ABSTRACT:

This is and HEC-HMS model for direct runoff in a watershed in the Rivanna River basin created for a graduate course in Hydrology at the University of Virginia. This watershed was delineated in ArcGIS using the USGS discharge gage 01665500 as the pour point. Runoff was modeled using the SCS curve number method. CN was estimated using land use data in ArcGIS. Transform method used was the SCS unit hydrograph. The basin was subdivided into three subbasins which were routed using the Muskingum routing method. Parameters for the Mukingum method were determined using ArcGIS. The model was calibrated to a storm occurring on 29 December 2013 and verified using a second storm occurring on 25 January 2003. The Nash-Sutcliffe goodness of fit value for the verification storm was determined to be 0.825.