Regulation Effect Of Pollution Prevention And Water Diversion Project Based On Both Water Quantity And Quality In The Nansi Lake Basin

Water quality in the Nansi Lake is very crucial to the water safety of the EastRoute of South-to-North Water Diversion Project. Therefore, it is very important toimprove efficiencies of pollution prevention and water diversion (PPWD) projectswhich are constructed in the Nansi Lake basin through effective regulation based onboth water quantity and quality. Following works have been done in this paper:1. For12PPWD projects, design regulation capacity, design reclaimed-waterdischarge load, design amount of irrigation water, and design runoff from upstream areanalyzed. Design regulation abilities of two typical PPWD projects have beenevaluated.2. Balance relationships of both water quality and quantity in each pollutioncontrol unit of PPWD projects have been established. Optimal regulation principle andalgorithm have been proposed. Finally, the regulation model based on both waterquantity and water quality has been developed for the PPWD projects in the Nansi Lakewatershed.3. The developed regulation model was applied to the PPWD project in theDongyu River. The pollution prevention effects between the original design and theoptimization regulation scheme were compared under seven scenarios of runoffupstream runoff and irrigation water demand. The improvement of pollution preventioneffect of the PPWD project through carrying regulation based on both water quality andquantity was analyzed.The results indicated that it can fully maximize the project capacity of pollutionprevention and storing through dynamic regulation according to water quantity andquality variation of upstream inflow and irrigation water demand change. It hassignificant effect on ensuring water quality safety of the Nansi Lake during waterdelivery period. The regulation principles are reasonable and helpful for the PPWDproject regulation, which include:(1) discharge water when the water quality meets tothe Water Quality Criteria at end control section;(2) Irrigation water demand should besatisfied though regulation sluices or dams.