Floodplain Delineation of Unsteady Flow Using HEC-RAS Progress Report Presented By: Kevin Donnelly

Study Area The Colorado River between Wirtz Dam and Inks Dam (Lake LBJ) and its two major tributaries, Sandy Creek and the Llano River Lake LBJ is 21.15 miles long and 10,800 feet wide at its widest point. The lake covers 6,375 acres, and its capacity is 138,500 acre-feet. Inks Dam

Objectives Develop a terrain model combining 30-meter DEM data, 2-foot contours, and UNET cross sections Develop new cross sections along the Colorado River (Lake LBJ), Llano River, and Sandy Creek using GeoRAS Simulate flooding that occurred in November 2000 Import resulting water surface profiles back into GIS were the spatial extent of the flooding can be better seen and understood

Input Data

Intermediate Data

Results

Questions