In recent years, Huai'an City has adhered to the "Four Sources Co-Governance" approach, making every effort to improve the water ecological environment of Hongze Lake.

The first is to enhance the management and control of domestic pollution sources. Annual plans have been developed for the construction and renovation of sewage treatment facilities and pipelines. The three counties and districts around the lake—Hongze District, Huaiyin District, and Xuyi County—have collectively completed the construction of 26 sewage treatment quality improvement areas, covering 74.54 square kilometers, with an additional daily sewage treatment capacity of 70,000 tons. The management and control rate for rural domestic sewage within a 1-kilometer range on both sides of Hongze Lake and its major inflowing rivers has reached 100%.

The second is to strengthen the control of agricultural pollution sources. A comprehensive approach has been taken to address three major issues: agricultural drainage, aquaculture tailwater, and livestock manure. Ecological farming experimental units have been organized, with a cumulative area of 26,000 mu for agricultural drainage utilization, 26,100 mu for aquaculture tailwater recycling, and 3,800 mu for livestock manure resource utilization completed by 2024.

The third is to enhance the management of industrial pollution sources.  Efforts are being accelerated to promote energy-saving and carbon-reduction technological upgrades for key energy-consuming enterprises along the lake. Clean production audits have been implemented for 12 enterprises. Industrial wastewater is being collected and treated in a classified manner, with three projects—the upgrading of the Qingjian Sewage Treatment Plant in Hongze District, the construction of the Honggang Sewage Treatment Plant, and the expansion of the second sewage treatment plant in Xuyi County—successfully completed and put into operation.

The fourth is to strengthen the management of ship pollution sources. A comprehensive initiative has been launched to address the "Two Ships" issue on Hongze Lake, aiming to eliminate houseboats and dining boats in the lake area. An innovative integrated supervision model for waterborne traffic has been implemented, fully advancing the integrated management of ship water pollutants, ports, and cities, with the closed-loop rate for the transfer and disposal of various pollutants maintaining above 95%, in line with provincial targets.