Salt River Subbasin

Sediment, bacteria, habitat modifications, and selenium are stressors affecting beneficial uses in the subbasin. Much of the basin is grazed by livestock on US Forest Service, Bureau of Land Management (BLM), and private lands. This activity can impact streams by destabilizing banks, reducing riparian vegetation, and widening the stream channel. Livestock grazing can also impact the beneficial use of contact recreation by increasing bacterial concentrations in streams. The Salt River subbasin contains historic and active phosphate mines. Waste rock dumps and open pits have the potential to pollute nearby water and impact beneficial uses of aquatic life. Other suspected stressors include erosion caused by recreation and roads. Assessments identified sediment as the pollutant source in 16 assessment units (AUs) in the subbasin, and TMDLs were developed for each of these AUs. In the Salt River subbasin, excess sediment is primarily the result of bank erosion initiated by livestock grazing on public and private lands. Nonpoint sources of E. coli in the subbasin include feces of livestock and wildlife. TMDLs were developed for 5 AUs impaired by bacteria. Selenium listings are not addressed as part of this subbasin assessment and TMDL. Rather, these listings are being addressed under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), a mine reclamation program.