Quality monitoring and property analysis of urban initial rainwater

Pollutants of urban rainwater runoff on water environment as well as the influencing factors are reviewed. By comparing with combined sewer overflows (CSOs), the paper thinks that urban rainwater runoff pollution control is necessary. Four months road runoff and Combined Sewer Overflows quality monitoring was carried in Luoyang, where indices included suspended solids( SS), chemical oxygen demand(CODcr), dissolved chemical oxygen demand, Ammonia nitrogen(NH3 - N) and total phosphorus(TP).The results showed that the concentrations of pollutants of CSOs were higher than that of street runoff. Concentrations of pollutants in initial flush were very high, but they descended gradually and approached to the stabilization after a period of flushing. The main pollutants were SS,COD, and NH3 - N. By analyzing the correlation between SS and CODcr and contrasting the content between total CODcr and dissolved CODcr, it inferred that SS was the main contribution to CODcr.The initial split-flow is suggested to handle the heavily polluted runoff.