Water Quality of Urban Runoff from Different Rainwater Harvesting Surfaces

摘要

The rainwater harvesting,as an alternative to solve the problem of water shortage,is playing a very important role in dry area,such as capital city Beijing.In this paper,we investigated the water quality of runoff from four different rain harvesting surfaces.The results show that the main contaminants in runoff are organic compounds and suspended solids.During investigation period,the concentration of NH3- N from the roof surface was beneath the criteria of class V.The COD concentration from the road surface was more than 493.5mg/L,at the initial stage of the runoff,furthermore,decreasing with rainfall duration.In a conclusion,runoff from roofs can be reused in accordance with the national standard of water reuse,except the initial runoff.Runoff from road surface cannot be used directly.