Testing of the SPUR Hydrology Component on Rangeland Watersheds in Southwest Idaho

ABSTRACT THE hydrology and sediment yield components of the SPUR (Simulation of Production and Utilization of Rangelands) model are applied to three source basins of the Reynolds Creek Experimental Watershed in southwest Idaho. Calibration with observed streamflow gave coefficients of determination, R2, of 0.63, 0.67, and 0.85 for monthly runoff volumes at Murphy Creek, Upper Sheep Creek, and Reynolds Mountain East watersheds, respectively. The timing of monthly runoff volume was reasonably accurate. Insufficient information was available to calibrate the snow accumulation and melt routines. The parameter sets for these routines were very consistent between watersheds despite the different snow accumulation and melt patterns on the watersheds. Sediment yield predictions were poor, and indicated a need for further investigation of models applicable to these steep, rough mountain channels.