Evaluation Of Water Diversion Project To Northern Zhejiang On Water Environment Of Plain Rivernet In Jiaxing District

Project of inter-basin water diversion is an important measure to balance the spacial and temporal distribution of regional water resource, make sure the rational exploitation and utilization of water resource and achieve optimized allocation of water resource. Project of water diversion to north of Zhejiang province is one of these projects on prospective planning and aims at releasing the scarcity of the water resource in the northern of Zhejiang province and promoting the development of regional economy while some effects on the ecosystem environment of the received region can not be neglected. Therefore, the following works have been done to evaluate the effects of the project to the water environment in Jiaxing by rivernet water environment model:Firstly, based on the complexity of the plain rivernet in Jiaxing District, MIKE11 was selected to model the flows and the transportations of the pollutants in the rivernet and the blocks and functions of MIKE11 were presented.Secondly, the relationship formulation between water price and water demand developed by L.Danglas James and Robert.R Lee has been revised as formula to calculate the amount of the pollutants drained into rivers after taking water-saving and emission reduction into consideration.Thirdly, the rivernet system and the pollution sources in Jiaxing were investigated and simplified for modeling. The water environment model of rivernet in Jiaxing was constructed by MIKE11 and the parameters in the model were calibrated based on the comparisons between the modelling results and the measured data.Finally, the effects of the project of water diversion to the water environment in Jiaxing were evaluated by the established rivernet water environment model,Then the same evaluation was done again in order to asses the mutual effects of the project and the measurements of water-saving and emission reduction. The comparisons between the results of those two cases show that the project of water diversion can dilute the concentrations of some pollutants in some particular river sections to a little extend without changing the categories of water quality. However, once the measurements of water-saving and emission reduction were taken into consideration, the water quality in majority of rivers were improved significantly and some categories were upgraded by one level, which shows that those measurements are more efficient for improving the water environment because of their greatly reduced amount of the pollutants into the rivernet.