Integration of Gleams and WEPP Sediment Models Into RZWQM and Applied to Experimental Datasets.

Efficiently crafting agricultural best management practices that minimize non-point source pollution of waterways necessitates a computer model that can accurately track sediment movement off field as well as the decay of sediment sorbed chemicals. This project merged sedimentation code from both the Groundwater Loading Effects of Agricultural Management Systems (GLEAMS) and the Water Erosion Prediction Project (WEPP) into the Root Zone Water Quality (RZWQM) vadose zone model. These two sediment models were then compared both against each other and reality using data from multiple field studies: two Alfalfa fields in Northern California, rangeland at the Central Plains Experimental Range (CPER) in Northern Colorado, and unplanted bare soil plots with and without detritus in Ft. Collins CO. Results from the field tests and modeling runs will be presented, compared, and analyzed to determine which is the best sedimentation module for field scale modeling.