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Beavers and the dams they build promote sediment deposition and modify channel and floodplain morphology and physical complexity. Beaver activities may result in increased watershed-scale water and sediment retention, but few studies have considered beaver impacts to sediment across larger spatial extents. There has been increased interest in investigating beaver reintroduction as a nature-based solution to sediment management due to their increased distributed storage upstream of reservoirs. Although the effects of beaver dams on stream morphology and restoration have been studied at the pond and reach scale, research on the effects of beaver dams at the watershed scale is still lacking. In addition, few studies have successfully incorporated beaver dams into hydrologic and hydraulic models that could be used to extend field data and inform watershed scale sediment dynamics. We collected field data on 27 beaver ponds and associated dams in the central Rocky Mountains in Colorado, USA to assess sedimentation dynamics and model watershed sediment yield. Field measurements included mean sediment depth in ponds, grain size distribution of deposited sediment, dam dimensions and hydraulic measurements to determine energy loss resulting from beaver dams. We will use our field measurements to calibrate and validate SRH-2D, a watershed scale numerical model that has been modified to capture beaver dam impacts on sedimentation and sediment yield. Modeled scenarios will include an increase of beaver dam density within the watershed and an associated assessment of how much increased beaver dam density modifies sediment delivered into the Paonia Reservoir, located downstream of the modeled watershed. Preliminary results indicate that channels with beaver ponds can store substantial volumes of sediment compared to channels without beaver ponds. Modeling the watershed-scale effects of beaver activity will inform the potential for beaver to serve as a nature-based solution to reservoir sediment management. Our results will also further our understanding of how beaver removal and population reductions have influenced watershed sediment dynamics.