Water Quality Improvement Project
Palouse River Area:
Fecal Coliform Bacteria


As part of a larger effort to address all water quality impairments in the Palouse River watershed, Ecology began a project on fecal coliform bacteria on the mainstem Palouse River in 2007. This project addresses the Palouse River from Colfax to the Palouse Falls and Rebel Flat Creek. The mouths of major tributaries are also included.

Previous efforts to address bacteria in the watershed include water quality improvement projects on the North Fork Palouse River and the South Fork Palouse River. (See Study Area map)

Why this matters

Fecal coliform is a family of bacteria common in human and animal waste. These bacteria include many species of bacteria, including Escherichia coli (E. coli). High levels of these bacteria can indicate untreated sewage or manure is entering streams, making them unsafe for recreation. Bacteria can get into our waters from untreated or partially treated discharges from wastewater treatment plants, from improperly functioning septic systems, and from livestock, pets and wildlife.

To learn more about the importance of this parameter, please see our water quality impairments page.

Status of the project

Ecology collected bacteria samples and stream flow from 28 sites twice per month from June 2007 to May 2008 (see map). After analyzing the data, we found that most of the Palouse River sites met the bacteria water quality standard but that major reductions were needed in several of the tributaries.

Ecology worked with several organizations in the watershed to draft an implementation plan describing methods to address multiple pollution sources such as degraded riparian areas, failing septic systems, livestock, and stormwater.

The study and the implementation plan have been published in the draft Palouse River Fecal Coliform Bacteria Total Maximum Daily Load: Water Quality Improvement Report and Implementation Plan.

This plan was available for public review and comment from October 18 through November 17, 2010. Comments were reviewed and responded to in an appendix to the report. After any other necessary revisions to the report were made, it was submitted to the Environmental Protection Agency (EPA) for approval. EPA approved the TMDL on March 8, 2011.

Technical information

Streamflow Summary for the Palouse and South Fork Palouse Rivers and Selected Tributaries, 2006-08

Palouse River Fecal Coliform Bacteria TMDL: Water Quality Improvement Report and Implementation Plan (Ecology publication)

Quality Assurance Project Plan: Palouse River Bacteria Total Maximum Daily Load Water Quality Study Design (Ecology publication)
This quality assurance project plan (QAPP) describes the technical study that will monitor levels of fecal coliform bacteria in the Palouse River watershed and will form the basis for a bacteria TMDL. The study will be conducted by Ecology’s Environmental Assessment Program.

Related information

WRIA 34: Palouse Watershed Information (Environmental Assessment Program web site)


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Last updated March 2011


WRIA: #34 (Palouse)
County: Whitman

Water-body Names:
Palouse River
Rebel Flat Creek
Willow Creek

Fecal coliform bacteria

# of TMDLs: 3

Approved by EPA
Has implementation plan

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