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.

Section 303(d) of the Clean Water Act establishes requirements for states and tribes to identify and prioritize water bodies that are water quality limited (i.e., water bodies that do not meet water quality standards). States and tribes must periodically publish a priority list of impaired waters, currently every two years. For waters identified on this list, states and tribes must develop water quality improvement plans known as total maximum daily loads (TMDLs) that establish allowable pollutant loads set at levels to achieve water quality standards.

The Bear River spans over 550 miles, draining a 470,000-acre watershed that encompasses parts of Utah, Wyoming, and Idaho. The river begins and ends in Utah. This document addresses only the Idaho portion of the Bear River and its Idaho tributaries.

Thirty-nine stream segments in the Bear River Basin were listed on the Idaho 1998 §303(d) list. Several streams in the Bear River Basin enter Utah from Idaho and thus must comply with any TMDLs established by Utah. The recommended pollutant targets in this document match or exceed state of Utah targets for those streams.

Historically, Bear River water bodies sustained several beneficial uses. Current information suggests some beneficial uses, such as cold water aquatic life and salmonid spawning, are impaired and are not fully supported in several subbasin streams.

Several potential sources of pollutants have been identified in the Bear River Basin, including agriculture, livestock grazing, changes in the natural hydrograph (e.g., water diversion), degraded stream channels and banks, roads, mining, recreation, mass wasting (e.g., landslides), and wastewater treatment plants.

Data indicate North, St. Charles, and Maple Creeks are meeting their beneficial uses for cold water aquatic life. It is recommended that North and St. Charles Creeks be removed from future §303(d) lists. Although Maple Creek supports cold water aquatic life, it has high levels of bacteria so a bacteria TMDL was developed. Meadow and Samaria Creeks are intermittent streams with optimum flows less than one cubic foot per second; it is suggested that these streams be removed from future §303(d) lists.

TMDLs were not developed for Dry Creek, Preuss Creek, Snowslide Canyon, Co-Op Creek, Strawberry Creek, and Dairy Creek due to a lack of data. Data sufficient to develop load analyses for each of these streams should be collected in 2006 for completion of a TMDL in 2007.

Several stream segments are listed for flow or habitat alteration. The EPA considers certain unnatural conditions such as flow and habitat alteration, that do not result from the discharge of specific pollutants, as "pollution." TMDLs are not required for water bodies impaired by pollution, but not specific pollutants; therefore, TMDLs were not established for flow or habitat alteration.

Data imply there are other (un-listed) water bodies with impaired beneficial uses due to high levels of phosphorus and suspended solids. TMDLs were prepared for some of these streams and others are recommended for inclusion on future §303(d) lists.