U.S. Department of Agriculture: Forest Service -- National Agroforestry Center


Date of this Version

April 2008


Written for presentation at the 2008 Mid-Central Meeting. Sponsored by ASABE. Lincoln, Nebraska. April 4 - 5, 2008.


The watershed version of WEPP (Water Erosion Prediction Project) was used to estimate 50-year runoff and sediment yields for a 291 ha watershed in eastern Nebraska that is 90% terraced and which has no historical gage data. The watershed has a complex matrix of elements, including terraced and non-terraced subwatersheds, multiple combinations of soils and land management, a grassed-waterway network, and natural stream channels leading to the outlet. The objectives of this study were to model the study watershed using WEPP and to evaluate model results compared to literature values. WEPP estimated the sediment yield to be 1.9 T/ha/yr, the sediment delivery ratio to be 0.22 and the percent of sediment contribution from the main channel to be 31% of the total sediment yield. These results are consistent with values reported in the literature.