Abstract |
A model of surface runoff as a function of land surface characteristics in an urban residential area was developed from measured land surface characteristics, precipitation, and runoff data. Surface runoff from impervious surfaces feeding directly into drainage ways began after an initial extraction for wetting the surface of .03 inches (.08 inches after hot, sunny summer weather). The model was used to evaluate the effects of urbanization on other components of the hydrologic cycle by incorporation into a standard daily water budget run for Shellpot Creek Watershed, Wilmington, DE for 1954 to 1968. The application revealed a tripling of surface runoff, a one-half increase in total runoff, and a halving of both percolate to ground water and actual evapotranspiration as urbanized surface (residential use, 54 percent impervious surface) increased from 20 to 100 percent of the watershed area. |