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.

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.

Methodological Proposition of an Integrated System for Urban Floods Control

In the State of Santa Catarina, Brazil, especially in the Itajai valley, there are records of accidents and disasters mainly associated to landslides and floods, which have caused significant damages and losses, including human lives. In order to make the coexistence with such natural disasters possible, most particularly with floods, a integration is required among the technical, political, environmental, and human knowledge. Measures that encompass integrated actions for the entire river basin, with the help from an updated technical cadastre and tools, such as the GIS, allow the development of planning tools that might effectively help the people to live with the water, or else to cope with floods in a more appropriate manner. This paper attempts to propose a methodology for urban flood control, based on the integration among the several public entities involved in the flood control, along with the CTM （Multipurpose Technical Cadastre） and GIS tool. In order to solve or minimize the problems, the model proposed here aims at promoting a balance between the agents involved, and enables to rank the degrees of importance assigned to the different needs, thus allowing to eliminate or to improve those areas and processes that are duplicated or superimposed.

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.

Effect of Flood Peak Discharge Control by a Small Reservoir in an Urbanized Area—Case Study in the Kurabe River Basin, Japan

Recently severe damage of flooding by urbanization was frequently occurred. To prevent this damage, small reservoir was constructed in the urbanized residential area. This paper describes an effect of flood peak discharge control by a small reservoir (control reservoir) caused by rapidly developed urbanization. Although work for this purpose was conducted, research on the effects of the control reservoir was not conducted until now. This research, conducted by simulation, was a case study in the Kurabe River Basin in the Tedori River Alluvial Fan Area, Japan, based on the precise investigation of the reservoir in the actual field. The study was conducted to determine not only the actual control reservoir capacity for the newly developed residential area but also the ideal capacity for all present residential areas and the largest capacity allowable for a maximum rainfall event that recently occurred. The control reservoir effects between individual blocks and the entire basin area were compared by dividing the test basin into 15 blocks (sub-basins). The results showed that the effects on the capacity per unit area of the residential area in blocks have close relationship with the decreasing ratio of peak discharge in blocks. Consequently, the effects of control reservoir capacity and the limitation were clarified. In the future, control reservoirs should be constructed for all of the already developed residential areas, for example, by utilizing underground car parking lot. The results of this research can contribute to the design of the control reservoir for protection against flooding damage in urbanized areas.

Characteristics of Rainstorm and Flood Disaster in Shaoyang City and Flood Protection Countermeasures

Based on ground meteorological observation data at 10 representative stations of Shaoyang City during 1951-2017 and rainfall data at over 220 automatic weather stations during 2005-2017,statistical analysis on rainstorm and flood disaster in Shaoyang was conducted. Occurrence characteristics and rule of rainstorm and flood disaster were found,and disaster situation was evaluated and analyzed. The results showed that（ 1）there was almost local rainstorm and flood in Shaoyang City every year,with strong seasonal characteristic.（ 2） The loss caused by rainstorm and flood disaster was the most serious in various meteorological disasters.（ 3） Rainstorm and flood disaster generally had the sudden and devastating characteristics. Via the analysis and research on rainstorm and flood disaster,defense measure and countermeasure of rainstorm and flood were proposed,which could provide scientific decision basis for party and government leading flood relief,and had important guidance significance for preventing and mitigating disasters by government agencies.

城市洪涝治理与韧性城市建设:变革、创新与启示

我国城市洪涝治理经历了从工程措施到工程与非工程措施并举,从洪涝分治到洪涝统筹,从城市局部治理到流域系统治理的重大转变。特别是海绵城市和韧性城市理念的引入,显著提升了城市洪涝治理水平,促进了城市可持续发展。经过多年探索与实践,我国在技术应用、政策管理、公众与社会参与等方面取得了显著进展,城市洪涝模拟与风险评估取得重要成果,监测感知系统日趋完善,预报预警技术取得突破,应用场景更加广泛;跨部门协作与联动机制、政府与社会资本合作模式的提出,高效信息传播机制和公众参与程度的加强,均显著增强了城市应对洪涝灾害的能力,为防洪减灾工作提供了有力支撑。借助北斗卫星、激光雷达、物联网、人工智能、大数据等先进技术,我国持续推进数字孪生流域、国家水网与区域水网建设,为洪涝治理和水利高质量发展提供了重要支撑。今后,城市洪涝治理将继续朝着系统化、智能化、生态化方向发展,面对新时代的机遇与挑战,应结合海绵城市与韧性城市建设,坚持系统治理、坚守底线思维、坚持创新发展,通过全局性谋划和整体性推动,不断提升水旱灾害防御水平和水安全保障能力。

城市曲面应急防洪屏结构优化研究

研发新型防洪抢险装备,对于防御城市洪涝灾害,保障城市生命线安全具有重要的意义。采用数值仿真模拟的方法,分析了城市曲面应急防洪屏(以下简称“防洪屏”)曲面拱度对结构受力特性的影响,进一步对防洪屏的结构体型进行了优化研究。结果表明:在同一挡水工况下,随着曲面拱度的增大,防洪屏在同一挡水条件下,所承受的应力逐渐减小,变形明显改善;根据计算结果提出了优化方案,优化的新体型防洪屏在水深小于0.8 m,流速小于1.0 m/s挡水工况下,结构最大应力小于材料特性指标安全极限阈值,满足挡水安全稳定要求,可以作为定型装备推广应用。研究成果为城市曲面应急防洪屏的优化设计提供了重要参考依据。

以韧性城市理念提升城市排水防涝能力的实践

随着城市化进程的加快,城市内涝问题日益凸显,对城市可持续发展构成挑战。本文基于韧性城市理念,探讨了城市排水防涝能力提升的思路与实践。首先阐释了“人水共生”理念的内涵、基本理论与实现途径,以及其与韧性城市理论的关联;并基于当前我国城市排水防涝体系建设存在理念缺失、规划滞后、建设不足和管理局限等问题,提出了系统观念、洪涝统筹、蓝绿灰融合和科技赋能等城市排水防涝能力提升思路。同时,通过梳理近年来在石家庄市、成都市、三亚市和信阳市开展的提升城市排水防涝能力规划项目的实践经验,提出了未来城市内涝治理的方向,包括转变传统治理理念、采用绿色措施、多维度综合治理、优先考虑自然解决方案和坚持“中西医结合”的方式,以期对未来持续开展城市排水防涝工作提供借鉴,以实现我国城市洪涝韧性的持续提升。

基于高分子材质的L型城市应急防洪屏受力分析

国内关于高分子材质城市内涝应急防御装备的研究较为少见。采用水槽试验与流固耦合数值仿真相结合的方法,对城市应急防洪屏(以下简称“防洪屏”)的结构受力特性展开研究。结果表明,数值仿真模拟与试验结果吻合较好。随着水深和流速的增大,防洪屏的应力和变形逐渐增大,最大应力位于防洪屏的踵部,最大变形位于挡水面顶部两侧。防洪屏的结构受力系数随着来流弗劳德数的增大快速衰减,当弗劳德数大于0.15后,结构受力系数趋于定值;相对于惯性力,防洪屏承受最大应力的影响因素主要是重力。研究结果可为防洪屏的进一步优化设计提供参考。

天津市防洪圈内涝与大清河流域洪潮遭遇分析

天津市防洪圈地处海河流域下游,紧邻渤海湾,其防洪安全受流域上游洪水、区内涝水及下游潮水共同影响。以天津市城市防洪圈与大清河流域河口段为例,选取洪水代表水文站、平原区涝水雨量代表站、入海口潮位代表站同期相关要素,考虑洪水传播时间,分别按洪水为主、涝水相应,洪水为主、潮位相应,涝水为主、洪水相应,潮位为主、洪水相应等方式,进行洪、涝、潮的遭遇分析,得出遭遇组合的规律,为优化防洪排涝工程布局提供基础支撑。

适应我国不同自然条件类型城市的内涝治理模式研究

【目的】为加强各地内涝治理措施对区域气候特点、地形水系等自然条件的针对性,【方法】将我国城市根据自然条件差异分为北方少雨城市、平原河网城市、山地丘陵城市、滨海临江(河)城市4种类型,并筛选银川、苏州、宜昌、深圳4个城市分别作为案例,结合近年来内涝发生情况、风险评估及治理情况,梳理和剖析案例城市内涝主要原因、采取的治理措施和成效、面临的主要问题等;对照“源头减排、管网排放、蓄排并举、超标应急”的城市排水防涝工程体系,进一步细化延伸,研究提出不同类型城市的内涝治理模式。【结果】由于内涝成因差异,不同类型城市在管网建设、蓝绿空间保护、洪涝统筹、应急调度等方面工作的侧重点应各有差异。北方少雨城市应以补齐管网系统短板和保护修复蓝绿空间为主;平原河网城市应以保护水网格局、优化水系调度、增加强排能力为主;山地丘陵城市重点则是做好应对山洪的工作,强化排涝通道建设;滨海临江(河)城市需统筹洪涝潮关系,探索弹性空间建设,提高防汛应急和灾害响应处置能力。【结论】为应对气候变化条件下愈加频发的极端降雨,各地应结合自身自然条件,补齐内涝治理工作短板,持续提高城市的空间韧性。研究结果对于各地优化内涝治理工作思路具有一定的参考价值,为各地有效应对内涝灾害提供借鉴。

基于MIKE FLOOD模型的西北城市河道橡胶坝群洪水风险分析研究

由于西北城市河道比降大,暴雨和山洪形成河道洪水突发性强,河道橡胶坝群的修建改善了城市生态环境,同时也客观上增大了城市洪水风险。基于MIKE FLOOD水动力学模型,对西北城市橡胶坝群河道典型案例进行了一二维耦合水动力学模型计算,研究了在河道遭遇大洪水时橡胶坝群未塌坝运行的洪水动态演进情况,定量计算了对城市可能造成的淹没情况以及洪灾损失,指明了橡胶坝群未按照防汛预案采取度汛措施而造成的潜在洪水风险,并且提出了降低城市河道橡胶坝群洪水风险的建设管理措施。

城市隧道防淹技术体系研究

为解决近年来频发的极端暴雨天气导致的城市隧道淹水问题,首先,通过相关文献及新闻报道梳理国内外城市隧道发生淹水致灾的原因和已有城市隧道相关的防淹经验;其次,对现有全国主要城市关于隧道防淹的现行政策、标准以及城市隧道运营阶段涉及防淹工作的内容进行研究总结。在此基础上,对城市隧道的防淹措施开展研究,将城市隧道防淹措施分为6大系统:1)挡水系统,提升隧道出地面范围的防洪能力;2)截水系统,提前截流隧道外部水;3)排水系统,确保隧道内部排水系统顺畅并满足高标准暴雨重现期的排水需求;4)控制系统,保证隧道排水系统正常工作的供配电和控制系统;5)预警系统,增加隧道内外淹水预警装置进行提前防范;6)应急系统,提出发生淹水事故后的应急保障措施。综合城市隧道养护等级、隧址范围内城市内涝风险等级,确定城市隧道的防淹分级可分为1级、2级和3级,并根据城市隧道的防淹等级确定已有城市隧道的防淹改造方案或待建隧道的防淹设计要求。

城市轨道交通车辆基地防洪设计及监测方案研究

[目的]城市轨道交通车辆基地防洪关系到车辆基地及正线运营安全,为有效提高车辆基地防洪能力,需对车辆基地防洪设计要点及措施进行研究。[方法]从设计阶段对影响车辆基地防洪的场坪标高、改移河道设计等要点及注意事项进行详细分析;针对可能出现的大量积水通过车辆基地U型槽进入正线区间造成行车事故的不利情况,开展了防洪措施设计研究,分析确定了出入段线U型槽处为车辆基地防洪关键点;为提高其防洪应急处置能力,从水灾演化规律、监测原则、等级判断及预测、方案设计、智能决策及应急调度等方面进行了防洪及监测方案研究。[结果及结论]在出入段线U型槽位置,采用可移动拼接式防淹挡板设计方案;明确了防淹挡板设计及布置方案、专业接口要点、适用情况;通过设置水位监测点并结合监测融合算法系统、智能决策系统及应急调度指挥系统,构建了出入段线水灾监测、智能决策及应急调度方案,实现灾前、灾中、灾后全过程智能防洪预警及调度指挥。

广东茂名市防洪能力提升思路探讨——以“2022.7”小东江流域特大暴雨洪水为例

广东茂名市现状防洪标准较低,受限于城市发展现状,城区堤防达标建设存在难度。提出将小东江和好心湖进行水系连通,构建小东江及根子河河网一维水动力模型,采用2022年7月洪水数据对模型进行率定,研究利用好心湖蓄洪对小东江茂名市城区段水位的影响。结果表明,当小东江上游车角山水位站发生和小东江支流长山园水位站“2022.7”暴雨洪水过程及量级相同的超50年一遇洪峰流量的洪水时,若好心湖初始水位取死水位13.74 m、闸门宽度取10~100 m,则小东江茂名市城区段峰值水位可降低0~0.03 m,闸门最大进口流量为1.6~13 m^(3)/s;若好心湖初始水位分别取11.74 m和9.74 m、闸门宽度取10~50 m,则小东江茂名市区段峰值水位可分别降低0.10~0.39 m和0.24~0.94 m,闸门最大进口流量分别为41.5~152.2 m^(3)/s和103.8~339.2 m^(3)/s。基于此,好心湖和小东江水系连通时的闸门宽度取20~30 m为宜,研究结果可为茂名市防洪能力提升提供参考。

城市地下空间水灾害防治若干科技问题研究展望

在综述国内外城市地下空间水灾害状况和防灾研究现状的基础上,梳理了研究成果及案例分析,将城市地下空间遭受的水灾害性状归纳为两大类型问题:一类为地表洪涝灾害导致的地下空间水淹灾害,另一类为工程活动或周边水环境特征变化导致的水灾害。解析了城市地下空间内、外部水灾害环境关联响应关系。基于城市地下空间水灾害分布的复杂性,从灾害成因的关键要素和耦合响应关系入手,总结了当前国内城市地下空间水灾害防治存在的一些共性科学难题和技术瓶颈,多目标多层面分解地下空间水灾害防治科学问题和关键技术路线,系统性提出了应该重视和加强研究的若干科技问题及解决路径。并从科学问题、关键技术和解决措施三方面展望城市地下空间水灾害防治领域的科技发展。

我国内涝治理政策梳理及探讨

近年来,内涝灾害防治成了全球性的复杂问题,严重影响人民正常生产生活和生命财产安全。我国高度关注城市洪涝问题,十八大以来,为加强城市内涝治理,已经发布了一系列政策文件,为城市内涝治理指明了方向,提供了原则性和普适性的治理思路。为深刻领会相关政策精神,指导各地开展内涝治理工作,从治理目标、治理思路、重点任务、保障措施等几方面,对既有文件进行梳理总结,提出落实政策要求的建议,为各地推进城市内涝治理工作提供参考。

城市电排站稳定排查分析及其备用电源改造实践

东莞市是我国经济发展重要区域,城市内部水利基础设施完善,但建设时间久远,存在许多影响水利设施正常运行的问题。通过对东莞市城市排站进行安全排查鉴定,发现主要存在配备电源比率低,防雷接地系统不完善,机电设备隐患大3个问题,使得城市的防洪排涝能力大大下降。针对安全鉴定结果,对城市排站备用电源进行改造,在排站设置移动电源,解决电源供应不足的问题,保证排站的正常运行。

连云港市洪涝风险评估与调控研究

对连云港市的地理位置、气候特征、防洪措施等进行分析,通过引入先进的风险评估模型和技术措施,有效识别主要的风险源和风险区域。基于各项工程措施及非工程措施,对连云港市城市洪涝风险进行模拟与评估,提出有效的调控措施,以期为城市管理和相关规划提供参考。