An Evaluation of Real-Time Streamflow Forecasts From a Distributed, Physically Based, Hydrologic Model Applied in the Upper Rio Grande Basin.

Different uses compete for the water resources of the Upper Rio Grande Basin including agriculture, municipalities, industry, recreation, ecology and water quality. For water operations management in the Upper Rio Grande, resource managers rely on accurate forecasts (both short and long term) of streamflow at several locations, or nodes on the river. In this study, the USGS Precipitation Runoff Modeling System (PRMS) is used to predict quantity of runoff in the headwater basin above the USGS streamflow gage near Del Norte, Colorado. Because fine-tuning of the PRMS can result in improved forecasts, predictions were made using three adaptations of the model: 1) low-spatial resolution, 2) high-spatial resolution, 3) using an alternate method of distributing climate variables throughout the basin. A post-forecast evaluation of the real-time streamflow forecasts is made via comparisons with forecasts made by the National Resources Conservation Service (NRCS). This study is highly collaborative between researchers at the Desert Research Institute (DRI) and the USGS as part of the NSF funded Center for Sustainability of semi-Arid Hydrology and Riparian Areas (SAHRA) efforts to improve models of snow distribution and snowmelt processes.