Study on initial flushing effect of two new permeable pavements

Abstract

ABSTRACT Due to the initial flushing effect, many pollutants are carried in runoff in the early stage of rainfall, which is an important source of water quality degradation in urban receiving water bodies. In this paper, the initial flushing effect on two new permeable pavements (perforated pipe and gravel pipe) in an area of low-permeability clay is studied through parameter fitting, calculation and comparison. Compared with ordinary pavement and conventional permeable pavement, the initial flushing effects of runoff pollutants on different pavements were tested and simulated. Results indicated that the initial flushing intensity of the two new water-permeable pavements (perforated pipe and gravel pipe) was weaker and similar in process; each showed good control on runoff water quantity and water quality, which can better control the initial flushing intensity of rainwater. Therefore, the two new water-permeable pavements (perforated pipe and gravel pipe) can be well applied to areas of low-permeability clay and effectively relieve high initial pollutant concentration in runoff, thus reducing pollution in the surrounding environment.