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The ability to accurately estimate the extent and spatial distribution of soil erosion and sediment deposition can be critical for determining the consequences of land management practices, and for predicting if, where, and the extent of ameliorative practices that may be needed when current land uses have resulted in significant land degradation. Unfortunately, most models have historically under- or over-estimated soil erosion and sediment deposition, particularly when applied to non-cultivated lands such as rangeland. Built on the backbone of the Universal Soil Loss Equation (USLE), the Unit Stream Power Erosion and Deposition (USPED) model was developed originally for the U.S. Department of Defense. It overcomes many of the deficiencies of most other models. In particular, it alters the manner in which topography is considered. It accounts for 3-dimensional topographic complexity, such as the convergence and divergence of slopes, rather than treating landscapes as a series of simple planes. Digital elevation models (DEM) are used to compute the contribution of topography. The model operates in a variety of geographic information systems (GIS) and at any spatial resolution. Estimates of erosion and deposition are made for each pixel in the 3-dimensional landscape. The model utilizes published databases for many of the model parameters. We use satellite imagery to spatially determine the contribution of vegetative cover. The USPED spatially estimates both erosion and deposition as a change in sediment transport capacity across each grid cell. Limited field work is required only to validate model components and results.