Integrated Urban Water Management Recent Advances of Urban Water Management in China ---- Urban Stormwater Management and Local Pluvial Flood Prevention China Academy of Urban Planning & Design DHI and Grundfos, Denmark 2014/12/04 Beijing Outline 1. Background of urban storm water management in China 2. Recent advances in urban storm water management in China 3. Some preliminary thoughts about integrated of urban water management in China 4. Progress and plan 1. Background 1. Background 1.1 flooding events • River flood have been basically brought under control After the 1998 Yangtze river floods, such a serious flood disaster are rarely appeared. • Urban local pluvial flood are becoming especially in big cities more and more serious, 1. Background 1.1 flooding events Beijing, 2007 Beijing, 2008 1. Background 1.1 flooding events Beijing 2011-06-23 1. Background 1.1 flooding events 2012-07-21 Beijing • Average precipitation was 170mm with the maximum of 460mm in Beijing on 21 July 2012. • 79 people were killed in that event and the total direct damage was estimated to be 10 billion RMB. 1. Background 1.1 flooding events 2013.10 Shanghai 2013.10 Ningbo 2013.10 Hangzhou 2013.10 Ningbo 1. Background 1.1 flooding events 24 May 2013 Fangchenggang 28 May 2013 Xi’an 27 May 2013 Shenzhen 16 May 2013 Xiamen 1. Background 1.2 Rapid urbanization Urbanization rate in China since 1990 Urbanization rate Growth rate China is currently under the process of rapid urbanization. Now more than half of the total population live in the urban. More than 13 million people become living in the urban, resulting in the urban built-up area expand 1300km2 annually. Land use in Beijing in 1985 and 2007 1985 2007 1. Background 1.2 Rapid urbanization Water bodies are buried, reclaimed to farmland or blocked during the process of urbanization. 1. Background 1.2 Rapid urbanization The area losses of water body in Wuhan reaches 39% from 1991 to 2000 武 – 上世纪50年代城区湖泊127个,目前仅存38个, 湖 上世纪80年代湖泊874平方千米,现状645平 方千米 – 38 lakes in Wuhan now compared to 127 lakes in 1950s, 645km2 lakes now compared to 874km2 three decades ago 沉 湖 南湖 东湖 沙湖 水果 湖 Water body in 2010 汤逊湖 Water body losses 黄家湖 Changes of water body in Wuhan(1991-2010) 1. Background 1.3 Insufficient input and low design standard Insufficient input for the drainage infrastructure. 200 Design return period for pipe line 187 164 150 Low design standard for the drainage system. Insufficient investment for O&M. 100 50 35 33 42 1-2年 ≥3年 20 0 ≤1年 老城地区 新城地区 Design standard for urban storm water system Released time Design return period for pipe line for important area Return period of urban drainage system 300 200 215 180 100 35 16 22 3-5年 ≥5年 11 0 ≤3年 老城地区 新城地区 1. Background 1.4 High attention paid by gov. 1.Report on the Central Government Work 2013 : “The investment of the central budget are mainly invested in affordable housing projects, agriculture, water conservancy, urban pipe network and other infrastructure, social programs and other livelihood projects, energy conservation and ecological environment”. And the construction of urban pipe network are involved in the investment from the central government for the first time in history, which may stimulate the development soon. 2.Enhancements of the Construction of urban municipal infrastructure from the State Council of the People's Republic of China stated: To accelerate the construction of urban infrastructure and renovation, market access will be further expanded, and social capital are encouraged to participate in. 2. Recent advances of storm water management 2. Recent advances of storm water management 2.1 Some important official documents issued High attention paid by central government and local government • • • • Notification on the Enhancements of the Construction of Urban Drainage and Urban Flooding-protective Facilities from General Office of the State Council of the People's Republic of China No.〔2013〕23 Advice on the Enhancements of the Construction of urban municipal infrastructure from the State Council of the People's Republic of China Regulation on Urban Drainage and Sewage Treatment from the State Council of the People's Republic of China Advice on the Enhancements of the Construction of Urban underground pipelines from General Office of the State Council of the People's Republic of China No. 〔2014〕27 2. Recent advances of storm water management 2.1 Some important official documents issued Ministry of Housing and Urban-Rural Development of the People's Republic of China(MOHURD) (2013) No. 88 Technical Guideline for census data collection and management of the Comprehensive Urban Storm Water Drainage and Localized Pluvial Flooding Mitigation Facilities. MOHURD (2013) No. 98 Technical Guideline for the Formulation of Comprehensive Urban Storm Water Drainage and Localized Pluvial Flooding Mitigation Planning. MOHURD (2014) No. 66 Revising of storm intensity formula. MOHURD (2014) No. 275 Technical Guideline for the construction of “Sponge City”——Construction of storm water system with the concept of low impact development. 2. Recent advances of storm water management 2.2 A lot of research projects are and will be supported Money from Asian Development Bank, Ministry of Science and Technology, State Key Research Project for Water and National Natural Science Foundation committee. 2. Recent advances of storm water management 2.3 Standard, code and technical guidelines are under revised or newly released. Design standard improved 2. Recent advances of storm water management 2.3 Standard, code and technical guidelines are under revised or newly released. Design standard improved 序号 标准名称 name Revised/new National code for drainage design 室外排水设计规范 GB50014-2006(2011年版) 城市居住区规划设计规范 National code for residential area planning and GB50180-93(2002年版) design 城市排水防涝设施普查数 Technical standard for drainage facilities survey and data collection 据采集技术标准 National code for urban pluvial flood mitigation 城市内涝防治规划规范 planning 城镇暴雨与内涝防治技术 Technical standard for urban storm water management and pluvial flood mitigation 标准 National code for urban drainage engineering 城市排水工程规划规范 GB50317-2000 planning revised 7. 城市用地竖向规划规范 CJJ83-99 National code for urban vertical planning revised 8. 城市绿地设计规范 GB50420-2007 National code for green space design revised 1. 2. 3. 4. 5. 6. revised new new new revised 2. Recent advances of storm water management 2.3 Standard, code and technical guidelines are under revised or newly released. Design standard improved • The national standard and guideline of storm water runoff control are being studied. Local standards : Code for Design of Storm water Management and Rainwater Harvesting Engineering in Beijing 2013 Method for implementing management guideline of Comprehensive low impact development and storm water utilization planning Guide for Low Impact Development storm water system technology 2. Recent advances of storm water management 2.3 Standard, code and technical guidelines are under revised or newly released. Design standard improved Released time The return period of urban drainage system 1975年 0.33-2 1987年 0.5-3 1997年 0.5-3,重要地区(important areas)2-5年 2006年 0.5-3,重要地区(important areas)3-5 2011年 1-3年,重要地区(important areas)3-5 The 2014 version of design return period of storm drainage pipes Central area Suburban area Important central area Underground, underpass, low-lying square Megacities 3~5 2~3 5~10 30~50 Big cities 2~5 2~3 5~10 20~30 Small and medium cities 2~3 2~3 3~5 10~20 2. Recent advances of storm water management 2.4 Dual drainage system concept widely accepted minor system:Minor system is designed to collect and discharge the common urban rainfall water (design storm return period is usually 2 to 10 years), which is also called conventional drainage system. major system:Major system is designed to discharge runoff water generated by heavy rain water (usually 50-100 year return),and dominated by drainage channel. Through the drainage channel and deep drainage tunnel, the runoff water exceeding the capacity of minor system is discharged out of the city. 2. Recent advances of storm water management 2.5 New version of planning are under formulated and some practices already on the way • The new version of storm water drainage and local pluvial flood mitigation plan is currently under formulated in more than 600 cities and and more than 1000 counties according to the technical guidelines issued by the MOHURD, which was finished mainly by CAUPD. • About 14 planning projects of this type are currently carried out by CAUPD and DHI China participated in it extensively. • All these planning are supposed to be finished in this year and then submitted to MOHURD. CAUPD was commissioned to review and assess all the planning files mainly from the technic perspectives. 2. Recent advances of storm water management 2.5 New version of planning are under formulated and some practices already on the way Some cities including Shanghai, Guangzhou and Wuhan now consider deep tunnel as a possible solution to address the Combined System Overflows (CSOs) and local pluvial flood simultaneously. Guangzhou is already on the way of construction and others are under feasibility study. Deep tunnel planning in Guangzhou 2. Recent advances of storm water management 2.5 New version of planning are under formulated and some practices already on the way Many construction practices are carried out in Beijing, Shanghai, Shenzhen, Changde and many other cities. The approved comprehensive plan is implemented and many drainage facilities including some large scale retention/detention tank are built. 2. Recent advances of storm water management 2.6 Hydraulic modeling and risk mapping are now extensively accepted and used Rational method was widely used in China in the past for the storm water system calculation while EU and US recommend the hydraulic modeling especially for the large catchment (In EU, the threshold is 200ha according to EN-752) 2. Recent advances of storm water management 2.6 Hydraulic modeling and risk mapping are now extensively accepted and used In the Technical Guideline for the Formulation of Comprehensive Urban Storm Water Drainage and Localized Pluvial Flooding Mitigation Planning, which was drafted by CAUPD, Hydraulic modeling was required for drainage network assessment, flood risk mapping as well as planning evaluation for catchment larger than 200ha, despite some strong opposition from many experts. The Guideline promote the booming of hydraulic modeling and pluvial flood risk mapping. Some official software including DHI and HR Wallingford benefit a lot from it from both the marketing and technic perspective. 2. Recent advances of storm water management Shijiazhuang project Modeling process 2. Recent advances of storm water management 2. Recent advances of storm water management Risk mapping in Shijiazhuang Project 1 2 4 4 5 3 1 2 5 3 31 2. Recent advances of storm water management 2.7 Source control and LID concept widely accepted, much attention paid to non-structural measures Central park in Chongqing Beichuan County in Sichuan Province 2. Recent advances of storm water management LID practices in China cutting curb opening curb Detention pond Storm water wetland Grassed swale Grassed swale Grassed detention basin pervious conveyance underground rain water storage tank 3. Some preliminary thoughts about integrated urban water management in China 3. Some preliminary thoughts about integrated urban water management in China 3.1 Rationale for integrated urban water management from urban planning perspective Lot of urban planning exits in China. For urban water supply sector, we have urban water resources plan, water supply engineering plan, reclaimed water plan or even some desalination plan and rainwater harvesting plan. These planning are mean to address the urban water supply in different perspectives but they are not one-goal-oriented, and poor coordination between different planning can be found. This issue need to be handled to make sure that all these plan may address the water supply coordinately. 3. Some preliminary thoughts about integrated urban water management in China 3.1 Rationale for integrated urban water management from urban planning perspective Another case is the urban water environment, which is related to wastewater collection and treatment, first flush of rainwater, combined system overflows, network misconnection, sewer leakage and so on. But currently the wastewater drainage plan could not address the water environment pollution perfectly. Obviously it’s not realistic or even possible to change the urban water management framework, which is related directly to the different government sector’s power and interest. But to integrate the various water related planning to formulate onegoal-oriented planning may be one possible solution. 3. Some preliminary thoughts about integrated urban water management in China 3.2 Advices for integrated urban water management from urban planning perspective The current various urban water related plan can be integrated into urban water supply plan, urban water environment pollution control plan, urban water safety plan and urban water spatial plan. Urban water supply plan Urban water environment plan Integrated urban water plan Urban water safety plan Urban water spatial plan 3. Some preliminary thoughts about integrated urban water management in China 3.2 Advices for integrated urban water management from urban planning perspective Urban water supply plan Urban water supply plan should include urban water resources, water treatment, water distribution, reclaimed water supply and rainwater harvesting. Urban water environment pollution control plan Urban water environment pollution control plan should include the wastewater collection and treatment, sludge disposal, first flush pollution control, combined system overflow, misconnection of storm water system and sewer system, sewer leakage and et cl. 3. Some preliminary thoughts about integrated urban water management in China 3.2 Advices for integrated urban water management from urban planning perspective Urban water safety plan Urban water safety plan should include urban fluvial flooding, tidal flooding, storm surge, urban local pluvial flooding, storm water drainage, underground water ponding and wastewater flooding. Urban water spatial plan Urban water spatial plan should include the water landscape plan, waterfront area conservation and develop plan. 4. Progress and Plans 4. Progress and plan 4.1 Progress • Inception workshop of China Europe Water Platform Co-lead 5th March 2014 in Beijing • Seminar in World Water Week 4th September 2014 in Stockholm • Inception workshop 13 October in Shanghai • NRW Theme day 14 October in Shanghai • Agreement on Urban flooding activities with Flood management Co-lead • Meeting between partners on future activities • Meeting between partners 2rd December 2014 • Seminar on pricing for water 3rd December 2014 • Participation in annual meeting 4th December • Draft work plan for 2015 4. Progress and plan 4.2 Plan • • • • • • Urban water resources (water supply, water reuse, storm water harvesting, blue and green cities) Urban storm water management and flooding, sustainable urban drainage system (low impact development) Water in the urban landscape – living with the water and recreational use of water Urban water environment, protection and pollution control Non-revenue water and pressure management in urban water supply (saving water resources and energy for water supply) Construction of Sponge City(LID measures Planning, promotion of construction concept and technology) 4. Progress and plan 4.2 Plan • Participate in side event during World Water Forum, Korea 2015 • Organise seminar during Annual meeting in Copenhagen, May 2015. Topic could be related to policy and management of urban water • Inventory of European urban experiences to share: Examples from all over Europe: Hamburg, Berlin, Rotterdam, Paris, Amsterdam, Copenhagen, Stockholm etc. Starting point for joint projects and identification of partners in China. Examples are key topics for IUWM (NRW, Storm water, water in landscape, eco-cities, integrated solutions) • World Water Week in Stockholm, August, 2015 • Seminar in China, September 2015 • Seminar in November 2015 on urban flooding at International Water Week in Amsterdam. Thanks