Urban Runoff Modeling and Prediction

This chapter attempts to develop an integrated approach of remote sensing and geographic information systems for examining the effects of urban growth on surface runoff at local level by using the Zhujiang Delta of South China as a case. The model used for estimating surface runoff in the chapter was developed by the United States Soil Conservation Service. It has been widely applied to estimate storm runoff depth for every patch within a watershed based on runoff curve numbers (CN). The chapter summarizes a method to estimate composite CN which was developed with the vegetation–impervious surface–soil model, normalized difference vegetation index (NDVI), and soil types. First, soil types and NDVI are classified into several classes, respectively. Second, each class of soil type and NDVI are given an initial CN of soil and initial CN of vegetation, respectively. Lastly, the CN is calculated by computing the percentages of impervious surface, NDVI class, and soil class.