The federal Clean Water Act requires that states and tribes restore and maintain the chemical, physical, and biological integrity of the nation's waters. States and tribes must adopt water quality standards necessary to protect fish, shellfish, and wildlife while providing for recreation in and on the waters whenever possible.

This document describes the nine water bodies and 19 pollutants listed on the 1998 §303(d) list. Two additional pollutant-water body combinations are also assessed. Sediment is the most common listed pollutant in the subbasin; it was a listed pollutant on all 1998 §303(d) listed water bodies within the subbasin.

In general, the water quality of the Bruneau River is very good. Limited impacts have occurred in the upstream watersheds. Concentrations of suspended materials are very low throughout the subbasin. However, on a seasonal basis, the Bruneau River and other surface water bodies exceed state water quality standards for excessive nutrients, temperature, and/or other pollutants. The temperature exceedances may be due to the influence of the thermal spring waters. These waters form the principle habitat for the endangered Bruneau Hot Springsnail.

Nutrients are a listed pollutant in the Bruneau River and Jacks Creek segments of the Bruneau River Subbasin. In these reaches it was determined that total phosphorus can be a limiting nutrient and that all nutrients may be in excess of recommendations.

The other listed streams and pollutants in the subbasin, in general, were well below any standard or guideline established for the protection of beneficial uses or were dry for all, or a majority of, the year. It was determined that three of the listed water bodies should not have been considered water bodies which would have supported beneficial uses and were therefore listed in error.

Bruneau River, Jacks Creek, Wickahoney Creek, and Hot Creek are listed for flow alteration. The U.S. Environmental Protection Agency does not believe that flow alteration is a pollutant as defined by the Clean Water Act. Since TMDLs are not required for water bodies impaired by pollution but not pollutants, TMDLs were not developed for flow alteration.

Temperature is a minor problem in some segments of the Bruneau River Subbasin. However, this is generally considered by the residents of the Bruneau area to be a natural problem. Additionally, in other areas of the state bioassessment data conflict with temperature information and water quality standards. This is likely the result of the state's water quality standards being derived from an outdated understanding of cold water biota's temperature requirements. DEQ is participating in a regional review of temperature criteria. Following the conclusion of the temperature review, temperature exceedances in the Bruneau River Subbasin will be reassessed and, if needed, a temperature TMDL will be completed.