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The Colorado River (COR) watershed includes a variety of areas with saline geologic and soil materials. International concerns over the salt load of the river began when salinity levels in COR water flowing into Mexico peaked in the 1960s. This sparked ongoing debate and various efforts at salinity abatement ensued by a variety of stakeholders. We looked at potential salinity sources due to eroding soils in the COR watershed above Lake Mead. New predictive soil mapping techniques along with remotely sensed landcover metrics were used to estimate erosion in areas with saline soils at a field scale (30m grid). Initial results show salinity hotspots near Vernal and Price, UT, Delta, CO and areas near Lake Mead, NV. The Unit Stream Power Erosion and Deposition model (USPED) was employed to estimate modern soil erosion rates to overlay onto salinity maps. Erosion models suggest the more rugged areas on the margins of these saline areas could be significant sources of salinity into COR. Surprisingly, initial results also suggest some higher mountain basins as a potentially significant salinity source. These mapping results will be validated with field assessments and by spatio-temporal comparison to different electrical conductivity measurements made on river locations in the basin. Project goals include a potential salt contribution map prioritized by a hydrological distance from surface waters within the basin. These maps and analysis are being made to aid land managers in targeting restoration and determining sound policies for land use while helping deliver high quality water down to lower COR water users.