Study On Characteristics Of Non-point Source Pollution On Roads In Longgang District,SZ

Non-point source pollution of urban roads has become the most important factor of urban pollution.Compared with ordinary roads,urban roads are in a relatively closed state,and heavy traffic pressures have polluted urban roads seriously.In order to realize the control and utilization of non-point source runoff from urban roads.The pollution characteristics of road flow and the factors affecting the water quality of rainfall runoff in urban roads were analyzed and the self-made rainwater filtering device was used to verify the correlation between pollutants based on the water quality analysis.Because the change regulation of non-point source pollution of urban roads varies from city to city,and the conclusions cannot be shared.The research of rainfall runoff pollution in a specific city is extremely important.Based on this concept,this article selects the industrial area,residential area,municipal road,and village road in Longgang District of SZ City as the research objects.Based on the theoretical analysis and experimental research,the following conclusions are obtained:The particle size of the studied road is mainly concentrated in the range of0.125-2.36mm,and the overall distribution is normal.In the initial stage,the rainwater pollution is relatively serious,the water quality is generally higher than Class V water quality standard of surface water,and exceeds the reuse index,so it can not be directly used as reuse water.The concentration indicators of SS,COD,NH₃-N,TN,and TP in urban road rainwater runoff are relatively high.Among them,SS and COD are the most serious,and the initial concentration is the highest.In the control of urban road non-point source pollution,we should focus on SS and COD.Different types of urban underlays have a greater impact on the quality of runoff.Rainfall interval days directly affect the level of initial pollutant concentration The type of rainfall is the main factor for the change of pollutant concentration in runoff.Analysis between the concentrations of pollutants shows that the SS has a high correlation with COD and TP,and the correlation between SS and COD is more than the SS and TP,the correlation between SS and TN is not obvious,because the total nitrogen is dissolved in water According to the analysis of different types of underlying surfaces of urban roads,the correlation between pollutants in municipal roads and industrial areas is higher than that in urban villages and residential areas.due to the different sources and concentrations of pollutants.A physical filtration experiment was performed on rainwater using a filter layer composed of pebbles,gravel,and quartz sand.Experimental results show that while the SS in the runoff is removed,it will also have a certain effect on the removal of COD and TP,but the removal effect of NH₃-N and TN is poor.