Water Quality Improvement Project
Hangman Creek Area:


The Hangman Creek (also known as Latah Creek) watershed drains approximately 431,000 acres and spans across two states and four counties. More than 60 percent of the watershed resides in eastern Washington State (WRIA 56) while the remaining portion, including the headwaters, originates in the western foothills of the Rocky Mountains near Sanders, Idaho. The major tributaries to Hangman Creek are Marshall Creek; California Creek; Spangle Creek; Rock Creek; Rattler Run Creek; and the Little Hangman Creek.

Water quality issues

Streams in the Hangman Creek watershed currently do not meet Washington state’s water quality standards for several reasons. Land use influences, (agriculture, impervious surfaces, timber harvest, roads, etc.) as well as stream channel and flood plain alterations over the last 100-years have contributed to “flashy” flow conditions, unstable stream banks, and substandard water quality.

Hangman Creek is also a majority tributary to the Spokane River. Ecology developed a plan to address low oxygen and high nutrients (phosphorus) in the Spokane River and Lake Spokane (Long Lake). Hangman Creek's contribution of nutrients and sediment to the Spokane River is important to this process. Efforts to reduce nutrients, especially phosphorus, in the Hangman Creek watershed will be necessary to address water quality issues in the Spokane River and Lake Spokane.


Status of the project

To address the water quality problems in the Washington portion of the watershed, Ecology and the Spokane County Conservation District worked together on a project called a Total Maximum Daily Load (TMDL). A TMDL, also known as a water quality improvement plan, is a common-sense, science-based approach to cleaning up polluted water so that it meets water quality standards. TMDLs established today also can help manage water quality on a watershed scale to prevent the loss of beneficial uses in the future. Beneficial uses can include irrigation, fishing, habitat, recreation (swimming, wading, and boating) and other uses.

In 2004, the Spokane County Conservation District (SCCD) applied for and was awarded a grant to develop the water quality improvement report or total maximum daily load (TMDL) for the Hangman Creek watershed. Since then, the SCCD and Ecology have worked together to study the watershed, work with the local community, and develop the improvement report. This effort addresses high levels of fecal coliform bacteria, high water temperatures, and high turbidity.

In 2004-2005, SCCD conducted monitoring to fill the data gaps needed to complete the TMDL analysis. The SCCD also formed a watershed advisory group to work on strategies to reduce the amount of pollution reaching the streams. The advisory group consists of people representing many different interests in the watershed, including agriculture; forestry; livestock production; and entities such as Spokane County; the city of Spokane; and the Coeur d’Alene Tribe. The advisory group met regularly to work on the water quality improvement plan (TMDL).

Ecology published the water quality improvement report for fecal coliform bacteria, high water temperatures, and turbidity in the Spring of 2009. Ecology and the SCCD reviewed all comments, revised the report, and published the final report in June 2009. The Environmental Protection Agency approved the report on September 29, 2009.

After EPA approval of the TMDL, Ecology and the SCCD worked with agencies and organizations to develop an implementation plan outlining what needs to occur to meet water quality targets in the watershed and various commitments to the effort. The draft implementation plan was available for public review and comment from February 15 to March 18, 2011. After addressing the comments received, Ecology published the final plan and sent a copy to EPA on May 13, 2011.

In November 2013, various implementing partners met to discuss the status of implementation. Notes from that meeting are available.

Hangman Creek also has dissolved oxygen and pH impairments which are typically the result of excess nutrients like nitrogen and phosphorus. Ecology collected water quality data on dissolved oxygen, pH, and nutrients in the watershed. This data will be used to develop a separate TMDL to address these parameters when resources become available. However, much of the implementation needed to address the original TMDL will also address nonpoint sources contributing to the dissolved oxygen and pH impairments. The nutrient water quality data will also be useful as we measure the progress toward meeting the phosphorus allocation set at the mouth by the Spokane River Dissolved Oxygen TMDL.

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Last updated April 2016
  Water resource inventory area (WRIA) 56 map, Washington State.


WRIA(s): #56 (Hangman)

Water-body Names:
California Creek
Hangman Creek
Little Hangman Creek
Marshall Creek
Rock Creek
Rattler Run Creek
Spangle Creek

Fecal Coliform

# of TMDLs: 27

Implementation plan sent to EPA

Contact Info:
Elaine Snouwaert
Phone: 509-329-3503
Email: Elaine.Snouwaert@ecy.wa.gov

Eastern Region
Department of Ecology
4601 N Monroe Street
Spokane, WA 99205-1295