Abstract:When hydraulic design decisions are made in a watershed, engineers rely on estimation of the design discharge. Historically, they have applied empirical methods to do this, but empirical methods can only describe the hydrologic characteristics of the watersheds from which they were derived. Although more advanced methods now exist, engineers find them challenging to use because of the abundant data needed and intensive data analyses. In this study, we make the more advanced hydrological analysis methods simpler to use by linking them with DEM terrain analyses in a GIS platform. The system provides hydrologic and geomorphic information needed to create a design discharge at any location in a watershed. Since the system allows users to test several locations of subwatershed outlets, it is convenient for them to examine different aspects for engineering alternatives.