On City Taicang's water transfer environment and acorresponding simulated model for its improvement

This paper aims at analyzing the effect of water transfer on the quality of water and establishing a mathematical simulation model to improve the City Taicang's water environment.The water experiment presented here was done on April 21,2004.The whole monitoring project consisted of the water level,water quantity and water quality(COD_(Mn),NH~+_4-N) involved in the city.For the research purposes,the authors divided the whole water levels into 16 sections,and the water quality monitoring system into 19 sections.It took a period of time of 14 hours and water was transferred to the city up to 218 000 m~3.The data of water volume and water quality were obtained under the sampling of the test point.From the result of the water transferring experiment,it was found that the city's water environment has been improved to some extent,and the average improvement of COD_(Mn) was 2.7 mg/L.Especially in section 4,the improvement was up to 6.5 mg/L.Based on the data of experiment,we have established the city's hydraulic and water quality simulated models and analyzed the degree of its water environment improvement.At the same time,the improved degree of the city's water environment was shown under the different water diversion projects and the results of clearing-away of sludge and getting rid of pollutant sources.From the achievement rated,it can be found that the calculating values of water quantity and water quality by mathematic model in every section are well into conformity with the monitored value with the relative errors being about 10%-20%,which indicated that the simulated model is practical and feasible for its purpose.Through the research,it can be concluded that the transferring water can improve the urban water environment only temporarily,while radical improvement of the water environment of the city is cutting down the pollutant sources.