Study On Pollution Calculation And Water Environment Capacity Simulation For Weihe River In Shaanxi

Weihe River is the biggest river and principal surface water source in Guanzhong Basin. Nowadays, with the fast urbanization of this area, population has increased quickly, and in addition to agriculture, industrial and commercial activities have greatly influenced the water environment of Weihe River. Last year, several parameters were monitored for Weihe River and its some branches such as pH, conductance, water temperature, turbidity, CODMn, BOD5, NH3-N, TN, TP and heavy metal. The data indicate that the water quality in Weihe River is poor than that of the national standard grade V for surface water and Organics are the main pollutants. With the help of GIS, the geo-database is established, the distribution of pollution load is described and the value of pollution load in every region is calculated . The results show that the domestic and the industrial wastewater are the key pollution source in Guanzhong Basin, and the CODCr pollution load arrives 5.34 X 108kg/year, of which 1.58 108kg/year comes from industries.With the help of EPA-WASP6 (Water Quality Analysis Simulation Program), the water quality of Weihe River in 2000 is modeled, which explains the rules of CODCr transform in River effectively. At the same time, the WEC (Water Environment Capacity) is simulated by WASP6 for Weihe River. The value of WEC is about 141830.3kg/day, the amount of pollutants flowing into river should be cut 77.2% at 90% probability of flow.Anyway, powerful measures should be taken to improve water quality for Weihe River. Above all, the flow in river must be enough to dilute the inflowing pollutants. But, it is most important to close paper mills and decrease the pollution load into the river.