Spatial diversion and coordination of flood water for an urban flood control project in Suzhou, China

Suzhou City,located in the Yangtze River Delta in China,is prone to flooding due to a complex combination of natural factors,including its monsoon climate,low elevation,and tidally influenced position,as well as intensive human activities.The Large Encirclement Flood Control Project(LEFCP)was launched to cope with serious floods in the urban area.This project changed the spatiotemporal pattern of flood processes and caused spatial diversion of floods from the urban area to the outskirts of the city.Therefore,this study developed a distributed flood simulation model in order to understand this transition of flood processes.The results revealed that the LEFCP effectively protected the urban areas from floods,but the present scheduling schemes resulted in the spatial diversion of floods to the outskirts of the city.With rainstorm frequencies of 10.0%to 0.5%,the water level differences between two representative water level stations(Miduqiao(MDQ)and Fengqiao(FQ))located inside and outside the LEFCP area,ranged from 0.75 m to 0.24 m and from 1.80 m to 1.58 m,respectively.In addition,the flood safety margin at MDQ and the duration with the water level exceeding the warning water level at FQ ranged from 0.95 m to 0.43 m and from 4 h to 22 h,respectively.Rational scheduling schemes for the hydraulic facilities of the LEFCP in extreme precipitation cases were developed ac-cording to food simulations under seven scheduling scenarios.This helps to regulate the spatial flood diversion caused by the LEFCP during extreme precipitation.

Exploration of Sponge System Design in Wetland Parks Based on Rainwater and Flood Control: A Case Study of Southern Anhui Province

Based on the background that wetland resources in China are under threat and urgently need to be protected,a series of rainwater and flood problems caused by urban construction is analyzed comprehensively,and the design and planning methods of wetland parks in response to rainwater and flood disasters caused by floods and heavy rainfall are explored.Southern Anhui with complex and variable terrain and frequent rainfall and flood disasters is selected as the research area,with Xuanzhou District of Xuancheng City as the main research object.The relationship between municipal drainage of urban park and water conservancy drainage is investigated from different sample selection,design samples,and design flow rates.Based on literature review and model building methods,an urban storm flood model suitable for typical wetland parks in southern Anhui is constructed after processing the survey data using Arc GIS,SWMM(storm water management model).On this basis,a methodology and principles for designing a sponge system of wetland park based on rainwater and flood control are proposed,including technical measures such as rainwater collection,retention,and purification.This paper provides certain research results in design schemes,effect evaluations,ecological and social benefits,and useful suggestions and solutions for urban stormwater management and resilience development.

Application of Computer Simulation in the Reservoir Flood Control

[Objective] To discuss the application of simulation technique in preliminary solution of reservoir flood control of.[Method] Based on the study of river system simulation theory,the InfoWorks RS system was adopted to build a digital analog model for flood routing in certain river system and the flood discharge was analyzed with the check criterion.[Result] The flood information system based on InfoWorks RS simulated the inundation of downstream during flood discharge and drew mutation pictures to indicate how hydraulic parameters of maximum runoff at each control section,runoff of each control section and flow velocity varied with time,how hydraulic elements mutated with time as well as the most likely inundated area analysis of lower reservoir.[Conclusion] To provide references for reducing serious loss caused by flood and making out preliminary solution to flood control.

Using modified Soil Conservation Service curve number method to simulate the role of forest in flood control in the upper reach of the Tingjiang River in China

To improve flood control efficiency and increase urban resilience to flooding,the impacts of forest type change on flood control in the upper reach of the Tingjiang River(URTR) were evaluated by a modified model based on the Soil Conservation Service curve number(SCS-CN) method. Parameters of the model were selected and determined according to the comprehensive analysis of model evaluation indexes. The first simulation of forest reconstruction scenario,namely a coniferous forest covering 59.35km^2 is replaced by a broad-leaved forest showed no significant impact on the flood reduction in the URTR. The second simulation was added with 61.75km^2 bamboo forest replaced by broad-leaved forest,the reduction of flood peak discharge and flood volume could be improved significantly. Specifically,flood peak discharge of 10-year return period event was reduced to 7-year event,and the reduction rate of small flood was 21%-28%. Moreover,the flood volume was reduced by 9%-14% and 18%-35% for moderate floods and small floods,respectively. The resultssuggest that the bamboo forest reconstruction is an effective control solution for small to moderate flood in the URTR,the effect of forest conversion on flood volume is increasingly reduced as the rainfall amount increases to more extreme magnitude. Using a hydrological model with scenarios analysis is an effective simulation approach in investigating the relationship between forest type change and flood control. This method would provide reliable support for flood control and disaster mitigation in mountainous cities.

Urban flood control strategy based on new relationship of human and flood

China is one of the countries with the most serious flooding disasters.In China,above 70% of big cities,50% of population and 75% of industrial and agricultural output value are distributed in eastern coastal areas with serious flooding.Therefore,enhancement of theoretical study and experience summarization of urban flood control is of great theoretical and practical significance.As economy is developing rapidly,urban scale is expanding fast,and urban flood control stand is promoted.Urban flood control calls for new concept and methods.This paper makes a systematic summarization of concept evolution and advanced methods concerning urban flood control at home and abroad.The concept of urban flood control has transformed from simple flood control and drainage to coexistence with and use of flood.Flood control measures have transferred form emphasis upon engineering ones to priority to both engineering and non-engineering ones,with special attention to ecological flood control,such as making full use of ecological revetment,ecological realignment of a river,multi-objective management of urban flood detention region,turning flood into resources and utilization of wetlands.

New Challenges and Opportunities for Flood Control in the Huai River: Addressing a Changing River-Lake Relationship

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.

Decision Support System for Flood Control with Applications to Jiangxi Province

Affected by the climatic fluctuation and human activities, significant changes of the flood control situation are taking place in China. In the new century, the flood control systems have to face a series of challenges. In this paper, we design fa decision support system (DSS) for flood control based on its requirements. The DSS has been applied to decision-making for flood control in Jiangxi province, and play an important role in the flood control in the recent two years. Finally, we plot the further improvement on the DSS so that it will make more contribution in the flood control.

FLOOD CONTROL PROGRAMME IN BANGLADESH

Bangladesh locates in lower reach of Ganges-Brahmaputra-Meghma, Bengal delta. Bangladesh is a land of rivers and heavy monsoon rains. Every year during monsoon period (May-September)the country floods of verying magnitude, it causes damages to crops, properties, infrastructures, etc. and ultimately affects the economy development of the country. Banglandesh flood has some features given below: 1. The excessive rainfall over the vast catchment area of the river is the main cause of flood in Bangladesh, but 90% of the flood carried by rivers come from outside the country, i.e. regional countries, India, Nepal,

The flood control and regulation of Three Gorges Project

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.

Improvement Strategies of Flood Control Landscape in Suburban Villages and Towns from the Perspective of Aquaphilia and Livability

In the context of urban and rural integrated development, many suburban villages and towns are still threatened by both urbanization and natural disasters. In order to explore the improvement strategies of flood control landscape integrating water ecology, water safety, water culture and water landscape, the Luozhou Ancient Town by the Wulong River in Fuzhou City was taken as an example, and the concept of pluralistic symbiosis from the perspective of aquaphilia and livability was proposed through field investigation, data monitoring, site analysis and planning, that is, while retaining the positive attributes of “boundary”, its negative limitation of “pluralistic” space is broken, so as to establish a pluralistic and symbiotic environment with aquaphilia and livability. It can not only effectively alleviate the contradictions between urban and rural areas, between water and land, and between old and new cultures, but also activate the vitality of suburban villages and towns, providing a new idea for the improvement of flood control landscape.

THE WARNING OF THE '98 YANGTZE DELUGE & OUR FLOOD CONTROL STRATEGY

Based on a panoramic analysis of the serious Yangtze deluge in 1998 and its hydrological traits, the authors elucidate the formative factors of the deluge and review existing flood-control policies in retrospect. In addition, some countermeas-ures are suggested for coping with similar calamities in the near future.

REMOTE-SENSING TECHNOLOGY IN FLOOD CONTROL IN CHINA

This article expounds the vital role undertaken by telemetry in monitoring and assessment in flood control in China. By analyzing the data from their surveys, the authors give an all-round exposition of problems in the country’s drive for disaster reduction and propose countermeasures in the fight against the possible flood problems in the future.

An Improved Contract Net Protocol with Multi-Agent for Reservoir Flood Control Dispatch

Contract Net Protocol (CNP) has been widely used in solving the problems of multi-Agent cooperates and reservoir flood control optimization dispatch. This paper designs an Agent functional module based on the multi-Agent coordinated the construction of reservoir flood control optimization dispatch and the corresponding Agent to solve the problem of classical CNP in the Agent communication aspect, to enhance the efficiency of reservoir optimization dispatch and to improve the insufficiency of the classical CNP in the application of reservoir flood control dispatcher. Then, the capacity factor and the cooperation level are introduced in the module. Experiments are conducted on the Agentbuilder simulation platform to simulate reservoir flood control optimization dispatching with the improved CNP. The simulation results show the communication interactive efficiency and the performance of new protocol is superior to those of the classical CNP.

Preliminary Study in Spatial Data Warehouse of Flood Control and Disaster Mitigation in Yangtze River Basin

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.

A STUDY OF THE RELATION BETWEEN RIVER REGULATION AND FLOOD CONTROL

Flood control is closely related to the rising level of the upstream. Thechange of the main current and the inshore current velocity is induced by thecompletion of the regulation work. Yet Flood Control Departments pay muchmore attention to the extent,the range and the law of the inshore current velocity increase,especially in the river reaches which have arduous tasks of floodcontrol. Flood Control Departments object to constructing regulation work sucnas groynes,because they have always thought regulation work may lead to theincrease in the inshore current velocity.This paper intends to expound on theinfluences of regulation work on the extent,range and law of the inshore current velocity through analyzing the data obtained from the scale model tests ofthe Jiepai Reach in the middle of the Yangtze River and also discuss the possi-bility of limiting increase of the inshore current velocity through properly ad-justing regulaton work,thus we can correct evaluation of the influence of theriver regulation

基于MIKE FLOOD模型的平原水网地区内涝治理效果模拟研究

为科学评估平原水网地区内涝治理效果,以昆山市淀山湖镇为研究对象,基于MIKE FLOOD模型,耦合一维河网、二维地形和一维管网模拟了平原水网地区城镇内涝情况。采用实测降雨数据对模型进行了率定和验证,并模拟了2年一遇、5年一遇、10年一遇和20年一遇4种重现期降雨条件下现状和治理后的最大淹没水深。模拟结果表明:20年一遇降雨条件下内涝范围变化明显,其余3种重现期降雨条件下内涝范围变化不明显;对于降雨重现期较小条件下的城市内涝治理,应优先考虑管网改造,而针对短历时的强暴雨事件,应优先考虑海绵城市设施建设改造;为了应对不同重现期、短历时降雨造成的城市内涝风险,应在管网改造的基础上配合海绵城市设施建设改造。

Basin flood control system risk evaluation based on variable sets

Flood control system risk evaluation is an effective measure for flood risk management and decisions.In order to make better flood risk decisions and thereby improve social and economic benefits,the flood control risk evaluation index system should be built to quantify and normalize flood risk effectively and efficiently.Because the current evaluation index has the binary miscibility characteristic of fuzziness and clarity,this paper establishes a new flood control system risk evaluation method based on the theory of variable sets(VS).Through a comparison of flood control risk evaluation with variable fuzzy sets(VFS) in the same basin flood control system risk evaluation,it is revealed that the new method,i.e.,flood control risk evaluation with variable fuzzy/clear mixture sets(variable sets),will be reasonable in all cases.Finally,in one case study,i.e.,the flood control system risk evaluation of Fengman Reservoir Basin,which is located in the southeast central of Jilin Province in China,the risk evaluation levels for each county in the basin as well as the whole flood risk distribution map of the basin could be provided with the new method.This provides useful information for basin flood control planning and design.

ON THE HYDRAULIC FAILURE PROBABILITY OF FLOOD CONTROL DAMS

In flood control dams it is not only the failure to prevent flood larger than their design carrying capacity, but also the uncertainties of hydraulic factors that cause disasters. In general, the hydraulic risk is not considered in most of the hydrological analysis in floodproofing plan and design. In this paper, a method of evaluating the hydraulic risk is developed by employing risk theory, and the concept can easily be extended to other types of risk analysis. As a result, it is possible not to consider the hydraulic resks when the design hydrologic risk of flood control dam is lger. Otherwise, the hydraulic risks must be noticed. The research is very helpful for the development of the flood control theory used at present.

FUZZY OPTIMAL DECISIONS FOR MULTIOBJECTIVE FLOOD CONTROL SYSTEM OF CASCADE RESERVOIRS

Based on the practice of reservoir operation, a decision making model of multi objective flood control of cascade reservoir system is presented, which is realistic and effective, combining traditional optimal techniques with fuzzy set theory. In the present paper, the operation alternative is chosen as the decision variable, the outflow process as the state variable, and optimal operation decisions are determined by the fuzzy optimal technique. Finally, the model is delineated by taking a case study of comprehensive flood operation for a cascade reservoir system.