Hydrology for urban land planning - A guidebook on the hydrologic effects of urban land use

This circular attempts to summarize existing knowledge of the effects of urbanization on hydrologic factors. It also attempts to express this knowledge in terms that the planner can use to test alternatives during the planning process. Because the available data used in this report are applied to a portion of the Brandywine Creek basin in Pennsylvania, this can be considered as a report on the basic hydrologic conditions of the Brandywine Creek basin prior to the beginning of major urbanization. Because the available data are not yet adequate, this report can be considered as a compilation of tentative suggestions in the form of an explanatory, not a definitive handbook. The application of current knowledge of the hydrologic effects of urbanization to the Brandywine should be viewed as a forecast of conditions which may be expected as urbanization proceeds. By making such forecasts in advance of actual urban development, the methods can be tested, data can be extended, and procedures improved as verification becomes possible.