Unit hydrograph development for watersheds in Fort Worth, Texas

For most of hydraulic designs at a specific location within a system having the hydrometerological characteristics, it is necessary to develop a hydrograph at that particular location. A widely accepted method is the "unit hydrograph" (UH) theory proposed by "Sherman" (1932) that has become an important tool for hydrologists. The unit hydrograph is the unit (1 inch rainfall excess) pulse response function of a linear hydrologic system. In this study, the rainfall and runoff data for the USGS stations in the Fort Worth, Texas region are converted from paper reports into electronic files are processed using several FORTRAN programs. Five events for every USGS station in the Fort Worth area are selected. Linear programming (LP) formulations and least square methods that minimizes the error between observed and estimated direct runoff hydrograph are used to develop UH and Gamma UH fitting. The resulting UHs are represented as graphs with error analysis. Error analysis indicates how well developed UH can be used to regenerate direct runoff hydrographs (DRHs) for all the event in watershed. Best UH and synthetic Gamma UH are developed for each watershed. Suggestions for further studies are provided.