Protecting Public Health and the Environment.

Medicine Lodge Creek Subbasin

Subbasin at a Glance

Hydrologic Unit Code 17040215
Size 872 square miles (558,080 acres)

Water Bodies with EPA-Approved TMDLs (Category 4a)

Crooked Creek, Deep Creek, Edie Creek, Fritz Creek, Horse Creek, Indian Creek, Irving Creek, Medicine Lodge Creek, Middle Creek, Warm Creek, Warm Springs Creek, Webber Creek

Beneficial Uses Affected Cold water aquatic life, salmonid spawning, primary and secondary contact recreation, domestic water supply
Major Land Uses Grazing, irrigated agriculture, dryland farming
Date Approved by EPA May 2003
Approval Letter
Date 2016 Addendum Approved by EPA January 2017
Approval Letter

Subbasin Characteristics

The Medicine Lodge Creek subbasin is located in southeastern Idaho and borders Montana to the north. The northern half of the subbasin is rural and occupied by about one person per every two acres. The southern half of the subbasin has a higher population, but does not contain any of the flowing streams of the Medicine Lodge Creek subbasin.

2003 Subbasin Assessment and TMDL

This document assesses the §303(d)-listed stream segments in the Medicine Lodge Creek subbasin as well as several other streams. Medicine Lodge Creek sinks and is diverted very soon after the town of Small, Idaho. Crooked Creek, Warm Springs Creek, and Deep Creek flow independently in drainages to the west of Medicine Lodge Creek. These streams also sink before reaching other water bodies.

Three species of salmonids have been documented in the watershed. Rainbow Trout, Brook Trout, and Yellowstone Cutthroat Trout are all found throughout Medicine Lodge Creek and its tributaries. The Yellowstone Cutthroat Trout is a state sensitive species and is carefully managed by the Idaho Department of Fish and Game. Warm Springs Creek contains some warmwater species of fish. Salmonid spawning is an existing use for streams within the Medicine Lodge Creek subbasin, except for Warm Springs Creek, Divide Creek, Deep Creek, and the lower portion of Medicine Lodge Creek.

DEQ has collected data throughout the subbasin and has determined that sediment and temperature are the primary pollutants of concern. Instream sediment targets have been identified from literature values that are supportive of salmonid spawning and cold water aquatic life. These target values will be used to track the progress of streambank recovery and determine the need for additional management practices to improve water quality.

Sediment TMDLs were written for Medicine Lodge Creek, Irving Creek, and Edie Creek. Temperature TMDLs have been developed for 11 streams. Nutrient TMDLs will not be written for the streams in the Medicine Lodge Creek subbasin since no data indicate nutrient enrichment in any part of the watershed.

Edie and Irving Creeks are listed for habitat alteration, and Medicine Lodge Creek is listed for flow alteration. The US Environmental Protection Agency does not consider habitat or flow alteration as 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 habitat or flow alteration.

2003 TMDL: Streams and Pollutants for Which TMDLs Were Developed

Medicine Lodge Creek
Temperature, sediment
Fritz Creek
Temperature
Irving Creek
Temperature, sediment
Crooked Creek
Temperature
Deep Creek
Temperature
Edie Creek
Temperature, sediment
Horse Creek
Temperature
Indian Creek
Temperature
Middle Creek
Temperature
Warm Creek
Temperature
Webber Creek
Temperature

2016 Addendum TMDL

The Medicine Lodge Creek Subbasin is located in eastern Idaho south of the Beaverhead Mountains of the Continental Divide. It is a closed basin with no surface water exiting its boundaries. The U.S. Environmental Protection Agency approved the original Medicine Lodge Subbasin Assessment and TMDLs (hydrologic unit code [HUC] 17040215) in May 2003. Ten AUs were impaired by sediment, including Medicine Lodge, Edie, Irving, Warm Springs, and Crooked Creeks. Temperature impairment was identified in Medicine Lodge, Indian, Middle, Irving, Warm, Horse, Fritz, Webber, Edie, Deep, and Crooked Creeks, incorporating 22 AUs. Due to additional assessments since the original TMDL and heritage issues with the Idaho Department of Environmental Quality (DEQ) assessment database, the 2012 Integrated Report listed 14 AUs in Category 5 for bacteria, sediment, and combined biota/habitat bioassessments. Only two of these AUs are addressed with new E. coli TMDLs in this document. Two other AUs that were previously unlisted for E. coli, also received new E. coli TMDLs because of new monitoring. The remaining temperature TMDLs in this document are revisions of previously approved temperature TMDLs found in Category 4a of the 2012 Integrated Report; temperature TMDLs that have been revised using the potential natural vegetation (PNV) methodology using shade surrogates as TMDL targets.

2016 TMDL: Streams and Pollutants for Which TMDLs Were Developed

Medicine Lodge Creek
Temperature, E. coli
Indian Creek
Temperature
West Fork Indian Creek
E. coli
Middle Creek
Temperature, E. coli
Edie Creek
Temperature
Irving Creek
Temperature
Warm Creek
Temperature, E. coli
Horse Creek
Temperature
Fritz Creek
Temperature
Webber Creek
Temperature
Deep Creek
Temperature
Crooked Creek
Temperature

Subbasin Documents


Staff Contacts

Water Quality Manager
Troy Saffle
DEQ Idaho Falls Regional Office
900 N. Skyline Drive, Suite B
Idaho Falls, ID 83402
(208) 528-2650
troy.saffle@deq.idaho.gov