1. Wu Shiqiang Nanjing Hydraulic Research Institute, China 2015.5.12 Copenhagen Urban Water System Improvement & Sustainability in China

3. Ignoring ecological and hydrological features Irrational linking of river systems Aimless sewage interception and discharge

4. End-of-pipe control Source reducing Interception Since 1980s Restoration Comprehensive improvement : River connectivity Ecological restoration LID city Guilin city Two rivers and four lakes Before (1998) Class III After (2000) Class II Wuhan city Connection of six lakes Before (2008) 4.0% of Class II After (2010) 48.0% of Class II Shanghai city LID city planning

5. ★ City area: 8488 km 2 Population: 13 million GDP: 13000 billion yuan City area: 8488 km 2 Population: 13 million GDP: 13000 billion yuan Situated at the lower reaches of Taihu Basin Time-honored city and The Oriental Venice High-tech industrial base

6. Nan yuan Area Bei yuan area Tao wu area North area Gan jiang river area South area Downtown

7. 3 yrs of improvement action since 2012 Objectives  100% interception of sewage into river  100% channel dredging  100% elimination of dead end rivers  100% coverage of river channel cleaning Procedures Sewage interception---premise Dredging---base Gravity flow---soul management ---guarantee

8. Plan indexes: Q>40m 3 /s, WLD>0.2m, WQ> Cass IV Proper diversion: from Yangtze River and Taihu Lake Field observation 1D model 2D 、 3D model Physical model

9. Combined use of major rivers and lakes Flood Control Engineering System for Taihu Lake Urban Flood Control Engineering System

10. Three-point sources of water supply Improving the downtown water content and guarantee rate Alleviating the water resources shortage Wangyu River on the East Coast Yangcheng Lake Downtown

11. Reasonable water supply  Three weirs were built to raise water level of the north city  Water heads in south and north of the city were maintained

12. Gravity Flow  Operation of water gates to make water supply based on requirement  Water flows from north to south of the city continuously and orderly

13.  Water velocity increased from 0.05m/s to 0.2m/s  Water exchanged once a day  Main water quality indexes improved from lower than class V to III  Increased fluidity of river systems in the downtown  Connection of inner, middle and outer river circles

14. Gravity Flow Project: Explore a new way for plain river network conservancy project Combine engineering and non-engineering measures Embody the idea of harmony between human and water Revelations: Systematic planning and comprehensive management Legal protection and focus on protection Collaborative management and scientific evaluation Public participation and collective benefit

15. sqwu@nhri.cn Thanks for your attention! www.nhri.cn