global warming on floods and droughts and related water quality of rivers

    NARCIS (Netherlands)

    De Jong, B.

    2006-01-01

    This review focuses on the effect of global warming on droughts, rainstorms and floods and related water quality of rivers. Relations of temperature, rainstorms and river discharges with water quality variables like water temperature, chemical concentrations and microbiological activity are

  10. Flooding On

    Institute of Scientific and Technical Information of China (English)

    YIN PUMIN

    2010-01-01

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

  11. Estimated flood-inundation mapping for the Lower Blue River in Kansas City, Missouri, 2003-2005

    Science.gov (United States)

    Kelly, Brian P.; Rydlund, Paul H.

    2006-01-01

    The U.S. Geological Survey, in cooperation with the city of Kansas City, Missouri, began a study in 2003 of the lower Blue River in Kansas City, Missouri, from Gregory Boulevard to the mouth at the Missouri River to determine the estimated extent of flood inundation in the Blue River valley from flooding on the lower Blue River and from Missouri River backwater. Much of the lower Blue River flood plain is covered by industrial development. Rapid development in the upper end of the watershed has increased the volume of runoff, and thus the discharge of flood events for the Blue River. Modifications to the channel of the Blue River began in late 1983 in response to the need for flood control. By 2004, the channel had been widened and straightened from the mouth to immediately downstream from Blue Parkway to convey a 30-year flood. A two-dimensional depth-averaged flow model was used to simulate flooding within a 2-mile study reach of the Blue River between 63rd Street and Blue Parkway. Hydraulic simulation of the study reach provided information for the design and performance of proposed hydraulic structures and channel improvements and for the production of estimated flood-inundation maps and maps representing an areal distribution of water velocity, both magnitude and direction. Flood profiles of the Blue River were developed between Gregory Boulevard and 63rd Street from stage elevations calculated from high water marks from the flood of May 19, 2004; between 63rd Street and Blue Parkway from two-dimensional hydraulic modeling conducted for this study; and between Blue Parkway and the mouth from an existing one-dimensional hydraulic model by the U.S. Army Corps of Engineers. Twelve inundation maps were produced at 2-foot intervals for Blue Parkway stage elevations from 750 to 772 feet. Each map is associated with National Weather Service flood-peak forecast locations at 63rd Street, Blue Parkway, Stadium Drive, U.S. Highway 40, 12th Street, and the Missouri River

  12. Wetland hydrology and tree distribution of the Apalachicola River flood plain, Florida

    Science.gov (United States)

    Leitman, Helen M.; Sohm, James E.; Franklin, Marvin A.

    1984-01-01

    The Apalachicola River in northwest Florida is part of a three-State drainage basin encompassing 50,800 km 2 in Alabama, Georgia, and Florida. The river is formed by the confluence of the Chattahoochee and Flint Rivers at Jim Woodruff Dam from which it flows 171 km to Apalachicola Bay in the Gulf of Mexico. Its average annual discharge at Chattahoochee, Fla., is 690 m3/s (1958-80) with annual high flows averaging nearly 3,000 m3/s. Its flood plain supports 450 km 2 of bottom-land hardwood and tupelo-cypress forests. The Apalachicola River Quality Assessment focuses on the hydrology and productivity of the flood-plain forest. The purpose of this part of the assessment is to address river and flood-plain hydrology, flood-plain tree species and forest types, and water and tree relations. Seasonal stage fluctuations in the upper river are three times greater than in the lower river. Analysis of long-term streamflow record revealed that 1958-79 average annual and monthly flows and flow durations were significantly greater than those of 1929-57, probably because of climatic changes. However, stage durations for the later period were equal to or less than those of the earlier period. Height of natural riverbank levees and the size and distribution of breaks in the levees have a major controlling effect on flood-plain hydrology. Thirty-two kilometers upstream of the bay, a flood-plain stream called the Brothers River was commonly under tidal influence during times of low flow in the 1980 water year. At the same distance upstream of the bay, the Apalachicola River was not under tidal influence during the 1980 water year. Of the 47 species of trees sampled, the five most common were wet-site species constituting 62 percent of the total basal area. In order of abundance, they were water tupelo, Ogeechee tupelo, baldcypress, Carolina ash, and swamp tupelo. Other common species were sweetgum, overcup oak, planertree, green ash, water hickory, sugarberry, and diamond-leaf oak

  13. Establishment of Brazos River Flood Event Layer Proxies for Paleoclimate Reconstruction and Flood Layer Preservation on the Texas Continental Shelf

    Science.gov (United States)

    McGuffin, A. B.; Carlin, J. A.; Dellapenna, T.

    2016-12-01

    The Brazos River, which empties into the Gulf of Mexico along the central Texas coast, is strongly modulated by the El Niño-Southern Oscillation (ENSO), with drought conditions during La Niña periods, and flood conditions during El Niño periods. During the most recent strong ENSO in 2015-2016, Texas experienced record rainfall, resulting in record discharge and flooding of the Brazos River. Since 1967 most of the large floods on the Brazos River have corresponded to ENSO events, thus the purpose of this study is to track the 2015-1016 Brazos River flood deposits on the continental shelf to develop a proxy for strong ENSO events in the northwestern Gulf of Mexico. Between June 2015 and July 2016, six offshore sampling trips have been conducted at the mouth of the river, along the dispersal pathway, and at what is believed to be the ultimate sink, the Texas Mud Blanket (TMB), a mid-shelf mud deposit roughly 75 km downdrift of the river mouth. A total of 33 short gravity cores, 36 box cores, and two vibracores were collected from the area, and were imaged using X-ray radiography, and analyzed for grain size, porosity and 7Be activity. The short gravity cores and box cores were collected proximal to the mouth of the Brazos River and were used to delineate the flood deposit and create a time series of flood event sediment dispersal. Flood event deposits have been identified as clay-rich, homogeneous packages with 50-80% water content. Deposits range between 2-10 cm thick and have been found up to 12 km off the coast. 7Be activity of dry bulk sediment was measured in one vibracore from the TMB and detected up to 8 cm deep. The Brazos River is the only fluvial source in the region and elevated 7Be inventories therefore suggest Brazos River flood event sediment is deposited in the TMB. Comparisons between proximal Brazos River sediment core radiographs and TMB vibracore radiographs preliminarily suggest preservation of flood event layers in the TMB. Additional short

  14. The influence of flood frequency, riparian vegetation and threshold on long-term river transport capacity

    Science.gov (United States)

    Croissant, Thomas; Lague, Dimitri; Davy, Philippe

    2016-04-01

    Climate fluctuations at geological timescales control the capacity of rivers to transport sediment with consequences on geochemical cycles, sedimentary basins dynamics and sedimentation/tectonics interactions. While the impact of differential friction generated by riparian vegetation has been studied for individual flood events, its impact on the long-term sediment transport capacity of rivers, modulated by the frequency of floods remains unknown. Here, we investigate this effect on a simplified river-floodplain configuration obeying observed hydraulic scaling laws. We numerically integrate the full-frequency magnitude distribution of discharge events and its impact on the transport capacity of bedload and suspended material for various level of vegetation-linked differential friction. We demonstrate that riparian vegetation by acting as a virtual confinement of the flow i) increases significantly the instantaneous transport capacity of the river independently of the transport mode and ii) increases the long term bedload transport rates as a function of discharge variability. Our results expose the dominance of flood frequency rather than riparian vegetation on the long term sediment transport capacity. Therefore, flood frequency has to be considered when evaluating long-term bedload transport capacity while floodplain vegetation is important only in high discharge variability regimes. By comparing the transport capacity of unconfined alluvial rivers and confined bedrock gorges, we demonstrate that the latter always presents the highest long term transport capacity at equivalent width and slope. The loss of confinement at the transition between bedrock and alluvial river must be compensated by a widening or a steepening of the alluvial channel to avoid infinite storage. Because steepening is never observed in natural system, we compute the alluvial widening factor value that varies between 3 to 11 times the width of the bedrock channel depending on riparian

  15. Concentrations and transport of suspended sediment, nutrients, and pesticides in the lower Mississippi-Atchafalaya River subbasin during the 2011 Mississippi River flood, April through July

    Science.gov (United States)

    Welch, Heather L.; Coupe, Richard H.; Aulenbach, Brent T.

    2014-01-01

    High streamflow associated with the April–July 2011 Mississippi River flood forced the simultaneous opening of the three major flood-control structures in the lower Mississippi-Atchafalaya River subbasin for the first time in history in order to manage the amount of water moving through the system. The U.S. Geological Survey (USGS) collected samples for analysis of field properties, suspended-sediment concentration, particle-size, total nitrogen, nitrate plus nitrite, total phosphorus, orthophosphate, and up to 136 pesticides at 11 water-quality stations and 2 flood-control structures in the lower Mississippi-Atchafalaya River subbasin from just above the confluence of the upper Mississippi and Ohio Rivers downstream from April through July 2011. Monthly fluxes of suspended sediment, suspended sand, total nitrogen, nitrate plus nitrite, total phosphorus, orthophosphate, atrazine, simazine, metolachlor, and acetochlor were estimated at 9 stations and 2 flood-control structures during the flood period. Although concentrations during the 2011 flood were within the range of what has been observed historically, concentrations decreased during peak streamflow on the lower Mississippi River. Prior to the 2011 flood, high concentrations of suspended sediment and nitrate were observed in March 2011 at stations downstream of the confluence of the upper Mississippi and Ohio Rivers, which probably resulted in a loss of available material for movement during the flood. In addition, the major contributor of streamflow to the lower Mississippi-Atchafalaya River subbasin during April and May was the Ohio River, whose water contained lower concentrations of suspended sediment, pesticides, and nutrients than water from the upper Mississippi River. Estimated fluxes for the 4-month flood period were still quite high and contributed approximately 50 percent of the estimated annual suspended sediment, nitrate, and total phosphorus fluxes in 2011; the largest fluxes were estimated at

  16. Geomorphology and flood-plain vegetation of the Sprague and lower Sycan Rivers, Klamath Basin, Oregon

    Science.gov (United States)

    O'Connor, James E.; McDowell, Patricia F.; Lind, Pollyanna; Rasmussen, Christine G.; Keith, Mackenzie K.

    2015-01-01

    This study provides information on channel and flood-plain processes and historical trends to guide effective restoration and monitoring strategies for the Sprague River Basin, a primary tributary (via the lower Williamson River) of Upper Klamath Lake, Oregon. The study area covered the lower, alluvial segments of the Sprague River system, including the lower parts of the Sycan River, North Fork Sprague River, South Fork Sprague River, and the entire main-stem Sprague River between the confluence of the North Fork Sprague and the South Fork Sprague Rivers and its confluence with the Williamson River at Chiloquin, Oregon. The study included mapping and stratigraphic analysis of flood-plain deposits and flanking features; evaluation of historical records, maps and photographs; mapping and analysis of flood-plain and channel characteristics (including morphologic and vegetation conditions); and a 2006 survey of depositional features left by high flows during the winter and spring of 2005–06.

  17. Impacts of the 2016 outburst flood on the Bhote Koshi River valley, central Nepal

    Science.gov (United States)

    Cook, Kristen; Andermann, Christoff; Gimbert, Florent; Hovius, Niels; Adhikari, Basanta

    2017-04-01

    The central Nepal Himalaya is a region of rapid erosion where fluvial processes are largely driven by the annual Indian Summer Monsoon, which delivers up to several meters of precipitation each year. However, the rivers in this region are also subject to rare catastrophic floods caused by the sudden failure of landslide or moraine dams. Because these floods happen rarely, it has been difficult to isolate their impact on the rivers and adjacent hillslopes, and their importance for the long-term evolution of Himalayan rivers is poorly constrained. On the 5th of July, 2016, the Bhote Koshi River in central Nepal was hit by a glacial lake outburst flood (GLOF). The flood passed through a seismic and hydrological observatory installed along the river in June 2015, and we have used the resulting data to constrain the timing, duration, and bedload transport properties of the outburst flood. The impact of the flood on the river can be further observed with hourly time-lapse photographs, daily measurements of suspended sediment load, repeat lidar surveys, and satellite imagery. Overall, our observatory data span two monsoon seasons, allowing us to evaluate the impacts of the outburst flood relative to the annual monsoon flood. The outburst flood affected the river on several timescales. In the short term, it transported large amounts of coarse sediment and restructured the river bed during the hours of the flood pulse itself. Over intermediate timescales it resulted in elevated bedload and suspended load transport for several weeks following the flood. Over longer timescales the flood undercut and destabilized the river banks and hillslopes in a number of locations, leading to bank collapses, slumps, and landslides. We map changes in the channel and associated mass wasting using rapidEye imagery from Oct. 2015 and Oct. 2016. We also use repeat terrestrial lidar scans to quantify the magnitude of change in multiple locations along the river channel and to measure bank

  18. Floods of Ohio and Mississippi Rivers, January-February 1937, with a section on the Flood deposits of the Ohio River, January-February 1937

    Science.gov (United States)

    Grover, Nathan Clifford; Mansfield, George Rogers

    1938-01-01

    In January and February 1937 the Ohio and mid-Mississippi Rivers experienced floods which, over reaches many hundreds of miles in length, exceeded all previously recorded stages. When measured by the loss of life and property, extent of damage, and general disruption of human activities, these floods constituted a major catastrophe.

  19. D GIS for Flood Modelling in River Valleys

    Science.gov (United States)

    Tymkow, P.; Karpina, M.; Borkowski, A.

    2016-06-01

    The objective of this study is implementation of system architecture for collecting and analysing data as well as visualizing results for hydrodynamic modelling of flood flows in river valleys using remote sensing methods, tree-dimensional geometry of spatial objects and GPU multithread processing. The proposed solution includes: spatial data acquisition segment, data processing and transformation, mathematical modelling of flow phenomena and results visualization. Data acquisition segment was based on aerial laser scanning supplemented by images in visible range. Vector data creation was based on automatic and semiautomatic algorithms of DTM and 3D spatial features modelling. Algorithms for buildings and vegetation geometry modelling were proposed or adopted from literature. The implementation of the framework was designed as modular software using open specifications and partially reusing open source projects. The database structure for gathering and sharing vector data, including flood modelling results, was created using PostgreSQL. For the internal structure of feature classes of spatial objects in a database, the CityGML standard was used. For the hydrodynamic modelling the solutions of Navier-Stokes equations in two-dimensional version was implemented. Visualization of geospatial data and flow model results was transferred to the client side application. This gave the independence from server hardware platform. A real-world case in Poland, which is a part of Widawa River valley near Wroclaw city, was selected to demonstrate the applicability of proposed system.

  20. 3D GIS FOR FLOOD MODELLING IN RIVER VALLEYS

    Directory of Open Access Journals (Sweden)

    P. Tymkow

    2016-06-01

    Full Text Available The objective of this study is implementation of system architecture for collecting and analysing data as well as visualizing results for hydrodynamic modelling of flood flows in river valleys using remote sensing methods, tree-dimensional geometry of spatial objects and GPU multithread processing. The proposed solution includes: spatial data acquisition segment, data processing and transformation, mathematical modelling of flow phenomena and results visualization. Data acquisition segment was based on aerial laser scanning supplemented by images in visible range. Vector data creation was based on automatic and semiautomatic algorithms of DTM and 3D spatial features modelling. Algorithms for buildings and vegetation geometry modelling were proposed or adopted from literature. The implementation of the framework was designed as modular software using open specifications and partially reusing open source projects. The database structure for gathering and sharing vector data, including flood modelling results, was created using PostgreSQL. For the internal structure of feature classes of spatial objects in a database, the CityGML standard was used. For the hydrodynamic modelling the solutions of Navier-Stokes equations in two-dimensional version was implemented. Visualization of geospatial data and flow model results was transferred to the client side application. This gave the independence from server hardware platform. A real-world case in Poland, which is a part of Widawa River valley near Wroclaw city, was selected to demonstrate the applicability of proposed system.

  1. FLOOD MODELING OF THE VUKA RIVER SECTION UPSTREAM OF ITS CONFLUENCE WITH THE DANUBE RIVER

    Directory of Open Access Journals (Sweden)

    Dario Marić

    2016-12-01

    Full Text Available In this paper, a section of the Vuka River from its confluence with the Danube River in Vukovar to 3 + 630 rkm was modeled. The possibility and size of floods in the surrounding area were analyzed for different return periods (2, 5, 10, 50, and 100 yrs. Although the high-water levels of the Danube River are lower than the terrain elevation of Vukovar, they cause backwater in the Vuka River and in its tributary, the Bobotski canal. In that indirect way, the surrounding area is endangered and the efficiency of drainage systems is reduced. The existing riverbed of the analyzed Vuka River section was digitalized based on a digital terrain model using the geographic information system (GIS software ArcGIS and the HEC-GeoRAS toolbar. A mathematical model of the steady-state flow of the Vuka river section using the digitized riverbed was executed in the HEC-RAS software using different return periods. The obtained velocities and water levels were analyzed using HEC-RAS, and the sizes of the flooded areas were calculated and observed in ArcGIS.

  2. River discharge and flood inundation over the Amazon based on IPCC AR5 scenarios

    Science.gov (United States)

    Paiva, Rodrigo; Sorribas, Mino; Jones, Charles; Carvalho, Leila; Melack, John; Bravo, Juan Martin; Beighley, Edward

    2015-04-01

    Climate change and related effects over the hydrologic regime of the Amazon River basin could have major impacts over human and ecological communities, including issues with transportation, flood vulnerability, fisheries and hydropower generation. We examined future changes in discharge and floodplain inundation within the Amazon River basin. We used the hydrological model MGB-IPH (Modelo de Grandes Bacias - Instituto de Pesquisas Hidráulicas) coupled with a 1D river hydrodynamic model simulating water storage over the floodplains. The model was forced using satellite based precipitation from the TRMM 3B42 dataset, and it had a good performance when validated against discharge and stage measurements as well as remotely sensed data, including radar altimetry-based water levels, gravity anomaly-based terrestrial water storage and flood inundation extent. Future scenarios of precipitation and other relevant climatic variables for the 2070 to 2100 time period were taken from five coupled atmosphere-ocean general circulation models (AOGCMs) from IPCC's Fifth Assessment Report (AR5) Coupled Model Intercomparison Project Phase 5 (CMIP5). The climate models were chosen based on their ability to represent the main aspects of recent (1970 to 2000) Amazon climate. A quantile-quantile bias removal procedure was applied to climate model precipitation to mitigate unreliable predictions. The hydrologic model was then forced using past observed climate data altered by delta change factors based on the past and future climate models aiming to estimate projected discharge and floodplain inundation in climate change scenario at several control points in the basin. The climate projections present large uncertainty, especially the precipitation rate, and predictions using different climate models do not agree on the sign of changes on total Amazon flood extent or discharge along the main stem of the Amazon River. However, analyses of results at different regions indicate an increase

  3. Generalized Exponential Distribution in Flood Frequency Analysis for Polish Rivers

    Science.gov (United States)

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

    2015-01-01

    Many distributions have been used in flood frequency analysis (FFA) for fitting the flood extremes data. However, as shown in the paper, the scatter of Polish data plotted on the moment ratio diagram shows that there is still room for a new model. In the paper, we study the usefulness of the generalized exponential (GE) distribution in flood frequency analysis for Polish Rivers. We investigate the fit of GE distribution to the Polish data of the maximum flows in comparison with the inverse Gaussian (IG) distribution, which in our previous studies showed the best fitting among several models commonly used in FFA. Since the use of a discrimination procedure without the knowledge of its performance for the considered probability density functions may lead to erroneous conclusions, we compare the probability of correct selection for the GE and IG distributions along with the analysis of the asymptotic model error in respect to the upper quantile values. As an application, both GE and IG distributions are alternatively assumed for describing the annual peak flows for several gauging stations of Polish Rivers. To find the best fitting model, four discrimination procedures are used. In turn, they are based on the maximized logarithm of the likelihood function (K procedure), on the density function of the scale transformation maximal invariant (QK procedure), on the Kolmogorov-Smirnov statistics (KS procedure) and the fourth procedure based on the differences between the ML estimate of 1% quantile and its value assessed by the method of moments and linear moments, in sequence (R procedure). Due to the uncertainty of choosing the best model, the method of aggregation is applied to estimate of the maximum flow quantiles. PMID:26657239

  4. Generalized Exponential Distribution in Flood Frequency Analysis for Polish Rivers.

    Science.gov (United States)

    Markiewicz, Iwona; Strupczewski, Witold G; Bogdanowicz, Ewa; Kochanek, Krzysztof

    2015-01-01

    Many distributions have been used in flood frequency analysis (FFA) for fitting the flood extremes data. However, as shown in the paper, the scatter of Polish data plotted on the moment ratio diagram shows that there is still room for a new model. In the paper, we study the usefulness of the generalized exponential (GE) distribution in flood frequency analysis for Polish Rivers. We investigate the fit of GE distribution to the Polish data of the maximum flows in comparison with the inverse Gaussian (IG) distribution, which in our previous studies showed the best fitting among several models commonly used in FFA. Since the use of a discrimination procedure without the knowledge of its performance for the considered probability density functions may lead to erroneous conclusions, we compare the probability of correct selection for the GE and IG distributions along with the analysis of the asymptotic model error in respect to the upper quantile values. As an application, both GE and IG distributions are alternatively assumed for describing the annual peak flows for several gauging stations of Polish Rivers. To find the best fitting model, four discrimination procedures are used. In turn, they are based on the maximized logarithm of the likelihood function (K procedure), on the density function of the scale transformation maximal invariant (QK procedure), on the Kolmogorov-Smirnov statistics (KS procedure) and the fourth procedure based on the differences between the ML estimate of 1% quantile and its value assessed by the method of moments and linear moments, in sequence (R procedure). Due to the uncertainty of choosing the best model, the method of aggregation is applied to estimate of the maximum flow quantiles.

  5. Artificial Neural Networks (ANNs for flood forecasting at Dongola Station in the River Nile, Sudan

    Directory of Open Access Journals (Sweden)

    Sulafa Hag Elsafi

    2014-09-01

    Full Text Available Heavy seasonal rains cause the River Nile in Sudan to overflow and flood the surroundings areas. The floods destroy houses, crops, roads, and basic infrastructure, resulting in the displacement of people. This study aimed to forecast the River Nile flow at Dongola Station in Sudan using an Artificial Neural Network (ANN as a modeling tool and validated the accuracy of the model against actual flow. The ANN model was formulated to simulate flows at a certain location in the river reach, based on flow at upstream locations. Different procedures were applied to predict flooding by the ANN. Readings from stations along the Blue Nile, White Nile, Main Nile, and River Atbara between 1965 and 2003 were used to predict the likelihood of flooding at Dongola Station. The analysis indicated that the ANN provides a reliable means of detecting the flood hazard in the River Nile.

  6. The influence of flood pulse on fish communities of floodplain canals in the Middle Solimões River, Brazil

    Directory of Open Access Journals (Sweden)

    Raniere G. C. Sousa

    Full Text Available The functioning of large river systems with adjacent floodplains is strongly influenced by the flood pulse. This phenomenon is the main structuring force for the biota, including fish communities that use floodplain environments for spawning, feeding, nursery and refuge. In floodplains and in the entire basin, the volume of water controls internal flows. During rising water, the high discharge of the river acts as a natural barrier to the canals that connect floodplain lakes and the Solimões River, because the water flows from river to lake. During the dry period, there is a reduction of discharge and the water flow is reversed or stationary. These canals are environments with distinct ecological characteristics such as differentiated limnology and water level variation intensely affected by the hydrological cycle. Therefore, we surveyed the influence of the flood pulse on fish communities that inhabit two canals that connect floodplain lakes to the Middle Solimões River. Particularly, we evaluated the hypothesis that the Solimões River flow direction is not perfectly parallel to its banks, which creates peripheral flows that direct water from the rivers to the floodplain lake canals. Our analysis indicated that the seasonal pattern is stronger than the spatial. Beside this, we observed that the positions of the canals in relation to the main river flow somehow affect the fish assemblages. Finally, we conclude that the flood pulse is the main structuring force acting on these fish communities.

  7. HISTORICAL FLOOD RISK MANAGEMENT: SPATIAL EXPANSION OF GHERGHIȚA VILLAGE (LOWER PRAHOVA RIVER

    Directory of Open Access Journals (Sweden)

    IOANA-TOROIMAC GABRIELA

    2015-03-01

    Full Text Available This paper analyses settlements expansion in flood zones during historical time. We focused on the example of Gherghiţa village on Lower Prahova River by using a diachronic study in GIS. It revealed three major periods of extension of Gherghița village and flood risk management: (1 from Middle Age to the end of the 19th century – prevention against floods by expansion outside the flood-prone area; (2 during the major part of the 20th – flood negligence by expansion inside the flood-prone area; (3 at the end of the 20th century and at the beginning of the 21th century – protection against floods by extension inside the flood-prone area with structural measures (i.e. levees. As a consequence, human pressure on Lower Prahova River grew since the beginning of the 20th century, especially for agricultural purposes.

  8. Real-time flood forecast and flood alert map over the Huaihe River Basin in China using a coupled hydro-meteorological modeling system

    Institute of Scientific and Technical Information of China (English)

    LIN; Charles; A.

    2008-01-01

    A coupled hydro-meteorological modeling system is established for real-time flood forecast and flood alert over the Huaihe River Basin in China. The system consists of the mesoscale atmospheric model MC2 (Canadian Mesoscale Compressible Community) that is one-way coupled to the Chinese Xinanjiang distributed hydrological model, a grid-based flow routing model, and a module for acquiring real-time gauge precipitation. The system had been successfully tested in a hindcast mode using 1998 and 2003 flood cases in the basin, and has been running daily in a real-time mode for the summers of 2005 and 2006 over the Wangjiaba sub-basin of the Huaihe River Basin. The MC2 precipitation combined with gauge values is used to drive the Xinanjiang model for hydrograph prediction and production of flood alert map. The performance of the system is illustrated through an examination of real-time flood forecasts for the severe flood case of July 4―15, 2005 over the sub-basin, which was the first and largest flood event encountered to date. The 96-h forecasts of MC2 precipitation are first evaluated using observations from 41 rain gauges over the sub-basin. The forecast hydrograph is then validated with observations at the Wangjiaba outlet of the sub-basin. MC2 precipitation generally compares well with gauge values. The flood peak was predicted well in both timing and intensity in the 96-hour forecast using the combined gauge-MC2 precipitation. The real-time flood alert map can spatially display the propagation of forecast floods over the sub-basin. Our forecast hydrograph was used as opera-tional guidance by the Bureau of Hydrograph, Ministry of Water Resources. Such guidance has been proven very useful for the Office of State Flood Control and Drought Relief Headquarters in operational decision making for flood management. The encouraging results demonstrate the potential of using mesoscale atmospheric model precipitation for real-time flood forecast, which can result in a longer

  9. A multidating approach applied to historical slackwater flood deposits of the Gardon River, SE France

    Science.gov (United States)

    Dezileau, L.; Terrier, B.; Berger, J. F.; Blanchemanche, P.; Latapie, A.; Freydier, R.; Bremond, L.; Paquier, A.; Lang, M.; Delgado, J. L.

    2014-06-01

    A multidating approach was carried out on slackwater flood deposits, preserved in valley side rock cave and terrace, of the Gardon River in Languedoc, southeast France. Lead-210, caesium-137, and geochemical analysis of mining-contaminated slackwater flood sediments have been used to reconstruct the history of these flood deposits. These age controls were combined with the continuous record of Gardon flow since 1890, and the combined records were then used to assign ages to slackwater deposits. The stratigraphic records of terrace GE and cave GG were excellent examples to illustrate the effects of erosion/preservation in a context of a progressively self-censoring, vertically accreting sequence. The sedimentary flood record of the terrace GE located at 10 m above the channel bed is complete for years post-1958 but incomplete before. During the 78-year period 1880-1958, 25 floods of a sufficient magnitude (> 1450 m3/s) have covered the terrace. Since 1958, however, the frequency of inundation of the deposits has been lower: only 5 or 6 floods in 52 years have been large enough to exceed the necessary threshold discharge (> 1700 m3/s). The progressive increase of the threshold discharge and the reduced frequency of inundation at the terrace could allow stabilization of the vegetation cover and improve protection against erosion from subsequent large magnitude flood events. The sedimentary flood record seems complete for cave GG located at 15 m above the channel bed. Here, the low frequency of events would have enabled a high degree of stabilization of the sedimentary flood record, rendering the deposits less susceptible to erosion. Radiocarbon dating is used in this study and compared to the other dating techniques. Eighty percent of radiocarbon dates on charcoals were considerably older than those obtained by the other techniques in the terrace. On the other hand, radiocarbon dating on seeds provided better results. This discrepancy between radiocarbon dates on

  10. RESEARCH ON SYSTEM OF FLOOD DISASTER CONTROL AND REDUCTION SUPPORTED BY GIS IN MEDIUM AND SMALL BASINS

    Institute of Scientific and Technical Information of China (English)

    XUYon-peng; DUJin-kang; 等

    2002-01-01

    Southeast China coastal areas belong to subtropical monsoon climatic zone,thus easily affected by floods resulted from typhoons and rainstorm.Since the areas of river basins are small,rivers flood regulation capacities are low,and therefore flood hazard is grave.In the paper,taking the Yongjiang basin in southeast China as an example,the approaches and methods of geographic information system(GIS) applied to flood disaster control and reduction research on small basin are explred.On GIS help the rainfall-runoff calculation model and the river dchannel flood routing model are developed.And the evaluating flood submerged are and the damage assessment models are built supported by digit elevation models.Lastly the decision support system on GIS supported for flood control in research basin has been set up.This greatly improves flood-proofing decision-making capacities in river basin,and provides valuable information and a mode for flood prevention and reduction in the medium and small basin .Meanwhile,the research indicates that technologies of GIS provide a powerful tool for flood disaster control.

  11. Impact of wet season river flood discharge on phytoplankton absorption properties in the southern Great Barrier Reef region coastal waters

    Science.gov (United States)

    Cherukuru, Nagur; Brando, Vittorio E.; Blondeau-Patissier, David; Ford, Phillip W.; Clementson, Lesley A.; Robson, Barbara J.

    2017-09-01

    Light absorption due to particulate and dissolved material plays an important role in controlling the underwater light environment and the above water reflectance signature. Thorough understanding of absorption properties and their variability is important to estimate light propagation in the water column. However, knowledge of light absorption properties in flood impacted coastal waters is limited. To address this knowledge gap we investigated a bio-optical dataset collected during a flood (2008) in the southern Great Barrier Reef (GBR) region coastal waters. Results presented here show strong impact of river flood discharges on water column stratification, distribution of suspended substances and light absorption properties in the study area. Bio-optical analysis showed phytoplankton absorption efficiency to reduce in response to increased coloured dissolved organic matter presence in flood impacted coastal waters. Biogeophysical property ranges, relationships and parametrisation presented here will help model realistic underwater light environment and optical signature in flood impacted coastal waters.

  12. Appendix E: Research papers. Manual versus digital LANDSAT analysis for modeling river flooding. [Black River, New York

    Science.gov (United States)

    Philipson, W. R. (Principal Investigator); Hafker, W. R.

    1980-01-01

    The comparative value of manual versus digital image analysis for determining flood boundaries is being examined in a study of the use of LANDSAT data for modeling flooding of the Black River, in northern New York. The work is an extension of an earlier study in which Black River flooding was assessed through visually interpreted, multi-date LANDSAT band 7 images. Based on the results to date, it appears that neither color-additive viewing nor digital analysis of LANDSAT data provide improvement in accuracy over visual analysis of band 7 images, for delineating the boundaries of flood-affected areas.

  13. Vistula River bed erosion processes and their influence on Warsaw’s flood safety

    OpenAIRE

    Magnuszewski, A.; Moran, S

    2015-01-01

    Large cities have historically been well protected against floods as a function of their importance to society. In Warsaw, Poland, located on a narrow passage of the Vistula River valley, urban flood disasters were not unusual. Beginning at the end of the 19th century, the construction of river embankment and training works caused the narrowing of the flood passage path in the downtown reach of the river. The process of bed erosion lowered the elevation of the river bed by 205 cm over the 20t...

  14. Vistula River bed erosion processes and their influence on Warsaw's flood safety

    Science.gov (United States)

    Magnuszewski, A.; Moran, S.

    2015-03-01

    Large cities have historically been well protected against floods as a function of their importance to society. In Warsaw, Poland, located on a narrow passage of the Vistula River valley, urban flood disasters were not unusual. Beginning at the end of the 19th century, the construction of river embankment and training works caused the narrowing of the flood passage path in the downtown reach of the river. The process of bed erosion lowered the elevation of the river bed by 205 cm over the 20th century, and the consequences of bed lowering are reflected by the rating curve change. Conditions of the flood passage have been analysed by the CCHE2D hydrodynamic model both in retro-modelling and scenario simulation modelling. The high water mark of the 1844 flood and iterative calculations in retro-modelling made possible estimation of the discharge, Q = 8250 m3 s-1. This highest observed historical flood in a natural river has been compared to recent conditions of the Vistula River in Warsaw by scenario modelling. The result shows dramatic changes in water surface elevation, velocities, and shear stress. The vertical velocity in the proximity of Port Praski gauge at km 513 can reach 3.5 m s-1, a very high value for a lowland river. The average flow conveyance is improving due to channel erosion but also declining in the case of extreme floods due to high resistance from vegetation on the flood plains.

  15. Vistula River bed erosion processes and their influence on Warsaw’s flood safety

    Directory of Open Access Journals (Sweden)

    A. Magnuszewski

    2015-03-01

    Full Text Available Large cities have historically been well protected against floods as a function of their importance to society. In Warsaw, Poland, located on a narrow passage of the Vistula River valley, urban flood disasters were not unusual. Beginning at the end of the 19th century, the construction of river embankment and training works caused the narrowing of the flood passage path in the downtown reach of the river. The process of bed erosion lowered the elevation of the river bed by 205 cm over the 20th century, and the consequences of bed lowering are reflected by the rating curve change. Conditions of the flood passage have been analysed by the CCHE2D hydrodynamic model both in retro-modelling and scenario simulation modelling. The high water mark of the 1844 flood and iterative calculations in retro-modelling made possible estimation of the discharge, Q = 8250 m3 s−1. This highest observed historical flood in a natural river has been compared to recent conditions of the Vistula River in Warsaw by scenario modelling. The result shows dramatic changes in water surface elevation, velocities, and shear stress. The vertical velocity in the proximity of Port Praski gauge at km 513 can reach 3.5 m s−1, a very high value for a lowland river. The average flow conveyance is improving due to channel erosion but also declining in the case of extreme floods due to high resistance from vegetation on the flood plains.

  16. Improving riparian wetland conditions based on infiltration and drainage behavior during and after controlled flooding

    Science.gov (United States)

    Russo, Tess A.; Fisher, Andrew T.; Roche, James W.

    2012-04-01

    SummaryWe present results of an observational and modeling study of the hydrologic response of a riparian wetland to controlled flooding. The study site is located in Poopenaut Valley, Yosemite National Park (USA), adjacent to the Tuolumne River. This area is flooded periodically by releases from the Hetch Hetchy Reservoir, and was monitored during one flood sequence to assess the relative importance of inundation versus groundwater rise in establishing and maintaining riparian wetland conditions, defined on the basis of a minimum depth and duration of soil saturation, and to determine how restoration benefits might be achieved while reducing total flood discharge. Soil moisture data show how shallow soils were wetted by both inundation and a rising water table as the river hydrograph rose repeatedly during the controlled flood. The shallow groundwater aquifer under wetland areas responded quickly to conditions in the adjacent river, demonstrating a good connection between surface and subsurface regimes. The observed soil drainage response helped to calibrate a numerical model that was used to test scenarios for controlled flood releases. Modeling of this groundwater-wetland system suggests that inundation of surface soils is the most effective mechanism for developing wetland conditions, although an elevated water table helps to extend the duration of soil saturation. Achievement of wetland conditions can be achieved with a smaller total flood release, provided that repeated cycling of higher and lower river elevations is timed to benefit from the characteristic drainage behavior of wetland soils. These results are robust to modest variations in the initial water table elevation, as might result from wetter or dryer conditions prior to a flood. However, larger changes to initial water table elevation, as could be associated with long term climate change or drought conditions, would have a significant influence on wetland development. An ongoing controlled flooding

  17. Reconstructing the Tropical Storm Ketsana flood event in Marikina River, Philippines

    Directory of Open Access Journals (Sweden)

    C. C. Abon

    2011-04-01

    Full Text Available In September 2009, Tropical Storm Ketsana (local name: TS Ondoy hit the Manila metropolitan area (Metro Manila and brought an anomalous volume of rain that exceeded the Philippines' forty-year meteorological record. The storm caused exceptionally high and extensive flooding. Part of this study was a survey conducted along the stretch of the Marikina River, one of the major rivers that flooded. Post-event resident interviews were used to reconstruct the flooding in the absence of stream gauge data. Hydraulic and hydrologic modeling were carried out to understand the mechanism that brought the flood. Peak floods occurred at different hours along the river resulting from the transmission of water from the main watershed to the downstream areas. Modeled peak flood and flood timing coincided well with actual observations except for downstream stations where actual peak floods were observed to have occurred at a later time. Compounding factors such as other flood sources and stream backflow could have caused this discrepancy. Nevertheless, prediction of flood heights and the use of the known time lag between the peak rainfall and the peak runoff could be utilized to issue timely flood forecasts to allow people to prepare for future flooding.

  18. A Review of Flood-Related Storage and Remobilization of Heavy Metal Pollutants in River Systems.

    Science.gov (United States)

    Ciszewski, Dariusz; Grygar, Tomáš Matys

    Recently observed rapid climate changes have focused the attention of researchers and river managers on the possible effects of increased flooding frequency on the mobilization and redistribution of historical pollutants within some river systems. This text summarizes regularities in the flood-related transport, channel-to-floodplain transfer, and storage and remobilization of heavy metals, which are the most persistent environmental pollutants in river systems. Metal-dispersal processes are essentially much more variable in alluvia than in soils of non-inundated areas due to the effects of flood-sediment sorting and the mixing of pollutants with grains of different origins in a catchment, resulting in changes of one to two orders of magnitude in metal content over distances of centimetres. Furthermore, metal remobilization can be more intensive in alluvia than in soils as a result of bank erosion, prolonged floodplain inundation associated with reducing conditions alternating with oxygen-driven processes of dry periods and frequent water-table fluctuations, which affect the distribution of metals at low-lying strata. Moreover, metal storage and remobilization are controlled by river channelization, but their influence depends on the period and extent of the engineering works. Generally, artificial structures such as groynes, dams or cut-off channels performed before pollution periods favour the entrapment of polluted sediments, whereas the floodplains of lined river channels that adjust to new, post-channelization hydraulic conditions become a permanent sink for fine polluted sediments, which accumulate solely during overbank flows. Metal mobilization in such floodplains takes place only by slow leaching, and their sediments, which accrete at a moderate rate, are the best archives of the catchment pollution with heavy metals.

  19. Flood-inundation map library for the Licking River and South Fork Licking River near Falmouth, Kentucky

    Science.gov (United States)

    Lant, Jeremiah G.

    2016-09-19

    Digital flood inundation maps for a 17-mile reach of Licking River and 4-mile reach of South Fork Licking River near Falmouth, Kentucky, were created by the U.S. Geological Survey (USGS) in cooperation with Pendleton County and the U.S. Army Corps of Engineers–Louisville District. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science 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 Licking River at Catawba, Ky., (station 03253500) and the USGS streamgage on the South Fork Licking River at Hayes, Ky., (station 03253000). Current conditions (2015) for the USGS streamgages may be obtained online at the USGS National Water Information System site (http://waterdata.usgs.gov/nwis). In addition, the streamgage information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system (http:/water.weather.gov/ahps/). The flood hydrograph forecasts provided by the NWS are usually collocated with USGS streamgages. The forecasted peak-stage information, also available on the NWS Web site, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation.In this study, flood profiles were computed for the Licking River reach and South Fork Licking River reach by using a one-dimensional step-backwater model. The hydraulic model was calibrated by using the most current (2015) stage-discharge relations for the Licking River at Catawba, Ky., and the South Fork Licking River at Hayes, Ky., USGS streamgages. The calibrated model was then used to calculate 60 water-surface profiles for a sequence of flood stages, at 2-foot intervals, referenced to the streamgage datum and ranging from an elevation near bankfull to the elevation associated with a major flood that

  20. Novel plant communities limit the effects of a managed flood to restore riparian forests along a large regulated river

    Science.gov (United States)

    Cooper, D.J.; Andersen, D.C.

    2012-01-01

    Dam releases used to create downstream flows that mimic historic floods in timing, peak magnitude and recession rate are touted as key tools for restoring riparian vegetation on large regulated rivers. We analysed a flood on the 5th-order Green River below Flaming Gorge Dam, Colorado, in a broad alluvial valley where Fremont cottonwood riparian forests have senesced and little recruitment has occurred since dam completion in 1962. The stable post dam flow regime triggered the development of novel riparian communities with dense herbaceous plant cover. We monitored cottonwood recruitment on landforms inundated by a managed flood equal in magnitude and timing to the average pre-dam flood. To understand the potential for using managed floods as a riparian restoration tool, we implemented a controlled and replicated experiment to test the effects of artificially modified ground layer vegetation on cottonwood seedling establishment. Treatments to remove herbaceous vegetation and create bare ground included herbicide application (H), ploughing (P), and herbicide plus ploughing (H+P). Treatment improved seedling establishment. Initial seedling densities on treated areas were as much as 1200% higher than on neighbouring control (C) areas, but varied over three orders of magnitude among the five locations where manipulations were replicated. Only two replicates showed the expected seedling density rank of (H+P)>P>H>C. Few seedlings established in control plots and none survived 1 year. Seedling density was strongly affected by seed rain density. Herbivory affected growth and survivorship of recruits, and few survived nine growing seasons. Our results suggest that the novel plant communities are ecologically and geomorphically resistant to change. Managed flooding alone, using flows equal to the pre-dam mean annual peak flood, is an ineffective riparian restoration tool where such ecosystem states are present and floods cannot create new habitat for seedling establishment

  1. A Framework for Flood Risk Analysis and Benefit Assessment of Flood Control Measures in Urban Areas

    OpenAIRE

    Li, Chaochao; Cheng, Xiaotao; Li, Na; Du, Xiaohe; Yu, Qian; Kan, Guangyuan

    2016-01-01

    Flood risk analysis is more complex in urban areas than that in rural areas because of their closely packed buildings, different kinds of land uses, and large number of flood control works and drainage systems. The purpose of this paper is to propose a practical framework for flood risk analysis and benefit assessment of flood control measures in urban areas. Based on the concept of disaster risk triangle (hazard, vulnerability and exposure), a comprehensive analysis method and a general proc...

  2. Rossitsa River Basin: Flood Hazard and Risk Identification

    Science.gov (United States)

    Mavrova-Guirguinova, Maria; Pencheva, Denislava

    2017-04-01

    The process of Flood Risk Management Planning and adaptation of measures for flood risk reduction as the Early Warning provoke the necessity of surveys involving Identification aspects. This project presents risk identification combining two lines of analysis: (1) Creation a mathematical model of rainfall-runoff processes in a watershed based on limited number of observed input and output variables; (2) Procedures for determination of critical thresholds - discharges/water levels corresponding to certain consequences. The pilot region is Rossitsa river basin, Sevlievo, Bulgaria. The first line of analysis follows next steps: (a) Creation and calibration of Unit Hydrograph Models based on limited number of observed data for discharge and precipitation; The survey at the selected region has 22 observations for excess rainfall and discharge. (b) The relations of UHM coefficients from the input parameters have been determined statistically, excluding the ANN model of the run-off coefficient as a function of 3 parameters (amount of precipitation two days before, soil condition, intensity of the rainfall) where a feedforward neural network is used. (c) Additional simulations with UHM aiming at generation of synthetic data for rainfall-runoff events, which extend the range of observed data; (d) Training, validation and testing a generalized regional ANN Model for discharge forecasting with 4 input parameters, where the training data set consists of synthetic data, validation and testing data sets consists of observations. A function between consequences and discharges has been reached in the second line of analysis concerning critical hazard levels determination. Unsteady simulations with the hydraulic model using three typical hydrographs for determination of the existing time for reaction from one to upper critical threshold are made. Correction of the critical thresholds aiming at providing necessary time for reaction between the thresholds and probability analysis of

  3. Regional Flood Frequency Analysis in the Volta River Basin, West Africa

    Directory of Open Access Journals (Sweden)

    Kossi Komi

    2016-02-01

    Full Text Available In the Volta River Basin, flooding has been one of the most damaging natural hazards during the last few decades. Therefore, flood frequency estimates are important for disaster risk management. This study aims at improving knowledge of flood frequencies in the Volta River Basin using regional frequency analysis based on L-moments. Hence, three homogeneous groups have been identified based on cluster analysis and a homogeneity test. By using L-moment diagrams and goodness of fit tests, the generalized extreme value and the generalized Pareto distributions are found suitable to yield accurate flood quantiles in the Volta River Basin. Finally, regression models of the mean annual flood with the size of the drainage area, mean basin slope and mean annual rainfall are proposed to enable flood frequency estimation of ungauged sites within the study area.

  4. Modeling Flood & Drought Scenario for Water Management in Porali River Basin, Balochistan

    Directory of Open Access Journals (Sweden)

    Shoaib Ahmed

    2013-12-01

    Full Text Available Recent history shows that floods have become a frequently occurring disaster in Balochistan, especially during monsoon season. Two rivers, river Porali and river Kud overflows, inundating its banks and causing destruction to cultivated land and property. This study is an attempt to identify flood prone areas of Porali river basin for future flood scenario and propose possible reservoir locations for excess flood water storage. Computer-based models Hydrological Simulation Program-FORTRAN (HSPF and HEC-river analysis system (HEC-RAS are used as tools to simulate existing and future flood and drought scenarios. Models are calibrated and validated using data from 3 weather stations, namely Wadh, Bela, and Uthal and stream flow data from two gauging stations. The highest and the lowest 10 years of precipitation data are extracted, from historic dataset of all stations, to attain future flooding and drought scenarios, respectively. Flood inundation map is generated highlighting agricultural prone land and settlements of the watershed. Using Digital Elevation Model (DEM and volume of water calculated from the flood scenario, possible locations for reservoirs are marked that can store excess water for the use in drought years. Flow and volume of water has also been simulated for drought scenario. Analyses show that 3 × 109 m3 of water available due to immense flooding that is sufficient for the survival for one drought year, as the volume of water for latter scenario is 2.9 × 108m3.

  5. Incorporating river morphological changes to flood risk assessment: uncertainties, methodology and application

    Directory of Open Access Journals (Sweden)

    C. Neuhold

    2009-05-01

    Full Text Available Risk zonation maps are mostly derived from design floods which propagate through the study area. The respective delineation of inundated flood plains is a fundamental input for the flood risk assessment of exposed objects. It is implicitly assumed that the river morphology will not vary, even though it is obvious that the river bed elevation can quickly and drastically change during flood events. The objectives of this study were to integrate the river bed dynamics into the flood risk assessment procedure and to quantify associated uncertainties. The proposed concept was applied to the River Ill in the Western Austrian Alps. In total, 138 flood and associated sediment transport scenarios were considered, simulated and illustrated for the main river stem. The calculated morphological changes of the river bed at the moment of peak flow provided a basis to estimate the variability of possible water surface levels and inundation lines which should be incorporated into flood hazard assessment. In the context of vulnerability assessment an advanced methodological approach to assess flood risk based on damage probability functions is described.

  6. Mathematical model for flood routing in Jingjiang River and Dongting Lake network

    Directory of Open Access Journals (Sweden)

    Zuo-tao XIE

    2012-09-01

    Full Text Available The main stream of the Yangtze River, Dongting Lake, and the river network in the Jingjiang reach of the Yangtze River constitute a complex water system. This paper develops a one-dimensional (1-D mathematical model for flood routing in the river network of the Jingjiang River and Dongting Lake using the explicit finite volume method. Based on observed data during the flood periods in 1996 and 1998, the model was calibrated and validated, and the results show that the model is effective and has high accuracy. In addition, the one-dimensional mathematical model for the river network and the horizontal two-dimensional (2-D mathematical model for the Jingjiang flood diversion area were coupled to simulate the flood process in the Jingjiang River, Dongting Lake, and the Jingjiang flood diversion area. The calculated results of the coupled model are consistent with the practical processes. Meanwhile, the results show that the flood diversion has significant effects on the decrease of the peak water level at the Shashi and Chenjiawan hydrological stations near the flood diversion gates, and the effect is more obvious in the downstream than in the upstream.

  7. RESEARCH ON SYSTEM OF FLOOD DISASTER CONTROL AND REDUCTION SUPPORTED BY GIS IN MEDIUM AND SMALL BASINS

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Southeast China coastal areas belong to subtropical monsoon climatic zone, thus easily affected by floodsresulted from typhoons and rainstorms. Since the areas of river basins are smnall, rivers flood regulation capacities arelow, and therefore flood hazard is grave. In this paper, taking the Yongjiang basin in southeast China as an example, theapproaches and methods of geographic information system(GIS) applied to flood disaster control and reduction researchon small basin are explored. On GIS help the rainfall-runoff calculation model and the river channel flood routing modelare developed. And the evaluating flood submerged area and the damage assessment models are built supported by digitelevation models. Lastly the decision support system on GIS supported for flood control in research basin has been set up.This greatly improves flood-proofing decision-making capacities in river basin, and provides valuable information and amode for flood prevention and reduction in the medium and small basin. Meanwhile, the research indicates that technolo-gies of GIS provide a powerful tool for flood disaster control.

  8. Optimized cascade reservoir operation considering ice flood control and power generation

    Science.gov (United States)

    Chang, Jianxia; Meng, Xuejiao; Wang, ZongZhi; Wang, Xuebin; Huang, Qiang

    2014-11-01

    Ice flood control is an important objective for reservoir operation in cold regions. Maintaining the reservoir outflow in a certain range is considered an effective way to remediate ice flood damage. However, this strategy may decrease the socio-economic benefit of reservoirs, for example, reduction of hydropower production. These conflicting objectives cause a dilemma for water managers when defining reservoir operation policy. This study considers seven cascade reservoirs in the upstream Yellow River, and ice flood control storage is introduced to balance the hydropower generation and ice flood control. The relation between the ice flood control storage volume of the Liujiaxia reservoir and cascade power output is analyzed. An optimization model to explore the trade-offs between hydropower generation and ice flood control requirements is developed. The model takes into account ice flood control requirements. The optimization model compared to simulation model based on the reservoir operation rule curves. The results show that the optimal operation rules are far more efficient in balancing the benefits within the power generation and ice flood control. The cascade reservoirs operation strategies proposed in this study can be effectively and suitably used in reservoir operation systems with similar conditions.

  9. 33 CFR 209.220 - Flood control regulations.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Flood control regulations. 209..., DEPARTMENT OF DEFENSE ADMINISTRATIVE PROCEDURE § 209.220 Flood control regulations. (a) Local protection... probable date of transfer. (b) Use of storage allocated for flood control or navigation at...

  10. 33 CFR 209.300 - Flood control regulations.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Flood control regulations. 209..., DEPARTMENT OF DEFENSE ADMINISTRATIVE PROCEDURE § 209.300 Flood control regulations. (a) Regulations for the... authority contained in Section 3 of the Flood Control Act of June 22, 1936, as amended and supplemented,...

  11. The impacts of '05.6' extreme flood event on riverine carbon fluxes in Xijiang River

    Institute of Scientific and Technical Information of China (English)

    SUN HuiGuo; HAN JingTai; ZHANG ShuRong; LU XiXi

    2007-01-01

    An extreme flood event with a frequency of nearly 200 year occurred in June of 2005 in the Xijiang River,the main trunk stream of the Zhujiang River. Samples were systematically collected during the flood event, and water quality parameters, including total suspended sediment (TSS), dissolved inorganic carbon (DIC), dissolved organic carbon (DOC), and particulate organic carbon (POC) were analyzed,and riverine carbon concentrations associated with its changing pattern through the flood process were discussed. These parameters reflect the changes in basin surface flow and subsurface flow during the flood. This flood event influenced annual flux estimations of POC, DOC, and DIC to great extents.Based on carbon flux estimations for the year 2005 and the flood event (June 21-28) in the Xijiang River, it was found that DIC, DOC, and POC fluxes during '05.6' flood event are 1.52x106 g.km-2.a-1,0.24x106 g.km-2.a-1, and 0.54x106 g.km-2.a-1, and account for 14.87%, 24.75% and 44.89% of the annual fluxes in 2005, respectively. The results suggested that carbon exports during extreme flood events had great contributions to the total carbon fluxes and composition of various carbon components, being important for accurate estimates of annual carbon fluxes in rivers with frequent floods.

  12. Reconstructing the tropical storm Ketsana flood event in Marikina River, Philippines

    Directory of Open Access Journals (Sweden)

    C. C. Abon

    2010-08-01

    Full Text Available In September 2009, tropical storm Ketsana (local name: TS Ondoy hit Metro Manila and brought an anomalous volume of rain that exceeded the Philippines' forty-year meteorological record. The storm caused exceptionally high and extensive flooding. Part of this study was a survey conducted along the stretch of the Marikina River, one of the major rivers that flooded. Hydraulic and hydrologic modeling was carried out to understand the mechanism that brought the flood. The study revealed that while there were anthropogenic factors that exacerbated flooding in Marikina, the observed flood heights can be simulated in the models generated. Peak floods occurred at different hours along the river resulting from the transmission of water from the main watershed to the downstream areas and the contribution of smaller tributaries entering the main river. Prediction of flood heights and the use of the known time lag between the peak rainfall and the peak runoff could be utilized to issue timely flood forecasts to allow people to prepare for future flooding.

  13. Developing an Intelligent Reservoir Flood Control Decision Support System through Integrating Artificial Neural Networks

    Science.gov (United States)

    Chang, L. C.; Kao, I. F.; Tsai, F. H.; Hsu, H. C.; Yang, S. N.; Shen, H. Y.; Chang, F. J.

    2015-12-01

    Typhoons and storms hit Taiwan several times every year and cause serious flood disasters. Because the mountainous terrain and steep landform rapidly accelerate the speed of flood flow, rivers cannot be a stable source of water supply. Reservoirs become one of the most important and effective floodwater storage facilities. However, real-time operation for reservoir flood control is a continuous and instant decision-making process based on rules, laws, meteorological nowcast, in addition to the immediate rainfall and hydrological data. The achievement of reservoir flood control can effectively mitigate flood disasters and store floodwaters for future uses. In this study, we construct an intelligent decision support system for reservoir flood control through integrating different types of neural networks and the above information to solve this problem. This intelligent reservoir flood control decision support system includes three parts: typhoon track classification, flood forecast and adaptive water release models. This study used the self-organizing map (SOM) for typhoon track clustering, nonlinear autoregressive with exogenous inputs (NARX) for multi-step-ahead reservoir inflow prediction, and adaptive neuro-fuzzy inference system (ANFIS) for reservoir flood control. Before typhoons landfall, we can estimate the entire flood hydrogragh of reservoir inflow by using SOM and make a pre-release strategy and real-time reservoir flood operating by using ANFIS. In the meanwhile, NARX can be constantly used real-time five-hour-ahead inflow prediction for providing the newest flood information. The system has been successfully implemented Typhoons Trami (2013), Fitow (2013) and Matmo (2014) in Shihmen Reservoir.

  14. Rapid Exposure Assessment of Nationwide River Flood for Disaster Risk Reduction

    Science.gov (United States)

    Kwak, Y.; Park, J.; Arifuzzaman, B.; Iwami, Y.; Amirul, Md.; Kondoh, A.

    2016-06-01

    considerably increased. For flood disaster risk reduction, it is important to identify and characterize flood area, locations (particularly lowland along rivers), and durations. For this purpose, flood mapping and monitoring are an imperative process and the fundamental part of risk management as well as emergency response. Our ultimate goal is to detect flood inundation areas over a nationwide scale despite limitations of optical and multispectral images, and to estimate flood risk in terms of affected people. We propose a methodological possibility to be used as a standard approach for nationwide rapid flood exposure assessment with the use of the multi-temporal Moderate Resolution Imaging Spectrometer (MODIS), a big contributor to progress in near-real-time flood mapping. The preliminary results in Bangladesh show that a propensity of flood risk change strongly depends on the temporal and spatial dynamics of exposure such as distributed population.

  15. Flood duration and chute cutoff formation in a wandering gravel-bed river

    Science.gov (United States)

    Sawyer, A.; Wilcox, A. C.

    2015-12-01

    Chute cutoffs occur when a bypass or "chute" channel incises across a bar or low floodplain area, re-distributing water and sediment. Cutoffs result from a setup and a triggering event, typically during overbank flow, but the combined effect of magnitude and duration on potential erosion in in-channel and overbank areas is still poorly constrained. Here we investigated how overbank flow duration impacts cutoff formation and spatiotemporal shear stress patterns in a wandering gravel-bed river. We applied a two-dimensional hydraulic model to a recently reconstructed reach of the Clark Fork River in western Montana that experienced chute cutoffs during a long-duration flood in 2011. Hydrographs with increasing durations exceeding overbank were simulated; for each magnitude-duration combination, various metrics were quantified for in-channel and overbank areas separately. We confirm the hypothesized importance of floodplain elevation, vegetation presence, chute-channel inlet entrance location, and high overbank shear stress zones at bend apexes on cutoff occurrence. Floodplain width plays an important role in controlling unit discharge such that overbank areas are more competent in a narrower floodplain conveyance corridor. Duration controls cumulative flow exceeding sediment mobility thresholds, having the largest effect in overbank areas. Side channels at the reconstructed study site act like naturally formed incipient chutes. This work describes a complex floodplain system characteristic of wandering gravel-bed rivers with implications for understanding morphodynamic evolution, river restoration, and flow management in regulated rivers.

  16. 滦河流域“12.8”洪水特性及其防洪调度探析%Analysis on characteristics of“12.8 Flood” occurred in Luanhe River Basin and its flood control operation

    Institute of Scientific and Technical Information of China (English)

    杨敏; 杨学军

    2013-01-01

    In August 2012,Luanhe River Basin was impacted by both the upper trough with lower-level shear line and the Typhoon" Damrey" ——the lOth typhoon of the year respectively,whereat several strong rainfalls occurred with the precipitations about 20% more than those occurred in the same period of many years.Consequently,severe floods since 1994 happened from several rivers in the basin and then the cities and counties along the rivers were threatened at a certain scale.Through the analysis made herein on the main precipitation processes,the flood features and the characteristics of the relevant flood control operations of the" 12.8 Flood",some references are provided for strengthening the scientific and effective prevention of the flood most likely to occur in Luanhe River Basin.%2012年8月,滦河流域分别受高空槽、低空切变线及10#台风“达维”影响,发生了几场强降水过程,降雨量较多年同期偏多近2成.从而,流域多条河流发生了自1994年以来的大洪水,沿线县(市)受到一定程度洪水威胁.通过对“12.8”洪水主要降雨过程、洪水特性及调度特点分析,为今后加强滦河流域科学有效防御洪水提供参考与借鉴.

  17. Flood profiles of the Alafia River, west-central Florida, computed by step-backwater method

    Science.gov (United States)

    Robertson, A.F.

    1977-01-01

    The Alafia River is a coastal stream that discharges into Hillsborough Bay. The river and its two principal tributaries, North Prong Alafia River and South Prong Alafia River, drain an area of 420 sq mi of predominantly rural land. However, near the coast, urban residential developments are increasing. The flood plain of the river is subject to flooding, particularly during large regional storms. Peak-discharge frequencies have been determined for data available at two gaging stations in the basin. The flood profiles for peak discharges of recurrence intervals of 2.33, 5, 10, 25, 50, 100, and 200 years have been determined using the step-backwater method. These profiles can be used in conjunction with topographic maps to delineate the area of flooding. Flood profiles were not determined for the tidally affected area near the mouth of the river. Flood marks were located that can be associated with the 1960 flood which occurred when Hurricane Donna passed over the area. (Woodard-USGS)

  18. Tool for decision-making regarding general evacuation during a rapid river flood.

    Science.gov (United States)

    Radosavljevic, V; Belojevic, G; Pavlovic, N

    2017-05-01

    To propose a simple and effective tool for decision-making regarding general evacuation during a rapid river flood. Virtual testing of a tool in a real event. A four-component tool was applied to build an alternative scenario of the catastrophic river flood in Obrenovac, Serbia, on May 2014. The components of this tool are: (1) the amount of precipitation above the 95th percentile of all previous measurements; (2) upstream river discharge above the 95th percentile of all previous measurements; (3) upstream river level above the 95th percentile of all previous measurements; and (4) worsening of the hydrometeorological situation in the following 48 h. In the early morning of 16 May 2014, a rapid river wave flooded 80% of the Obrenovac territory. There were 13 deaths due to drowning. Application of the study tool shows that these lives could have been saved, as the score to recommend general evacuation was reached 1 day before the flooding. The application of this tool to two previous great floods in Serbia shows that the score to recommend general evacuation was reached either 1 day before or on the onset of flash flooding. Due to its simplicity, this tool is universally applicable to facilitate decision-making regarding general evacuation during a rapid river flood, and it should be further tested in future similar catastrophes. Copyright © 2017 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

  19. Development of roughness updating based on artificial neural network in a river hydraulic model for flash flood forecasting

    Indian Academy of Sciences (India)

    J C Fu; M H Hsu; Y Duann

    2016-02-01

    Flood is the worst weather-related hazard in Taiwan because of steep terrain and storm. The tropical storm often results in disastrous flash flood. To provide reliable forecast of water stages in rivers is indispensable for proper actions in the emergency response during flood. The river hydraulic model based on dynamic wave theory using an implicit finite-difference method is developed with river roughness updating for flash flood forecast. The artificial neural network (ANN) is employed to update the roughness of rivers in accordance with the observed river stages at each time-step of the flood routing process. Several typhoon events at Tamsui River are utilized to evaluate the accuracy of flood forecasting. The results present the adaptive n-values of roughness for river hydraulic model that can provide a better flow state for subsequent forecasting at significant locations and longitudinal profiles along rivers.

  20. A Cultural Resource Assessment of the Pembilier Lake and Dam Flood Control Project (A Literature and Records Search), Pembina River, Pembina and Cavalier Counties, North Dakota.

    Science.gov (United States)

    1980-11-03

    lived, at least seasonally, around the Red River settlement, near present Winnipeg (Ross 1957, Woolworth 1975). Only during the summer and fall hunts...fish and deer meat ( Woolworth 1975). Ross (1957) provides an excellent account of a combined Metis- Chippewa hunt that took place during the summer of...1840, Joseph Rollette was sent to Pembina by the fur .’:4 trade partners Henry Sibley and Norman Kittson (Lee 1897; Robinson 1966; Woolworth 1975

  1. Formation of fine sediment deposit from a flash flood river in the Mediterranean Sea

    Science.gov (United States)

    Grifoll, Manel; Gracia, Vicenç; Aretxabaleta, Alfredo L.; Guillén, Jorge; Espino, Manuel; Warner, John C.

    2014-01-01

    We identify the mechanisms controlling fine deposits on the inner-shelf in front of the Besòs River, in the northwestern Mediterranean Sea. This river is characterized by a flash flood regime discharging large amounts of water (more than 20 times the mean water discharge) and sediment in very short periods lasting from hours to few days. Numerical model output was compared with bottom sediment observations and used to characterize the multiple spatial and temporal scales involved in offshore sediment deposit formation. A high-resolution (50 m grid size) coupled hydrodynamic-wave-sediment transport model was applied to the initial stages of the sediment dispersal after a storm-related flood event. After the flood, sediment accumulation was predominantly confined to an area near the coastline as a result of preferential deposition during the final stage of the storm. Subsequent reworking occurred due to wave-induced bottom shear stress that resuspended fine materials, with seaward flow exporting them toward the midshelf. Wave characteristics, sediment availability, and shelf circulation determined the transport after the reworking and the final sediment deposition location. One year simulations of the regional area revealed a prevalent southwestward average flow with increased intensity downstream. The circulation pattern was consistent with the observed fine deposit depocenter being shifted southward from the river mouth. At the southern edge, bathymetry controlled the fine deposition by inducing near-bottom flow convergence enhancing bottom shear stress. According to the short-term and long-term analyses, a seasonal pattern in the fine deposit formation is expected.

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

    Science.gov (United States)

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

    2017-04-01

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

  3. Flood-inundation maps for the Yellow River at Plymouth, Indiana

    Science.gov (United States)

    Menke, Chad D.; Bunch, Aubrey R.; Kim, Moon H.

    2016-11-16

    Digital flood-inundation maps for a 4.9-mile reach of the Yellow River at Plymouth, Indiana (Ind.), were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage 05516500, Yellow River at Plymouth, Ind. Current conditions for estimating near-real-time areas of inundation using USGS streamgage information may be obtained on the Internet at http://waterdata.usgs.gov/in/nwis/uv?site_no=05516500. In addition, information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood-warning system (http:/water.weather.gov/ahps/). The NWS AHPS forecasts flood hydrographs at many sites that are often collocated with USGS streamgages, including the Yellow River at Plymouth, Ind. NWS AHPS-forecast peak-stage information may be used in conjunction with the maps developed in this study to show predicted areas of flood and forecasts of flood hydrographs at this site.For this study, flood profiles were computed for the Yellow River reach by means of a one-dimensional step-backwater model. The hydraulic model was calibrated by using the current stage-discharge relations at the Yellow River streamgage, in combination with the flood-insurance study for Marshall County (issued in 2011). The calibrated hydraulic model was then used to determine eight water-surface profiles for flood stages at 1-foot intervals referenced to the streamgage datum and ranging from bankfull to the highest stage of the current stage-discharge rating curve. The 1-percent annual exceedance probability flood profile elevation (flood elevation with recurrence intervals within 100 years) is within

  4. Change in the Magnitude of River Flooding in the United States, 1965-2015

    Data.gov (United States)

    U.S. Environmental Protection Agency — This figure shows changes in the size and frequency of flooding events in rivers and streams in the United States between 1965 and 2015. Blue upward-pointing symbols...

  5. A new look at the Flood Pulse Concept : The (ir)relevance of the moving littoral in temperate zone rivers

    NARCIS (Netherlands)

    Keizer, F. M.; Schot, P. P.; Okruszko, T.; Chormański, J.; Kardel, I.; Wassen, M. J.

    2014-01-01

    The Flood Pulse Concept links the hydraulic river flood pulse to floodplain nutrient status. The edge of inundation, referred to as the moving littoral, causes wetting and drying and input of river derived nutrients, resulting in high floodplain productivity. If during the floods other water sources

  6. Change in the Magnitude of River Flooding in the United States, 1965-2015

    Science.gov (United States)

    This figure shows changes in the size and frequency of flooding events in rivers and streams in the United States between 1965 and 2015. Blue upward-pointing symbols show locations where floods have become larger; brown downward-pointing symbols show locations where floods have become smaller. Data were analyzed by Louise Slater and Gabriele Villarini at the University of Iowa. For more information: www.epa.gov/climatechange/science/indicators

  7. Hydrology, geomorphology, and flood profiles of the Mendenhall River, Juneau, Alaska

    Science.gov (United States)

    Neal, Edward G.; Host, Randy H.

    1999-01-01

    Water-surface-profile elevations for the 2-, 20-, 25-, 50-, and 100-year floods were computed for the Mendenhall River near Juneau, Alaska, using the U.S. Army Corps of Engineers Hydrologic Engineering Center River Analysis System model. The peak discharges for the selected recurrence intervals were determined using the standard log-Pearson type III method. Channel cross sections were surveyed at 60 locations to define hydraulic characteristics over a 5.5-mile reach of river beginning at Mendenhall Lake outlet and extending to the river mouth. A peak flow of 12,400 cubic feet per second occurred on the Mendenhall River on October 20, 1998. This discharge is equivalent to about a 10-year flood on the Mendenhall River and floodmarks produced by this flood were surveyed and used to calibrate the model. The study area is currently experiencing land-surface uplift rates of about 0.05 foot per year. This high rate of uplift has the potential to cause incision or downcutting of the river channel through lowering of the base level. Vertical datum used in the study area was established about 37 years before the most recent surveys of river-channel geometry. The resulting difference between land-surface elevations and sea level continues to increase. Continuing incision of the river channel combined with increased land-surface elevations with respect to sea level may result in computed flood profiles that are higher than actual existing conditions in the tidally influenced reach of the river.

  8. Contrasts of Atmospheric Circulation and Associated Tropical Convection between Huaihe River Valley and Yangtze River Valley Mei-yu Flooding

    Institute of Scientific and Technical Information of China (English)

    HONG Jieli; LIU Yimin

    2012-01-01

    The significant differences of atmospheric circulation between flooding in the Huaihe and Yangtze River valleys during early mei-yu (i.e.,the East Asian rainy season in June) and the related tropical convection were investigated.During the both flooding cases,although the geopotential height anomalies always exhibit equivalent barotropic structures in middle to high latitudes at middle and upper troposphere,the phase of the Rossby wave train is different over Eurasian continent.During flooding in the Huaihe River valley,only one single blocking anticyclone is located over Baikal Lake.In contrast,during flooding in the Yangtze River valley,there are two blocking anticyclones.One is over the Ural Mountains and the other is over Northeast Asia.In the lower troposphere a positive geopotential height anomaly is located at the western ridge of subtropical anticyclone over Western Pacific (SAWP) in both flooding cases,but the location of the height anomaly is much farther north and west during the Huaihe River mei-yu flooding.Furthermore,abnormal rainfall in the Huaihe River valley and the regions north of it in China is closely linked with the latent heating anomaly over the Arabian Sea and Indian peninsula.However,the rainfall in the Yangtze River valley and the regions to its south in China is strongly related to the convection over the western tropical Pacific.Numerical experiments demonstrated that the enhanced latent heating over the Arabian Sea and Indian peninsula causes water vapor convergence in the region south of Tibetan Plateau and in the Huaihe River valley extending to Japan Sea with enhanced precipitation; and vapor divergence over the Yangtze River valley and the regions to its south with deficient precipitation.While the weakened convection in the tropical West Pacific results in moisture converging over the Yangtze River and the region to its south,along with abundant rainfall.

  9. Modelling the socio-economic impact of river floods in Europe

    Science.gov (United States)

    Alfieri, Lorenzo; Feyen, Luc; Salamon, Peter; Thielen, Jutta; Bianchi, Alessandra; Dottori, Francesco; Burek, Peter

    2016-06-01

    River floods generate a large share of the socio-economic impact of weather-driven hazards worldwide. Accurate assessment of their impact is a key priority for governments, international organization, reinsurance companies and emergency responders. Yet, available databases of flood losses over large domains are often affected by gaps and inconsistencies in reported figures. In this work, a framework to reconstruct the economic damage and population affected by river floods at continental scale is applied. Pan-European river flow simulations are coupled with a high-resolution impact assessment framework based on 2-D inundation modelling. Two complementary methods are compared in their ability to estimate the climatological average flood impact and the impact of each flood event in Europe between 1990 and 2013. The event-based method reveals key features, such as the ability to include changes in time of all three components of risk, namely hazard, exposure and vulnerability. Furthermore, it skilfully reproduces the socio-economic impact of major flood events in the past two decades, including the severe flooding hitting central Europe in June 2013. On the other hand, the integral method is capable of reproducing the average flood losses which occurred in Europe between 1998 and 2009. Strengths and limitations of the proposed model are discussed to stress the large potential for filling in the gaps of current datasets of flood impact.

  10. Flood-inundation maps for the Tippecanoe River at Winamac, Indiana

    Science.gov (United States)

    Menke, Chad D.; Bunch, Aubrey R.

    2015-09-25

    Digital flood-inundation maps for a 6.2 mile reach of the Tippecanoe River at Winamac, Indiana (Ind.), were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage 03331753, Tippecanoe River at Winamac, Ind. Current conditions for estimating near-real-time areas of inundation using USGS streamgage information may be obtained on the Internet from the USGS National Water Information System at http://waterdata.usgs.gov/in/nwis/uv?site_no=03331753. In addition, information has been provided by the USGS to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system (http://water.weather.gov/ahps/). The NWS AHPS forecasts flood hydrographs at many sites that are often collocated with USGS streamgages, including the Tippecanoe River at Winamac, Ind. NWS AHPS forecast peak-stage information may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation and forecasts of flood hydrographs at this site.

  11. Analysis and Mapping of Flood Line and Flood Zones within the Godavari River in Nasik Municipal Corporation

    Science.gov (United States)

    Thakre, Deepak

    2010-05-01

    Analysis and Mapping of Flood Line within the Godavari River in Nasik(Municipal Corporation Area) Dr.Deepak N.Thakre Lecturer in Geography L.V.H.College, Nasik-3, Maharashtra, India A flood is an overflow or accumulation of an expanse of water that submerges land when the discharge of a river can not be accommodated within the margins of its normal channel so that water spreads over adjoining area and creates havoc. Problem: Since last few years there has been a sudden increase in rainfall,quite intense during a certain period in monsoon,as a result of which the discharge in river Godavari increases and creates problems in low lying areas on the banks of river Godavari like: submergence of houses,major loss of lives,management failure(due to unexpected dimension of floods)and the disruption of normal life. This paper attempts to analyse and draw an averege flood zone and sudden flood zone on the basis of : 1) Actual field work and survey with the help of Dumpy level and GPS 2) Field interviews of affected people 3) Data available from Meteorological and Irrigation department Among several districts that have flourished in the soils of Indian subcontinent the name of Nashik has drawn the attention of people all over the world. Geographical location of Nashik is 20° 01' to 20° 02' North and 73° 30' to 73° 50'East. Nashik city is situated on the banks of river Godavari and tributaries namely Nasardi, Waghadi, Darna and Walvadi.The total area of Nasik is 264.23 Sq.km (102 Sq.mt) and height from M.S.L is 3284 feet (1001 Mt). River Godavari originates in Western mountain range and flows towards East up to Bay of Bengal. On the upstream of Nasik city dams like Gangapur, Darna, Alandi, Kasyapi and Gautami-Godavari are constructed on river Godavari and its tributaries. Gangapur dam is the nearest storage dam constructed 15km away from Nasik city at source area in the year 1965. Due to moderation of floods and construction of dam there is encroachment in low lying areas

  12. Adige river in Trento flooding map, 1892: private or public risk transfer?

    Science.gov (United States)

    Ranzi, Roberto

    2016-04-01

    For the determination of the flood risk hydrologist and hydraulic engineers focuse their attention mainly to the estimation of physical factors determining the flood hazard, while economists and experts of social sciences deal mainly with the estimation of vulnerability and exposure. The fact that flood zoning involves both hydrological and socio-economic aspects, however, was clear already in the XIX century when the impact of floods on inundated areas started to appear in flood maps, for instance in the UK and in Italy. A pioneering 'flood risk' map for the Adige river in Trento, Italy, was already published in 1892, taking into account in detail both hazard intensity in terms of velocity and depth, frequency of occurrence, vulnerability and economic costs for flood protection with river embankments. This map is likely to be the reinterpreted certainly as a pioneering, and possibly as the first flood risk map for an Italian river and worldwide. Risk levels were divided in three categories and seven sub-categories, depending on flood water depth, velocity, frequency and damage costs. It is interesting to notice the fact that at that time the map was used to share the cost of levees' reparation and enhancement after the severe September 1882 flood as a function of the estimated level of protection of the respective areas against the flood risk. The sharing of costs between public bodies, the railway company and private owners was debated for about 20 years and at the end the public sustained the major costs. This shows how already at that time the economic assessment of structural flood protections was based on objective and rational cost-benefit criteria, that hydraulic risk mapping was perceived by the society as fundamental for the design of flood protection systems and that a balanced cost sharing between public and private was an accepted approach although some protests arose at that time.

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

    NARCIS (Netherlands)

    Kok, de J.L.; Grossmann, M.

    2010-01-01

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

  14. River flood events in Thailand and Bangladesh observed by CryoSat-2

    Science.gov (United States)

    Nielsen, Karina; Villadsen, Heidi; Andersen, Ole; Stenseng, Lars; Knudsen, Per

    2015-04-01

    The high along track resolution of the SIRAL altimeter carried on-board CryoSat-2 offers a wide range of unique opportunities for satellite monitoring. This study focuses on the ability of CryoSat-2 to detect the effects of flood events such as increased river levels and inundation of land. Here we study two flood events; the Bangladesh flood event of June 2012 and the flooding in Thailand that lasted between July 2011 and January 2012. The flooding in these areas was caused by abnormal monsoonal rainfall and affected millions of people. We process CryoSat-2 level 1b SAR mode data to derive water levels for the areas and compare these levels before, during and after the flooding events. Other parameters such as the backscatter coefficient and pulse peakiness are also considered. To verify the extent of the flooding observed by CryoSat-2 we compare with independent sources such as Landsat images.

  15. Flood Hazard Mapping Assessment for El-Awali River Catchment-Lebanon

    Science.gov (United States)

    Hdeib, Rouya; Abdallah, Chadi; Moussa, Roger; Hijazi, Samar

    2016-04-01

    River flooding prediction and flood forecasting has become an essential stage in the major flood mitigation plans worldwide. Delineation of floodplains resulting from a river flooding event requires coupling between a Hydrological rainfall-runoff model to calculate the resulting outflows of the catchment and a hydraulic model to calculate the corresponding water surface profiles along the river main course. In this study several methods were applied to predict the flood discharge of El-Awali River using the available historical data and gauging records and by conducting several site visits. The HEC-HMS Rainfall-Runoff model was built and applied to calculate the flood hydrographs along several outlets on El-Awali River and calibrated using the storm that took place on January 2013 and caused flooding of the major Lebanese rivers and by conducting additional site visits to calculate proper river sections and record witnesses of the locals. The Hydraulic HEC-RAS model was then applied to calculate the corresponding water surface profiles along El-Awali River main reach. Floodplain delineation and Hazard mapping for 10,50 and 100 years return periods was performed using the Watershed Modeling System WMS. The results first show an underestimation of the flood discharge recorded by the operating gauge stations on El-Awali River, whereas, the discharge of the 100 years flood may reach up to 506 m3/s compared by lower values calculated using the traditional discharge estimation methods. Second any flooding of El-Awali River may be catastrophic especially to the coastal part of the catchment and can cause tragic losses in agricultural lands and properties. Last a major floodplain was noticed in Marj Bisri village this floodplain can reach more than 200 meters in width. Overall, performance was good and the Rainfall-Runoff model can provide valuable information about flows especially on ungauged points and can perform a great aid for the floodplain delineation and flood

  16. New version of 1 km global river flood hazard maps for the next generation of Aqueduct Global Flood Analyzer

    Science.gov (United States)

    Sutanudjaja, Edwin; van Beek, Rens; Winsemius, Hessel; Ward, Philip; Bierkens, Marc

    2017-04-01

    The Aqueduct Global Flood Analyzer, launched in 2015, is an open-access and free-of-charge web-based interactive platform which assesses and visualises current and future projections of river flood impacts across the globe. One of the key components in the Analyzer is a set of river flood inundation hazard maps derived from the global hydrological model simulation of PCR-GLOBWB. For the current version of the Analyzer, accessible on http://floods.wri.org/#/, the early generation of PCR-GLOBWB 1.0 was used and simulated at 30 arc-minute ( 50 km at the equator) resolution. In this presentation, we will show the new version of these hazard maps. This new version is based on the latest version of PCR-GLOBWB 2.0 (https://github.com/UU-Hydro/PCR-GLOBWB_model, Sutanudjaja et al., 2016, doi:10.5281/zenodo.60764) simulated at 5 arc-minute ( 10 km at the equator) resolution. The model simulates daily hydrological and water resource fluxes and storages, including the simulation of overbank volume that ends up on the floodplain (if flooding occurs). The simulation was performed for the present day situation (from 1960) and future climate projections (until 2099) using the climate forcing created in the ISI-MIP project. From the simulated flood inundation volume time series, we then extract annual maxima for each cell, and fit these maxima to a Gumbel extreme value distribution. This allows us to derive flood volume maps of any hazard magnitude (ranging from 2-year to 1000-year flood events) and for any time period (e.g. 1960-1999, 2010-2049, 2030-2069, and 2060-2099). The derived flood volumes (at 5 arc-minute resolution) are then spread over the high resolution terrain model using an updated GLOFRIS downscaling module (Winsemius et al., 2013, doi:10.5194/hess-17-1871-2013). The updated version performs a volume spreading sequentially from more upstream basins to downstream basins, hence enabling a better inclusion of smaller streams, and takes into account spreading of water

  17. Historical study of the Rhône river floods (France) and their consequences on the land use evolution

    Science.gov (United States)

    Jouannic, G.; Gargani, J.

    2015-12-01

    This work aims to study the co-evolution of the flooding risk and land use to better understand how, through land use patterns, human societies have adapted to their environment or influenced it. A rereading of the coevolution of floods and society is important to understand both the nature and society and question the issue of land use and human activities in flood areas. River morphology evolution and extreme events occurrence during the last 200 years have been analyzed focusing on the influence of anthropic constructions during the same period of time. We have used these data sets to discuss the co-evolution of nature and societies. The Rhone valley has been significantly constructed (dam, embankment, nuclear power station). These constructions have been built since 1850-1860 in relation with the economic development but also after the decision to better control flooding events which have been taken after the 1856 floods. If the first traces of civilization, especially in the Rhone Valley, show that man has established safe from floods - on the high altitude points, for example - several factors (hydrological period of calm, high population and economic activities growth...) led them to develop their cities and activities in areas submitted to flood risks. If the urbanization of flooding areas has happened and continues to happen, that is mean that some factors have a more decisive influence on the choice of location than the risk presence. Why and when the human has been installed in areas liable to natural hazards? The idea is to identify these factors and prioritize them. In other cases, some major flood could permanently change the human implantation strategies on its territory: according to the impact of floods and the human risk perception, some communities have chosen to leave the risk areas or to change their land uses (agriculture / housing). This study aims to clarify these choices and understand their construction.

  18. Amazon river flow regime and flood recessional agriculture: Flood stage reversals and risk of annual crop loss

    Science.gov (United States)

    Coomes, Oliver T.; Lapointe, Michel; Templeton, Michael; List, Geneva

    2016-08-01

    The annual flood cycle is an important driver of ecosystem structure and function in large tropical rivers such as the Amazon. Riparian peasant communities rely on river fishing and annual floodplain agriculture, closely adapted to the recession phase of the flood pulse. This article reports on a poorly documented but important challenge facing farmers practicing flood recessional agriculture along the Amazon river: frequent, unpredictable stage reversals (repiquetes) which threaten to ruin crops growing on channel bars. We assess the severity of stage reversals for rice production on exposed river mud bars (barreales) near Iquitos, Peru. Crop loss risk is estimated based on a quantitative analysis of 45 years of daily Amazon stage data and field data from floodplain communities nearby in the Muyuy archipelago, upstream of Iquitos. Rice varieties selected, elevations of silt rich bars where rice is sown, as well as planting and harvest dates are analyzed in the light of the timing, frequencies and amplitudes of observed stage reversals that have the potential to destroy growing rice. We find that unpredictable stage reversals can produce substantial crop losses and shorten significantly the length of average growing seasons on lower elevation river bars. The data reveal that local famers extend planting down to lower bar elevations where the mean probabilities of re-submergence before rice maturity (due to reversals) approach 50%, below which they implicitly consider that the risk of crop loss outweighs the potential reward of planting.

  19. FLOOD CHARACTERISTICS AND MANAGEMENT ADAPTATIONS ...

    African Journals Online (AJOL)

    Dr Osondu

    2011-10-26

    , bearing flood losses and land ... Engineering control of the major tributaries of the Imo River system is required to ..... on previous knowledge of physical nature of flood ... uptake; other factors include a lack of formal titles to.

  20. Geomorphic changes resulting from floods in reconfigured gravel-bed river channels in Colorado, USA

    Science.gov (United States)

    Elliott, J.G.; Capesius, J.P.

    2009-01-01

    Geomorphic changes in reconfi gured reaches of three Colorado rivers in response to floods in 2005 provide a benchmark for "restoration" assessment. Sedimententrainment potential is expressed as the ratio of the shear stress from the 2 yr, 5 yr, 10 yr, and 2005 floods to the critical shear stress for sediment. Some observed response was explained by the excess of flood shear stress relative to the resisting force of the sediment. Bed-load entrainment in the Uncompahgre River and the North Fork Gunnison River, during 4 and 6 yr floods respectively, resulted in streambed scour, streambed deposition, lateral-bar accretion, and channel migration at various locations. Some constructed boulder and log structures failed because of high rates of bank erosion or bed-material deposition. The Lake Fork showed little or no net change after the 2005 flood; however, this channel had not conveyed floods greater than the 2.5 yr flood since reconfi guration. Channel slope and the 2 yr flood, a surrogate for bankfull discharge, from all three reconfi gured reaches plotted above the Leopold and Wolman channel-pattern threshold in the "braided channel" region, indicating that braiding, rather than a single-thread meandering channel, and midchannel bar formation may be the natural tendency of these gravel-bed reaches. When plotted against a total stream-power and median-sediment-size threshold for the 2 yr flood, however, the Lake Fork plotted in the "single-thread channel" region, the North Fork Gunnison plotted in the " multiplethread" region, and the Uncompahgre River plotted on the threshold. All three rivers plotted in the multiple-thread region for floods of 5 yr recurrence or greater. ?? 2009 Geological Society of America.

  1. Boundaries - 1997 Red River of the North Flood

    Data.gov (United States)

    Army Corps of Engineers, Department of the Army, Department of Defense — Digital outline of the 1997 flood event. 1997 flooded outline extends from Emerson, Manitoba to Wahpeton, North Dakota. Delineations exist for the entire main stem...

  2. Flood Mitigation of Nyando River Using Duflow Modelling

    Directory of Open Access Journals (Sweden)

    J. Joleha

    2009-01-01

    Full Text Available Duflow surface water hydrodynamic model has been applied using a case study from Nyando catchment in the western part of Kenya in Africa to simulate various extreme flood behaviours and their retardation levels by using selected structural measures as flood mitigation techniques. The objective of this case study was to establish a design flood recommendable for mitigation, and to identify the most cost effective flood mitigation structure. Various design flows are simulated against the different proposed structures hence, the optimal structure can be recommended when economical, social and environmental constraints are considered in the decision making process. The proposed four flood mitigation structures flood plain extension, embankment (dykes, channel by-pass, and green-storage were simulated for 20-year recurrence interval flood to determine their individual responses in storing excess water. The result shows that building a green-storage is the best and optimal structure for flood mitigation.

  3. Legacies of flood reduction on a dryland river

    Science.gov (United States)

    Stromberg, J.C.; Shafroth, P.B.; Hazelton, A.F.

    2012-01-01

    The Bill Williams (Arizona) is a regulated dryland river that is being managed, in part, for biodiversity via flow management. To inform management, we contrasted riparian plant communities between the Bill Williams and an upstream free-flowing tributary (Santa Maria). Goals of a first study (1996-1997) were to identify environmental controls on herbaceous species richness and compare richness among forest types. Analyses revealed that herbaceous species richness was negatively related to woody stem density, basal area and litter cover and positively related to light levels. Introduced Tamarix spp. was more frequent at the Bill Williams, but all three main forest types (Tamarix, Salix/Populus, Prosopis) had low understory richness, as well as high stem density and low light, on the Bill Williams as compared to the Santa Maria. The few edaphic differences between rivers (higher salinity at Bill Williams) had only weak connections with richness. A second study (2006-2007) focused on floristic richness at larger spatial scales. It revealed that during spring, and for the study cumulatively (spring and fall samplings combined), the riparian zone of the unregulated river had considerably more plant species. Annuals (vs. herbaceous perennials and woody species) showed the largest between-river difference. Relative richness of exotic (vs. native) species did not differ. We conclude that: (1) The legacy of reduced scouring frequency and extent at the Bill Williams has reduced the open space available for colonization by annuals; and (2) Change in forest biomass structure, more so than change in forest composition, is the major driver of changes in plant species richness along this flow-altered river. Our study informs dryland river management options by revealing trade-offs that exist between forest biomass structure and plant species richness. ?? 2010 John Wiley & Sons, Ltd.

  4. Flood-inundation maps for the Susquehanna River near Harrisburg, Pennsylvania, 2013

    Science.gov (United States)

    Roland, Mark A.; Underwood, Stacey M.; Thomas, Craig M.; Miller, Jason F.; Pratt, Benjamin A.; Hogan, Laurie G.; Wnek, Patricia A.

    2014-01-01

    A series of 28 digital flood-inundation maps was developed for an approximate 25-mile reach of the Susquehanna River in the vicinity of Harrisburg, Pennsylvania. The study was selected by the U.S. Army Corps of Engineers (USACE) national Silver Jackets program, which supports interagency teams at the state level to coordinate and collaborate on flood-risk management. This study to produce flood-inundation maps was the result of a collaborative effort between the USACE, National Weather Service (NWS), Susquehanna River Basin Commission (SRBC), The Harrisburg Authority, and the U.S. Geological Survey (USGS). These maps are accessible through Web-mapping applications associated with the NWS, SRBC, and USGS. The maps can be used in conjunction with the real-time stage data from the USGS streamgage 01570500, Susquehanna River at Harrisburg, Pa., and NWS flood-stage forecasts to help guide the general public in taking individual safety precautions and will provide local municipal officials with a tool to efficiently manage emergency flood operations and flood mitigation efforts. The maps were developed using the USACE HEC–RAS and HEC–GeoRAS programs to compute water-surface profiles and to delineate estimated flood-inundation areas for selected stream stages. The maps show estimated flood-inundation areas overlaid on high-resolution, georeferenced, aerial photographs of the study area for stream stages at 1-foot intervals between 11 feet and 37 feet (which include NWS flood categories Action, Flood, Moderate, and Major) and the June 24, 1972, peak-of-record flood event at a stage of 33.27 feet at the Susquehanna River at Harrisburg, Pa., streamgage.

  5. Floodplain restoration with flood control: fish habitat value of levee borrow pits

    Science.gov (United States)

    Earthen flood control levees are often built using soil excavated from borrow pits lying parallel to and riverward of the finished levee. After construction, these pits can provide valuable floodplain habitats, and their value is well established along corridors of larger rivers. However, levee bo...

  6. Soil and Sediment Properties Affecting the Transport and Accumulations of Mercury in a Flood Control Reservoir

    Science.gov (United States)

    Mercury accumulations in some fish species from Grenada Lake in north Mississippi exceed the Food and Drug Administration standards for human consumption. This large flood control reservoir serves as a sink for the Skuna and Yalobusha River watersheds whose highly erodible soils contribute to exces...

  7. The politics of flood insecurity : framing contested river management projects

    NARCIS (Netherlands)

    Warner, J.F.

    2008-01-01

    The study thus analyses and organises how states oscillate between security logic (‘logic of war’) and non-security logic (‘logic of peace’) in flood security governance. The way floods are managed and politicised are a reflection of how society is organised. Therefore, one should look at flood prot

  8. Flood management in the Lower Incomati river basin, Mozambique: Two alternatives

    NARCIS (Netherlands)

    van Ogtrop, Floris Frederik; Hoekstra, Arjen Ysbert; van der Meulen, Frank

    2005-01-01

    The aim of this paper is to compare two views of flood management and thus add to the present thinking of living with floods as opposed to the traditional approach of flood control. The traditional pathway has widely been adopted in developed countries and aims to control floodwaters by means of

  9. Flood management in the Lower Incomati river basin, Mozambique: Two alternatives

    NARCIS (Netherlands)

    Ogtrop, van Floris Frederik; Hoekstra, Arjen Y.; Meulen, van der Frank

    2005-01-01

    The aim of this paper is to compare two views of flood management and thus add to the present thinking of living with floods as opposed to the traditional approach of flood control. The traditional pathway has widely been adopted in developed countries and aims to control floodwaters by means of dam

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

    Science.gov (United States)

    Hooke, J. M.

    2015-12-01

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

  11. Spatiotemporal review of the torrential flood phenomenon in the Morava river basin

    Directory of Open Access Journals (Sweden)

    Petrović Ana M.

    2015-01-01

    Full Text Available Phenomenon of torrential floods as the most destructive and the most frequent natural hazards in Serbia with serious socioeconomic, cultural and environmental consequences deserve special attention. In this paper, data collection strategy and data analysis with the aim of spatiotemporal characterization of the torrential flood phenomenon in the largest national, Morava river basin, are presented. A dataset (derived from the Inventory of torrential floods in Serbia of 479 registered torrential flood events with over 84 casualties for the period 1926-2013 is presented. Monthly distribution of registered torrential floods indicates that the majority of events with the highest share of death toll occurred in the late spring, from May to the end of June. According to the annual distribution there is a linear increase of torrential flood occurrence in the course of 88 years, but decrease of death toll is found. The greatest number of torrential flood events and casualties is registered in the Južna Morava river basin (watersheds of Nišava, Toplica, Veternica, Jablanica. The results of this work can be of great value in the implementation of the Flood Directive of the European Commission on a river basin level as well as for the future natural hazards information system in Serbia. [Projekat Ministarstva nauke Republike Srbije, br. 47007III

  12. Flood-inundation maps for the White River near Edwardsport, Indiana

    Science.gov (United States)

    Fowler, Kathleen K.

    2014-01-01

    Digital flood-inundation maps for a 3.3-mile reach of the White River near Edwardsport, (Ind.), 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/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at USGS streamgage 03360730, White River near Edwardsport, Ind. Near-real-time stages at this streamgage may be obtained from the USGS National Water Information System at http://waterdata.usgs.gov/ or the National Weather Service Advanced Hydrologic Prediction Service at http://water.weather.gov/ahps/, which also forecasts flood hydrographs at this site (site EDWI3.)

  13. THE FREQUENCY OF OCCURRENCE OF FLASH FLOODS ON THE RIVERS IN THE LAND OF DORNA

    Directory of Open Access Journals (Sweden)

    MIHALCA Izabela Amalia

    2015-06-01

    Full Text Available Flash floods are extreme natural phenomena that determine numerous property damage and loss of human life on both global and local level. In order to highlight not only the frequency of occurrence of floods on the rivers in the Land of Dorna but also their effects on the community, we set ourselves to perform a secondary analysis of data provided by Siret River Basin Administration. As a result, one can observe that the highest frequency of occurrence of flash floods in the region of Dorna is in the spring. During the same period of time (from 1993 to 2003 there were recorded only significant property damages after the flash floods. At the end of this paper we suggested a series of coherent measures in order to combat the negative effects of flash floods.

  14. Variations of Dissolved Iron in the Amur River During an Extreme Flood Event in 2013

    Institute of Scientific and Technical Information of China (English)

    YAN Baixing; GUAN Jiunian; Vladimir SHESTERKIN; ZHU Hui

    2016-01-01

    As a key factor limiting primary productivity in marine ecosystem,dissolved iron (DFe) export from fluvial systems has increased recently.There is particular concern about discharges of DFe during extreme flooding,when they are thought to increase considerably.An extreme flood event that caused inundation of extensive areas of Far Eastern Russia and Northeastern China occurred in the basin of the Amur River during summer and autumn 2013.During this event,water samples were collected in the middle reaches of the Amur River and the lower reaches at Khabarovsk City and analyzed for DFe concentrations and other aquatic parameters.The resuits show that the average DFe concentrations in the middle reaches of the Amur River (right bank) and at Khabarovsk were 1.11 mg/L and 0.32 mg/L,respectively,during the extreme flood in 2013.The total discharge of DFe during the flood event was 6.25 x 104 t.The high discharge of DFe during the flood reflects the elevated discharge of the river,hydrologically connected riparian wetlands,vast quantities of terrestrial runoff,and flood discharges from the Zeya and Bureya reservoirs.These results show that long-term monitoring is needed to identify and assess the impacts of DFe transport on the downstream reaches,estuarine area,and coastal ecosystems of the Amur River.

  15. Evaluation of social vulnerability to floods in Huaihe River basin: a methodology based on catastrophe theory

    Science.gov (United States)

    You, W. J.; Zhang, Y. L.

    2015-08-01

    Huaihe River is one of the seven largest rivers in China, in which floods occurred frequently. Disasters cause huge casualties and property losses to the basin, and also make it famous for high social vulnerability to floods. Based on the latest social-economic data, the index system of social vulnerability to floods was constructed, and Catastrophe theory method was used in the assessment process. The conclusion shows that social vulnerability as a basic attribute attached to urban environment, with significant changes from city to city across the Huaihe River basin. Different distribution characteristics are present in population, economy, flood prevention vulnerability. It is important to make further development of social vulnerability, which will play a positive role in disaster prevention, improvement of comprehensive ability to respond to disasters.

  16. Using seismic arrays to quantify the physics of a glacial outburst flood and its legacy on upland river dynamics

    Science.gov (United States)

    Gimbert, Florent; Cook, Kristen; Andermann, Christoff; Hovius, Niels; Turowski, Jens

    2017-04-01

    In the Himalayas fluvial erosion is thought to be controlled by the intense annual Indian Summer Monsoon precipitation. However, this region is also exposed to catastrophic floods generated by the sudden failure of landslides or moraine dams. These floods are rare and particularly devastating. Thus they have a strong impact on rivers and adjacent hillslopes, and they represent a hazard for local populations. Due to the difficulties to observe these floods and quantify their physics using traditional methods, their importance for the long-term evolution of Himalayan Rivers remains largely unknown, and no consistent early warning system exists to anticipate these events, especially in trans-boundary regions. Here we show that seismic arrays can be used to (i) reliably anticipate outburst floods and to (ii) quantify multiple and key fluvial processes associated with their propagation and their lasting impacts on upland river dynamics. We report unique seismic observations of a glacial lake outburst flood event that occurred the 5th of July 2016 in the Bhote Koshi River (Central Nepal). Precursory seismic signals are identified from the onset of the lake drainage event such that an early warning alarm may be turned on about an hour before the outburst flood wave reaches areas with an exposed population. Using our network of stations we observe for the first time that the outburst flood wave is in fact made of two distinct waves, namely a water flow wave and a bedload sediment wave. As expected these two waves travel at different speeds. We find that the ratio between the two wave speeds matches with that previously found at much smaller scales in flume laboratory experiments. Based on the physical modelling of both water-flow- and bedload- induced seismic noise we provide estimates of flow depth and bedload transport characteristics (flux, moving grains sizes) prior, during and after the flood. In particular we show that bedload sediment flux is enhanced by up to a

  17. Effects of global warming on floods and droughts and related water quality of rivers

    NARCIS (Netherlands)

    De Jong, B.

    2006-01-01

    This review focuses on the effect of global warming on droughts, rainstorms and floods and related water quality of rivers. Relations of temperature, rainstorms and river discharges with water quality variables like water temperature, chemical concentrations and microbiological activity are discusse

  18. Scale orientated analysis of river width changes due to extreme flood hazards

    Directory of Open Access Journals (Sweden)

    G. Krapesch

    2011-08-01

    Full Text Available This paper analyses the morphological effects of extreme floods (recurrence interval >100 years and examines which parameters best describe the width changes due to erosion based on 5 affected alpine gravel bed rivers in Austria. The research was based on vertical aerial photos of the rivers before and after extreme floods, hydrodynamic numerical models and cross sectional measurements supported by LiDAR data of the rivers. Average width ratios (width after/before the flood were calculated and correlated with different hydraulic parameters (specific stream power, shear stress, flow area, specific discharge. Depending on the geomorphological boundary conditions of the different rivers, a mean width ratio between 1.12 (Lech River and 3.45 (Trisanna River was determined on the reach scale. The specific stream power (SSP best predicted the mean width ratios of the rivers especially on the reach scale and sub reach scale. On the local scale more parameters have to be considered to define the "minimum morphological spatial demand of rivers", which is a crucial parameter for addressing and managing flood hazards and should be used in hazard zone plans and spatial planning.

  19. Temporal clustering of floods and impacts of climate indices in the Tarim River basin, China

    Science.gov (United States)

    Gu, Xihui; Zhang, Qiang; Singh, Vijay P.; Chen, Yongqin David; Shi, Peijun

    2016-12-01

    The occurrence rates of floods in Tarim River basin, the largest arid basin in China, were estimated using the Peak-over-Threshold (POT) technique. The intra-annual, seasonal and inter-annual clustering of floods was then analyzed using the Cox regression model, month frequency method and dispersion index, respectively. Possible impacts of climate indices on the occurrence rates were also investigated. Both NAO and AO are selected as significant covariates to occurrence rates of floods in Tarim River basin by Cox regression model, suggesting occurrence of flood events is not independent, but exhibits temporal clustering in intra-annual scale. On the basis of the results of the station and region-wide modeling by Cox regression model, we suggest using a model in which the rate of occurrence depends on monthly averaged NAO or AO. The Cox regression model not only can be used to assess the time-varying rate of flood occurrence, but also has the capability to forecast the predictors. Flood occurrence time and probability of exceedance are changing with climate index from negative to positive on both station and region scale. In addition, seasonal clustering of station-based floods and regional observed floods are also identified with mainly concentrating from June to August. Meanwhile, dispersion index is used to evaluate the inter-annual clustering of annual number of flood occurrences both on station and region. We found that inter-annual clustering of regional floods is more evident than that of station-based floods, indicating that regional observed flood records are generally over-dispersed with a tendency for flood events to cluster in time.

  20. Joint modelling of flood peaks and volumes: A copula application for the Danube River

    Directory of Open Access Journals (Sweden)

    Papaioannou George

    2016-12-01

    Full Text Available Flood frequency analysis is usually performed as a univariate analysis of flood peaks using a suitable theoretical probability distribution of the annual maximum flood peaks or peak over threshold values. However, other flood attributes, such as flood volume and duration, are necessary for the design of hydrotechnical projects, too. In this study, the suitability of various copula families for a bivariate analysis of peak discharges and flood volumes has been tested. Streamflow data from selected gauging stations along the whole Danube River have been used. Kendall’s rank correlation coefficient (tau quantifies the dependence between flood peak discharge and flood volume settings. The methodology is applied to two different data samples: 1 annual maximum flood (AMF peaks combined with annual maximum flow volumes of fixed durations at 5, 10, 15, 20, 25, 30 and 60 days, respectively (which can be regarded as a regime analysis of the dependence between the extremes of both variables in a given year, and 2 annual maximum flood (AMF peaks with corresponding flood volumes (which is a typical choice for engineering studies. The bivariate modelling of the extracted peak discharge - flood volume couples is achieved with the use of the Ali-Mikhail-Haq (AMH, Clayton, Frank, Joe, Gumbel, Hüsler-Reiss, Galambos, Tawn, Normal, Plackett and FGM copula families. Scatterplots of the observed and simulated peak discharge - flood volume pairs and goodness-of-fit tests have been used to assess the overall applicability of the copulas as well as observing any changes in suitable models along the Danube River. The results indicate that for the second data sampling method, almost all of the considered Archimedean class copula families perform better than the other copula families selected for this study, and that for the first method, only the upper-tail-flat copulas excel (except for the AMH copula due to its inability to model stronger relationships.

  1. Flood-inundation maps for the North Branch Elkhart River at Cosperville, Indiana

    Science.gov (United States)

    Kim, Moon H.; Johnson, Esther M.

    2014-01-01

    Digital flood-inundation maps for a reach of the North Branch Elkhart River at Cosperville, Indiana (Ind.), were created by the U.S. Geological Survey (USGS) in cooperation with the U.S. Army Corps of Engineers, Detroit District. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/ depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at USGS streamgage 04100222, North Branch Elkhart River at Cosperville, Ind. Current conditions for estimating near-real-time areas of inundation using USGS streamgage information may be obtained on the Internet at http://waterdata.usgs.gov/in/nwis/uv?site_no=04100222. In addition, information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system (http:/water.weather.gov/ahps/). The NWS AHPS forecasts flood hydrographs at many places that are often colocated with USGS streamgages, including the North Branch Elkhart River at Cosperville, Ind. NWS AHPS-forecast peak-stage information may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. For this study, flood profiles were computed for the North Branch Elkhart River reach by means of a one-dimensional step-backwater model. The hydraulic model was calibrated by using the most current stage-discharge relations at USGS streamgage 04100222, North Branch Elkhart River at Cosperville, Ind., and preliminary high-water marks from the flood of March 1982. The calibrated hydraulic model was then used to determine four water-surface profiles for flood stages at 1-foot intervals referenced to the streamgage datum and ranging from bankfull to the highest stage of the current stage-discharge rating curve. The simulated water-surface profiles were then combined with a geographic information system (GIS

  2. Integrated Flood Risk Assessment of Rural Communities in the Oti River Basin, West Africa

    Directory of Open Access Journals (Sweden)

    Kossi Komi

    2016-11-01

    Full Text Available Flood damage in West Africa has increased appreciably during the last two decades. Poor communities are more at risk due to the vulnerability of their livelihoods, especially in rural areas where access to services and infrastructures is limited. The aim of this paper is to identify the main factors that contribute to flood risk of rural communities in the Oti River Basin, Togo. A community-based disaster risk index model is applied. The analyses use primary data collected through questionnaires during fieldwork, the analytic hierarchy process (AHP method, population and housing census data and flood hazard mapping of the study area. The results showed a moderate level of flood risk despite a high level of hazard and vulnerability for all investigated communities. In addition, the results suggest that decreasing vulnerability through creation of new income-generating opportunities and increasing capacity of communities to manage their own flood risk should be paramount in order to reduce flood risk in the study area. The results of this work contribute to the understanding of flood risk and can be used to identify, assess, and compare flood-prone areas, as well as simulating the impacts of flood management measures in the Oti River Basin.

  3. The Upper Mississippi River floodscape: spatial patterns of flood inundation and associated plant community distributions

    Science.gov (United States)

    DeJager, Nathan R.; Rohweder, Jason J.; Yin, Yao; Hoy, Erin E.

    2016-01-01

    Questions How is the distribution of different plant communities associated with patterns of flood inundation across a large floodplain landscape? Location Thirty-eight thousand nine hundred and seventy hectare of floodplain, spanning 320 km of the Upper Mississippi River (UMR). Methods High-resolution elevation data (Lidar) and 30 yr of daily river stage data were integrated to produce a ‘floodscape’ map of growing season flood inundation duration. The distributions of 16 different remotely sensed plant communities were quantified along the gradient of flood duration. Results Models fitted to the cumulative frequency of occurrence of different vegetation types as a function of flood duration showed that most types exist along a continuum of flood-related occurrence. The diversity of community types was greatest at high elevations (0–10 d of flooding), where both upland and lowland community types were found, as well as at very low elevations (70–180 d of flooding), where a variety of lowland herbaceous communities were found. Intermediate elevations (20–60 d of flooding) tended to be dominated by floodplain forest and had the lowest diversity of community types. Conclusions Although variation in flood inundation is often considered to be the main driver of spatial patterns in floodplain plant communities, few studies have quantified flood–vegetation relationships at broad scales. Our results can be used to identify targets for restoration of historical hydrological regimes or better anticipate hydro-ecological effects of climate change at broad scales.

  4. Challenges of flood monitoring in the Senegal river valley using multi-temporal data

    Science.gov (United States)

    Bruckmann, Laurent; Delbart, Nicolas

    2017-04-01

    In Sub-Saharan Africa, floodplains wetlands play an important role for livelihoods and economy, especially for agriculture and fishing. However, tropical rivers flows are increasingly modified by climate change and dam regulation. In the Senegal river valley, the annual flood, from August to November, is an important water resources creating ecosystems services for people. Senegal river basin face to hydrological changes, due to rainfall diminution during the 1970's and building of large dams during 1980's to secure water resources. Water management and development of irrigation have modified the floodplain functioning. Flood recession agriculture, grazing and fishing are now confronted to a high uncertainty about floods level, duration and extension. Thus, spatiotemporal information of flood extension and duration are important for local communities and stakeholders to ensure food security and ecosystems services. Multi-temporal satellite data demonstrates an important applicability for flood mapping. Aims of this work is to present potentiality of using multi-temporal data from MODIS and new satellite Sentinel-2 for flood monitoring in a Sahelian context. It will also discuss the potential of flood mapping for the analysis of the dynamics of riparian vegetation and flood recession agriculture. This study uses two datasets to explore flood monitoring in Senegal river valley. Firstly, MODIS 8-days data (MOD09A) are first used, because of its temporal resolution of 8 days covering the period from 2000 to 2016. However, MODIS data are limited due to a low spatial resolution, that's why we also use Sentinel-2 data, available since summer 2015. The data were processed by constructing NDWI time-series (NDWI threshold is empirically defined) and extracting NDWI values for each inundated pixel during flood. First results demonstrate that using MODIS on a large scale is enough for analyze interannual variability of the flooded surfaces. We present here maps of flood

  5. Sedimentary record of Warta river floods in summer 2010 and winter 2011 nearby Poznan, W Poland

    Science.gov (United States)

    Skolasińska, Katarzyna; Szczuciński, Witold; Mitręga, Marta; Rotnicka, Joanna; Jagodziński, Robert; Lorenc, Stanisław

    2013-04-01

    The Warta River valley nearby Poznań (W Poland) represents a meandering lowland river changed during the last 150 years by hydro-engineering works. Floods represent a major natural hazard in the region. However, historical records are not complete - particularly for former rural areas. Thus, sedimentary record may potentially offer additional insights into the flooding history. The big floods in the summer 2010 (the largest during the last 31 years) and winter 2011 offered opportunity to study their sedimentary record. The particular purposes were to identify sedimentary characteristics of summer and winter floods, interpret various phases of particular floods in the record, and assess impact of early post-depositional changes of the flood deposits. The surveys were conducted in six areas just after the floods and were repeated after several months, one and two years. The deposits spatial extent, thickness, surface bedforms and sediment type were assessed in the field. Sediment samples were further investigated for grain size distribution, organic matter content, roundness and sand grains surface features (SEM). The sandy flood deposits mostly build natural levee, side bars (climbing ripple lamination and planar cross laminations (only in crevasse splays). Vertical grain size changes in levee deposits revealed pensymmetric and/or reverse grading interpreted as effect of changing velocity during the rising water level. The sand grains were similar to the river channel sands and dominated by polished and sub-rounded quartz grains with preserved dissolution and dulled surface microfeatures. Further from the channel bank (few to few hundreds of meters) only discontinuous up to few mm thick organic rich mud layer was left, which after the summer flood was covered by algal mats. However the mud and mats were quickly reworked by new vegetation. The follow up surveys revealed that the preservation potential of flood deposits is low to moderate (only for sandy deposits

  6. Flood-inundation maps for the East Fork White River at Shoals, Indiana

    Science.gov (United States)

    Boldt, Justin A.

    2016-05-06

    Digital flood-inundation maps for a 5.9-mile reach of the East Fork White River at Shoals, Indiana (Ind.), were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/ depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage on the East Fork White River at Shoals, Ind. (USGS station number 03373500). 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 (AHPS) at http://water.weather.gov/ahps/, which also forecasts flood hydrographs at this site (NWS AHPS site SHLI3). NWS AHPS forecast peak stage information may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation.Flood profiles were computed for the East Fork White River reach by means of a one-dimensional, step-backwater model developed by the U.S. Army Corps of Engineers. The hydraulic model was calibrated by using the current stage-discharge relation (USGS rating no. 43.0) at USGS streamgage 03373500, East Fork White River at Shoals, Ind. The calibrated hydraulic model was then used to compute 26 water-surface profiles for flood stages at 1-foot (ft) intervals referenced to the streamgage datum and ranging from approximately bankfull (10 ft) to the highest stage of the current stage-discharge rating curve (35 ft). The simulated water-surface profiles were then combined with a geographic information system (GIS) digital elevation model (DEM), derived from light detection and ranging (lidar) data, to delineate the area flooded at each water level. The areal extent of the 24-ft flood-inundation map was

  7. Combined impact of global river-floods and tropical cyclones on long-term economic growth

    Science.gov (United States)

    Geiger, Tobias; Piontek, Franziska; Frieler, Katja

    2016-04-01

    Worldwide direct economic losses associated with the impact of river-floods and tropical cyclones have seen a rapid increase over time. Their nominal impact is projected to rise even further as the exposed population grows, per capita income increases, and anthropogenic climate change manifests. Beyond the immediate damage of each event, indirect economic impacts can affect growth trajectories of countries as a whole for many years after the disaster. Whether the cumulated indirect effects stimulate or hinder economic growth in the long-run is so far undecided as previous studies find contradicting results depending on the analysed hazard and the underlying methodology. We here combine two types of the costliest meteorological disasters worldwide in order to gain certainty on their joint impact in a comprehensive way. Relative affected population by country and year is determined based on historical tropical cyclone tracks (IBTrACS) and historical simulations of river-flood return periods forced by observed weather and used as a predictor for the disaster's impact on national Gross Domestic Product (GDP) time series. Controlling for various non-disaster related effects, we find a cumulated GDP deficit that remains robust for more than a decade after the event.

  8. Climate Change Impact Assessment of Dike Safety and Flood Risk in the Vidaa River System

    DEFF Research Database (Denmark)

    Madsen, H.; Sunyer Pinya, Maria Antonia; Larsen, J.;

    2013-01-01

    The impact of climate change on the flood risk and dike safety in the Vidaa River system, a cross-border catchment located in the southern part of Jutland, Denmark and northern Germany, is analysed. The river discharges to the Wadden Sea through a tidal sluice, and extreme water level conditions......, and increases in storm surge levels of up to 0.8 m in 2100 are estimated. The changes in extreme catchment run-off and sea water level have a significant effect on the flood risk in the river system. While most parts today have a low risk of dike overtopping with annual exceedance probabilities of 0.1 % or less...

  9. Impact of a large flood on mountain river habitats, channel morphology, and valley infrastructure

    Science.gov (United States)

    Hajdukiewicz, Hanna; Wyżga, Bartłomiej; Mikuś, Paweł; Zawiejska, Joanna; Radecki-Pawlik, Artur

    2016-11-01

    The Biała River, Polish Carpathians, was considerably modified by channelization and channel incision in the twentieth century. To restore the Biała, establishing an erodible corridor was proposed in two river sections located in its mountain and foothill course. In these sections, longer, unmanaged channel reaches alternate with short, channelized reaches; and channel narrowing and incision increases in the downstream direction. In June 2010 an 80-year flood occurred on the river; and this study aims at determining its effects on physical habitat conditions for river biota, channel morphology, and valley-floor infrastructure. Surveys of 10 pairs of closely located, unmanaged and channelized cross sections, performed in 2009 and in the late summer 2010, allowed us to assess the flood-induced changes to physical habitat conditions. A comparison of channel planforms determined before (2009) and after (2012) the flood provided information on the degree of channel widening as well as changes in the width of particular elements of the river's active zone in eight stretches of the Biała. The impact of the flood on valley-floor infrastructure was confronted with the degree of river widening in unmanaged and channelized river reaches. Before the flood, unmanaged cross sections were typified by finer bed material and greater lateral variability in depth-averaged and near-bed flow velocity than channelized cross sections. The flood tended to equalize habitat conditions in both types of river cross sections, obliterating differences (in particular physical habitat parameters) between channelized and unmanaged channel reaches. River widening mostly reflected an increase in the area of channel bars, whereas the widening of low-flow channels was less pronounced. A comparison of channel planform from 2009 and 2012 indicated that intense channel incision typical of downstream sections limited river widening by the flood. Active channel width increased by half in the unmanaged

  10. Torrent floodplain mapping and torrent flood control in Serbia in the conditions of economic crisis

    Science.gov (United States)

    Gavrilovic, Z.; Stefanovic, M.

    2009-04-01

    investments. This paper will present the realised results of low-budget mapping of flood zones of torrents and other waterways and the realised preventive techniques of torrential flood control, which were successfully implemented during the great flood of the Danube in 2006. On that occasion, numerous torrential floods endangered the defence system of the river Danube. Key words: Floodplain, flood, torrent, flood defence.

  11. Sept 2013 NFHL 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...

  12. 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

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

    Science.gov (United States)

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

    2016-08-01

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

  14. Flood-inundation maps for the Mississinewa River at Marion, Indiana, 2013

    Science.gov (United States)

    Coon, William F.

    2014-01-01

    Digital flood-inundation maps for a 9-mile (mi) reach of the Mississinewa River from 0.75 mi upstream from the Pennsylvania Street bridge in Marion, Indiana, to 0.2 mi downstream from State Route 15 were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The flood inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage on the Mississinewa River at Marion (station number 03326500). 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 at http://water.weather.gov/ahps/, which also forecasts flood hydrographs at this site. Flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The model was calibrated by using the current stage-discharge relation at the Mississinewa River streamgage, in combination with water-surface profiles from historic floods and from the current (2002) flood-insurance study for Grant County, Indiana. The hydraulic model was then used to compute seven water-surface profiles for flood stages at 1-fo (ft) intervals referenced to the streamgage datum and ranging from 10 ft, which is near bankfull, to 16 ft, which is between the water levels associated with the estimated 10- and 2-percent annual exceedance probability floods (floods with recurrence interval between 10 and 50 years) and equals the “major flood stage” as defined by the NWS. 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 0.98 ft vertical accuracy and 4.9 ft

  15. Flood susceptible analysis at Kelantan river basin using remote sensing and logistic regression model

    Science.gov (United States)

    Pradhan, Biswajeet

    Recently, in 2006 and 2007 heavy monsoons rainfall have triggered floods along Malaysia's east coast as well as in southern state of Johor. The hardest hit areas are along the east coast of peninsular Malaysia in the states of Kelantan, Terengganu and Pahang. The city of Johor was particularly hard hit in southern side. The flood cost nearly billion ringgit of property and many lives. The extent of damage could have been reduced or minimized if an early warning system would have been in place. This paper deals with flood susceptibility analysis using logistic regression model. We have evaluated the flood susceptibility and the effect of flood-related factors along the Kelantan river basin using the Geographic Information System (GIS) and remote sensing data. Previous flooded areas were extracted from archived radarsat images using image processing tools. Flood susceptibility mapping was conducted in the study area along the Kelantan River using radarsat imagery and then enlarged to 1:25,000 scales. Topographical, hydrological, geological data and satellite images were collected, processed, and constructed into a spatial database using GIS and image processing. The factors chosen that influence flood occurrence were: topographic slope, topographic aspect, topographic curvature, DEM and distance from river drainage, all from the topographic database; flow direction, flow accumulation, extracted from hydrological database; geology and distance from lineament, taken from the geologic database; land use from SPOT satellite images; soil texture from soil database; and the vegetation index value from SPOT satellite images. Flood susceptible areas were analyzed and mapped using the probability-logistic regression model. Results indicate that flood prone areas can be performed at 1:25,000 which is comparable to some conventional flood hazard map scales. The flood prone areas delineated on these maps correspond to areas that would be inundated by significant flooding

  16. Integrating a Typhoon Event Database with an Optimal Flood Operation Model on the Real-Time Flood Control of the Tseng-Wen Reservoir

    Science.gov (United States)

    Chen, Y. W.; Chang, L. C.

    2012-04-01

    Typhoons which normally bring a great amount of precipitation are the primary natural hazard in Taiwan during flooding season. Because the plentiful rainfall quantities brought by typhoons are normally stored for the usage of the next draught period, the determination of release strategies for flood operation of reservoirs which is required to simultaneously consider not only the impact of reservoir safety and the flooding damage in plain area but also for the water resource stored in the reservoir after typhoon becomes important. This study proposes a two-steps study process. First, this study develop an optimal flood operation model (OFOM) for the planning of flood control and also applies the OFOM on Tseng-wun reservoir and the downstream plain related to the reservoir. Second, integrating a typhoon event database with the OFOM mentioned above makes the proposed planning model have ability to deal with a real-time flood control problem and names as real-time flood operation model (RTFOM). Three conditions are considered in the proposed models, OFOM and RTFOM, include the safety of the reservoir itself, the reservoir storage after typhoons and the impact of flooding in the plain area. Besides, the flood operation guideline announced by government is also considered in the proposed models. The these conditions and the guideline can be formed as an optimization problem which is solved by the genetic algorithm (GA) in this study. Furthermore, a distributed runoff model, kinematic-wave geomorphic instantaneous unit hydrograph (KW-GIUH), and a river flow simulation model, HEC-RAS, are used to simulate the river water level of Tseng-wun basin in the plain area and the simulated level is shown as an index of the impact of flooding. Because the simulated levels are required to re-calculate iteratively in the optimization model, applying a recursive artificial neural network (recursive ANN) instead of the HEC-RAS model can significantly reduce the computational burden of

  17. Global assessment of river flood protection benefits and corresponding residual risks under climate change

    Science.gov (United States)

    Lim, Wee Ho; Yamazaki, Dai; Koirala, Sujan; Hirabayashi, Yukiko; Kanae, Shinjiro; Dadson, Simon J.; Hall, Jim W.

    2016-04-01

    Global warming increases the water-holding capacity of the atmosphere and this could lead to more intense rainfalls and possibly increasing natural hazards in the form of flooding in some regions. This implies that traditional practice of using historical hydrological records alone is somewhat limited for supporting long-term water infrastructure planning. This has motivated recent global scale studies to evaluate river flood risks (e.g., Hirabayashi et al., 2013, Arnell and Gosling, 2014, Sadoff et al., 2015) and adaptations benefits (e.g., Jongman et al., 2015). To support decision-making in river flood risk reduction, this study takes a further step to examine the benefits and corresponding residual risks for a range of flood protection levels. To do that, we channelled runoff information of a baseline period (forced by observed hydroclimate conditions) and each CMIP5 model (historic and future periods) into a global river routing model called CaMa-Flood (Yamazaki et al., 2011). We incorporated the latest global river width data (Yamazaki et al., 2014) into CaMa-Flood and simulate the river water depth at a spatial resolution of 15 min x 15 min. From the simulated results of baseline period, we use the annual maxima river water depth to fit the Gumbel distribution and prepare the return period-flood risk relationship (involving population and GDP). From the simulated results of CMIP5 model, we also used the annual maxima river water depth to obtain the Gumbel distribution and then estimate the exceedance probability (historic and future periods). We apply the return period-flood risk relationship (above) to the exceedance probability and evaluate the flood protection benefits. We quantify the corresponding residual risks using a mathematical approach that is consistent with the modelling structure of CaMa-Flood. Globally and regionally, we find that the benefits of flood protection level peak somewhere between 20 and 500 years; residual risks diminish

  18. Development of flood-inundation maps for the Mississippi River in Saint Paul, Minnesota

    Science.gov (United States)

    Czuba, Christiana R.; Fallon, James D.; Lewis, Corby R.; Cooper, Diane F.

    2014-01-01

    Digital flood-inundation maps for a 6.3-mile reach of the Mississippi River in Saint Paul, Minnesota, were developed through a multi-agency effort by the U.S. Geological Survey in cooperation with the U.S. Army Corps of Engineers and in collaboration with the National Weather Service. The inundation maps, which can be accessed through the U.S. Geological Survey Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/ and the National Weather Service Advanced Hydrologic Prediction Service site at http://water.weather.gov/ahps/inundation.php, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the U.S. Geological Survey streamgage at the Mississippi River at Saint Paul (05331000). The National Weather Service forecasted peak-stage information at the streamgage may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the Mississippi River by means of a one-dimensional step-backwater model. The hydraulic model was calibrated using the most recent stage-discharge relation at the Robert Street location (rating curve number 38.0) of the Mississippi River at Saint Paul (streamgage 05331000), as well as an approximate water-surface elevation-discharge relation at the Mississippi River at South Saint Paul (U.S. Army Corps of Engineers streamgage SSPM5). The model also was verified against observed high-water marks from the recent 2011 flood event and the water-surface profile from existing flood insurance studies. The hydraulic model was then used to determine 25 water-surface profiles for flood stages at 1-foot intervals ranging from approximately bankfull stage to greater than the highest recorded stage at streamgage 05331000. The simulated water-surface profiles were then combined with a geographic information system digital elevation model, derived from high-resolution topography

  19. Effects of an extreme flood on trace elements in river water—From urban stream to major river basin

    Science.gov (United States)

    Barber, Larry B.; Paschke, Suzanne; Battaglin, William A.; Douville, Chris; Fitzgerald, Kevin C.; Keefe, Steffanie H.; Roth, David A.; Vajda, Alan M.

    2017-01-01

    Major floods adversely affect water quality through surface runoff, groundwater discharge, and damage to municipal water infrastructure. Despite their importance, it can be difficult to assess the effects of floods on streamwater chemistry because of challenges collecting samples and the absence of baseline data. This study documents water quality during the September 2013 extreme flood in the South Platte River, Colorado, USA. Weekly time-series water samples were collected from 3 urban source waters (municipal tap water, streamwater, and wastewater treatment facility effluent) under normal-flow and flood conditions. In addition, water samples were collected during the flood at 5 locations along the South Platte River and from 7 tributaries along the Colorado Front Range. Samples were analyzed for 54 major and trace elements. Specific chemical tracers, representing different natural and anthropogenic sources and geochemical behaviors, were used to compare streamwater composition before and during the flood. The results differentiate hydrological processes that affected water quality: (1) in the upper watershed, runoff diluted most dissolved constituents, (2) in the urban corridor and lower watershed, runoff mobilized soluble constituents accumulated on the landscape and contributed to stream loading, and (3) flood-induced groundwater discharge mobilized soluble constituents stored in the vadose zone.

  20. Flood risk trends in coastal watersheds in South Spain: direct and indirect impact of river regulation

    Science.gov (United States)

    Egüen, M.; Polo, M. J.; Gulliver, Z.; Contreras, E.; Aguilar, C.; Losada, M. A.

    2015-06-01

    Spain is one of the world's countries with a large number of reservoirs per inhabitant. This intense regulation of the fluvial network during the 20th century has resulted in a decrease in flood events, a higher availability of water resources, and a high development of the irrigated crop area, even in the drier regions. For decades, flood perception was reduced since the development of reservoirs protected the floodplains of river; this resulted in later occupation of soil by urban, agricultural and industrial uses. In recent years, an increasing perception of flood events is observed, associated to the higher damage associated to extreme events in the now occupied areas, especially in coastal watersheds. This work shows the change on flood risk in the coastal areas of three hydrographic basins in Andalusia (South Spain) during the reservoir expansion period: the Guadalete, Guadalquivir and Guadalhorce river basins. The results differentiate the impact of the regulation level on both the cumulative distribution functions of the fluvial discharge near the river mouth, for different time scales, and the associated damage related to the enhanced soil occupation during this period. The different impact on the final medium and long term flood risk is also assessed in terms of the storage capacity per unit area throughout the basins, the effective annual runoff/precipitation index, the frequency of sea storms, and the human factor (change in social perception of floods), for different intervals in the flood extreme regime. The implications for adaptation actions is also assessed.

  1. Floods of May 1959 in the Au Gres and Rifle River basins, Michigan

    Science.gov (United States)

    Stoimenoff, L.E.

    1960-01-01

    The floods of May 1959 in the Au Gres and Rifle River basins, Michigan, resulted from heavy rainfall during the night of May 19-20. Peak unit discharges for small drainage areas (less than about 15 square miles) were the highest ever measured in the Lower Peninsula of Michigan, and for very small areas (about one square mile) were of the same order of magnitude as those for the record Ontonagon River flood of August 1942 in the Upper Peninsula.Because the flood area is sparsely populated, damages were largely confined to farm lands and facilities and to secondary roads and their appurtenant drainage structures.The U. S. Geological Survey, through the district office in Lansing, Michigan, operates a network of streamgaging stations and crest-stage stations in the area affected by this flood. Six recording rain gages are operated in the upper Rifle River basin. Most of the gaging stations have been in operation for 7 to 9 years giving systematic records of stage, discharge, and volume of flow covering the range from drought to flood. This report contains records of-stage and discharge at 9 gaging stations for the floodperiod, peak discharges at 7 crest-stage stationsand 2 miscellaneous sites within the flood area, andother data pertinent to the flood.

  2. Effects of a test flood on fishes of the Colorado River in Grand Canyon, Arizona

    Science.gov (United States)

    Valdez, R.A.; Hoffnagle, T.L.; McIvor, C.C.; McKinney, T.; Leibfried, W.C.

    2001-01-01

    A beach/habitat-building flow (i.e., test flood) of 1274 m3/s, released from Glen Canyon Dam down the Colorado River through Grand Canyon, had little effect on distribution, abundance, or movement of native fishes, and only short-term effects on densities of some nonnative species Shoreline and backwater catch rates of native fishes, including juvenile humpback chub (Gila cypha), flannelmouth suckers (Catostomus latipinnis), and bluehead suckers (C. discobolus), and all ages of speckled dace (Rhinichthys osculus), were not significantly different before and after the flood. Annual spring spawning migrations of flannelmouth suckers into the Paria River and endangered humpback chub into the Little Colorado River (LCR) took place during and after the flood, indicating no impediment to fish migrations. Pre-spawning adults staged in large slack water pools formed at the mouths of these tributaries during the flood. Net movement and habitat used by nine radio-tagged adult humpback chub during the flood were not significantly different from prior observations. Diet composition of adult humpback chub varied, but total biomass did not differ significantly before, during, and after the flood, indicating opportunistic feeding for a larger array of available food items displaced by the flood. Numbers of nonnative rainbow trout (Oncorhynchus mykiss) disadvantage alien predators and competitors and enhance survival of native fishes.

  3. Solid transport in mountain rivers: monitoring techniques and long term assessment as flood prevention tools

    Science.gov (United States)

    Longoni, Laura; Brambilla, Davide; Ivanov, Vladislav; Messa, Giacomo; Veronelli, Andrea; Radice, Alessio; Papini, Monica

    2017-04-01

    Floods are calamitous phenomena with an ever-increasing frequency around the globe, that often result in socio-economic damage and casualties. The role of the solid fraction in the river dynamic has been widely debated in the last decade and its importance is recognized as critical and not negligible in flood simulations as it has been evidenced that the severity of an event is often the result of the coupling of a flood wave with elevated solid transport rates. Nevertheless, assessing the quantity of sediment mobilized in a particular event is not feasible without a long term analysis of the river's dynamics and its morphological evolution since it is defined by past events. This work is focused on the techniques to improve knowledge about sediment production and transport through hydrological networks as a necessary component of a wise flood prevention planning. In particular, a multidisciplinary approach that combines hydraulic and geological knowledge is required in order to understand the evolution of the river sediment and how it will influence the following critical event. The methods are presented through a case study in Italy where a series of different approaches have been integrated to gain a comprehensive understanding of the problem: the sediment movement has been studied by a Eulerian as well as a Lagrangian approaches while hydraulic properties of the stream have been measured. The research started with an attempt to monitor sediment movements: in June 2016 300 sample pebbles, equipped with RFID (Radio Frequency IDentification) transponders, have been deployed in the river and tracked after every major rainfall event. The obtained data-set has been combined with a morphological analysis and a river flow discharge computed through PIV (Particle Image Velocimetry) method in order to identify the relation between a given rainfall event and sediment transport. Moreover, critical sediment size has been estimated from field data using three approaches: two

  4. An expanded model: flood-inundation maps for the Leaf River at Hattiesburg, Mississippi, 2013

    Science.gov (United States)

    Storm, John B.

    2014-01-01

    Digital flood-inundation maps for a 6.8-mile reach of the Leaf River at Hattiesburg, Mississippi (Miss.), were created by the U.S. Geological Survey (USGS) in cooperation with the City of Hattiesburg, City of Petal, Forrest County, Mississippi Emergency Management Agency, Mississippi Department of Homeland Security, and the Emergency Management District. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage at Leaf River at Hattiesburg, Miss. (station no. 02473000). Current conditions for estimating near-real-time areas of inundation by use of USGS streamgage information may be obtained on the Internet at http://waterdata.usgs.gov/. In addition, the information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system (http://water.weather.gov/ahps/). The NWS forecasts flood hydrographs at many places that are often colocated with USGS streamgages. NWS-forecasted peak-stage information may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, 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 relations at the Leaf River at Hattiesburg, Miss. streamgage (02473000) and documented high-water marks from recent and historical floods. The hydraulic model was then used to determine 13 water-surface profiles for flood stages at 1.0-foot intervals referenced to the streamgage datum and ranging from bankfull to approximately the highest recorded water level at the streamgage. The simulated water-surface profiles were then combined with a geographic information system (GIS

  5. Discharge forecasting using MODIS and radar altimetry: potential application for transboundary flood risk management in Niger-Benue River basin

    Science.gov (United States)

    Tarpanelli, Angelica; Amarnath, Giriraj; Brocca, Luca; Moramarco, Tommaso

    2016-04-01

    Flooding is one of most widespread natural disasters in the world. Its impact is particularly severe and destructive in Asia and Africa, because the living conditions of some settlements are inadequate to cope with this type of natural hazard. In this context, the estimation of discharge is extremely important to address water management and flood risk assessment. However, the inadequate monitoring network hampers any control and prediction activity that could improve these disastrous situations. In the last few years, remote sensing sensors have demonstrated their effectiveness in retrieving river discharge, especially in supporting discharge nowcasting and forecasting activities. Recently, the potential of radar altimetry was apparent when used for estimating water levels in an ungauged river site with good accuracy. It has also become a very useful tool for estimation and prediction of river discharge. However, the low temporal resolution of radar altimeter observations (10 or 35 days, depending on the satellite mission) may be not suitable for day-by-day hydrological forecasting. Differently, MODerate resolution Imaging Spectroradiometer (MODIS), considering its proven potential for quantifying the variations in discharge of the rivers at daily time resolution may be more suited to this end. For these reasons, MODIS and radar altimetry data were used in this study to predicting and forecasting the river discharge along the Niger-Benue River, where severe flooding with extensive damage to property and loss of lives occurred. Therefore, an effective method to forecast flooding can support efforts towards creating an early warning system. In order to estimate river discharge, four MODIS products (daily, 8-day, and from AQUA and TERRA satellites) connected at three sites (two gauged and one ungauged) were used. The capability of remote sensing sensors to forecast discharge a few days in advance at a downstream section using MODIS and ENVISAT radar altimetry data

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

    Directory of Open Access Journals (Sweden)

    Da-wei Zhang

    2015-07-01

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

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

    Science.gov (United States)

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

    2017-09-01

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

  8. Flood-inundation maps for the East Fork White River near Bedford, Indiana

    Science.gov (United States)

    Fowler, Kathleen K.

    2014-01-01

    Digital flood-inundation maps for an 1.8-mile reach of the East Fork White River near Bedford, Indiana (Ind.) 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/ depict estimates of the areal extent and depth of flooding corresponding to selectedwater levels (stages) at USGS streamgage 03371500, East Fork White River near Bedford, Ind. Current conditions for estimating near-real-time areas of inundation using USGS streamgage information may be obtained on the Internet at http://waterdata.usgs.gov/in/nwis/uv?site_no=03371500. In addition, information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system (http://water.weather.gov/ahps/). The NWS forecasts flood hydrographs at many places that are often colocated with USGS streamgages, including the East Fork White River near Bedford, Ind. NWS-forecasted peak-stage information may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. For this study, flood profiles were computed for the East Fork White River reach by means of a one-dimensional step-backwater model. The hydraulic model was calibrated by using the most current stage-discharge relations at USGS streamgage 03371500, East Fork White River near Bedford, Ind., and documented high-water marks from the flood of June 2008. The calibrated hydraulic model was then used to determine 20 water-surface profiles for flood stages at 1-foot intervals referenced to the streamgage datum and ranging from bankfull to the highest stage of the current stage-discharge rating curve. The simulated water-surface profiles were then combined with a geographic information system (GIS) digital elevation model (DEM, derived from

  9. Modeling Flood Inundation Induced by River Flow and Storm Surges over a River Basin

    Directory of Open Access Journals (Sweden)

    Wei-Bo Chen

    2014-10-01

    Full Text Available Low-lying coastal regions and their populations are at risk during storm surge events and high freshwater discharges from upriver. An integrated storm surge and flood inundation modeling system was used to simulate storm surge and inundation in the Tsengwen River basin and the adjacent coastal area in southern Taiwan. A three-dimensional hydrodynamic model with an unstructured grid was used, which was driven by the tidal elevation at the open boundaries and freshwater discharge at the upriver boundary. The model was validated against the observed water levels for three typhoon events. The simulation results for the model were in reasonable agreement with the observational data. The model was then applied to investigate the effects of a storm surge, freshwater discharge, and a storm surge combined with freshwater discharge during an extreme typhoon event. The super Typhoon Haiyan (2013 was artificially shifted to hit Taiwan: the modeling results showed that the inundation area and depth would cause severe overbank flow and coastal flooding for a 200 year return period flow. A high-resolution grid model is essential for the accurate simulation of storm surges and inundation.

  10. Flood-inundation maps for the Tippecanoe River near Delphi, Indiana

    Science.gov (United States)

    Menke, Chad D.; Bunch, Aubrey R.; Kim, Moon H.

    2013-01-01

    Digital flood-inundation maps for an 11-mile reach of the Tippecanoe River that extends from County Road W725N to State Road 18 below Oakdale Dam, Indiana (Ind.), 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/, depict estimates of the areal extent of flooding corresponding to selected water levels (stages) at USGS streamgage 03333050, Tippecanoe River near Delphi, Ind. Current conditions at the USGS streamgages in Indiana may be obtained online at http://waterdata.usgs.gov/in/nwis/current/?type=flow. In addition, the information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system (http://water.weather.gov/ahps/). The NWS forecasts flood hydrographs at many places that are often co-located at USGS streamgages. That forecasted peak-stage information, also available on the Internet, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, water-surface profiles were simulated for the stream reach by means of a hydraulic one-dimensional step-backwater model. The model was calibrated by using the most current stage-discharge relation at USGS streamgage 03333050, Tippecanoe River near Delphi, Ind., and USGS streamgage 03332605, Tippecanoe River below Oakdale Dam, Ind. The hydraulic model was then used to simulate 13 water-surface profiles for flood stages at 1-foot intervals reference to the streamgage datum and ranging from bankfull to approximately the highest recorded water level at the streamgage. The simulated water-surface profiles were then combined with a geographic information system digital elevation model (derived from Light Detection and Ranging (LiDAR) data) in order to delineate the

  11. Propagation and composition of the flood wave on the upper Mississippi River, 1993

    Science.gov (United States)

    Moody, John A.

    1995-01-01

    The flood wave on the upper Mississippi River started downstream near St. Paul, Minnesota, in June 1993. The maximum discharge propagated downstream at about 50 kilometers per day and was 5 to 7 times the mean daily discharge at streamgaging sites on the river. The propagation speed of the flood wave was influenced more by hydrologic factors such as tributary inflow and flood-plain storage than by hydraulic factors. The maximum discharge at St. Louis, Missouri (29,700 m3/s) occurred on August 1, 1993; but because of flood-plain storage resulting from levee failures and seepage through and under levees downstream, the maximum discharge at Thebes, Illinois, (27,700 m>3/s) did not occur until August 7 which was about 4 days later than normal.

  12. PROVISION OF DIKE SLOPE STABILITY FOR TERRITORY PROTECTION AGAINST GORYN RIVER FLOODS

    Directory of Open Access Journals (Sweden)

    E. Michnevich

    2013-01-01

    Full Text Available Hydrologic conditions that cause the Goryn river floods have been described in the paper. The paper considers engineering solutions pertaining to prevention of catastrophic floodings by bifurcation of maximum river flow while constructing a watershed dike and creating a non-flood polder in the flood plain. The formulas have been developed for calculation of dike slope fixing by dumped riprap when the slopes are subjected to stream impact. The paper provides an analysis of existing dependences for calculation of riprap material size in order to protect slopes against waves. The possible ways for lower cost of fixation while using  waste tyres and also while constructing  small wave-suppressing dikes reinforced by dumped riprap and shrub vegetation along the main dike have been revealed in the paper.

  13. Flood risk analysis of the Limpopo River basin through past evolution reconstruction and geomorphological approach

    Directory of Open Access Journals (Sweden)

    M. Spaliviero

    2014-02-01

    Full Text Available This research reconstructs the past evolution of the Limpopo River, a transboundary system located in south-eastern Africa, and describes its geomorphological settings through literature review and field work activities, with aim to analyse the risk of floods in the basin. Major changes have occurred since the late Jurassic – early Cretaceous period due to successive tectonic events. The paper demonstrates that the apparently abandoned drainage conformation of the palaeo-Limpopo in the upper and middle stretches of the river constitutes today preferential flood-prone areas in case of major rainfall events. An important palaeo-delta is identified in the lower Limpopo, which imposes a particular drainage pattern to the floodplain in Mozambique and influences the floods dynamics at present. The adopted method is helpful in determining flood risk in a data-scarce area showing complex fluvial dynamics, and allows identifying unsuitable locations for human settlements.

  14. Planning of technical flood retention measures in large river basins under consideration of imprecise probabilities of multivariate hydrological loads

    OpenAIRE

    Nijssen, D.; Schumann, A; Pahlow, M.; Klein, B.

    2009-01-01

    As a result of the severe floods in Europe at the turn of the millennium, the ongoing shift from safety oriented flood control towards flood risk management was accelerated. With regard to technical flood control measures it became evident that the effectiveness of flood control measures depends on many different factors, which cannot be considered with single events used as design floods for planning. The multivariate characteristics of the hydrological loads have to be considered to evaluat...

  15. Preliminary assessment of metal toxicity in the middle Tisza river (Hungary) flood plain

    Energy Technology Data Exchange (ETDEWEB)

    Black, M.C.; Williams, P.L. [Dept. of Environmental Health Science, Univ. of Georgia, Athens, GA (United States)

    2001-07-01

    Cyanide and heavy metals were accidentally released from a mine waste lagoon in Romania into tributaries ultimately draining into the Tisza River. Within two months of the cyanide accident two subsequent heavy metal waste spills further contaminated the Tisza River, followed by severe spring flooding, which potentially spread the contamination to soils adjacent to the river. Flood plain soils and shoreline sediments were sampled from two locations on the middle Tisza River and a reference site to conduct a preliminary assessment of metal content and toxicity. Ten-day sediment toxicity tests were conducted with the amphipod, Hyalella azteca and 24 h soil toxicity tests were conducted with the nematode (Caenorhabditis elegans). High concentrations of cadmium, copper, zinc, lead and arsenic were detected in soil and sediment samples. However, no mortality was observed in Hyalella exposed to Tisza River sediments and only up to 27% mortality of C. elegans was observed in flood plain soils. Low mortalities are attributed to reduced metal bioavailability caused by high soil cation exchange capacities and possible interactions with sediment organic matter or sulfides. Future studies should focus on factors that alter metal bioavailability and their relationship to potential toxicity of organisms exposed to Tisza River sediments and flood plain soils. (orig.)

  16. Flood Control, Mississippi River, La Crosse, Wisconsin.

    Science.gov (United States)

    1975-10-01

    House, 410 Cass St. Random ashlar stone house c. 1868 with 3-story tower. Italian Villa style with Gothic elements. Anderson, Mons, Mercantile Bldg., 2nd...National Historic Landmark which was the home of the famous author, Hamlin Garland, from 1893 to 1915. Described in his novel , A Son of the Middle Border...the twentieth century. Gaspard HOuse, Cass at 7th. Story and a half frame cottage in Gothic Revival c. 1859. Some alterations on facade. W. W. Crosby

  17. Special Flood Hazard Evaluation Report, Maumee River, Defiance and Paulding Counties, Ohio

    Science.gov (United States)

    1988-01-01

    into the Flood Flow Frequency Analysis (FFFA) computer program (Reference 3) to determine the discharge-frequency relationship for the Maumee River...although the flood may occur in any year. It is based on statistical analysis of streamflow records available for the watershed and analysis of rainfall...C) K) K4 10 ERFODBUDR .S ryEgne itit ufI N - FODA ONAYSEIA LO AADEAUTO 6 ? -F -C )I= ~ - %E )tvXJ. AE LO LVTO MAMERVE CROS SECIONLOCAION DEFINCEAND

  18. Runoff Simulation of Three Gorges Area in the Upper Yangtze River during 1998 Flood Season

    Institute of Scientific and Technical Information of China (English)

    LIN Jian; Gabor BALINT; Balazs GAUZER

    2005-01-01

    The contribution of areal precipitation of the catchment from Cuntan to Yichang (Three Gorges area)to eight flood peaks of the Upper Yangtze River (the upper reaches of the Yangtze River) is diagnosed for 1998 flood season. A rainfall-runoff model is employed to simulate runoffs of this catchment. Comparison of observed and simulated runoffs shows that the rainfall-runoff model has a good capability to simulate the runoff over a large-scale river and the results describe the eight flood peaks very well Forecast results are closely associated with the sensitivity of the model to rainfall and the calibration processes. Other reasons leading to simulation errors are further discussed.

  19. Future flood risk estimates along the river Rhine

    Directory of Open Access Journals (Sweden)

    A. H. te Linde

    2011-02-01

    Full Text Available In Europe, water management is moving from flood defence to a risk management approach, which takes both the probability and the potential consequences of flooding into account. It is expected that climate change and socio-economic development will lead to an increase in flood risk in the Rhine basin. To optimize spatial planning and flood management measures, studies are needed that quantify future flood risks and estimate their uncertainties. In this paper, we estimated the current and future fluvial flood risk in 2030 for the entire Rhine basin in a scenario study. The change in value at risk is based on two land-use projections derived from a land-use model representing two different socio-economic scenarios. Potential damage was calculated by a damage model, and changes in flood probabilities were derived from two climate scenarios and hydrological modeling. We aggregated the results into seven sections along the Rhine. It was found that the annual expected damage in the Rhine basin may increase by between 54% and 230%, of which the major part (~ three-quarters can be accounted for by climate change. The highest current potential damage can be found in the Netherlands (110 billion €, compared with the second (80 billion € and third (62 billion € highest values in two areas in Germany. Results further show that the area with the highest fluvial flood risk is located in the Lower Rhine in Nordrhein-Westfalen in Germany, and not in the Netherlands, as is often perceived. This is mainly due to the higher flood protection standards in the Netherlands as compared to Germany.

  20. Regional L-Moment-Based Flood Frequency Analysis in the Upper Vistula River Basin, Poland

    Science.gov (United States)

    Rutkowska, A.; Żelazny, M.; Kohnová, S.; Łyp, M.; Banasik, K.

    2016-05-01

    The Upper Vistula River basin was divided into pooling groups with similar dimensionless frequency distributions of annual maximum river discharge. The cluster analysis and the Hosking and Wallis (HW) L-moment-based method were used to divide the set of 52 mid-sized catchments into disjoint clusters with similar morphometric, land use, and rainfall variables, and to test the homogeneity within clusters. Finally, three and four pooling groups were obtained alternatively. Two methods for identification of the regional distribution function were used, the HW method and the method of Kjeldsen and Prosdocimi based on a bivariate extension of the HW measure. Subsequently, the flood quantile estimates were calculated using the index flood method. The ordinary least squares (OLS) and the generalised least squares (GLS) regression techniques were used to relate the index flood to catchment characteristics. Predictive performance of the regression scheme for the southern part of the Upper Vistula River basin was improved by using GLS instead of OLS. The results of the study can be recommended for the estimation of flood quantiles at ungauged sites, in flood risk mapping applications, and in engineering hydrology to help design flood protection structures.

  1. Regional L-Moment-Based Flood Frequency Analysis in the Upper Vistula River Basin, Poland

    Science.gov (United States)

    Rutkowska, A.; Żelazny, M.; Kohnová, S.; Łyp, M.; Banasik, K.

    2017-02-01

    The Upper Vistula River basin was divided into pooling groups with similar dimensionless frequency distributions of annual maximum river discharge. The cluster analysis and the Hosking and Wallis (HW) L-moment-based method were used to divide the set of 52 mid-sized catchments into disjoint clusters with similar morphometric, land use, and rainfall variables, and to test the homogeneity within clusters. Finally, three and four pooling groups were obtained alternatively. Two methods for identification of the regional distribution function were used, the HW method and the method of Kjeldsen and Prosdocimi based on a bivariate extension of the HW measure. Subsequently, the flood quantile estimates were calculated using the index flood method. The ordinary least squares (OLS) and the generalised least squares (GLS) regression techniques were used to relate the index flood to catchment characteristics. Predictive performance of the regression scheme for the southern part of the Upper Vistula River basin was improved by using GLS instead of OLS. The results of the study can be recommended for the estimation of flood quantiles at ungauged sites, in flood risk mapping applications, and in engineering hydrology to help design flood protection structures.

  2. An application of water quality index to reduce the effect of flood on water quality of rivers

    Directory of Open Access Journals (Sweden)

    Mahmoodreza Nooralinejad

    2016-06-01

    Full Text Available The rivers are among the most important resources of water supplying used for drinking consumptions, agriculture, industry, etc. Creation of a regular control plan and monitoring the water quality of these resources are the most important solutions in order to reduce the pollution and promote their qualitative conditions. The changes in climatic such as low levels of rainfall, is one of the factors influencing on the quantitative level of rivers. In addition, weather pollution and reduction in the power of soil resources are very important. This paper presents an investigation to investigate on how to reduce the influences of flood water on the water quality of the rivers based on the model of water quality index. The applied methodology is descriptive-analytical, which uses SPSS software, and t-test and correlation tests are used to analyze the data. The investigation carried out on the influences of the flood water due to raining on the qualitative changes of the water of Cesar River represented that there was a significant relationship between raining, discharge and the parameters of water quality. These relations indicate that the occurrence of raining and increase in the discharge follow the increase in the water quality of the river.

  3. FLOOD RESILIENCE AND SUSTAINABLE DEVELOPMENT IN URBAN NIGERIA: INTEGRATING TRADITIONAL AND NON-STRUCTURAL METHODS OF MITIGATING AND ADAPTING TO FLOODING IN CROSS RIVER STATE, SOUTH-EASTERN NIGERIA (I

    Directory of Open Access Journals (Sweden)

    RICHARD INGWE

    2012-12-01

    Full Text Available Flood resilience and sustainable development in urban Nigeria: integrating traditional and non-structural methods of mitigating and adapting to flooding in cross river state, south-eastern Nigeria. We examined application of non-structural measures in addition to conventional structural approaches by Government Agency and community for flood management in Cross River State (Nigeria at: regional-ambit and community levels. We used focus group discussion in depth interview, and observation methods to collect datafrom primary and secondary sources. Our findings include: emphasis on structural flood control measures by government agencies contrasted to use of rudimentary non-structural approaches by communities. Conceptual frames proposed for managing disasters include: emphasizing future climate change impacts based on multiple scales (temporal, spatial and societal and emphasizing historical response to disasters without increasing the visibility of climate change. We conclude that community institutions, non-government/civil society organizations should lead public institutions in promoting flood resilience based on integrated non-structural to structural measures and show recent developments regarding civil society coalition committed towards promoting environmental governance in Nigeria. Frequent flooding associated with huge losses of lives and property in the studyareas, as in most of urban Nigeria, persuade us to recommend that strategically placed civil society be supported by donor/funding organizations to promote integrated non-structural and traditional-structural measures to achieve urban flood resilience nationwide.

  4. FLOOD RESILIENCE AND SUSTAINABLE DEVELOPMENT IN URBAN NIGERIA: INTEGRATING TRADITIONAL AND NON-STRUCTURAL METHODS OF MITIGATING AND ADAPTING TO FLOODING IN CROSS RIVER STATE, SOUTH-EASTERN NIGERIA (II

    Directory of Open Access Journals (Sweden)

    RICHARD INGWE

    2013-04-01

    Full Text Available Flood resilience and sustainable development in urban Nigeria: integrating traditional and non-structural methods of mitigating and adapting to flooding in cross river state, south-eastern Nigeria. We examined application of non-structural measures in addition to conventional structural approaches by Government Agency and community for flood management in Cross River State (Nigeria at: regional-ambit and community levels. We used focus group discussion in depth interview, and observation methods to collect data from primary and secondary sources. Our findings include: emphasis on structural flood control measures by government agencies contrasted to use of rudimentary non-structural approaches by communities. Conceptual frames proposed for managing disasters include: emphasizing future climate change impacts based on multiple scales (temporal, spatial and societal and emphasizing historical response to disasters without increasing the visibility of climate change. We conclude that community institutions, non-government/civil society organizations should lead public institutions in promoting flood resilience based on integrated non-structural to structural measures and show recent developments regarding civil society coalition committed towards promoting environmental governance in Nigeria. Frequent flooding associated with huge losses of lives and property in the study areas, as in most of urban Nigeria, persuade us to recommend that strategically placed civil society be supported by donor/funding organizations to promote integrated non-structural and traditional-structural measures to achieve urban flood resilience nationwide.

  5. Late Pleistocene outburst flooding from pluvial Lake Alvord into the Owyhee River, Oregon

    Science.gov (United States)

    Carter, Deron T.; Ely, Lisa L.; O'Connor, Jim E.; Fenton, Cassandra R.

    2006-05-01

    At least one large, late Pleistocene flood traveled into the Owyhee River as a result of a rise and subsequent outburst from pluvial Lake Alvord in southeastern Oregon. Lake Alvord breached Big Sand Gap in its eastern rim after reaching an elevation of 1292 m, releasing 11.3 km 3 of water into the adjacent Coyote Basin as it eroded the Big Sand Gap outlet channel to an elevation of about 1280 m. The outflow filled and then spilled out of Coyote Basin through two outlets at 1278 m and into Crooked Creek drainage, ultimately flowing into the Owyhee and Snake Rivers. Along Crooked Creek, the resulting flood eroded canyons, stripped bedrock surfaces, and deposited numerous boulder bars containing imbricated clasts up to 4.1 m in diameter, some of which are located over 30 m above the present-day channel. Critical depth calculations at Big Sand Gap show that maximum outflow from a 1292- to 1280-m drop in Lake Alvord was ˜ 10,000 m 3 s - 1 . Flooding became confined to a single channel approximately 40 km downstream of Big Sand Gap, where step-backwater calculations show that a much larger peak discharge of 40,000 m 3 s - 1 is required to match the highest geologic evidence of the flood in this channel. This inconsistency can be explained by (1) a single 10,000 m 3 s - 1 flood that caused at least 13 m of vertical incision in the channel (hence enlarging the channel cross-section); (2) multiple floods of 10,000 m 3 s - 1 or less, each producing some incision of the channel; or (3) an earlier flood of 40,000 m 3 s - 1 creating the highest flood deposits and crossed drainage divides observed along Crooked Creek drainage, followed by a later 10,000 m 3 s - 1 flood associated with the most recent shorelines in Alvord and Coyote Basins. Well-developed shorelines of Lake Alvord at 1280 m and in Coyote Basin at 1278 m suggest that after the initial flood, postflood overflow persisted for an extended period, connecting Alvord and Coyote Basins with the Owyhee River of the

  6. Flood inundation maps for the Wabash River at New Harmony, Indiana

    Science.gov (United States)

    Fowler, Kathleen K.

    2016-10-11

    Digital flood-inundation maps for a 3.68-mile reach of the Wabash River extending 1.77 miles upstream and 1.91 miles downstream from streamgage 03378500 at New Harmony, Indiana, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage at Wabash River at New Harmony, Ind. (station 03378500). Near-real-time stages at this streamgage may be obtained from the USGS National Water Information System at http://waterdata.usgs.gov/ or the National Weather Service (NWS) Advanced Hydrologic Prediction Service at http://water.weather.gov/ahps/, which also forecasts flood hydrographs at this site (NHRI3).Flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The hydraulic model was calibrated by using the most current stage-discharge relations at the Wabash River at New Harmony, Ind., streamgage and the documented high-water marks from the flood of April 27–28, 2013. The calibrated hydraulic model was then used to compute 17 water-surface profiles for flood stages at approximately 1-foot intervals referenced to the streamgage datum and ranging from 10.0 feet, or near bankfull, to 25.4 feet, the highest stage of the stage-discharge rating curve used in the model. 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 0.98-ft vertical accuracy and 4.9-ft horizontal resolution) to delineate the area flooded at each water level.The availability of these maps along with Internet information regarding current stage from the USGS streamgage at Wabash River at New

  7. 天然气管道穿越工程的防洪分析%Application of 2D Mathematical Model in Flood Control Evaluation of Caohe River Bridge

    Institute of Scientific and Technical Information of China (English)

    冯亚辉

    2014-01-01

    结合保定天然气管道穿越漕河建设项目,对定向钻穿越工程的防洪评价要点进行分析,并提出可行的防治与补救措施建议,为项目审批和建设提供科学依据。%Based on the project of Baoding natural gas pipeline through Caohe river , the paper ana-lyzed the flood evaluation points of direction drilling crossing engineering , and puts forward some sug-gestions of prevention and remedy measures , provides scientificbasis for project approval and con-struction.

  8. Challenges in modeling ice floods on the Ningxia-Inner Mongolia reach of the Yellow River, China

    NARCIS (Netherlands)

    Fu, C.; Popescu, I.; Wang, C.; Mynett, A.E.; Zhang, F.

    2013-01-01

    During winter the Yellow River in China is frequently subjected to ice flood disasters. Possible dike-breaking due to ice floods poses a serious threat to the part of the region located along the river, in particular the Ning-Meng reach (including Ningxia Hui and the Inner Mongolia Autonomous Region

  9. Urbanization Impacts on Flooding in the Kansas River Basin and Evaluation of Wetlands as a Mitigation Measure

    Science.gov (United States)

    This study evaluates the impacts of future land use changes on flooding in the Kansas River Basin. It also studies the impacts of wetlands on flood reduction. The study presents Hydrologic Engineering Centers-Hydrologic Modeling System (HEC-HMS) based runoff modeling and River A...

  10. Flooding ecology of voles, mice and shrews: the importance of geomorphological and vegetational heterogeneity in river floodplains

    NARCIS (Netherlands)

    Wijnhoven, S.; Velde, G. van der; Leuven, R.S.E.W.; Smits, A.J.M.

    2005-01-01

    Since voles, mice and shrews are important animals in food chains of river floodplains, there is a need for data on their spatial and temporal distribution in periodically flooded areas. During a live trapping study between two successive floods in an embanked river floodplain, the ’Afferdensche en

  11. Declining vulnerability to river floods and the global benefits of adaptation.

    Science.gov (United States)

    Jongman, Brenden; Winsemius, Hessel C; Aerts, Jeroen C J H; Coughlan de Perez, Erin; van Aalst, Maarten K; Kron, Wolfgang; Ward, Philip J

    2015-05-05

    The global impacts of river floods are substantial and rising. Effective adaptation to the increasing risks requires an in-depth understanding of the physical and socioeconomic drivers of risk. Whereas the modeling of flood hazard and exposure has improved greatly, compelling evidence on spatiotemporal patterns in vulnerability of societies around the world is still lacking. Due to this knowledge gap, the effects of vulnerability on global flood risk are not fully understood, and future projections of fatalities and losses available today are based on simplistic assumptions or do not include vulnerability. We show for the first time (to our knowledge) that trends and fluctuations in vulnerability to river floods around the world can be estimated by dynamic high-resolution modeling of flood hazard and exposure. We find that rising per-capita income coincided with a global decline in vulnerability between 1980 and 2010, which is reflected in decreasing mortality and losses as a share of the people and gross domestic product exposed to inundation. The results also demonstrate that vulnerability levels in low- and high-income countries have been converging, due to a relatively strong trend of vulnerability reduction in developing countries. Finally, we present projections of flood losses and fatalities under 100 individual scenario and model combinations, and three possible global vulnerability scenarios. The projections emphasize that materialized flood risk largely results from human behavior and that future risk increases can be largely contained using effective disaster risk reduction strategies.

  12. Efficient pan-European river flood hazard modelling through a combination of statistical and physical models

    Science.gov (United States)

    Paprotny, Dominik; Morales-Nápoles, Oswaldo; Jonkman, Sebastiaan N.

    2017-07-01

    Flood hazard is currently being researched on continental and global scales, using models of increasing complexity. In this paper we investigate a different, simplified approach, which combines statistical and physical models in place of conventional rainfall-run-off models to carry out flood mapping for Europe. A Bayesian-network-based model built in a previous study is employed to generate return-period flow rates in European rivers with a catchment area larger than 100 km2. The simulations are performed using a one-dimensional steady-state hydraulic model and the results are post-processed using Geographical Information System (GIS) software in order to derive flood zones. This approach is validated by comparison with Joint Research Centre's (JRC) pan-European map and five local flood studies from different countries. Overall, the two approaches show a similar performance in recreating flood zones of local maps. The simplified approach achieved a similar level of accuracy, while substantially reducing the computational time. The paper also presents the aggregated results on the flood hazard in Europe, including future projections. We find relatively small changes in flood hazard, i.e. an increase of flood zones area by 2-4 % by the end of the century compared to the historical scenario. However, when current flood protection standards are taken into account, the flood-prone area increases substantially in the future (28-38 % for a 100-year return period). This is because in many parts of Europe river discharge with the same return period is projected to increase in the future, thus making the protection standards insufficient.

  13. Detrital phosphorus as a proxy of flooding events in the Changjiang River Basin

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Jia [Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Qingdao 266100 (China); College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100 (China); Yao, Peng, E-mail: yaopeng@mail.ouc.edu.cn [Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Qingdao 266100 (China); Qingdao Collaborative Innovation Center of Marine Science and Technology, Qingdao 266100 (China); Institute of Marine Organic Geochemistry, Ocean University of China, Qingdao 266100 (China); Bianchi, Thomas S. [Department of Geological Sciences, University of Florida, Gainesville, FL 32611-2120 (United States); Li, Dong; Zhao, Bin; Xu, Bochao [Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Qingdao 266100 (China); College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100 (China); Yu, Zhigang [Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Qingdao 266100 (China); Institute of Marine Organic Geochemistry, Ocean University of China, Qingdao 266100 (China)

    2015-06-01

    In this study, sediment grain size (MGS), specific surface area (SSA), total organic carbon (TOC) contents, C/N molar ratios, stable carbon isotope, and P species in a sediment core, collected from the East China Sea (ECS) inner-shelf were measured to explore the applicability of detrital phosphorus (De-P) as a potential indicator of past flooding events in the Changjiang River Basin (CRB). In particular, we examined the linkages between the evolution of floods with regional climate changes and anthropogenic activities in the CRB. Peaks of De-P concentrations in sediments corresponded well with the worst flooding events of the CRB over the past two centuries (e.g., 1850s, 1860s, 1900s, 1920s, 1950s, 1980s, and 2000s). Moreover, De-P also corresponded well with the extreme hypoxic events in 1981 and 1998 in the Changjiang Estuary as indicated by Mo/Al ratios, indicating potential linkages between De-P as a flooding proxy to flood-induced hypoxia events in this region. In addition, a robust relationship was found among De-P, the floods in 1950s, 1980s, and 2000s of the CRB, the intensive El Niño-Southern Oscillation (ENSO), the abnormally weak East Asian Summer Monsoon (EASM) and the warm phase of Pacific Decadal Oscillation (PDO), suggesting that De-P also provided insights to linkages between regional climate change and flooding events in this region. - Highlights: • De-P was used to track past floods in the Changjiang River Basin (CRB). • De-P may serve as a proxy for flood-induced hypoxia events in the Changjiang Estuary. • De-P may be a proxy for examining linkages between floods and climatic drivers.

  14. Flood-inundation maps for the St. Joseph River at Elkhart, Indiana

    Science.gov (United States)

    Martin, Zachary W.

    2017-02-01

    Digital flood-inundation maps for a 6.6-mile reach of the St. Joseph River at Elkhart, Indiana, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at https://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage 04101000, St. Joseph River at Elkhart, Ind. Real-time stages at this streamgage may be obtained on the Internet from the USGS National Water Information System at https://waterdata.usgs.gov/nwis or the National Weather Service (NWS) Advanced Hydrologic Prediction Service at http:/water.weather.gov/ahps/, which also forecasts flood hydrographs at this site (NWS site EKMI3).Flood profiles were computed for the stream reach by means of a one-dimensional, step-backwater hydraulic modeling software developed by the U.S. Army Corps of Engineers. The hydraulic model was calibrated using the current stage-discharge rating at the USGS streamgage 04101000, St. Joseph River at Elkhart, Ind., and the documented high-water marks from the flood of March 1982. The hydraulic model was then used to compute six water-surface profiles for flood stages at 1-foot (ft) intervals referenced to the streamgage datum ranging from 23.0 ft (the NWS “action stage”) to 28.0 ft, which is the highest stage interval of the current USGS stage-discharge rating curve and 1 ft higher than the NWS “major flood stage.” 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 0.49-ft root mean squared error and 4.9-ft horizontal resolution, resampled to a 10-ft grid) to delineate the area flooded at each stage.The availability of these maps, along with Internet information

  15. Determination of bioavailable contaminants in the lower Missouri River following the flood of 1993

    Science.gov (United States)

    Petty, J.D.; Poulton, B.C.; Charbonneau, C.S.; Huckins, J.N.; Jones, S.B.; Cameron, J.T.; Prest, H.F.

    1998-01-01

    The semipermeable membrane device (SPMD) technology was employed to determine the presence of bioavailable organochlorine pesticides (OCs), polychlorinated biphenyls (PCBs), and polyaromatic hydrocarbons (PAHs)in the water of the main stem of the lower Missouri River and three of its tributaries. The SPMDs were deployed in 1994 following the extensive flood of 1993. Specifically, the SPMDs were deployed for 28 days at Wilson State Park, IA; Nebraska City, NE; Parkville, MO; the Kansas River in Kansas City, KS; Napoleon, MO; the Grand River; Glasgow, MO; the Missouri River upstream from the confluence of the Gasconade River; the Gasconade River, and Hermann, MO. Contaminant residues were found at all sites and at higher concentrations than found in the earlier pre-flood sampling. For example, in the present study, dieldrin was found to range from a low of 110 ng/sample in the Gasconade River to a high of 2000 ng/sample at Glasgow, while in the pre- flood sampling, dieldrin ranged from a low of 64 ng/sample at Sioux City to a high of 800 ng/sample at Glasgow. In contrast to the 1992 sampling, residues of PCBs were found at all 1994 sampling sites except the Gasconade River. Samples from Wilson State Park and the Grand River had 3100 and 2700 ng of PCBs/sample, respectively. These two concentrations are about an order of magnitude higher than the older sites and are likely indicative of point source inputs. PAHs were present in SPMD samples from three sites near Kansas City. The contaminant residues sequestered by the SPMDs represent an estimation of the bioavailable (via respiration) contaminants present in the main stem of the lower Missouri River and three of its major tributaries following an extensive flood event.The semipermeable membrane device (SPMD) technology was employed to determine the presence of bioavailable organochlorine pesticides, polychlorinated biphenyls, and polyaromatic hydrocarbons in the water of the main stem of the lower Missouri River and

  16. Use of a Smartphone for Collecting Data on River Discharge and Communication of Flood Risk.

    Science.gov (United States)

    Pena-Haro, S.; Lüthi, B.; Philippe, T.

    2015-12-01

    Although many developed countries have well-established systems for river monitoring and flood early warning systems, the population affected in developing countries by flood events is unsettled. Even more, future climate development is likely to increase the intensity and frequency of extreme weather events and therefore bigger impacts on the population can be expected.There are different types of flood forecasting systems, some are based on hydrologic models fed with rainfall predictions and observed river levels. Flood hazard maps are also used to increase preparedness in case of an extreme event, however these maps are static since they do not incorporate daily changing conditions on river stages. However, and especially in developing countries, data on river stages are scarce. Some of the reasons are that traditional fixed monitoring systems do not scale in terms of costs, repair is difficult as well as operation and maintenance, in addition vandalism poses additional challenges. Therefore there is a need of cheaper and easy-to-use systems for collecting information on river stage and discharge. We have developed a mobile device application for determining the water stage and discharge of open-channels (e.g. rivers, artificial channels, irrigation furrows). Via image processing the water level and surface velocity are measured, combining this information with priori knowledge on the channel geometry the discharge is estimated. River stage and discharge measurement via smart phones provides a non-intrusive, accurate and cost-effective monitoring method. No permanent installations, which can be flooded away, are needed. The only requirement is that the field of view contains two reference markers with known scale and with known position relative to the channel geometry, therefore operation and maintenance costs are very low. The other advantage of using smartphones, is that the data collected can be immediately sent via SMS to a central database. This

  17. High-fidelity numerical modeling of the Upper Mississippi River under extreme flood condition

    Science.gov (United States)

    Khosronejad, Ali; Le, Trung; DeWall, Petra; Bartelt, Nicole; Woldeamlak, Solomon; Yang, Xiaolei; Sotiropoulos, Fotis

    2016-12-01

    We present data-driven numerical simulations of extreme flooding in a large-scale river coupling coherent-structure resolving hydrodynamics with bed morphodynamics under live-bed conditions. The study area is a ∼ 3.2 km long and ∼ 300 m wide reach of the Upper Mississippi River, near Minneapolis MN, which contains several natural islands and man-made hydraulic structures. We employ the large-eddy simulation (LES) and bed-morphodynamic modules of the Virtual Flow Simulator (VFS-Rivers) model, a recently developed in-house code, to investigate the flow and bed evolution of the river during a 100-year flood event. The coupling of the two modules is carried out via a fluid-structure interaction approach using a nested domain approach to enhance the resolution of bridge scour predictions. We integrate data from airborne Light Detection and Ranging (LiDAR), sub-aqueous sonar apparatus on-board a boat and in-situ laser scanners to construct a digital elevation model of the river bathymetry and surrounding flood plain, including islands and bridge piers. A field campaign under base-flow condition is also carried out to collect mean flow measurements via Acoustic Doppler Current Profiler (ADCP) to validate the hydrodynamic module of the VFS-Rivers model. Our simulation results for the bed evolution of the river under the 100-year flood reveal complex sediment transport dynamics near the bridge piers consisting of both scour and refilling events due to the continuous passage of sand dunes. We find that the scour depth near the bridge piers can reach to a maximum of ∼ 9 m. The data-driven simulation strategy we present in this work exemplifies a practical simulation-based-engineering-approach to investigate the resilience of infrastructures to extreme flood events in intricate field-scale riverine systems.

  18. The Impact of Climate Change on the Duration and Division of Flood Season in the Fenhe River Basin, China

    Directory of Open Access Journals (Sweden)

    Hejia Wang

    2016-03-01

    Full Text Available This study analyzes the duration and division of the flood season in the Fenhe River Basin over the period of 1957–2014 based on daily precipitation data collected from 14 meteorological stations. The Mann–Kendall detection, the multiscale moving t-test, and the Fisher optimal partition methods are used to evaluate the impact of climate change on flood season duration and division. The results show that the duration of the flood season has extended in 1975–2014 compared to that in 1957–1974. Specifically, the onset date of the flood season has advanced 15 days, whereas the retreat date of the flood season remains almost the same. The flood season of the Fenhe River Basin can be divided into three stages, and the variations in the onset and retreat dates of each stage are also examined. Corresponding measures are also proposed to better utilize the flood resources to adapt to the flood season variations.

  19. Mechanisms of vegetation removal by floods on bars of a heavily managed gravel bed river (The Isere River, France)

    Science.gov (United States)

    Jourdain, Camille; Belleudy, Philippe; Tal, Michal; Malavoi, Jean-René

    2016-04-01

    In natural alpine gravel bed rivers, floods and their associated bedload transport maintain channels active and free of mature woody vegetation. In managed rivers, where flood regime and sediment supply have been modified by hydroelectric infrastructures and sediment mining, river beds tend to stabilize. As a result, in the recent past, mature vegetation has established on gravel bars of many gravel bed rivers worldwide. This established vegetation increases the risk of flooding by decreasing flow velocity and increasing water levels. In addition, the associated reduction in availability of pioneer habitats characteristic of these environments typically degrades biodiversity. Managing hydrology in a way that would limit vegetation establishment on bars presents an interesting management option. In this context, our study aims at understanding the impacts of floods of varying magnitude on vegetation removal, and identifying and quantifying the underlying mechanisms. Our study site is the Isère River, a heavily managed gravel bed river flowing in the western part of the French Alps. We studied the impact of floods on sediment transport and vegetation survival at the bar scale through field monitoring from 2014 to 2015, focusing on young salicaceous vegetation (chains, and topographic surveys. Hourly water discharge was obtained from the national gauging network. The hydraulics of monitored floods was characterized using a combination of field measurements and 2D hydraulic modeling: water levels were measured with pressure sensors and Large Scale Particle Velocimetry was used to measure flow velocities. These data were used to calibrate 2D hydrodynamic model using TELEMAC2D. At the reach scale, removal of mature vegetation was assed using a series of historical aerial photographs between 2001 and 2015. Our monitoring period covered a series of floods with recurrence intervals of 2 to 4 times per year, as well as one large flood with a 10 year return period. Only the

  20. 75 FR 18238 - United States Section; Final Environmental Impact Statement, Flood Control Improvements and...

    Science.gov (United States)

    2010-04-09

    ..., Flood Control Improvements and Partial Levee Relocation, United States Section, International Boundary and Water Commission (USIBWC) Presidio Flood Control Project (FCP), Presidio, TX AGENCY: United States... potential consequences of each action alternative in reference to flood control improvements. Following...

  1. Global river flood hazard maps: hydraulic modelling methods and appropriate uses

    Science.gov (United States)

    Townend, Samuel; Smith, Helen; Molloy, James

    2014-05-01

    Flood hazard is not well understood or documented in many parts of the world. Consequently, the (re-)insurance sector now needs to better understand where the potential for considerable river flooding aligns with significant exposure. For example, international manufacturing companies are often attracted to countries with emerging economies, meaning that events such as the 2011 Thailand floods have resulted in many multinational businesses with assets in these regions incurring large, unexpected losses. This contribution addresses and critically evaluates the hydraulic methods employed to develop a consistent global scale set of river flood hazard maps, used to fill the knowledge gap outlined above. The basis of the modelling approach is an innovative, bespoke 1D/2D hydraulic model (RFlow) which has been used to model a global river network of over 5.3 million kilometres. Estimated flood peaks at each of these model nodes are determined using an empirically based rainfall-runoff approach linking design rainfall to design river flood magnitudes. The hydraulic model is used to determine extents and depths of floodplain inundation following river bank overflow. From this, deterministic flood hazard maps are calculated for several design return periods between 20-years and 1,500-years. Firstly, we will discuss the rationale behind the appropriate hydraulic modelling methods and inputs chosen to produce a consistent global scaled river flood hazard map. This will highlight how a model designed to work with global datasets can be more favourable for hydraulic modelling at the global scale and why using innovative techniques customised for broad scale use are preferable to modifying existing hydraulic models. Similarly, the advantages and disadvantages of both 1D and 2D modelling will be explored and balanced against the time, computer and human resources available, particularly when using a Digital Surface Model at 30m resolution. Finally, we will suggest some

  2. Analysis on the Utilization of Flood Resource of Daqinghe River Basin%大清河系洪水资源化利用初探

    Institute of Scientific and Technical Information of China (English)

    徐丽娟; 郝娜

    2013-01-01

    On the basis of present situation of Daqinghe flood and drought in coexist and water resources shortage, change the concept of floods prevent by water control, the authors puts forward the utilization of flood resource. Through the flood analysis, discusses the way and direction of river flood resources utilization.%  基于大清河系内洪水与干旱并存、水资源紧缺的现状,转变治水理念,提出洪水资源化利用。针对河系洪水和防洪体系特点,通过对几次河系洪水的分析,探讨了河系洪水资源化利用的方向和途径。

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

    Directory of Open Access Journals (Sweden)

    MIHAI VALENTIN HERBEI

    2012-11-01

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

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

    Science.gov (United States)

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

    2017-04-01

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

  5. Influence of floods on natural riparian forests along the Ergis River,west China

    Institute of Scientific and Technical Information of China (English)

    CHENG Kewu; ZANG Runguo; ZHOU Xiaofang; ZHANG Weiyin; BAI Zhiqiang

    2007-01-01

    The riparian forests along the Ergis River,west China,composed mainly of Salicaceae species,play an important role in eco-environment protection and sustainable development of local agriculture,stockbreeding,and social economy of the northern desert region of Xinjiang Uygur Autonomous Region.The study of the influence of floods on the natural riparian forests is imperative for the understanding of the successional process and the acceleration of conservation and restoration of forests.By investigating the relationship between floods and dispersal of seeds,sprouting,natural regeneration,the structure of the forests,and their current distribution,we conclude that:1) the ripening and dispersal periods of Salicaceae species seeds overlap largely with flood occurrence periods,and the sprouting and natural regeneration of seeds depend greatly on flood events;2) floods supply soil water and increase groundwater level of riparian land through flood irrigation and horizontal infiltration to maintain the normal growth of the riparian forests;3) floods have a decisive influence on the structure,composition,and distribution pattern of riparian forests,and any disturbance in the water flow has a profound effect on these characteristics.Given these facts,some management measures for conservation and restoration of the riparian forests are proposed,including the establishment of riparian forest buffer belt,bank stabilization measures,and maintenance of flood protection.

  6. Historical flash floods retromodelling in the Ondara River in Tàrrega (NE Iberian Peninsula

    Directory of Open Access Journals (Sweden)

    J. C. Balasch

    2011-12-01

    Full Text Available Flash floods in the Ondara River have caused many fatalities and damages in the town of Tàrrega in the last 400 yr. Unfortunately, no flow records are available.

    However, floods can sometimes be reconstructed thanks to available historical information: limnimarks, written accounts and archaeological surveys. Indeed, from these data and using the retromodelling method on three different scenarios to take into account morphology changes, the peak flows of the seven greatest floods occurred in Tàrrega since the 17th century were estimated.

    The results showed that the heaviest flood's specific peak flow (10.7 m3 s−1 km−2 ranks among the highest ever modelled or measured in similar-sized catchments in the Western Mediterranean region. The results pointed out, as well, that the changes in channel's morphology (mainly, the disappearance of a mediaeval bridge under sediment caused by one of the floods increased the hydraulic capacity of a crucial cross-section. All this resulted in modest floods invading the town less often, but with much faster and, thus, more destructive flows.

    A preliminary estimation of the results' uncertainty was 4% for great floods and 18% for modest floods.

    The reconstructed peak flows will be introduced in a database for a future use in climatic and hydrological studies.

  7. Hydraulic Mining, Extreme Floods, and the Geomorphic Context of the Trinity River, CA

    Science.gov (United States)

    Krause, A.

    2012-12-01

    The geomorphology of modern Trinity River is the product of remarkable human impacts to the flow and sediment regimes. Virtually nothing is known about the river prior to the first discovery of gold in 1848. The Trinity River experienced 110 years of hydraulic mining from 1860 to 1970, a time period nearly four time as long as hydraulic mining in the Sierra Nevada Mountains. Hydraulic mining produced vast amounts of debris that aggraded unconfined valleys of the Trinity River creating sediment wedges up to 4 meters high and 20 kilometers long. Subsequent dredger gold mining dug though the valley alluvium to the bedrock interface, mixing the sediment profile and creating large tailings piles that artificially constrain the valley width. A series of large storms in the mid 20th century reworked these mining sediments, creating the modern terraces and large hydraulic controls that persist today. Subsequent flow regulation diverted up to 90 percent of the basin runoff out of the Trinity River and virtually eliminated floods, causing riparian encroachment, channel narrowing, and a largely static channel. Established in 2000, the Trinity River Restoration Program uses a process-based restoration strategy to create a dynamic channel capable of creating and maintaining sufficient salmonid habitat to meet fish population targets. The associated restoration management actions include: flow releases, coarse sediment augmentation, mechanical channel rehabilitation, and watershed restoration. Full implementation of high flow releases to promote channel dynamism began in 2005. In May 2011, a release of 11,000 cfs was conducted for river restoration purposes. The 11,000 cfs peak magnitude release is the maximum authorized for restoration purposes, the largest release in since 1974, and the third largest release since flow regulation began in November 1960. The release caused scour and deposition, creating gravel bars in several locations. The location and magnitude of scour and

  8. Maximising the usefulness of flood risk assessment for the River Vistula in Warsaw

    Science.gov (United States)

    Kiczko, A.; Romanowicz, R. J.; Osuch, M.; Karamuz, E.

    2013-12-01

    extent and flow values to be derived, thus giving a cumulative assessment of flood risk. The methods are illustrated using the Warsaw reach of the River Vistula as a case study. The results indicate that deterministic and stochastic flood inundation maps cannot be quantitatively compared. We show that the proposed simplified approach to flood risk assessment can be applied even when breaching of the embankment occurs, with the condition that the flooded area is small enough to be filled rapidly.

  9. Assessing sedimentation issues within aging of flood-control reservoirs

    Science.gov (United States)

    Flood control reservoirs designed and built by federal agencies have been extremely effective in reducing the ravages of floods nationwide. Yet some structures are being removed for a variety of reasons, while other structures are aging rapidly and require either rehabilitation or decommissioning. ...

  10. Intelligent Real-Time Reservoir Operation for Flood Control

    Science.gov (United States)

    Chang, L.; Hsu, H.

    2008-12-01

    Real-time flood control of a multi-purpose reservoir should consider decreasing the flood peak stage downstream and storing floodwaters for future usage during typhoon seasons. It is a continuous and instant decision-making process based on relevant operating rules, policy and water laws, in addition the immediate rainfall and the hydrology information; however, it is difficult to learn the intelligent experience from the elder operators. The main purpose of this study is to establish the automatic reservoir flood control model to achieve the goal of a reservoir operation during flood periods. In this study, we propose an intelligent reservoir operating methodology for real-time flood control. First, the genetic algorithm is used to search the optimal solutions, which can be considered as extracting the knowledge of reservoir operation strategies. Then, the adaptive network-based fuzzy inference system (ANFIS), which uses a hybrid learning procedure for extracting knowledge in the form of fuzzy if-then rules, is used to learn the input-output patterns and then to estimate the optimal flood operation. The Shihmen reservoir in Northern Taiwan was used as a case study, where its 26 typhoon events are investigated by the proposed method. The results demonstrate that the proposed control model can perform much better than the original reservoir operator in 26 flood events and effectively achieve decreasing peak flood stage downstream and storing floodwaters for future usage.

  11. Flood projections within the Niger River Basin under future land use and climate change.

    Science.gov (United States)

    Aich, Valentin; Liersch, Stefan; Vetter, Tobias; Fournet, Samuel; Andersson, Jafet C M; Calmanti, Sandro; van Weert, Frank H A; Hattermann, Fred F; Paton, Eva N

    2016-08-15

    This study assesses future flood risk in the Niger River Basin (NRB), for the first time considering the simultaneous effects of both projected climate change and land use changes. For this purpose, an ecohydrological process-based model (SWIM) was set up and validated for past climate and land use dynamics of the entire NRB. Model runs for future flood risks were conducted with an ensemble of 18 climate models, 13 of them dynamically downscaled from the CORDEX Africa project and five statistically downscaled Earth System Models. Two climate and two land use change scenarios were used to cover a broad range of potential developments in the region. Two flood indicators (annual 90th percentile and the 20-year return flood) were used to assess the future flood risk for the Upper, Middle and Lower Niger as well as the Benue. The modeling results generally show increases of flood magnitudes when comparing a scenario period in the near future (2021-2050) with a base period (1976-2005). Land use effects are more uncertain, but trends and relative changes for the different catchments of the NRB seem robust. The dry areas of the Sahelian and Sudanian regions of the basin show a particularly high sensitivity to climatic and land use changes, with an alarming increase of flood magnitudes in parts. A scenario with continuing transformation of natural vegetation into agricultural land and urbanization intensifies the flood risk in all parts of the NRB, while a "regreening" scenario can reduce flood magnitudes to some extent. Yet, land use change effects were smaller when compared to the effects of climate change. In the face of an already existing adaptation deficit to catastrophic flooding in the region, the authors argue for a mix of adaptation and mitigation efforts in order to reduce the flood risk in the NRB.

  12. Invasive riparian vegetation response to flow regimes and flood pulses in a braided river floodplain.

    Science.gov (United States)

    Caruso, Brian S; Pithie, Callum; Edmondson, Laura

    2013-08-15

    This study evaluated flow regimes and flood pulse characteristics, and their influences on invasive riparian vegetation, in a free-flowing braided river in the Southern Alps, South Island, New Zealand. A 46-year gauged flow record was used to evaluate 67 flow metrics for the Ahuriri River, and five sets of colour aerial photographs over 20 years (1991-2011) were analysed to quantify temporal and spatial changes in vegetation (crack willow, Russell lupin, and grassland). The correlation between flow metrics and vegetation class cover for each aerial photo interval was analysed, and multiple regression models were developed. Significant changes in different invasive vegetation classes were found, including cover, number and sizes of patches, and distances from patches to primary channels. In addition to infrequent large floods, specific characteristics of small floods, high flows, low/baseflows, and extreme low flows had influences on different vegetation classes. Key metrics that appear to drive changes in cover and provide a useful multiple regression model include the largest flood peak, frequency of floods, and the time since the last flood for each air photo interval. Up to 25% of invasive vegetation cover was removed and bare substrate increased after the largest flood on record (approximately 50-year flood), and the amount of vegetation cover is highly variable over time and space. Within approximately six years, however, the proportion of vegetation recovered to pre-flood levels. The study reach appears to demonstrate the "shifting-mosaic steady state" conceptual model of riverine floodplains, where the total proportion of substrate, vegetation and water remain relatively constant over long time periods.

  13. Flood characteristics for the Nisqually River and susceptibility of Sunshine Point and Longmire facilities to flooding in Mount Rainier National Park, Washington

    Science.gov (United States)

    Nelson, L.M.

    1987-01-01

    Inundation from 25-, 50-, 100-, and 500-year floods at Sunshine Point and Longmire facilities and the Longmire visitors ' center and ranger station generally is not a serious hazard as long as the existing dikes and banks of the Nisqually River and Tahoma Creek remain intact and flood capacities of the channels are maintained. However, average water velocities during floods are high (as much as 23 ft/sec) and the channel, banks, and some dikes are composed of unstable materials. Sunshine Point campground is particularly susceptible to flooding and damage from Tahoma Creek, and to a lesser extent from the Nisqually River, if large amounts of debris or rock material accumulate in the channels and change the flood elevation or courses of either stream. At Longmire flood inundation or damage from the Nisqually River is much less, but flooding is still possible. There, high ridges upstream protect the several park facilities from the river, but accumulations of debris or rock in the channel could cause flooding from overtopping of dikes or riverbanks. Glacial outburst floods are a matter of serious concern at both Sunshine Point campground and Longmire. Glacial outbursts can and have produced very large flood discharges and transported large quantities of debris and rock materials. Although none have been known to transport these materials from Tahoma Glacier as far as Sunshine Point campground, one in 1955 from Nisqually Glacier (estimated at 70,000 cu ft/sec near the glacier) did appreciably increase the magnitude of the water discharge at Longmire. For safety, campers and visitors need to be advised about the potential flood hazards at both facilities. (Author 's abstract)

  14. Flood-inundation maps for the White River at Indianapolis, Indiana, 2014

    Science.gov (United States)

    Nystrom, Elizabeth A.

    2015-01-01

    Digital flood-inundation maps for a 6.4-mile reach of the White River in Indianapolis, Indiana, from 0.3 miles upstream of Michigan Street to the Harding Street Generating Station dam (at the confluence with Lick Creek), were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage on the White River at Indianapolis, Ind. (station number 03353000). 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 athttp://water.weather.gov/ahps/, which also forecasts flood hydrographs at this site.

  15. Representative rainfall thresholds for flash floods in the Cali river watershed, Colombia

    Directory of Open Access Journals (Sweden)

    A. D. Ávila

    2015-06-01

    Full Text Available In the 21st century, societies face a significant increase in the number of extreme hydrometeorological events associated with climate variability (CV and/or climate change (CC. Research has recently focused on establishing adaptation and mitigation measures to counteract the effects of CV and CC, especially those associated with precipitation, such as flash floods and flooding. In this study, 27 floods, listed in the historical database of natural disasters (DesInventar, occurring between 1980 and 2012, were analyzed. Using the daily hydrometeorological data, representative rainfall thresholds were defined to predict flash floods in the hydrographic basin of the Cali River, Colombia. Antecedent rainfall (AR, or short-term rain (1, 3, 5 and 7 days, and accumulated antecedent rainfall (AAR, or long-term rain (5, 7, 10, 15, 20, 25, 30, 60 and 90 days, levels were defined. The analysis showed that the greatest determinant for the occurrence of floods is AAR, with thresholds greater than 73, 95, 124, 170, 218 and 273 mm, for 5, 7, 10, 15, 20 and 25 days, respectively. Additionally, the data showed that, historically, the greatest number of flash floods (81.7 % occurred in the Cali River basin in the months of April, May, and June.

  16. Analysis of storm tracks associated with flood events across the Paraguay River Basin

    Science.gov (United States)

    Santos, Marcus; Moura, Leonardo; Lima, Carlos; Mediero, Luis

    2017-04-01

    The hydrological time series of the Paraguay River Basin located in the Pantanal region of Brazil exhibits a complex and interesting behavior. Previous studies identified monotonic trends, multiple step changes and strong seasonality in flows and rainfall data, imposing therefore major challenges in the water resources and flood risk management in the region. The attribution of such changes is thus of particular interest, and in this work we analyze storm tracks across the Paraguay River Basin in order to better understand moisture sources and identify large scale climate patterns associated with the largest flood events in the basin. The storm path traced by virtual particles and the moisture gains and losses along such paths are obtained using the HYSPLIT Lagrangian model and the NCEP/NCAR reanalysis data for the period 1970-2016. A K-means clustering algorithm is employed to find patterns in the storm track data and for each cluster we obtain the distribution and statistics of the associated flood events. Preliminary results show that the source regions of moisture, namely tropical North Atlantic, South Atlantic and Amazon, play a significant role on the features of flood events, particularly in the magnitude of these events. Major floods seem to be related to a large influx of moisture coming from the Amazon region. We also observe that base flow and internal dynamics of the catchment play a minor role on the streamflow variability. These findings are a new step towards a better understanding and improvement of the flood risk management in the region.

  17. Flood-inundation maps for the St. Marys River at Decatur, Indiana

    Science.gov (United States)

    Strauch, Kellan R.

    2015-08-24

    Digital flood-inundation maps for an 8.9-mile reach of the St. Marys River at Decatur, Indiana, were developed by the U.S. Geological Survey (USGS), in cooperation with the Indiana Office of Community and Rural Affairs. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site (http://water.usgs.gov/osw/flood_inundation/), depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) of the St. Marys River at Decatur (USGS station number 04181500). The maps are useful for estimating near-real-time areas of inundation by referencing concurrent USGS streamgage information at http://waterdata.usgs.gov/. In addition, the streamgage information was provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service flood warning system (http:/water.weather.gov/ahps/). NWS-forecasted peak-stage information may be used in conjunction with the maps developed during this study to show predicted areas of flood inundation.

  18. Flood-inundation maps for the Big Blue River at Shelbyville, Indiana

    Science.gov (United States)

    Fowler, Kathleen K.

    2017-02-13

    Digital flood-inundation maps for a 4.1-mile reach of the Big Blue River at Shelbyville, Indiana, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The floodinundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at https://water. usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage on the Big Blue River at Shelbyville, Ind. (station number 03361500). Near-real-time stages at this streamgage may be obtained from the USGS National Water Information System at https://waterdata. usgs.gov/ or the National Weather Service (NWS) Advanced Hydrologic Prediction Service at https://water.weather.gov/ ahps/, which also forecasts flood hydrographs at this site (SBVI3). Flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The hydraulic model was calibrated by using the most current stage-discharge relation at the Big Blue River at Shelbyville, Ind., streamgage. The calibrated hydraulic model was then used to compute 12 water-surface profiles for flood stages referenced to the streamgage datum and ranging from 9.0 feet, or near bankfull, to 19.4 feet, the highest stage of the current stage-discharge rating curve. 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 0.98-foot vertical accuracy and 4.9-foot horizontal resolution) to delineate the area flooded at each water level. The availability of these maps, along with Internet information regarding current stage from the USGS streamgage at the Big Blue River at Shelbyville, Ind., and forecasted stream stages from the NWS, will provide emergency management personnel and residents with information that is critical for flood response

  19. Flood-inundation maps for the Wabash River at Memorial Bridge at Vincennes, Indiana

    Science.gov (United States)

    Fowler, Kathleen K.; Menke, Chad D.

    2017-08-23

    Digital flood-inundation maps for a 10.2-mile reach of the Wabash River from Sevenmile Island to 3.7 mile downstream of Memorial Bridge (officially known as Lincoln Memorial Bridge) at Vincennes, Indiana, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/ depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at USGS streamgage 03343010, Wabash River at Memorial Bridge at Vincennes, Ind. 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 at http:/water.weather.gov/ahps/, which also forecasts flood hydrographs at this site.For this study, flood profiles were computed for the Wabash River reach by means of a one-dimensional stepbackwater model. The hydraulic model was calibrated by using the most current stage-discharge relations at USGS streamgage 03343010, Wabash River at Memorial Bridge at Vincennes, Ind., and preliminary high-water marks from a high-water event on April 27, 2013. The calibrated hydraulic model was then used to determine 19 water-surface profiles for flood stages at 1-foot intervals referenced to the streamgage datum and ranging from 10 feet (ft) or near bankfull to 28 ft, the highest stage of the current stage-discharge rating curve. The simulated water-surface profiles were then combined with a Geographic Information System (GIS) digital elevation model (DEM, derived from Light Detection and Ranging [lidar] data having a 0.98-ft vertical accuracy and 4.9-ft horizontal resolution) in order to delineate the area flooded at each water level.The availability of these maps—along with Internet information

  20. Application of Physical Planning Strategies to Flood Control in Maiduguri, Borno State, Nigeria

    Directory of Open Access Journals (Sweden)

    H.B. Bwala

    2015-07-01

    Full Text Available Flood is a global natural disaster that has hugely cost the world in human and property loss with Nigeria having her own share of the menace at different times, the greatest of which occurred in 2012 when the country lost up to 363 people and 1.4% of her GDP to flood. This study which aims at providing permanent solutions to flooding and its attendant’s effects in the study area was carried out in the six wards of Maiduguri metropolis most vulnerable to flood. Data obtained in respect of socio-economic characteristics indicated most inhabitants of the areas are in low income cadre earning living from farming, petty trading and artisanship with 0nly 17.6% as civil servants. Findings revealed that the area which though according to master plan, was originally designated for farming has been fully built up. About 62% of inhabitants had hitherto experienced flood, yet are still occupying the area for various reasons ranging from cheapness of land and rent, poor finance, family origin and only available space. The study discovered that varying degree of efforts from government agencies, community self-help programmes and individuals are on-going to mitigate the flood hazard but the result of which are unnoticeable due to lack of policy framework, inadequate finance and crude nature of some of the efforts. An integrated approach involving relocation of residents of the High Risk Zone in areas ranging from 10-150 m radius around Rivers Ngada and Alou, flood reduction and living with flood concepts by others in the Middle Risk and Lower Risk Zones through progressive renewal, reclamation, construction of deep drainages and embankments, proper solid waste management and adequate development control strategies, are recommended as physical planning strategies much required to mitigate flood incidence and its attendants effects in Maiduguri.

  1. Building Adjustable Pre-storm Reservoir Flood-control Release Rules

    Science.gov (United States)

    Yang, Shun-Nien; Chang, Li-Chiu; Chang, Fi-John; Hsieh, Cheng-Daw

    2017-04-01

    Typhoons hit Taiwan several times every year, which could cause serious flood disasters. Because mountainous terrains and steep landforms can rapidly accelerate the speed of flood flow during typhoon events, rivers cannot be a stable source of water supply. Reservoirs become the most effective floodwater storage facilities for alleviating flood damages in Taiwan. The pre-storm flood-control release can significantly increase reservoir storage capacity available to store floodwaters for reducing downstream flood damage, while the uncertainties of total forecasted rainfalls are very high in different stages of an oncoming typhoon, which may cause the risk of water shortage in the future. This study proposes adjustable pre-storm reservoir flood-control release rules in three designed operating stages with various hydrological conditions in the Feitsui Reservoir, a pivot reservoir for water supply to Taipei metropolitan in Taiwan, not only to reduce the risk of reservoir flood control and downstream flooding but also to consider water supply. The three operating stages before an oncoming typhoon are defined upon the timings when: (1) typhoon news is issued (3-7days before typhoon hit); (2) the sea warning is issued (2-4 days before typhoon hit); and (3) the land warning is issued (1-2 days before typhoon hit). We simulate 95 historical typhoon events with 3000 initial water levels and build some pre-storm flood-control release rules to adjust the amount of pre-release based on the total forecasted rainfalls at different operating stages. A great number of simulations (68.4 millions) are conducted to extract their major consequences and then build the adjustable pre-storm reservoir flood-control release rules. Accordingly, given a total forecasted rainfall and a water level, reservoir decision makers can easily identify the corresponding rule to tell the amount of pre-release in any stage. The results show that the proposed adjustable pre-release rules can effectively

  2. Mathematical modelling of morphological changes and hyperconcentrated floods in the Yellow River

    NARCIS (Netherlands)

    Li, W.

    2014-01-01

    Hyperconcentrated flow/flood is a water-driven sediment transport phenomenon, which is characterized by high sediment concentrations between normal sediment-laden flow and debris/mud flow. In a hyperconcentrated flow, strong interactions exist between water flow, sediment, and river bed, which may n

  3. Floods and fish : recruitment and distribution of fish in the Volga River floodplain

    NARCIS (Netherlands)

    Górski, K.

    2010-01-01

    Natural river floodplains are among the most diverse and productive ecosystems on Earth and provide key habitats for foraging, spawning and as a nursery for many riverine fish species. Periodic flooding plays a principal role in the ecological processes in floodplain systems resulting in high produc

  4. Application of Integrated Flood Analysis System (IFAS) for Dungun River Basin

    Science.gov (United States)

    Hafiz, I.; Nor, N. D. M.; Sidek, L. M.; Basri, H.; K, F.; Hanapi, M. N.; L, Livia

    2013-06-01

    The Northeast monsoon happening during the months of October until January is the major rainy season found in the eastern part of Peninsular Malaysia. The Dungun river basin (1,858 km2) is exposed to this season thus experiencing characteristically regular flooding due to the prolong rainfall events. The annual rainfall over the river basins are 2,880 mm with great proportion falling in the months of December (19.4%). This study is to apply the Integrated Flood Analysis System (IFAS) model which Dungun river basin has been chosen for this study as the catchments have range of flood and relevant data that can be used to develop the model. The satellite data used in this study is provided by JAXA Global Rainfall Watch. The main feature of this real-time flood analysis model is the satellite-based rainfall data input employed during the model creation phase. The performance of the model for the river basins from satellite and ground-based rainfall data are compared using three error analysis methods.

  5. 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)

  6. Radionuclide contents in suspended sediments in relation to flood types in the lower Rhone River

    Energy Technology Data Exchange (ETDEWEB)

    Zebracki, Mathilde; Eyrolle-Boyer, Frederique; Antonelli, Christelle; Boullier, Vincent [IRSN / PRP-ENV, SESURE / LERCM, 13115 Saint-Paul-lez-Durance (France); De Vismes-Ott, Anne; Cagnat, Xavier [STEME / LMRE, 91400 Orsay (France)

    2013-07-01

    The aim of this work was to study the influence of watershed heterogeneity on the radionuclide contents of suspended particulate matter (SPM) in a large Mediterranean river. As the Rhone River catchment is characterized by a high climatic and geological heterogeneity, floods can be distinguished according to their geographic origins. Long-term time series of particles associated with radionuclides acquired in the framework of radiological surveillance provide a relevant dataset to investigate the variability of radionuclide contents. The SPM exported during Mediterranean floods differ from other floods as they display higher {sup 238}U and {sup 232}Th contents and the lowest activity ratio {sup 137}Cs/{sup (239+240)}Pu; these properties could be related to bedrock type and erosion process characteristics and/or to source term differentiation. (authors)

  7. Maximizing the usefulness of flood risk assessment for the River Vistula in Warsaw

    Science.gov (United States)

    Kiczko, A.; Romanowicz, R. J.; Osuch, M.; Karamuz, E.

    2013-06-01

    extent and flow values to be derived thus giving a cumulative assessment of flood risk. The methods are illustrated using the Warsaw reach of the River Vistula as a case study. The results indicate that the uncertainties have a substantial influence on flood risk assessment.

  8. Big Blue River at Shelbyville, Indiana flood-inundation geospatial datasets​

    Science.gov (United States)

    Fowler, Kathleen K.

    2017-01-01

    Digital flood-inundation maps for a 4.1-mile reach of the Big Blue River at Shelbyville, Indiana, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage on the Big Blue River at Shelbyville, Indiana (station number 03361500). Near-real-time stages at this streamgage may be obtained from the USGS National Water Information System at http://waterdata.usgs.gov/ or the National Weather Service (NWS) Advanced Hydrologic Prediction Service at http://water.weather.gov/ahps/, which also forecasts flood hydrographs at this site (SBVI3).Flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The hydraulic model was calibrated by using the most current stage-discharge relation at the Big Blue River at Shelbyville, Ind., streamgage. The calibrated hydraulic model was then used to compute 12 water-surface profiles for flood stages referenced to the streamgage datum and ranging from 9.0 feet, or near bankfull, to 19.4 feet, the highest stage of the current stage-discharge rating curve. 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 0.98-foot vertical accuracy and 4.9-foot horizontal resolution) to delineate the area flooded at each water level.The attached files on this landing page are the inputs and outputs for the U.S. Army Corps of Engineers HEC-RAS model used to create flood-inundation maps for the referenced report, https://doi.org/10.3133/sir20165166. There are two child items that contain final geospatial datasets for the flood-inundation maps

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

    Directory of Open Access Journals (Sweden)

    Silvia Di Francesco

    2016-07-01

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

  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. The effects of Missouri River mainstem reservoir system operations on 2011 flooding using a Precipitation-Runoff Modeling System model: Chapter K in 2011 Floods of the Central United States

    Science.gov (United States)

    Haj, Adel E.; Christiansen, Daniel E.; Viger, Roland J.

    2014-01-01

    In 2011 the Missouri River Mainstem Reservoir System (Reservoir System) experienced the largest volume of flood waters since the initiation of record-keeping in the nineteenth century. The high levels of runoff from both snowpack and rainfall stressed the Reservoir System’s capacity to control flood waters and caused massive damage and disruption along the river. The flooding and resulting damage along the Missouri River brought increased public attention to the U.S. Army Corps of Engineers (USACE) operation of the Reservoir System. To help understand the effects of Reservoir System operation on the 2011 Missouri River flood flows, the U.S. Geological Survey Precipitation-Runoff Modeling System was used to construct a model of the Missouri River Basin to simulate flows at streamgages and dam locations with the effects of Reservoir System operation (regulation) on flow removed. Statistical tests indicate that the Missouri River Precipitation-Runoff Modeling System model is a good fit for high-flow monthly and annual stream flow estimation. A comparison of simulated unregulated flows and measured regulated flows show that regulation greatly reduced spring peak flow events, consolidated two summer peak flow events to one with a markedly decreased magnitude, and maintained higher than normal base flow beyond the end of water year 2011. Further comparison of results indicate that without regulation, flows greater than those measured would have occurred and been sustained for much longer, frequently in excess of 30 days, and flooding associated with high-flow events would have been more severe.

  12. Flood mitigation through optimal control of a network of multi-purpose reservoirs by using Model Predictive Control

    Science.gov (United States)

    MyoLin, Nay; Rutten, Martine; van de Giesen, Nick

    2016-04-01

    Flooding is a common natural disaster in the world. Construction of reservoirs, sluice gates, dikes, embankments and sea walls are implemented to minimize loss of life and property in a flood event. Rather than completely relying on large structural measures, non-structural measures such as real time control of a reservoir system can also improve flood prevention and water supply in a river basin. In this paper, we present the optimal operation of a multi-reservoir system by using Model Predictive Control (MPC) and particular attention is focused on flood mitigation of the Sittaung River Basin, Myanmar. The main challenges are non-linearity in the dynamic behavior of the water system and exponential growth of computational complexity with the state and control dimension. To deal with an issue related to non-linearity, we applied simplified internal model based on linearization scheme with a large grid length. For solving curse of dimensionality, we utilize the reduced model in which the states of the system are reduced by considering outflows from uncontrolled catchments as disturbances in the water system. We also address the computational time for real time control by using large time step scheme. Simulation results indicate that this model is able to use for real time control of a reservoir system addressing trade-offs between the multiple objectives.

  13. Patterns of forest succession and impacts of flood in the Upper Mississippi River floodplain ecosystem

    Science.gov (United States)

    Yin, Y.; Wu, Y.; Bartell, S.M.; Cosgriff, R.

    2009-01-01

    The widespread loss of oak-hickory forests and the impacts of flood have been major issues of ecological interest concerning forest succession in the Upper Mississippi River (UMR) floodplain. The data analysis from two comprehensive field surveys indicated that Quercus was one of the dominant genera in the UMR floodplain ecosystem prior to the 1993 flood and constituted 14% of the total number of trees and 28% of the total basal area. During the post-flood recovery period through 2006, Quercus demonstrated slower recovery rates in both the number of trees (4%) and basal area (17%). In the same period, Carya recovered greatly from the 1993 flood in terms of the number of trees (11%) and basal area (2%), compared to its minor status before the flood. Further analyses suggested that different species responded to the 1993 flood with varying tolerance and different succession strategies. In this study, the relation of flood-caused mortality rates and DBH, fm(d), can be expressed in negative exponential functions for each species. The results of this research also indicate that the growth functions are different for each species and might also be different between pre- and post-flood time periods. These functions indicate different survival strategies and emergent properties in responding to flood impacts. This research enhances our understanding of forest succession patterns in space and time in the UPR floodplain. And such understanding might be used to predict long-term impacts of floods on UMR floodplain forest dynamics in support of management and restoration. ?? 2009 Elsevier B.V.

  14. Costs and benefits of river flood risk management at the global scale

    Science.gov (United States)

    Ward, P.

    2015-12-01

    Floods cause billions of dollars of economic damage each year, and this is expected to increase in the future due to socioeconomic development and climate change‎. To limit these losses, and to protect people and their livelihoods from flooding, adaptation in flood risk management systems is required that takes into account both current and future risk. Whilst several global scale flood risk models have now been developed to assess both current and future river flood risk, to date none of these include currently installed or future flood risk management measures, nor their costs and benefits. In this contribution, a new modelling framework is presented for assessing both the costs and benefits of flood risk management at the global scale, which employs a cascade of models to provide first-cut estimates of the costs and benefits of adaptation by means of hazard reduction through the construction of dikes. The modeling framework is first used to assess what protection standards would be required in the future per state, in order to keep future flood risk constant at today's levels, and the costs and benefits associated with such a strategy. In a second analysis, flood risk protection standards are calculated per state that optimize the net present value of adaptation. The potential usefulness and limitations of the results for practical applications are discussed, as well as key avenues for future developments. In particular, recent research has shown flood risk itself to be non-stationary, being influenced by oscillations in climate variability caused by phenomenon such as El Niño Southern Oscillation (ENSO). The results of the research will be discussed within the context of climate-driven ENSO variability.

  15. Flood Frequency Analysis For Partial Duration Series In Ganjiang River Basin

    Science.gov (United States)

    zhangli, Sun; xiufang, Zhu; yaozhong, Pan

    2016-04-01

    Accurate estimation of flood frequency is key to effective, nationwide flood damage abatement programs. The partial duration series (PDS) method is widely used in hydrologic studies because it considers all events above a certain threshold level as compared to the annual maximum series (AMS) method, which considers only the annual maximum value. However, the PDS has a drawback in that it is difficult to define the thresholds and maintain an independent and identical distribution of the partial duration time series; this drawback is discussed in this paper. The Ganjiang River is the seventh largest tributary of the Yangtze River, the longest river in China. The Ganjiang River covers a drainage area of 81,258 km2 at the Wanzhou hydrologic station as the basin outlet. In this work, 56 years of daily flow data (1954-2009) from the Wanzhou station were used to analyze flood frequency, and the Pearson-III model was employed as the hydrologic probability distribution. Generally, three tasks were accomplished: (1) the threshold of PDS by percentile rank of daily runoff was obtained; (2) trend analysis of the flow series was conducted using PDS; and (3) flood frequency analysis was conducted for partial duration flow series. The results showed a slight upward trend of the annual runoff in the Ganjiang River basin. The maximum flow with a 0.01 exceedance probability (corresponding to a 100-year flood peak under stationary conditions) was 20,000 m3/s, while that with a 0.1 exceedance probability was 15,000 m3/s. These results will serve as a guide to hydrological engineering planning, design, and management for policymakers and decision makers associated with hydrology.

  16. River flood events in Thailand and Bangladesh observed by CryoSat

    Science.gov (United States)

    Andersen, O. B.; Nielsen, K.; Villadsen, H.; Stenseng, L.; Knudsen, P.

    2014-12-01

    The high along track resolution of the SIRAL altimeter carried on-board CryoSat-2 offers a wide range of unique opportunities for satellite monitoring of inland water level. This study focuses on the ability of CryoSat-2 to detect the effects of flood events such as increased river levels and inundation of land. Here we study two flood events; the Bangladesh flood event of June 2012 and the flooding in Thailand that lasted between July 2011 and January 2012. The flooding in these areas was caused by abnormal monsoonal rainfall and affected millions of people. We process CryoSat-2 level 1b SAR mode data to derive water levels for the areas and compare these levels before, during and after the flooding events. Other parameters such as the backscatter coefficient and pulse peakiness are also considered. To verify the extent of the flooding observed by CryoSat-2 we compare with independent sources such as Landsat images.

  17. Erosion and sedimentation during the September 2015 flooding of the Kinu River, central Japan

    Science.gov (United States)

    Dan Matsumoto; Sawai, Yuki; Yamada, Masaki; Namegaya, Yuichi; Shinozaki, Tetsuya; Takeda, Daisuke; Fujino, Shigehiro; Tanigawa, Koichiro; Nakamura, Atsunori; Pilarczyk, Jessica E.

    2016-01-01

    Erosional and sedimentary features associated with flooding have been documented in both modern and past cases. However, only a few studies have demonstrated the relationship between these features and the corresponding hydraulic conditions that produced them, making it difficult to evaluate the magnitude of paleo-flooding. This study describes the characteristics associated with inundation depth and flow direction, as well as the erosional and sedimentary features resulting from the disastrous flooding of the Kinu River, central Japan, in September 2015. Water levels rose rapidly due to heavy rainfall that eventually overtopped, and subsequently breached, a levee in Joso City, causing destructive flooding on the surrounding floodplain. Distinctive erosional features are found next to the breached levee, while depositional features, such as a sandy crevasse-splay deposit are found further away from the breach. The deposit can be divided into three units based on sedimentary facies. The vertical and lateral changes of these sedimentary facies may be the result of temporal and spatial changes associated with flow during the single flooding event. These observations and quantitative data provide information that can be used to reveal the paleohydrology of flood deposits in the stratigraphic record, leading to improved mitigation of future flooding disasters. PMID:27677769

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2005-03-01

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

  19. Novel early flood warning in the Huaihe River basin in east-central China using the TIGGE database

    Science.gov (United States)

    He, Y.; Cloke, H.; Li, Z.; Wetterhall, F.; Pappenberger, F.

    2009-04-01

    Flooding is a wide spread and devastating natural disaster worldwide. Floods that took place in the last decade in China were ranked the worst amongst recorded floods worldwide in terms of the number of human fatalities and economic losses (Munich Re-Insurance). Rapid economic development and population expansion into low lying flood plains has worsened the situation. The last decade has seen an increase in flood preparedness across all levels of society in China. Current conventional flood prediction systems in China are neither suited to the perceptible climate variability nor the rapid pace of urbanization sweeping the country. Flood prediction systems from short-term (a few hours) to medium-term (a few days) need to be revisited and adapted to changing socio-economic and hydro-climatic realities. The latest technology requires implementation of multiple numerical weather prediction systems. The availability of a number of global ensemble weather prediction systems through the ‘THORPEX Interactive Grand Global Ensemble' (TIGGE) offers a good opportunity for an effective state-of-the-art early forecasting system. A prototype of a Novel Flood Early Warning System (NEWS) using the TIGGE database is tested in the Huai River basin located in east-central China. It is the first early flood warning system in China that uses the massive TIGGE database cascaded with river catchment models, the Xinanjiang model and a 1-D hydraulic model, to predict river discharge and flood inundation. Results from selected flood events will be presented.

  20. Flood of July 27-31, 2006, on the Grand River near Painesville, Ohio

    Science.gov (United States)

    Ebner, Andrew D.; Sherwood, James M.; Astifan, Brian; Lombardy, Kirk

    2007-01-01

    Two separate weather systems produced storms resulting in more than 11 inches of rain in parts of Lake County, Ohio, on July 27-28, 2006. As a result of the storms and ensuing flooding caused by the weather systems, the counties of Lake, Geauga, and Ashtabula were declared Federal and State disaster areas, with damages estimated at $30 million and one fatality in Lake County. About 600 people were evacuated in Lake County. The U.S. Geological Survey streamflow-gaging station at Grand River near Painesville, Ohio (station 04212100), had a record peak stage of 19.35 feet (elevation, 614.94 feet), with a record peak streamflow of 35,000 cubic feet per second, and an estimated recurrence interval of approximately 500 years. This report describes the meteorological factors that resulted in severe flooding on the Grand River near Painesville from July 27 to July 31, 2006, and addresses the damages caused by the storms and flooding. Peak-stage, peak-streamflow, and recurrence-interval data are reported for the Grand River near Painesville. A plot of high-water marks is also presented for the Grand River in a reach that includes the City of Painesville, Painesville Township, the Village of Fairport Harbor, and the Village of Grand River.

  1. Sele coastal plain flood risk due to wave storm and river flow interaction

    Science.gov (United States)

    Benassai, Guido; Aucelli, Pietro; Di Paola, Gianluigi; Della Morte, Renata; Cozzolino, Luca; Rizzo, Angela

    2016-04-01

    Wind waves, elevated water levels and river discharge can cause flooding in low-lying coastal areas, where the water level is the interaction between wave storm elevated water levels and river flow interaction. The factors driving the potential flood risk include weather conditions, river water stage and storm surge. These data are required to obtain inputs to run the hydrological model used to evaluate the water surface level during ordinary and extreme events regarding both the fluvial overflow and storm surge at the river mouth. In this paper we studied the interaction between the sea level variation and the river hydraulics in order to assess the location of the river floods in the Sele coastal plain. The wave data were acquired from the wave buoy of Ponza, while the water level data needed to assess the sea level variation were recorded by the tide gauge of Salerno. The water stages, river discharges and rating curves for Sele river were provided by Italian Hydrographic Service (Servizio Idrografico e Mareografico Nazionale, SIMN).We used the dataset of Albanella station (40°29'34.30"N, 15°00'44.30"E), located around 7 km from the river mouth. The extreme river discharges were evaluated through the Weibull equation, which were associated with their return period (TR). The steady state river water levels were evaluated through HEC-RAS 4.0 model, developed by Hydrologic Engineering Center (HEC) of the United States Army Corps of Engineers Hydrologic Engineering Center (USACE,2006). It is a well-known 1D model that computes water surface elevation (WSE) and velocity at discrete cross-sections by solving continuity, energy and flow resistance (e.g., Manning) equation. Data requirements for HEC-RAS include topographic information in the form of a series of cross-sections, friction parameter in the form of Manning's n values across each cross-section, and flow data including flow rates, flow change locations, and boundary conditions. For a steady state sub

  2. Flood of July 2016 in northern Wisconsin and the Bad River Reservation

    Science.gov (United States)

    Fitzpatrick, Faith A.; Dantoin, Eric D.; Tillison, Naomi; Watson, Kara M.; Waschbusch, Robert J.; Blount, James D.

    2017-06-06

    Heavy rain fell across northern Wisconsin and the Bad River Reservation on July 11, 2016, as a result of several rounds of thunderstorms. The storms caused major flooding in the Bad River Basin and nearby tributaries along the south shore of Lake Superior. Rainfall totals were 8–10 inches or more and most of the rain fell in an 8-hour period. A streamgage on the Bad River near Odanah, Wisconsin, rose from 300 cubic feet per second to a record peak streamflow of 40,000 cubic feet per second in only 15 hours. Following the storms and through September 2016, personnel from the U.S. Geological Survey and Bad River Tribe Natural Resources Department recovered and documented 108 high-water marks near the Bad River Reservation. Many of these high-water marks were used to create three flood-inundation maps for the Bad River, Beartrap Creek, and Denomie Creek for the Bad River Reservation in the vicinity of the community of Odanah.

  3. Rebuilding Habitat and Shoreline Resilience through Improved Flood Control Project

    Science.gov (United States)

    Information about the SFBWQP Rebuilding Habitat and Shoreline Resilience through Improved Flood Control Project, part of an EPA competitive grant program to improve SF Bay water quality focused on restoring impaired waters and enhancing aquatic resources.

  4. Flood Control Structures, POD 77, Published in 2001, Duchesne County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Flood Control Structures dataset, was produced all or in part from Other information as of 2001. It is described as 'POD 77'. Data by this publisher are often...

  5. A remote sensing approach for connecting the historic 2011 Mississippi River flood to wetland sedimentation on the Delta

    Science.gov (United States)

    Falcini, Federico; Colella, Simone; Volpe, Gianluca; Khan, Nicole; Macelloni, Leonardo; Santoleri, Rosalia; Horton, Benjamin; Jerolmack, Douglas

    2013-04-01

    Wetlands in the Mississippi River deltaic plain are deteriorating in part because levees and control structures starve them of sediment. In Spring of 2011 a record breaking flood brought discharge on the lower Mississippi River to dangerous levels, forcing managers to divert additional water to the adjacent Atchafalaya River Basin. Here we quantify differences between the Mississippi and Atchafalaya River inundation and sediment-plume patterns using field-calibrated satellite data, and assess the impact these outflows had on wetland sedimentation. Since standard products available from MyOcean were not suitable for this purpose an ad hoc processing was developed to establish a relationship between field suspended sediment concentration (SSC) data and the corrected MODIS reflectance at 645 nm. We show that the focused, high-momentum jet from the leveed Mississippi delivered sediment far offshore. In contrast, the plume from the Atchafalaya was more diffuse; diverted water inundated a large area, and sediment was trapped within the coastal current. Maximum sedimentation (up to several centimetres) occurred in the Atchafalaya Basin despite the larger sediment load carried by the Mississippi. Little accumulation occurred along the shoreline between these river sources. The correspondence between zones of high shoreline deposition, and coastal SSC patterns indentified from satellite data, is strongly suggestive of plume-derived deposition on marshes. Our findings allow us to set an hydrodynamic theory that provides a mechanistic link between river-mouth dynamics and wetland sedimentation patterns, which is relevant for plans to restore deltaic wetlands.

  6. Global warming increases the frequency of river floods in Europe

    OpenAIRE

    Alfieri, L.; Burek, P.; Feyen, L.; Forzieri, G.

    2015-01-01

    EURO-CORDEX (Coordinated Downscaling Experiment over Europe), a new generation of downscaled climate projections, has become available for climate change impact studies in Europe. New opportunities arise in the investigation of potential effects of a warmer world on meteorological and hydrological extremes at regional scales. In this work, an ensemble of EURO-CORDEX RCP8.5 scenarios is used to drive a distributed hydrological model and assess the projected changes in flood haza...

  7. Mapping rivers with a potential danger of damage by flash flooding and debris flows

    Science.gov (United States)

    Peereboom, I.; Svegården, J.; Fergus, T.

    2009-04-01

    Landforms associated with past debris flows such as alluvial fans are typical locations for settlements in Norway. Flash floods with associated debris flows in small and steep river catchments cause a great deal of damage to infrastructure and housing located on alluvial fans. The Norwegian Water Resources and Energy Resources Directorate (NVE) is the national authority responsible for flood and landslide hazard management in Norway. Mapping areas with a risk of damage from flooding and landslides coupled with advice on land use planning, results in better land use practices and an increased awareness of the potential hazard among local authorities and citizens. Methods for mapping floodplain inundation for large rivers are well developed. This is not the case for rivers with small and steep catchments with a potential for high rates of erosion and sediment transport. A method for identifying and mapping rivers with a potential danger of flash flooding and associated debris flows is currently being developed at NVE. The resultant maps will assist local authorities in the first step in land use planning where they are required to identify if there is a potential hazard in the area. The method makes use of spatial data available for the whole country and is based on a 25*25 m terrain model. The method is based on two simple assumptions adapted to the available data: i) Under normal hydraulic conditions there is a balance between processes of erosion and sedimentation. A debris flow will first occur when this balance is disturbed. This is quantified by the relative difference between the discharge of an extreme flood and floods that occur more frequently, ie. if the difference is large the probability of a debris flow occurring is greater and vice versa. ii) Steep rivers with a large difference in height between cells have more energy available for erosion and sediment transport and therefore a larger potential for erosion and sediment transport than less steep rivers

  8. Detection of Flooding Responses at the River Basin Scale Enhanced by Land use Change

    Science.gov (United States)

    McCormick, Brian C.; Eshleman, Keith N.; Griffith, Jeff L.; Townsend, Philip A.

    2009-01-01

    The Georges Creek watershed (area 187.5 sq km) in western Maryland (United States) has experienced land use changes (>17% of area) associated with surface mining of coal. The adjacent Savage River watershed (area 127.2 sq km) is unmined. Moments of flood frequency distributions indicated that climatic variability affected both watersheds similarly. Normalizing annual maximum flows by antecedent streamflow and causative precipitation helped identify trends in flooding response. Analysis of contemporary storm events using Next Generation Weather Radar (NEXRAD) stage III precipitation data showed that Georges Creek floods are characterized by higher peak runoff and a shorter centroid lag than Savage River floods, likely attributable to differences in current land use. Interestingly, Georges Creek produces only two thirds of the storm-flow volume as Savage River, apparently because of infiltration into abandoned deep mine workings and an associated transbasin diversion constructed circa 1900. Empirical trend analysis is thus complicated by both hydroclimatic variability and the legacy of deep mining in the basin.

  9. St. Joseph River at Elkhart, Indiana, flood-inundation HEC-RAS Model

    Science.gov (United States)

    Martin, Zachary W.

    2017-01-01

    Digital flood-inundation maps for a 6.6-mile reach of the St. Joseph River at Elkhart, Indiana were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage 04101000, St. Joseph River at Elkhart, Ind. 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 at http:/water.weather.gov/ahps/, which also forecasts flood hydrographs at this site (NWS site EKMI3). Flood profiles were computed for the USGS streamgage 04101000, St. Joseph River at Elkhart, Ind., reach by means of a one-dimensional step-backwater hydraulic modeling software developed by the U.S. Army Corps of Engineers. The hydraulic model was calibrated using the current stage-discharge rating at the USGS streamgage 04101000, St. Joseph River at Elkhart, Ind. The hydraulic model was then used to compute 6 water-surface profiles for flood stages at 1-foot (ft) intervals referenced to the streamgage datum ranging from 23.0 ft (the NWS “action stage”) to 28.0 ft, which is the highest stage interval of the current USGS stage-discharge rating curve and 1 ft higher than the NWS “major flood stage.” 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 0.49-ft root mean squared error and 4.9-ft horizontal resolution) to delineate the area flooded at each stage. The availability of these maps, along with Internet information regarding current stage from the USGS streamgage

  10. Floods of the Maros river in the early modern and modern period (16th-20th centuries)

    Science.gov (United States)

    Kiss, Andrea

    2016-04-01

    In the poster presentation a series of historical and recent floods of the Maros river, with special emphasis on the flood events occurred on the lower sections, are presented. Similar to the Hungarian flood databases of the Middle-Danube and Lower-Tisza, the main sources of investigations are the institutional (legal-administrative) documentary evidence (e.g. Szeged and Makó town council protocols and related administrative documentation, Csanád County meeting protocols) mainly from the late 17th-early 18th century onwards. However, in case of the Maros river there is an increased importance of narrative sources, with special emphasis on the early modern period (16th-17th century): in this case the (mainly Transylvanian) narratives (chronicles, diaries, memoires etc.) written by aristocrats, other noblemen and town citizens have particular importance. In the presentation the frequency of detected flood events, from the mid-16th century onwards (with an outlook on sporadic medieval evidence), is provided; moreover, a 3-scaled magnitude classification and a seasonality analysis are also presented. Floods of the Maros river, especially those of the lower river sections, often cannot be understood and discussed without the floods of the (Lower-)Tisza; thus, a comparison of the two flood series are also a subject of discussion. Unlike the Lower-Tisza, the Maros is prone to winter and early spring ice jam floods: since the floods that belonged to this type (similar to those of the Middle-Danube at Budapest) were the most destructive among the flood events of the river, this flood type, and the greatest flood events (e.g. 1751-1752, 1784) are also presented in more detail.

  11. Impact of dams on flood occurrence of selected rivers in the United States

    Science.gov (United States)

    Mei, Xuefei; Van Gelder, P. H. A. J. M.; Dai, Zhijun; Tang, Zhenghong

    2016-10-01

    A significant large number of dams have been constructed in the past two centuries in the United States. These dams' ability to regulate downstream flooding has received world-wide attention. In this study, data from 38 rivers distributed over the entire conterminous Untied States with extensive pre- and post-dam annual peak discharge records, were collected to research the impacts of various dams on the flood behaviors at a national scale. The results indicate that dams have led to significant reductions in flood magnitude for nearly all of the sites; the decrease rate in the mean of annual peak discharge varies between 7.4% and 95.14%, except for the Dead River, which increased by 1.46%. Because of dams' effectiveness, the probability density curve of annual peak flow changes from a flat to peaked shape because both the range and magnitude of high discharges are decreased. Moreover, the potential impact of dams on flood characteristics were closely related to the dam's geographic location and function, the ratio of the storage capacity of the dam to the mean annual runoff of the river (C/R), and the ratio of reservoir storage capacity to the area of its drainage (C/D). Specifically, the effects of dams on annual peak flows were more related to latitude than longitude. Compared with dams built for other purposes, the dam exclusively used for flood management cut off more flood peaks. Increases in the ratios of C/R and C/D increased the degree of modification of annual maximum discharge.

  12. Development of Hydrological Model of Klang River Valley for flood forecasting

    Science.gov (United States)

    Mohammad, M.; Andras, B.

    2012-12-01

    This study is to review the impact of climate change and land used on flooding through the Klang River and to compare the changes in the existing river system in Klang River Basin with the Storm water Management and Road Tunnel (SMART) which is now already operating in the city centre of Kuala Lumpur. Klang River Basin is the most urbanized region in Malaysia. More than half of the basin has been urbanized on the land that is prone to flooding. Numerous flood mitigation projects and studies have been carried out to enhance the existing flood forecasting and mitigation project. The objective of this study is to develop a hydrological model for flood forecasting in Klang Basin Malaysia. Hydrological modelling generally requires large set of input data and this is more often a challenge for a developing country. Due to this limitation, the Tropical Rainfall Measuring Mission (TRMM) rainfall measurement, initiated by the US space agency NASA and Japanese space agency JAXA was used in this study. TRMM data was transformed and corrected by quantile to quantile transformation. However, transforming the data based on ground measurement doesn't make any significant improvement and the statistical comparison shows only 10% difference. The conceptual HYMOD model was used in this study and calibrated using ROPE algorithm. But, using the whole time series of the observation period in this area resulted in insufficient performance. The depth function which used in ROPE algorithm are then used to identified and calibrated using only unusual event to observed the improvement and efficiency of the model.

  13. Declining vulnerability to river floods and the global benefits of adaptation

    Science.gov (United States)

    Jongman, Brenden; Winsemius, Hessel; Aerts, Jeroen; Coughlan de Perez, Erin; Van Aalst, Maarten; Kron, Wolfgang; Ward, Philip

    2016-04-01

    The global impacts of river floods are substantial and rising. Effective adaptation to the increasing risks requires an in-depth understanding of the physical and socioeconomic drivers of risk. Whilst the modeling of flood hazard and exposure has improved greatly, compelling evidence on spatiotemporal patterns in vulnerability of societies around the world is lacking. Hence, the effects of vulnerability on global flood risk are not fully understood, and future projections of fatalities and losses available today are based on simplistic assumptions or do not include vulnerability. In this study, we show that trends and fluctuations in vulnerability to river floods around the world can be estimated by dynamic high-resolution modeling of flood hazard and exposure. We show that fatalities and losses as a share of exposed population and gross domestic product are decreasing with rising income. We also show that there is a tendency of convergence in vulnerability levels between low- and high-income countries. Based on these findings, we simulate future flood impacts per country using traditional assumptions of static vulnerability through time, but also using future assumptions on reduced vulnerability in the future. We show that future risk increases can be largely contained using effective disaster risk reduction strategies, including a reduction of vulnerability. The study was carried out using the global flood risk model, GLOFRIS, combined with high-resolution time-series maps of hazard and exposure at the global scale. Based on: Jongman et al., 2015. Proceedings of the National Academy of Sciences of the United States of America, doi:10.1073/pnas.1414439112.

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

    Directory of Open Access Journals (Sweden)

    Farid Mohammad

    2017-01-01

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

  15. Outburst Flood Simulation Model for Optimizing the Solo River Floods Emergency Response Activities

    Directory of Open Access Journals (Sweden)

    Yuli Priyana

    2016-08-01

    Full Text Available This study aims to develop flood inundation based on several flood level. The results of this study are: (a land use in the study area is divided into (1 urban area (the Business Area which includes regional administrative center, shopping area, and office area, (2 residential areas (single home region, the region multi- unit house (residence, settlement areas and apartments, (3 industrial estate (industrial estates are less dense and dense industrial area, (4 the surface area covered with vegetation (forest - thicket, meadow area, and the area of land productive rice fields and fields, (5 the area of open land and vacant land that is intended (the city park , cemetery and park area, and (6 transportation area and the pavement surface area (area train station and bus terminal region, (b the preparation of spatial database in this study in the form of data or data vector altitude of Digital Elevation Model (DEM. District of Jebres there are 56 points of elevation and District of Pasar Kliwon there are 48 points of elevation. Elevation of the study area ranged from 88,9 mpdal up to 127.65 mdpal and (c the higher the flood inundation scenarios impact on land use in the study area are also getting bigger. Most obvious impact under scenario 2 m area of 296 601 m , while the smallest impact under scenario 1 m with an area of 77 693 m 2 2 impact. Extensive simulation results based on the total impact amounts to 544 756 m.

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

    Science.gov (United States)

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

    2005-03-01

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

  17. 33 CFR 239.7 - Separation of flood control works from urban drainage.

    Science.gov (United States)

    2010-07-01

    ... COVERED FLOOD CONTROL CHANNELS § 239.7 Separation of flood control works from urban drainage. Covered channels are likely to be considered in boundary areas demarking urban drainage and flood control... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Separation of flood control...

  18. Impact of the Mekong River flow alteration on the Tonle Sap flood pulse.

    Science.gov (United States)

    Kummu, Matti; Sarkkula, Juha

    2008-05-01

    Rapid development in the upper reaches of the Mekong River, in the form of construction of large hydropower dams and reservoirs, large irrigation schemes, and rapid urban development, is putting water resources under stress. Recent studies have concluded that these developments will lead to flow alterations in the Mekong River. These flow alterations would threaten the sensitive ecosystems downstream, particularly Tonle Sap River, Tonle Sap Lake, its floodplain, and its gallery forest and protected areas, by changing the flood-pulse system of the lake. This article estimates the changes in parameters of the Tonle Sap flood pulse due to the aforementioned flow alterations. The impacts on the flooded area and loss of gallery forest and protected areas were analyzed using geographic information system-based methods. Relatively small rises in the dry-season lake water level would permanently inundate disproportionately large areas of floodplain, rendering it inaccessible to floodplain vegetation and eroding the productivity basis of the ecosystem. It is highly important to maintain the natural hydrological pattern of the Mekong River, particularly the dry-season water levels, to preserve Tonle Sap Lake's ecosystem productivity.

  19. Deriving Flood-Mediated Connectivity between River Channels and Floodplains: Data-Driven Approaches

    Science.gov (United States)

    Zhao, Tongtiegang; Shao, Quanxi; Zhang, Yongyong

    2017-03-01

    The flood-mediated connectivity between river channels and floodplains plays a fundamental role in flood hazard mapping and exerts profound ecological effects. The classic nearest neighbor search (NNS) fails to derive this connectivity because of spatial heterogeneity and continuity. We develop two novel data-driven connectivity-deriving approaches, namely, progressive nearest neighbor search (PNNS) and progressive iterative nearest neighbor search (PiNNS). These approaches are illustrated through a case study in Northern Australia. First, PNNS and PiNNS are employed to identify flood pathways on floodplains through forward tracking. That is, progressive search is performed to associate newly inundated cells in each time step to previously inundated cells. In particular, iterations in PiNNS ensure that the connectivity is continuous - the connection between any two cells along the pathway is built through intermediate inundated cells. Second, inundated floodplain cells are collectively connected to river channel cells through backward tracing. Certain river channel sections are identified to connect to a large number of inundated floodplain cells. That is, the floodwater from these sections causes widespread floodplain inundation. Our proposed approaches take advantage of spatial-temporal data. They can be applied to achieve connectivity from hydro-dynamic and remote sensing data and assist in river basin planning and management.

  20. Ice jam-caused fluvial gullies and scour holes on northern river flood plains

    Science.gov (United States)

    Smith, Derald G.; Pearce, Cheryl M.

    2002-01-01

    Two anomalous fluvial landforms, gullies and scour holes, eroded into flood plains bordering meandering and braiding river channels have not been previously reported. We observed these features along the Milk River in southern Alberta, Canada, and northern Montana, USA, which has a history of frequent (50% probability of recurrence) and high-magnitude (12% probability of recurrence greater than bankfull) ice jam floods. Gullies have palmate and narrow linear shapes with open-ends downvalley and measure up to 208 m long×139 m wide×3.5 m deep (below bankfull). Channel ice jams reroute river water across meander lobes and cause headward gully erosion where flow returns to the main channel. Erosion of the most recent gully was observed during the record 1996 ice breakup flood and ice jams. Scour holes (bowl-shaped, closed depressions), eroded by water vortices beneath and between grounded ice jam blocks, measure up to 91 m long×22 m wide×4.5 m deep. Ice jam-caused gullies may be precursors to the formation of U-shaped oxbow lakes and multiple channels, common in many northern rivers.

  1. Physically-based Flood Modeling Driven by Radar Rainfall in the Upper Guadalupe River Basin, Texas

    Science.gov (United States)

    Sharif, H. O.; Chintalapudi, S.; El Hassan, A.

    2011-12-01

    The upstream portion of the Guadalupe River Basin (Upper Guadalupe River Basin) is prone to frequent flooding due to its physiographic properties (thin soils, exposed bedrock, and sparse vegetation). The Upper Guadalupe River watershed above Comfort, Texas drains an area of 2,170 square kilometers. This watershed is located at the central part of the Texas Hill Country. This study presents hydrologic analysis of the June 2002, November-2004, and August-2007 flood events that occurred in Upper Guadalupe River Basin. The physically based, distributed-parameter Gridded Surface Subsurface Hydrologic Analysis (GSSHA) hydrologic model was used to simulate the above flooding events. The first event was used in model while the other two were used for validation. GSSHA model was driven by both rain gauge and Multi-sensor Precipitation Estimator (MPE) rainfall inputs. Differences in simulation results were compared in terms of the hydrographs at different locations in the basin as well as the spatial distribution of hydrologic processes. GSSHA simulations driven by MPE rainfall match very well the USGS observed hydrograph. GSSHA simulation driven by rain gauge rainfall for June-2002 storm event underestimated the peak flow.

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

    Science.gov (United States)

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

    2014-05-01

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

  3. Flood-inundation maps for the Meramec River at Valley Park and at Fenton, Missouri, 2017

    Science.gov (United States)

    Dietsch, Benjamin J.; Sappington, Jacob N.

    2017-09-29

    Two sets of digital flood-inundation map libraries that spanned a combined 16.7-mile reach of the Meramec River that extends upstream from Valley Park, Missouri, to downstream from Fenton, Mo., were created by the U.S. Geological Survey (USGS) in cooperation with the U.S. Army Corps of Engineers, St. Louis Metropolitan Sewer District, Missouri Department of Transportation, Missouri American Water, and Federal Emergency Management Agency Region 7. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science website at https://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the cooperative USGS streamgages on the Meramec River at Valley Park, Mo., (USGS station number 07019130) and the Meramec River at Fenton, Mo. (USGS station number 07019210). Near-real-time stage data at these streamgages may be obtained from the USGS National Water Information System at https://waterdata.usgs.gov/nwis or the National Weather Service (NWS) Advanced Hydrologic Prediction Service at http:/water.weather.gov/ahps/, which also forecasts flood hydrographs at these sites (listed as NWS sites vllm7 and fnnm7, respectively).Flood profiles were computed for the stream reaches by means of a calibrated one-dimensional step-backwater hydraulic model. The model was calibrated using a stage-discharge relation at the Meramec River near Eureka streamgage (USGS station number 07019000) and documented high-water marks from the flood of December 2015 through January 2016.The calibrated hydraulic model was used to compute two sets of water-surface profiles: one set for the streamgage at Valley Park, Mo. (USGS station number 07019130), and one set for the USGS streamgage on the Meramec River at Fenton, Mo. (USGS station number 07019210). The water-surface profiles were produced for stages at 1-foot (ft) intervals referenced to the datum from each streamgage and

  4. Production and decomposition of forest litter fall on the Apalachicola River flood plain, Florida: Chapter B, Apalachicola River quality assessment

    Science.gov (United States)

    Elder, John F.; Cairns, Duncan J.

    1982-01-01

    Measurements of litter fall (leaves and other particulate organic material) and leaf decomposition were made on the bottom-land hardwood swamp of the Apalachicola River flood plain in 1979-80. Litter fall was collected monthly from nets located in 16 study plots. The plots represented five forest types in the swamp and levee areas of the Apalachicola River flood plain. Forty-three species of trees, vines, and other plants contributed to the total litter fall, but more than 90 percent of the leaf material originated from 12 species. Nonleaf material made up 42 percent of the total litter fall. Average litter fall was determined to be 800 grams per square meter per year, resulting in an annual deposition of 3.6 ? 105 metric tons of organic material in the 454-square-kilometer flood plain. The levee communities have less tree biomass but greater tree diversity than do swamp communities. The levee vegetation, containing less tree biomass, produces slightly more litter fall per unit of ground surface area than does the swamp vegetation. The swamps are dominated by three genera: tupelo (Nyssa), cypress (Taxodium) and ash (Fraxinus). These genera account for more than 50 percent of the total leaf fall in the flood plain, but they are the least productive, on a weight-perbiomass basis, of any of the 12 major leaf producers. Decomposition rates of leaves from five common floodplain tree species were measured using a standard leaf-bag technique. Leaf decomposition was highly species dependent. Tupelo (Nyssa spp.) and sweetgum (Liquidambar styraciflua) leaves decomposed completely in 6 months when flooded by river water. Leaves of baldcypress (Taxodium distichum) and diamond-leaf oak (Quercus laurifolia) were much more resistant. Water hickory (Carya aquatica) leaves showed intermediate decomposition rates. Decomposition of all species was greatly reduced in dry environments. Carbon and biomass loss rates from the leaves were nearly linear over a 6-month period, but nitrogen

  5. Multi-objective scheduling mode utilization of cascaded reservoir group in upper Yellow River during ice jam flood prevention

    Science.gov (United States)

    Gao, Shichun; Dong, Qianjin; Fu, Xiang; Ai, Ze

    2010-05-01

    The cascaded reservoir group in upper Yellow River has the integrated function of ice jam flood prevention and power generation. The main factors which affect the utilization of the ice jam flood prevention volume of Liujiaxia reservoir are analyzed during the period of ice jam flood prevention, based on the input of new power station in upper Yellow River, the method of cascaded compensating scheduling are applied and the relation curve between the ice jam flood prevention volume and the cascaded output power of Liujiaxia reservoir is calculated, and the scheduling multi-objective solution set for the reservoir is obtained. On this basis, the new scheduling mode solving the reservoir integrated scheduling problem in upper Yellow River during the period of ice jam flood prevention is discussed. Comparing with the regular scheduling results, the new scheduling mode based on multi-objective solution set has the outstanding advantage in solving the problem of multi-objective scheduling of cascaded reservoir group.

  6. Hospital infection prevention and control issues relevant to extensive floods.

    Science.gov (United States)

    Apisarnthanarak, Anucha; Mundy, Linda M; Khawcharoenporn, Thana; Glen Mayhall, C

    2013-02-01

    The devastating clinical and economic implications of floods exemplify the need for effective global infection prevention and control (IPC) strategies for natural disasters. Reopening of hospitals after excessive flooding requires a balance between meeting the medical needs of the surrounding communities and restoration of a safe hospital environment. Postflood hospital preparedness plans are a key issue for infection control epidemiologists, healthcare providers, patients, and hospital administrators. We provide recent IPC experiences related to reopening of a hospital after extensive black-water floods necessitated hospital closures in Thailand and the United States. These experiences provide a foundation for the future design, execution, and analysis of black-water flood preparedness plans by IPC stakeholders.

  7. Storms, floods, and the science of atmospheric rivers

    Science.gov (United States)

    Ralph, F.M.; Dettinger, M.D.

    2011-01-01

    Imagine a stream of water thousands of kilometers long and as wide as the distance between New York City and Washington, D. C., flowing toward you at 30 miles per hour. No, this is not some hypothetical physics problemit is a real river, carrying more water than 7-15 Mississippi Rivers combined. But it is not on land. It's a river of water vapor in the atmosphere. Atmospheric rivers (ARs) are narrow corridors of water vapor transport in the lower atmosphere that traverse long swaths of the Earth's surface as they bind together the atmospheric water cycle (Figure 1). The characteristic (indeed defining) dimensions of these ARs are (1) integrated water vapor (IWV) concentrations such that if all the vapor in the atmospheric column were condensed into liquid water, the result would be a layer 2 or more centimeters thick; (2) wind speeds of greater than 12.5 meters per second in the lowest 2 kilometers; and (3) a shape that is long and narrow, no more than 400-500 kilometers wide, and extending for thousands of kilometers, sometimes across entire ocean basins.

  8. Flood-inundation maps for the West Branch Susquehanna River near the Boroughs of Lewisburg and Milton, Pennsylvania

    Science.gov (United States)

    Roland, Mark A.; Hoffman, Scott A.

    2014-01-01

    Digital flood-inundation maps for an approximate 8-mile reach of the West Branch Susquehanna River from approximately 2 miles downstream from the Borough of Lewisburg, extending upstream to approximately 1 mile upstream from the Borough of Milton, Pennsylvania, were created by the U.S. Geological Survey (USGS) in cooperation with the Susquehanna River Basin Commission (SRBC). The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict the estimated areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage 01553500, West Branch Susquehanna River at Lewisburg, Pa. In addition, the information has been provided to the Susquehanna River Basin Commission (SRBC) for incorporation into their Susquehanna Inundation Map Viewer (SIMV) flood warning system (http://maps.srbc.net/simv/). The National Weather Service (NWS) forecasted peak-stage information (http://water.weather.gov/ahps) for USGS streamgage 01553500, West Branch Susquehanna River at Lewisburg, Pa., may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. Calibration of the model was achieved using the most current stage-discharge relations (rating number 11.1) at USGS streamgage 01553500, West Branch Susquehanna River at Lewisburg, Pa., a documented water-surface profile from the December 2, 2010, flood, and recorded peak stage data. The hydraulic model was then used to determine 26 water-surface profiles for flood stages at 1-foot intervals referenced to the streamgage datum ranging from 14 feet (ft) to 39 ft. Modeled flood stages, as defined by NWS, include Action Stage, 14 ft; Flood Stage, 18 ft; Moderate Flood Stage, 23 ft; and Major Flood Stage, 28 ft. Geographic information system (GIS) technology

  9. Modelling of tidally affected river reaches with data assimilation for flood warning purposes: An example on the River Dee, UK

    Science.gov (United States)

    Smith, P. J.; Beven, K.; Horsburgh, K.; Cullen, J.

    2012-04-01

    On rivers where the flow regime is influenced by a tidal signal the provision of accurate forecasts requires the careful coupling of predictive models for both the tidal signal and the rainfall driven river system. This paper discusses such a coupled modelling system constructed for the River Dee (UK). A series of parsimonious, physically interpretable time series models are used to represent the dynamics of the river water level at several gauging sites on the flood plain. These gauges are used operationally to help in determining the issuing of flood warnings. The simplified models are coupled and cast into a state space form. The assimilation of the observed water levels at the gauge sites to inform future forecasts is then a non-linear filter a solution to which is readily approximated. Assessment of the model forecasts against the observed data is carried out using a number of existing metrics. These suggest the model forecasts are a useful guide to the future water level. The representation of the forecast and its uncertainty to the operational staff is considered. A prototype of the sequential decision making process; based on the relative cost of 'true' or 'false' warnings; and designed to help guide the catchment manager in issuing warnings is presented.

  10. Effects of extreme floods on macroinvertebrate assemblages in tributaries to the Mohawk River, New York, USA

    Science.gov (United States)

    Calderon, Mirian R.; Baldigo, Barry P.; Smith, Alexander J.; Endreny, Theodore A.

    2017-01-01

    Climate change is forecast to bring more frequent and intense precipitation to New York which has motivated research into the effects of floods on stream ecosystems. Macroinvertebrate assemblages were sampled at 13 sites in the Mohawk River basin during August 2011, and again in October 2011, following historic floods caused by remnants of Hurricane Irene and Tropical Storm Lee. The annual exceedance probabilities of floods at regional flow-monitoring sites ranged from 0.5 to 0.001. Data from the first 2 surveys, and from additional surveys done during July and October 2014, were assessed to characterize the severity of flood impacts, effect of seasonality, and recovery. Indices of total taxa richness; Ephemeroptera, Plecoptera, and Trichoptera (EPT) richness; Hilsenhoff's biotic index; per cent model affinity; and nutrient biotic index-phosphorus were combined to calculate New York State Biological Assessment Profile scores. Analysis of variance tests were used to determine if the Biological Assessment Profile, its component metrics, relative abundance, and diversity differed significantly (p ≤ .05) among the four surveys. Only total taxa richness and Shannon–Wiener diversity increased significantly, and abundance decreased significantly, following the floods. No metrics differed significantly between the July and August 2014 surveys which indicates that the differences denoted between the August and October 2011 surveys were caused by the floods. Changes in taxa richness, EPT richness, and diversity were significantly correlated with flood annual exceedance probabilities. This study increased our understanding of the resistance and resilience of benthic macroinvertebrate communities by showing that their assemblages were relatively impervious to extreme floods across the region.

  11. New river flow maxima in Northern England, December 2015: Implications for flood hazard and risk assessment?

    Science.gov (United States)

    Thornton, James

    2016-04-01

    December 2015 was recently confirmed as the UK's wettest month on record by the Met Office. The most extreme precipitation was associated with three extratropical storm systems, named Desmond, Eva and Frank by the pilot Met Éireann/Met Office "Name our storms" project. In response, river levels reached new maxima at many locations across Northern England. Property damage was widespread, with at least 16,000 homes in England flooded. As with recent predecessors, these events reinvigorated public debate about the extent to which natural weather variability, anthropogenic climate change, increased urbanisation and/or other changes in catchment and river management might be responsible for apparent increases in flood frequency and severity. Change detection and attribution science is required to inform the debate, but is complicated by the short (typically ~ 35 years) river flow records available. Running a large number of coupled climate and hydrological model simulations is a powerful way of addressing the 'attribution question' with respect to the hypothesised climate forcing, for example, albeit one that remains largely in the research domain at present. In the meantime, flood-frequency analysis of available records still forms the bedrock of practice in the water industry; the results are used routinely in the design of new defence structures and in the development of flood hazard maps, amongst other things. In such analyses, it is usual for the records to be assumed stationary. In this context, the specific aims of this research are twofold: • To investigate whether, under the assumption of stationarity, the outputs of standard flood-frequency modelling methods (both 'single-site' and 'spatially pooled' methods) differ significantly depending on whether the new peaks are included or excluded, and; • To assess the sustainability of previous conclusions regarding trends in English river flows by reapplying simple statistical tests, such as the Mann-Kendal test

  12. An analysis of changes in flood quantiles at the gauge Neu Darchau (Elbe River) from 1875 to 2013

    Science.gov (United States)

    Mudersbach, Christoph; Bender, Jens; Netzel, Fabian

    2016-05-01

    Within this investigation, we focus on a detailed analysis of the discharge data of the gauge Neu Darchau (Elbe River). The Elbe River inflows onto the North Sea. The gauge Neu Darchau is the most downstream discharge gauge of the Elbe River before it becomes an estuary. We follow the questions, whether the discharge characteristics of the Elbe River have changed over the last decades and how much common flood quantiles (i.e. 100-year flood) are affected by the latest extreme events in 2002, 2006, 2011, and 2013. Hence, we conduct (i) trend and seasonality analysis and (ii) an assessment of time-dependencies of flood quantiles by using quasi non-stationary extreme value statistics with both block maxima and peak-over-threshold approaches. The (iii) significance of the changes found in flood quantiles are assessed by using a stochastic approach based on autoregressive models and Monte Carlo simulations. The results of the trend analyses do show no clear evidences for any significant trends in daily mean discharges and increasing flood frequencies. With respect to the extreme events in 2002, 2006, 2011, and 2013 our results reveal, that those events do not lead to extraordinary changes in the 100-year floods. Nevertheless, in the majority an increase in the 100-year floods over the recent decades can be stated. Although these changes are not significant, for many time series of the 100-year flood quantiles there is a clear tendency towards the upper confidence band.

  13. Towards sustainable flood risk management in the Rhine and Meuse river basins: synopsis of the findings of IRMA-SPONGE

    NARCIS (Netherlands)

    Hooijer, A.; Klijn, F.; Pedroli, G.B.M.; Os, van A.G.

    2004-01-01

    Recent flood events in western Europe have shown the need for improved flood risk management along the Rhine and Meuse rivers. In response, the IRMA-SPONGE research programme was established, consisting of 13 research projects, in which over 30 organizations from six countries co-operated. The aim o

  14. Elbe river flood peaks and postwar agricultural land use in East Germany.

    Science.gov (United States)

    van der Ploeg, R R; Schweigert, P

    2001-12-01

    Collectivization of farmland since the 1950s has changed the agricultural land use in former East Germany. Single fields on the collective farms became increasingly large and were cultivated with increasingly heavy farm equipment. This led to large-scale physical degradation of arable soils, enhancing the formation of surface runoff in periods with prolonged and excessive precipitation. The extent to which this development may have affected the discharge behavior of the main East German river, the Elbe, has so far not been studied. We analyzed the flood peaks of the Elbe during the past century (1900-2000). The flood discharge behavior of the Elbe has apparently changed significantly since the 1950s. Although climate changes may be involved, we conclude that the Elbe flood peaks, recorded since 1950, are related to the changes in postwar agricultural land use in former East Germany. To restore the degraded farmland soils, a change in agricultural land use may be necessary.

  15. 33 CFR 203.48 - Inspection guidelines for non-Federal flood control works.

    Science.gov (United States)

    2010-07-01

    ...-Federal flood control works. 203.48 Section 203.48 Navigation and Navigable Waters CORPS OF ENGINEERS... DISASTER PROCEDURES Rehabilitation Assistance for Flood Control Works Damaged by Flood or Coastal Storm..., construction, and maintenance of non-Federal flood control works. The guidelines are not intended to...

  16. 33 CFR 203.50 - Nonstructural alternatives to rehabilitation of flood control works.

    Science.gov (United States)

    2010-07-01

    ... rehabilitation of flood control works. 203.50 Section 203.50 Navigation and Navigable Waters CORPS OF ENGINEERS... DISASTER PROCEDURES Rehabilitation Assistance for Flood Control Works Damaged by Flood or Coastal Storm... of flood control works. (a) Authority. Under Public Law 84-99, the Chief of Engineers is...

  17. 33 CFR 203.42 - Inspection of non-Federal flood control works.

    Science.gov (United States)

    2010-07-01

    ... PROCEDURES Rehabilitation Assistance for Flood Control Works Damaged by Flood or Coastal Storm: The Corps Rehabilitation and Inspection Program § 203.42 Inspection of non-Federal flood control works. (a) Required inspections. The Corps will conduct inspections of non-Federal flood control works. These inspections are...

  18. 33 CFR 203.45 - Rehabilitation of Federal flood control works.

    Science.gov (United States)

    2010-07-01

    ... PROCEDURES Rehabilitation Assistance for Flood Control Works Damaged by Flood or Coastal Storm: The Corps Rehabilitation and Inspection Program § 203.45 Rehabilitation of Federal flood control works. Rehabilitation of Federal flood control projects will be identical to rehabilitation of non-Federal projects (§...

  19. 33 CFR 203.43 - Inspection of Federal flood control works.

    Science.gov (United States)

    2010-07-01

    ... PROCEDURES Rehabilitation Assistance for Flood Control Works Damaged by Flood or Coastal Storm: The Corps Rehabilitation and Inspection Program § 203.43 Inspection of Federal flood control works. (a) Required inspections. A completed Federal flood control project, or completed functional portions thereof, is...

  20. Predictive Methods for Real-Time Control of Flood Operation of a Multireservoir System: Methodology and Comparative Study

    Science.gov (United States)

    Niewiadomska-Szynkiewicz, Ewa; Malinowski, Krzysztof; Karbowski, Andrzej

    1996-04-01

    Predictive methods for real-time flood operation of water systems consisting of reservoirs located in parallel on tributaries to the main river are presented and discussed. The aspect of conflicting individual goals of the local decision units and other objectives important from an overall point of view is taken into account. The particular attention is focused on hierarchical control structure which provides framework for organization of an on-line reservoir management problem. The important factor involved in flood control the uncertainty with respect to future inflows is taken into consideration. A case study of the upper Vistula river basin system in the southern part of Poland is presented. Simulation results based on 11 historical floods are briefly described and discussed.

  1. Monitoring Niger River Floods from satellite Rainfall Estimates : overall skill and rainfall uncertainty propagation.

    Science.gov (United States)

    Gosset, Marielle; Casse, Claire; Peugeot, christophe; boone, aaron; pedinotti, vanessa

    2015-04-01

    Global measurement of rainfall offers new opportunity for hydrological monitoring, especially for some of the largest Tropical river where the rain gauge network is sparse and radar is not available. Member of the GPM constellation, the new French-Indian satellite Mission Megha-Tropiques (MT) dedicated to the water and energy budget in the tropical atmosphere contributes to a better monitoring of rainfall in the inter-tropical zone. As part of this mission, research is developed on the use of satellite rainfall products for hydrological research or operational application such as flood monitoring. A key issue for such applications is how to account for rainfall products biases and uncertainties, and how to propagate them into the end user models ? Another important question is how to choose the best space-time resolution for the rainfall forcing, given that both model performances and rain-product uncertainties are resolution dependent. This paper analyses the potential of satellite rainfall products combined with hydrological modeling to monitor the Niger river floods in the city of Niamey, Niger. A dramatic increase of these floods has been observed in the last decades. The study focuses on the 125000 km2 area in the vicinity of Niamey, where local runoff is responsible for the most extreme floods recorded in recent years. Several rainfall products are tested as forcing to the SURFEX-TRIP hydrological simulations. Differences in terms of rainfall amount, number of rainy days, spatial extension of the rainfall events and frequency distribution of the rain rates are found among the products. Their impacts on the simulated outflow is analyzed. The simulations based on the Real time estimates produce an excess in the discharge. For flood prediction, the problem can be overcome by a prior adjustment of the products - as done here with probability matching - or by analysing the simulated discharge in terms of percentile or anomaly. All tested products exhibit some

  2. The ordered network structure and its prediction for the big floods of the Changjiang River Basins

    Energy Technology Data Exchange (ETDEWEB)

    Men, Ke-Pei; Zhao, Kai; Zhu, Shu-Dan [Nanjing Univ. of Information Science and Technology, Nanjing (China). College of Mathematics and Statistics

    2013-12-15

    According to the latest statistical data of hydrology, a total of 21 floods took place over the Changjiang (Yangtze) River Basins from 1827 to 2012 and showed an obvious commensurable orderliness. In the guidance of the information forecasting theory of Wen-Bo Weng, based on previous research results, combining ordered analysis with complex network technology, we focus on the summary of the ordered network structure of the Changjiang floods, supplement new information, further optimize networks, construct the 2D- and 3D-ordered network structure and make prediction research. Predictions show that the future big deluges will probably occur over the Changjiang River Basin around 2013-2014, 2020-2021, 2030, 2036, 2051, and 2058. (orig.)

  3. Quantification of Multiple Climate Change and Human Activity Impact Factors on Flood Regimes in the Pearl River Delta of China

    Directory of Open Access Journals (Sweden)

    Yihan Tang

    2016-01-01

    Full Text Available Coastal flood regimes have been irreversibly altered by both climate change and human activities. This paper aims to quantify the impacts of multiple factors on delta flood. The Pearl River Delta (PRD, with dense river network and population, is one of the most developed coastal areas in China. The recorded extreme water level (m.s.l. in flood season has been heavily interfered with by varied income flood flow, sea-level rise, and dredged riverbeds. A methodology, composed of a numerical model and the index R, has been developed to quantify the impacts of these driving factors in the the PRD. Results show that the flood level varied 4.29%–53.49% from the change of fluvial discharge, 3.35%–38.73% from riverbed dredging, and 0.12%–16.81% from sea-level rise. The variation of flood flow apparently takes the most effect and sea-level rise the least. In particular, dense river network intensifies the impact of income flood change and sea-level rise. Findings from this study help understand the causes of the the PRD flood regimes and provide theoretical support for flood protection in the delta region.

  4. SIGNIFICANT FLOODS ON THE UPPER TISZA/TISA AND ALONG THE LOWER SZAMOS/SOMEŞ RIVER (FROM 1876 ONWARDS

    Directory of Open Access Journals (Sweden)

    K. KONECSNY

    2016-03-01

    Full Text Available Dealing with floodwave propagationon rivers, as well as flooding related phenomena, planning of engineering works to moderate the dangers of flooding, dealing with flood hazard and risk, necessitates the knowledge of the affected rivers in terms of historical hydrological regime, hydrological patterns and specifically of data pertaining to significant flood events and their consequences. Several of the older but alsothe more recent scholarly articles about the left side tributaries of the Tisa river published incomplete or false figures about the major flood events of the period covered by systematic hydrometric flow records. The afore mentioned issues inspired the collation and analysis of data published in Hungarian and Romanian hydrological yearbooks and the relevant professional publications and the creation of a flood chronology. The continuous and reliable hydrometric data collection on the basin of the Upper Tisa and the lower Someş basin goes back to 1876 the publication of the first Hungarian hydrological yearbook. Based on this information we have highlighted the significant flood events, charted their occurance patterns, and the changes of the flood trends. We discussed the pecularities of the greatest flood waves and their consequences in greater detail.

  5. Revising time series of the Elbe river discharge for flood frequency determination at gauge Dresden

    OpenAIRE

    Bartl, S; S. Schümberg; Deutsch, M

    2009-01-01

    The German research programme RIsk MAnagment of eXtreme flood events has accomplished the improvement of regional hazard assessment for the large rivers in Germany. Here we focused on the Elbe river at its gauge Dresden, which belongs to the oldest gauges in Europe with officially available daily discharge time series beginning on 1 January 1890. The project on the one hand aimed to extend and to revise the existing time series, and on the other hand to examine the variability of the Elbe riv...

  6. BED VARIATION ANALYSIS IN THE CHIKUGO RIVER ESTUARY BY THE FLOOD FLOWS

    Science.gov (United States)

    Suzuki, Kenta; Shimamoto, Hisanori; Kubo, Seiki; Fukuoka, Shoji

    A series of fisherie issues in the Ariake sea has been believed to be caused by a lack of sand supply from the Chikugo river on the basis of few investigations of characteristics and amount of sediment transport in the the Chikugo river estuary. The core sampling and super-sonic echo sounder indicates that the vertical structure of mid stream of the Chikugo river estuary is consists of complex alternate layer and the rate of water content is much different to each layer. To make the rate of sand transport in the Chikugo river estuary clear, the authors applied unsteady quasi-three dimensional flood flow and river bed variation analysis using observed temporal changes in water surface profiles of flood. In the analysis, the bed layer which the rate of water content upper than 70% is calculated 2009by the experimental equation of erosion speed of the cohesive material. The results of analysis indicates that the rate of sand supply is strongly affected by the tidal level change of the Ariake sea.

  7. Revising time series of the Elbe river discharge for flood frequency determination at gauge Dresden

    Directory of Open Access Journals (Sweden)

    S. Bartl

    2009-11-01

    Full Text Available The German research programme RIsk MAnagment of eXtreme flood events has accomplished the improvement of regional hazard assessment for the large rivers in Germany. Here we focused on the Elbe river at its gauge Dresden, which belongs to the oldest gauges in Europe with officially available daily discharge time series beginning on 1 January 1890. The project on the one hand aimed to extend and to revise the existing time series, and on the other hand to examine the variability of the Elbe river discharge conditions on a greater time scale. Therefore one major task were the historical searches and the examination of the retrieved documents and the contained information. After analysing this information the development of the river course and the discharge conditions were discussed. Using the provided knowledge, in an other subproject, a historical hydraulic model was established. Its results then again were used here. A further purpose was the determining of flood frequency based on all pre-processed data. The obtained knowledge about historical changes was also used to get an idea about possible future variations under climate change conditions. Especially variations in the runoff characteristic of the Elbe river over the course of the year were analysed. It succeeded to obtain a much longer discharge time series which contain fewer errors and uncertainties. Hence an optimized regional hazard assessment was realised.

  8. Relationship of Rainfall Distribution and Water Level on Major Flood 2014 in Pahang River Basin, Malaysia

    Directory of Open Access Journals (Sweden)

    Nur Hishaam Sulaiman

    2017-01-01

    Full Text Available Climate change gives impact on extreme hydrological events especially in extreme rainfall. This article discusses about the relationship of rainfall distribution and water level on major flood 2014 in Pahang River Basin, Malaysia in helping decision makers to flood management system. Based on DID Malaysia rainfall station, 56 stations have being use as point in this research and it is including Pahang, Terengganu, Kelantan and Perak. Data set for this study were analysed with GIS analysis using interpolation method to develop Isohyet map and XLstat statistical software for PCA and SPC analyses. The results that were obtained from the Isohyet Map for three months was mid-November, rainfall started to increase about in range of 800mm-1200mm and the intensity keep increased to 2200mm at mid-December 2014. The high rainfall intensity sense at highland that is upstream of Pahang River. The PCA and SPC analysis also indicates the high relationship between rainfall and water level of few places at Pahang River. The Sg. Yap station and Kg. Serambi station obtained the high relationship of rainfall and water level with factor loading value at 0.9330 and 0.9051 for each station. Hydrological pattern and trend are extremely affected by climate such as north east monsoon season that occurred in South China Sea and affected Pahang during November to March. The findings of this study are important to local authorities by providing basic data as guidelines to the integrated river management at Pahang River Basin.

  9. A statistical forecast model for Tropical Cyclone Rainfall and flood events for the Hudson River

    Science.gov (United States)

    Cioffi, Francesco; Conticello, Federico; Hall, Thimoty; Lall, Upmanu; Orton, Philip

    2014-05-01

    Tropical Cyclones (TCs) lead to potentially severe coastal flooding through wind surge and also through rainfall-runoff processes. There is growing interest in modeling these processes simultaneously. Here, a statistical approach that can facilitate this process is presented with an application to the Hudson River Basin that is associated with the New York City metropolitan area. Three submodels are used in sequence. The first submodel is a stochastic model of the complete life cycle of North Atlantic (NA) tropical cyclones developed by Hall and Yonekura (2011). It uses archived data of TCs throughout the North Atlantic to estimate landfall rates at high geographic resolution as a function of the ENSO state and of sea surface temperature (SST). The second submodel translates the attributes of a tropical cyclone simulated by the first model to rainfall intensity at selected stations within the watershed of Hudson River. Two different approaches are used and compared: artificial neural network (ANN) and k-nearest neighbor (KNN). Finally, the third submodel transforms, once again, by using an ANN approach and KNN, the rainfall intensities, calculated for the ensemble of the stations, to the streamflows at specific points of the tributaries of the Hudson River. These streamflows are to be used as inputs in a hydrodynamic model that includes storm surge surge dynamics for the simulation of coastal flooding along the Hudson River. Calibration and validation of the model is carried out by using, selected tropical cyclone data since 1950, and hourly station rainfall and streamflow recorded for such extreme events. Four stream gauges (Troy dam, Mohawk River at Cohoes, Mohawk River diversion at Crescent Dam, Hudson River above lock one nr Waterford), a gauge from a tributary in the lower Hudson River, and over 20 rain gauges are used. The performance of the proposed model as tool for storm events is then analyzed and discussed.

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

    Science.gov (United States)

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

    2012-01-01

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

  11. Validation of a social vulnerability index in context to river-floods in Germany

    Directory of Open Access Journals (Sweden)

    A. Fekete

    2009-03-01

    Full Text Available Social vulnerability indices are a means for generating information about people potentially affected by disasters that are e.g. triggered by river-floods. The purpose behind such an index is in this study the development and the validation of a social vulnerability map of population characteristics towards river-floods covering all counties in Germany. This map is based on a composite index of three main indicators for social vulnerability in Germany – fragility, socio-economic conditions and region. These indicators have been identified by a factor analysis of selected demographic variables obtained from federal statistical offices. Therefore, these indicators can be updated annually based on a reliable data source. The vulnerability patterns detected by the factor analysis are verified by using an independent second data set. The interpretation of the second data set shows that vulnerability is revealed by a real extreme flood event and demonstrates that the patterns of the presumed vulnerability match the observations of a real event. It comprises a survey of flood-affected households in three federal states. By using logistic regression, it is demonstrated that the theoretically presumed indications of vulnerability are correct and that the indicators are valid. It is shown that indeed certain social groups like the elderly, the financially weak or the urban residents are higher risk groups.

  12. Forensic Hydrological Investigation of the Blanco River Flood May 2015, Wimberley, TX

    Science.gov (United States)

    Furl, C.

    2015-12-01

    A forensic hydrological investigation of a major flash flood was conducted for the Blanco River in south-central Texas. The unprecedented flood occurred during the early morning hours of May 24th leaving 12 dead in the towns of Wimberley and San Marcos. Hundreds of homes were damaged or destroyed, two reinforced concrete bridges were washed off their piers, and nearly 100 high water rescues were made the following day. The present work characterizes the meteorological setup leading to the event, describes the flood hydrology using the Gridded Surface Subsurface Hydrologic Analysis (GSSHA) model, and reports on an extensive field campaign seeking to document high water marks throughout the 1200 km2 basin. Results indicate high precipitable water values, large CAPE, and strong mid and upper level winds aided in impressive divergence over the region. This allowed for storms to continually produce heavy rainfall over the same areas. Large regions of the catchment received greater than 200 mm across the upper portion of the basin with 24 hr maximums around 330 mm. GSSHA simulations indicate good performance when compared to a stage hydrograph recorded mid-catchment. The remaining USGS gauges failed early on during the rising limb of the hydrograph. Model estimates indicate peak streamflow was approximately 5500 cms with stage values nearing 13 m as the flood wave moved through the town of Wimberley. Approximately 125 locations were examined for high water marks along the mainstem of the river using RTK GPS. Stage values ranged from 12 - 18 m.

  13. An elusive search for regional flood frequency estimates in the River Nile basin

    Directory of Open Access Journals (Sweden)

    P. Nyeko-Ogiramoi

    2012-09-01

    Full Text Available Estimation of peak flow quantiles in ungauged catchments is a challenge often faced by water professionals in many parts of the world. Approaches to address such problem exist, but widely used techniques such as flood frequency regionalisation is often not subjected to performance evaluation. In this study, the jack-knifing principle is used to assess the performance of the flood frequency regionalisation in the complex and data-scarce River Nile basin by examining the error (regionalisation error between locally and regionally estimated peak flow quantiles for different return periods (QT. Agglomerative hierarchical clustering based algorithms were used to search for regions with similar hydrological characteristics. Hydrological data employed were from 180 gauged catchments and several physical characteristics in order to regionalise 365 identified catchments. The Generalised Extreme Value (GEV distribution, selected using L-moment based approach, was used to construct regional growth curves from which peak flow growth factors could be derived and mapped through interpolation. Inside each region, variations in at-site flood frequency distribution were modelled by regression of the mean annual maximum peak flow (MAF versus catchment area. The results showed that the performance of the regionalisation is heavily dependent on the historical flow record length and the similarity of the hydrological characteristics inside the regions. The flood frequency regionalisation of the River Nile basin can be improved if sufficient flow data of longer record length of at least 40 yr become available.

  14. Production and decomposition of forest litter fall on the Apalachicola River flood plain, Florida

    Science.gov (United States)

    Elder, J.F.; Cairns, D.J.

    1982-01-01

    Measurements of litter fall (leaves and other particulate organic material) and leaf decomposition were made on the Apalachicola River flood plain in 1979-80. Litter fall was collected monthly in five different forest types in swamp and levee areas. Leaves from 42 species of trees and other plants accounted for 58 percent of total litter fall. The remaining 42 percent was nonleaf material. Average litter fall was 800 grams per square meter per year in the flood plain. Tupelo (Nyssa), baldcypress (Taxodium), and ash (Fraxinus), all swamp-adapted trees, produce over 50 percent of the leaf fall. Common levee species such as sweetgum (Liquidambar styraciflua) and diamond-leaf oak (Quercus laurifolia) are also major contributors to total flood-plain litter fall. Annual flooding of the river provides an important mechanism for mobilization of the litter-fall products. Leaf decomposition rates were greatly reduced in dry environments. Carbon loss was nearly linear over a 6-month period, but nitrogen and phosphorus loss was exponential and nearly complete within 1 month. (USGS)

  15. Hydraulic conditions of flood flows in a Polish Carpathian river subjected to variable human impacts

    Science.gov (United States)

    Radecki-Pawlik, Artur; Czech, Wiktoria; Wyżga, Bartłomiej; Mikuś, Paweł; Zawiejska, Joanna; Ruiz-Villanueva, Virginia

    2016-04-01

    Channel morphology of the Czarny Dunajec River, Polish Carpathians, has been considerably modified as a result of channelization and gravel-mining induced channel incision, and now it varies from a single-thread, incised or regulated channel to an unmanaged, multi-thread channel. We investigated effects of these distinct channel morphologies on the conditions for flood flows in a study of 25 cross-sections from the middle river course where the Czarny Dunajec receives no significant tributaries and flood discharges increase little in the downstream direction. Cross-sectional morphology, channel slope and roughness of particular cross-section parts were used as input data for the hydraulic modelling performed with the 1D steady-flow HEC-RAS model for discharges with recurrence interval from 1.5 to 50 years. The model for each cross-section was calibrated with the water level of a 20-year flood from May 2014, determined shortly after the flood on the basis of high-water marks. Results indicated that incised and channelized river reaches are typified by similar flow widths and cross-sectional flow areas, which are substantially smaller than those in the multi-thread reach. However, because of steeper channel slope in the incised reach than in the channelized reach, the three river reaches differ in unit stream power and bed shear stress, which attain the highest values in the incised reach, intermediate values in the channelized reach, and the lowest ones in the multi-thread reach. These patterns of flow power and hydraulic forces are reflected in significant differences in river competence between the three river reaches. Since the introduction of the channelization scheme 30 years ago, sedimentation has reduced its initial flow conveyance by more than half and elevated water stages at given flood discharges by about 0.5-0.7 m. This partly reflects a progressive growth of natural levees along artificially stabilized channel banks. By contrast, sediments of natural

  16. A methodological approach to rapid assessment of a river flood in coastal waters. First test in the Po River delta

    Science.gov (United States)

    Campanelli, Alessandra; Bellafiore, Debora; Bensi, Manuel; Bignami, Francesco; Caccamo, Giuseppe; Celussi, Mauro; Del Negro, Paola; Ferrarin, Christian; Marini, Mauro; Paschini, Elio; Zaggia, Luca

    2014-05-01

    As part of the actions of the flagship project RITMARE (Ricerca ITaliana per il MARE) a daily oceanographic survey was performed on 29th November 2013 in front of the Po River delta (Northern Adriatic Sea). The Po river affects a large part of the Northern Adriatic Sea with strong implications on the circulation and functionality of the basin. Physical-chemical and biological properties of coastal waters were investigated after a moderate flood occurred around 25th-27th November. The cruise activities, carried out using a small research boat, were mainly focused on the test of a methodological approach to investigate the environment variability after a flood event in the framework of rapid assessment. The effects of the flood on the coastal waters, have been evaluated in the field using operational forecasts and real-time satellite imagery to assist field measurements and samplings. Surface satellite chlorophyll maps and surface salinity and current maps obtained from a numerical model forced by meteorological forecast and river data were analyzed to better identify the Po plume dispersion during and after the event in order to better locate offshore monitoring stations at the sea. Profiles of Temperature, Salinity, Turbidity, Fluorescence and Colored Dissolved Organic Matter (CDOM) throughout the water column were collected at 7 stations in front of the Po River delta. Sea surface water samples were also collected for the analysis of nutrients, Dissolved Organic Carbon (DOC) and CDOM (surface and bottom). The CDOM regulates the penetration of UV light throughout the water column and mediates photochemical reactions, playing an important role in many marine biogeochemical processes. Satellite images showed a strong color front that separates the higher-chlorophyll coastal water from the more oligotrophic mid-basin and eastern boundary Adriatic waters. In front of the river mouth, the surface layer was characterized by low salinity (14-15), high turbidity (8-11 NTU

  17. Copula-Based Bivariate Flood Frequency Analysis in a Changing Climate-A Case Study in the Huai River Basin, China

    Institute of Scientific and Technical Information of China (English)

    Kai Duan; Yadong Mei; Liping Zhang

    2016-01-01

    ABSTRACT:Copula-based bivariate frequency analysis can be used to investigate the changes in flood characteristics in the Huai River Basin that could be caused by climate change. The univariate distribu-tions of historical flood peak, maximum 3-day and 7-day volumes in 1961–2000 and future values in 2061–2100 projected from two GCMs (CSIRO-MK3.5 and CCCma-CGCM3.1) under A2, A1B and B1 emission scenarios are analyzed and compared. Then, bivariate distributions of peaks and volumes are constructed based on the copula method and possible changes in joint return periods are characterized. Results indicate that the Clayton copula is more appropriate for historical and CCCma-CGCM3.1 simu-lating flood variables, while that of Frank and Gumbel are better fitted to CSIRO-MK3.5 simulations. The variations of univariate and bivariate return periods reveal that flood characteristics may be more sensi-tive to different GCMs than different emission scenarios. Between the two GCMs, CSIRO-MK3.5 evi-dently predicts much more severe flood conditions in future, especially under B1 scenario, whereas CCCma-CGCM3.1 generally suggests contrary changing signals. This study corroborates that copulas can serve as a viable and flexible tool to connect univariate marginal distributions of flood variables and quantify the associated risks, which may provide useful information for risk-based flood control.

  18. MODELING DAM-BREAK FLOOD OVER NATURAL RIVERS USING DISCONTINUOUS GALERKIN METHOD

    Institute of Scientific and Technical Information of China (English)

    LAI Wencong; KHAN Abdul A.

    2012-01-01

    A well-balanced numerical model is presented for two-dimensional,depth-averaged,shallow water flows based on the Discontinuous Galerkin (DG) method.The model is applied to simulate dam-brcak flood in natural rivers with wet/dry bed and complex topography.To eliminate numerical imbalance,the pressure force and bed slope terms are combined in the shallow water flow equations.For partially wet/dry elements,a treatment of the source term that preserves the well-balanced property is presented.A treatment for modeling flow over initially dry bed is presented.Numerical results show that the time step used is related to the dry bed criterion.The intercell numerical flux in the DG method is computed by the Harten-Lax-van Contact (HLLC) approximate Riemann solver.A two-dimensional slope limiting procedure is employed to prevent spurious oscillation.The robustness and accuracy of the model are demonstrated through several test cases,including dam-break flow in a channel with three bumps,laboratory dam-break tests over a triangular bump and an L-shape bend,dam-break flood in the Paute River,and the Malpasset dam-break case.Numerical results show that the model is robust and accurate to simulate dam-break flood over natural rivers with complex geometry and wet/dry beds.

  19. Interannual kinetics (2010-2013) of large wood in a river corridor exposed to a 50-year flood event and fluvial ice dynamics

    Science.gov (United States)

    Boivin, Maxime; Buffin-Bélanger, Thomas; Piégay, Hervé

    2017-02-01

    Semi-alluvial rivers of the Gaspé Peninsula, Québec, are prone to produce and transport vast quantities of large wood (LW). The high rate of lateral erosion owing to high energy flows and noncohesive banks is the main process leading to the recruitment of large wood, which in turn initiates complex patterns of wood accumulation and reentrainment within the active channel. The delta of the Saint-Jean River (SJR) has accumulated large annual wood fluxes since 1960 that culminated in a wood raft of > 3-km in length in 2014. To document the kinetics of large wood on the main channel of SJR, four annual surveys were carried out from 2010 to 2013 to locate and describe > 1000 large wood jams (LWJ) and 2000 large wood individuals (LWI) along a 60-km river section. Airborne and ground photo/video images were used to estimate the wood volume introduced by lateral erosion and to identify local geomorphic conditions that control wood mobility and deposits. Video camera analysis allowed the examination of transport rates from three hydrometeorological events for specific river sections. Results indicate that the volume of LW recruited between 2010 and 2013 represents 57% of the total LW production over the 2004-2013 period. Volumes of wood deposited along the 60-km section were four times higher in 2013 than in 2010. Increases in wood amount occurred mainly in upper alluvial sections of the river, whereas decreases were observed in the semi-alluvial middle sections. Observations suggest that the 50-year flood event of 2010 produced large amounts of LW that were only partly exported out of the basin so that a significant amount was still available for subsequent floods. Large wood storage continued after this flood until a similar flood or an ice-breakup event could remobilise these LW accumulations into the river corridor. Ice-jam floods transport large amounts of wood during events with fairly low flow but do not contribute significantly to recruitment rates (ca. 10 to 30

  20. Estimation of the Probable Maximum Flood for a Small Lowland River in Poland

    Science.gov (United States)

    Banasik, K.; Hejduk, L.

    2009-04-01

    The planning, designe and use of hydrotechnical structures often requires the assesment of maximu flood potentials. The most common term applied to this upper limit of flooding is the probable maximum flood (PMF). The PMP/UH (probable maximum precipitation/unit hydrograph) method has been used in the study to predict PMF from a small agricultural lowland river basin of Zagozdzonka (left tributary of Vistula river) in Poland. The river basin, located about 100 km south of Warsaw, with an area - upstream the gauge of Plachty - of 82 km2, has been investigated by Department of Water Engineering and Environmenal Restoration of Warsaw University of Life Sciences - SGGW since 1962. Over 40-year flow record was used in previous investigation for predicting T-year flood discharge (Banasik et al., 2003). The objective here was to estimate the PMF using the PMP/UH method and to compare the results with the 100-year flood. A new relation of depth-duration curve of PMP for the local climatic condition has been developed based on Polish maximum observed rainfall data (Ozga-Zielinska & Ozga-Zielinski, 2003). Exponential formula, with the value of exponent of 0.47, i.e. close to the exponent in formula for world PMP and also in the formula of PMP for Great Britain (Wilson, 1993), gives the rainfall depth about 40% lower than the Wilson's one. The effective rainfall (runoff volume) has been estimated from the PMP of various duration using the CN-method (USDA-SCS, 1986). The CN value as well as parameters of the IUH model (Nash, 1957) have been established from the 27 rainfall-runoff events, recorded in the river basin in the period 1980-2004. Varibility of the parameter values with the size of the events will be discussed in the paper. The results of the analyse have shown that the peak discharge of the PMF is 4.5 times larger then 100-year flood, and volume ratio of the respective direct hydrographs caused by rainfall events of critical duration is 4.0. References 1.Banasik K

  1. Comparative Study of Flood Risk Management and Land Use in the Deltas of Rhine River, Yellow River and Mississippi River

    NARCIS (Netherlands)

    Huang B; Guangzhou, M.

    2007-01-01

    The Rhine River in the Netherlands, the Yellow River in China and the Mississippi River in the U.S. are three great rivers in the world. Each of them is performing a significant role in the country. The delta area for each river, in particular, is served as the centre in importance and commonly the

  2. Comparative Study of Flood Risk Management and Land Use in the Deltas of Rhine River, Yellow River and Mississippi River

    NARCIS (Netherlands)

    Huang B; Guangzhou, M.

    2007-01-01

    The Rhine River in the Netherlands, the Yellow River in China and the Mississippi River in the U.S. are three great rivers in the world. Each of them is performing a significant role in the country. The delta area for each river, in particular, is served as the centre in importance and commonly the

  3. Flood monitoring for ungauged rivers: the power of combining space-based monitoring and global forecasting models

    Science.gov (United States)

    Revilla-Romero, Beatriz; Netgeka, Victor; Raynaud, Damien; Thielen, Jutta

    2013-04-01

    Flood warning systems typically rely on forecasts from national meteorological services and in-situ observations from hydrological gauging stations. This capacity is not equally developed in flood-prone developing countries. Low-cost satellite monitoring systems and global flood forecasting systems can be an alternative source of information for national flood authorities. The Global Flood Awareness System (GloFAS) has been develop jointly with the European Centre for Medium-Range Weather Forecast (ECMWF) and the Joint Research Centre, and it is running quasi operational now since June 2011. The system couples state-of-the art weather forecasts with a hydrological model driven at a continental scale. The system provides downstream countries with information on upstream river conditions as well as continental and global overviews. In its test phase, this global forecast system provides probabilities for large transnational river flooding at the global scale up to 30 days in advance. It has shown its real-life potential for the first time during the flood in Southeast Asia in 2011, and more recently during the floods in Australia in March 2012, India (Assam, September-October 2012) and Chad Floods (August-October 2012).The Joint Research Centre is working on further research and development, rigorous testing and adaptations of the system to create an operational tool for decision makers, including national and regional water authorities, water resource managers, hydropower companies, civil protection and first line responders, and international humanitarian aid organizations. Currently efforts are being made to link GloFAS to