Rainfall Runoff Affecting On The Combined System Stream Water Quality On Rainy Day

Along with the speed of today’s urban China, the process the great development in productivity, while urban water pollution has already attracted wide, the state promulgated a series of environmental policy,90 years from the last one century to the beginning of this century, a large number of sewage treatment facilities in operation, the current sewage treatment plant has spread to the county-level cities, the current water pollution control focused primarily on point source pollution. But the solution to the point source problem and to ensure that the water environment safety, research shows that even if we fully solve the case of point source pollution, reservoirs and other natural water bodies of the compliance less than 50% of the rainfall runoff pollution, a great impact on water pollution, and rainfall distribution in time is random. In this paper, the old city as the study area of Hefei, Hefei old city drainage system is combined system for the interception type, but part of the closure does not completely discharge, rain overflow pollution is serious, there may be water intrusion mouth closure case, the sewage plant influent concentration, partial low; triage system used in other regions, however, received rain sewage mixed with serious, no control measuresin the initial stormwater pollution, the source of urban nonpoint source pollution control are not taken seriously and implemented, similarly led to the pollution of urban water bodies. In this study, by choosing different underlying surface, the representatives of the road and lawn areas, screening of a number of monitoring runoff water quality sampling, and select the two rainfall over the whole process of test results. Combined with rainfall data, analysis of rainfall runoff, runoff, pollution characteristics, and runoff on receiving water quality impacts. Sub-test of the main pollutants in runoff water, the type and concentration of various water quality of rainfall runoff correlation between the biodegradability was analyzed. Combination of foreign research data to explore the way the land interest, rainfall conditions, the nature of the road sediment runoff pollutant concentrations and other factors on the impact of road runoff of pollutants and erosion model for application of the law. Through theoretical analysis, identify pollution load calculation method and the mathematical model to study surface water runoff on the receiving water quality impact of the effective methods. Situation on the ground combined with the old city of Hefei, the final sum up corresponding strategies and methods.Through this research, in the control of rainfall runoff pollution, the results obtained are as follows:①Engineering measures:vegetation control, wet detention pond, filtration systems, wetlands and other measures of rational use and combination of effective control of runoff pollution is the primary means②non-engineering measures:that city environmental management, road cleaning,todevelop rules and regulations and other measures to support the use of engineering measures, engineering measures can be used as an effective supplement combination③Hefei present great development and construction of ecological situation and building livable city goals in engineering design and building of appropriate use of new technology and new technologies, such as permeable paving, and can save cooling tower technologies such as ground source heat pump.④The study Hefei management can improve environmental protection, environmental planning, preparation of urban construction projects environment’s impact point source the basis of the information.