Temporal-spatial distribution and First Flush Effect of precipitation runoff pollution in Kunming urban area after the once-in-a-century drought

Sampling and monitoring of road and roof runoff at Xuefu Road catchment in Kunming City were carried out during the period from March to April 2010, to study the temporal-spatial distribution and first flush effect of precipitation runoff pollution. It was found that it was not quite obvious that the concentration of contaminants decreased with the increasing of flow time. The pollution of the runoff formed on March, 27th was most serious, yet on March, 28th was lightest. Road runoff had much greater pollution intensity than roof runoff. With regard to the 5 water quality parameters monitored, the 3 rains all led to obvious First Flush Effect.