Pollutant Discharge Permit Allocation Method Based On Water Quality Standards At The Small Watershed

The investigation of the environmental capacity of water and the implementation of control of the total amount of pollution is the most important part of the basic technical work of management of the aquatic environment and are also important management measures to guarantee the quality of the aquatic environment and promote the sustainable economic and social development in the basin area.With the development of the social economy in our country,the problem of water pollution is becoming increasingly serious and it is urgent to carry out scientifically effective water pollution control work.Therefore,it has a great theoretical value and a practical importance to study the capacity of the water environment and the total amount of pollutants in a river basin.In this paper,based on the analysis of the practical needs of control of the total amount of water pollutants in the Shuangqiao River basin,small basin of the Anhui Shuangqiao River as an example,assimilation capacity and distribution scheme investigation pollution load of the Shuangqiao River basin,the main investigation includes the region upstream and downstream of the Shuangqiao River of the west flood diversion zone of the Shuangqiao River area.Through data collection and data compilation,the current status of pollution sources in the Shuangqiao river basin was analyzed and calculated.The state of the aquatic environment in the basin was further investigated and analyzed to determine the main sources of contamination.On this basis,COD,NH₃-N and TP were selected as the main sources.Pollution factor,using the one-dimensional water quality model to measure the environmental capacity of the Shuangqiao river basin.Based on the results of the calculation of the capacity of the aquatic environment and the current status of the discharge of pollutants,the capacity of the remaining water environment in the Shuangqiao river basin was obtained.Results show that to ensure water standard of the Shuangqiao River environment capacity of COD,NH₃-N and TP was-755.7 t/a,38.42 t/a,and-3.438 t/a.According to the TMDL principle,based on the contribution rate of each pollution load,combined with the current pollution situation in the Shuangqiao River basin,the total load distribution of the TMDL contamination sources is carried out,and the Point pollution and non-point reduction plans are formulated.The results showed that the point to sources and surface source charge ratios of NH3-N were 50.53%and 48.66%,respectively;urban life from point sources decreased by 17.59t/a;rural life of superficial origin,decentralized livestock and poultry breeding,and concentrated breeding of livestock and poultry.Agricultural sources,urban surface runoff,landfill leachate and aquaculture,respectively,reduced 16.6 t/a?0.45 t/a?0.47 t/a?1.63 t/a?0.04 t/a?0.13 t/a?0.41 t/a.In this study you have a brief analysis of the key problems in the total water pollutant control capacity in the Shuangqiao River basin and the key issues in the distribution of the pollutant load,explore the method of the total allocation of water pollutants,formulate a pollution load reduction plan,and form a small basin system.The total amount of pollution load distribution technology.The water environment management system in the Shuangqiao River basin was upgraded to provide technical and baseline support for simulating the water quality of similar small basins with scarce baseline data.At the same time,the small basin of the Shuangqiao River fully implements water quality objective management technology and lays the foundation for improving water quality in the Chaohu Lake basin.