Jiaxing tap water was built in the 1950s, with groundwater as its source. There was great development in the 1970s and 1980s, and the water source gradually changed to surface water. With the expansion of urban scope and the lag of environmental governance, there has been a major crisis in the source of urban water supply. Facing the restriction of ground subsidence on groundwater exploitation in Zhejiang Province, Jiaxing, located in the south of the Yangtze River, has eight major rivers entering and leaving the urban area, and the large and small rivers are interconnected, making it one of the areas with the highest river network density in the province, but none of them meet the national drinking water source quality standards. Facing the severe water shortage situation, there are only two ways to choose: one is to take water from abroad for a long distance; The other is to turn unqualified raw water into qualified drinking water after advanced treatment. However, it is beyond Jiaxing's power to introduce water sources with qualified water quality and sufficient water quantity. In addition to huge investment and high operating costs, there are also social and ecological problems such as long lines, complicated conditions along the way, cross-administrative regions and cross-basins. Since 1998, Jiaxing Water Supply Company (later renamed Jiayuan Water Supply and Drainage Co., Ltd.) and Shanghai Municipal Engineering Design and Research Institute have conducted long-term field tests on the advanced treatment of slightly polluted water sources in Jiaxing, and these research results have been applied to the reconstruction and expansion project of Shijiuyang Water Plant.