According to the water quantity balance equation,the rainfall and evaporation from the surface of the lake is analyzed,seepage quantity from vertical and horizontal sides of the lake is calculated with Darcy s Law,and the rain runoff discharging into Mengze Lake from the surrounding area is calculated also.

The current status of rainwater utilization in cities of our country,as well as the quality of rainwater runoff and influence factors thereof were summarized;the characteristics of direct and indirect ways for rainwater utilization were compared;meanwhile,the key poi.

Taking the rainwater engineering in Beifang Garden District in Fuxin City of northeast China as a case to study,the pollution situation and the quality characteristics of rainwater runoff were obtained by monitoring the rainwater samples from the roof and road in different rainfall intensity.

The quality and major influential factors of runoff in Beijing urban area;

Characterization of contaminated runoff on free way surface.;

Partitioning fraction of organic pollutants in expressway stormwater runoff

Pollution of city rainfall runoff and its controlling measures;

The necessity for evaluation of the pollution load carried by stormwater runoff in the city drainage system plan was analyzed.

In the process of urbanization in Nanjing,the construction of the city makes the original soil surface be covered by impermeable pavement increasingly,inducing series urban environmental problems,the most remarkable one of which is the aggravation of stormwater runoff as a result of the runoff coefficient increasing.