Abstract
The development and validation of a methodological approach to predicting runoff over large regions is considered. The Soil Conservation Service (SCS) runoff curve number procedure is modified to allow for areal variation of land use and land cover, soils, and rainfall over a regular‐gridded network. Ten rainfall events, from the period 1973–1980, are selected to estimate runoff for the Mahantango Creek Watershed (421km2) in east‐central Pennsylvania. The method may be useful in generating a geographic information system database for distributed‐components hydrologic models and for water resources management.