Recent Advances of Urban Water Management in China ---- Urban Stormwater Management and Local Pluvial Flood Prevention 2014/12/04 Beijing Integrated Urban

Recent Advances of Urban Water Management in China ---- Urban Stormwater Management and Local

Pluvial Flood Prevention

2014/12/04 Beijing

Integrated Urban Water Management

China Academy of Urban Planning & DesignDHI and Grundfos, Denmark

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

Outline

1. Background

• 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 more and more serious, especially in big cities

1. Background 1.1 flooding events

Beijing, 2007

Beijing, 2008


Beijing 2011-06-23



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.

2013.10 Ningbo 2013.10 Ningbo

2013.10 Shanghai 2013.10 Hangzhou


28 May 2013 Xi’an 16 May 2013 Xiamen

24 May 2013 Fangchenggang 27 May 2013 Shenzhen


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.

1985 2007

Land use in Beijing in 1985 and 2007

Urbanization rate in China since 1990

Urbanization rateGrowth rate

1. Background 1.2 Rapid urbanization

Water bodies are buried, reclaimed to farmland or blocked during the process of urbanization.


The area losses of water body in Wuhan reaches 39% from 1991 to 2000

– 上世纪 50年代城区湖泊 127个，目前仅存 38个，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

Changes of water body in Wuhan （ 1991-2010 ）

Water body losses

Water body in 2010汤逊湖黄家湖

南湖东湖沙湖水果湖

沉湖

武湖


Insufficient input for the drainage infrastructure.

Low design standard for the drainage system.

Insufficient investment for O&M.

≤1 年 1-2 年 ≥3 年0

50

100

150

200 187

20 33

164

35 42

Design return period for pipe line

老城地区新城地区

≤3 年 3-5 年 ≥5 年0

50100150200250 215

11 16

180

35 22

Design return period for pipe linefor important area

老城地区新城地区

Design standard for urban storm water system

1. Background 1.3 Insufficient input and low design standard

Released time Return period of urban drainage system

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.

1. Background 1.4 High attention paid by gov.

2. Recent advances of storm water management

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


2.1 Some important official documents issued


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.


2.2 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.


2.3 Standard, code and technical guidelines are under revised or newly released. Design standard improved



序号标准名称 name Revised/new

1. 室外排水设计规范GB50014-2006 （ 2011 年版）

National code for drainage design revised

2. 城市居住区规划设计规范GB50180-93 （ 2002 年版）

National code for residential area planning and design

revised

3. 城市排水防涝设施普查数据采集技术标准

Technical standard for drainage facilities survey and data collection

new

4. 城市内涝防治规划规范 National code for urban pluvial flood mitigation planning

new

5. 城镇暴雨与内涝防治技术标准

Technical standard for urban storm water management and pluvial flood mitigation

new

6. 城市排水工程规划规范GB50317-2000

National code for urban drainage engineering 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

• 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




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

The 2014 version of design return period of storm drainage pipes

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



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.


2.5 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.



Deep tunnel planning in Guangzhou

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.


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.



2.6 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)


2.6 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.

Shijiazhuang project

Modeling process



31

1

2

3

4

5

1 2 3

4

55


Risk mapping in Shijiazhuang Project


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

Storm water wetland

Detention pond

Grassed detention basin

opening curb

Grassed swale

underground rain water storage tankpervious conveyance

cutting curb

Grassed swale


LID practices in China

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.


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 one-goal-oriented planning may be one possible solution.

3.1 Rationale for integrated urban water management from urban planning perspective


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

Urban water safety plan

Urban water spatial plan

Integrated urban water 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 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.

Urban water supply plan

Urban water environment pollution control 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 should include the water landscape plan, waterfront area conservation and develop plan.

Urban water safety plan

Urban water spatial plan


4. Progress and Plans


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


4.2 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)


4.2 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

Documents

Recent Advances of Urban Water Management in China ---- Urban Stormwater Management and Local Pluvial Flood Prevention 2014/12/04 Beijing Integrated Urban