|Hydrologic Unit Code
|1,133 square miles (725,120 acres)
Water Bodies with EPA-Approved TMDLs (Category 4a)
Badger Creek, Darby Creek, Fox Creek, Mahogany Creek, Moody Creek, North Fork Teton River, Packsaddle Creek, South Leigh Creek, Spring Creek, Teton River and tributaries
|Beneficial Uses Affected
|Cold water aquatic life, salmonid spawning
|Major Land Uses
|Date Approved by EPA
|Date Supplement Approved by EPA
|Date Approved by EPA
The Teton River subbasin is one of three watersheds that comprise the Henrys Fork Basin. The Teton River drains an area of 806 square miles in Idaho and 327 square miles in Wyoming. The river originates from headwater streams in the Teton, Big Hole, and Snake River Mountain Ranges and flows more than 64 miles to where it discharges to the Henrys Fork River.
Teton Canyon contains the river for approximately 17 miles. In 1975, Teton Dam was completed at the lower end of the canyon to create a reservoir for irrigation water. In June 1976, when the reservoir behind the dam had almost filled, the earthen dam collapsed. More than 250,000 acre-feet of water and 4 million cubic yards of embankment material flowed through the breach in less than 6 hours. The portion of the river below the dam was extensively altered by the flood and by the mitigation and restoration work that followed. However, the quality of water in the Teton River subbasin is generally good.
2003 Subbasin Assessment and TMDL
Of the 13 segments (11 streams/rivers) in the subbasin on Idaho’s 1998 §303(d) list, sediment is cited as the pollutant responsible for the impairment of 9 segments. Agriculture is the main contributor of sediment. The other pollutants shown on the 1998 §303(d) list are also associated primarily with agriculture.
Sediment TMDLs were developed for 8 water bodies and nutrient TMDLs for 2 in the original TMDL. Temperature TMDLs for Fox and Spring Creeks and a nutrient TMDL for Moody Creek were developed in the TMDL supplement. Sediment allocations for North Leigh Creek were included in the Spring Creek sediment TMDL.
Darby, Fox, Horseshoe, Packsaddle, and Spring Creeks are listed for flow alteration, and the Teton River is listed for habitat alteration. However , the US Environmental Protection Agency does not believe that flow and habitat alteration are pollutants 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 or habitat alteration.
2003 TMDL and Supplement: Streams and Pollutants for Which TMDLs Were Develope
|South Leigh Creek
|Sediment, nutrients (total phosphorus)
|North Fork Teton River
|Sediment, nutrients (total phosphorus and nitrate)
- Teton River Subbasin Assessment and Total Maximum Daily Load (January 2003)
- Supplement to the Teton River Total Maximum Daily Load Moody, Fox, and Spring Creeks (June 2003)
- Teton Subbasin Total Maximum Daily Load Implementation Plan for Agriculture (April 2005; Revised February 2014)
- Teton River Subbasin: 2016 Total Daily Maximum Daily Loads and Five-Year Review (October 2016)
- Teton River Subbasin TMDL Agriculture Implementation Plan (September 2020)