Projects > Sediment Modeling Shields, Jefferson, Big Hole, Tobacco River, Missouri-Cascade, and Lower Clark Fork Watersheds


Confluence has worked with several watershed groups and the Montana Department of Environmental Quality to predict sediment delivery to streams and rivers via Universal Soil Loss Equation (USLE) sediment models. This work has been used to characterize sediment loads and to establish potential load reductions for DEQ’s watershed planning process.

The models Confluence have developed are GIS-based implementations of the (R)USLE sediment loss equation. The original field-scale model was expanded to the watershed scale use through the application of GIS grid cell based calculation methods. Sediment load was then rendered from the USLE soil loss calculation through the use of an appropriate sediment delivery ratio (SDR). The model is implemented using ArcView GIS v 9.2 tools, and the results datasets are project, grid, and shapefile formats.