The Simulation Study On Water Quality Of Tuo River Exit Section Of Chengdu "Jintang County Wufeng"

Tuo River is the first stage tributary of the Yangtze River.Its mainstream length is about629km,total drainage area is about32,900km2.In recent years industrial pollution sources,domestic pollution and agricultural non-point source pollution is worsening in the river basin area, river water quality is keeping declining,aquatic ecosystems have been seriously damaged,the water environmental capacity of these pollutants in some part of the river has been saturated.In such grim circumstances,controlling the Tuo River basin water pollutants and developing river pollutant reduction program is quite pressing.The water quality model is a kind of mathematical model which uses mathematical theory to describe the migration and transformation of pollutants in aquatic environments and their impact on the relationship between the factors.WASP is a professional water quality analysis simulation program which recommended by U.S. EPA.It is a widely used surface water quality simulation model and also a dynamic multi-box model designed for the analysis of a series of reservoirs, lakes, rivers and coastal water quality problems.In this paper,the WASP water quality simulation software was used to simulate the water quality of the Tuo River JinTang segment.The water quality compliance conditions of Tuo River exit section of Chengdu"Jintang County Wufeng"was proposed.Firstly,the information of river hydrology,water quality,the source,distribution and discharge methods of a major pollution was collected.Then the characteristics of the model of the WASP software was fully familiar with, the application of the model was verified,water body was segmented.And based on investigation of the characteristics of pollution in each river,water quality simulation software was used to forecast segmented river water quality trends,and the impact factors of water quality change was analyzed. Finally, with the simulation results,WASP software was applied in simulating water environmental capacity of nitrogen and phosphorous under different rate of flow assurance in the river.And then based on the calculated results,measures was put forward to remediate key polluting river,river basin area sewage reduction program was developed to ensure the Tuo River exit section of Chengdu "Jintang County Wufeng" reach the water quality standards stably.From the simulation results,the total phosphorus concentration in Tuo River Jintang segment slightly exceeded the standards in the dry,the quantity of the pollutants did not exceed water environmental capacity of the river,so total phosphorus has little effects on the water and has a short impact time.the quantity of ammonia was beyond the capacity of the water environment, and it brought certain negative effects.Therefore, in accordance with the total pollutant control standards,river pollution prevention must be strictly targeted on the river.