Water Quality Improvement Project
South Fork Palouse River:
The South Fork Palouse River drains 130 square miles around the towns of
Pullman and Albion in Washington and Moscow, Idaho. Grain fields and
pastures dominate the area. The major land use is farming with
residential, commercial, and industrial developments clustered around
Water quality issues
The South Fork Palouse River and several other tributaries are impaired for
one or more of the following pollutants: ammonia; dissolved
oxygen; fecal coliform bacteria; PCBs; chlorinated pesticides;
temperature; and pH.
Status of the projects
The following is the timeline for the South Fork Palouse River
watershed water quality improvement project.
Dissolved oxygen / pH / Temperature
Dissolved oxygen, pH, and temperature affect
the health and distribution of fish and other aquatic life. The South Fork Palouse River is impaired by high
temperatures, low dissolved oxygen, and pH outside the range
appropriate for fish and other aquatic life. Excessive nutrients in
the stream (for example nitrogen, including ammonia, and phosphorus) can affect the level of dissolved oxygen and pH in the
- From May 2006-October 2006 Ecology conducted a temperature
study. It ran during the time of year when the water is most likely
to be impaired. Another study examined dissolved oxygen, pH,
and nutrients. Data for the dissolved oxygen and pH study were collected in conjunction with the bacteria study and
intensive surveys that were conducted in June and August 2006.
- In late 2009, Ecology applied for EPA funding to hire a contractor to
study the aquatic life (fish and insects) in the streams. In May
2010 a contract
was awarded to Tetra Tech, Inc. to research historical
literature about aquatic life in the watershed and collect fish and
insects during the summer/fall of 2010. This information will assist
Ecology in determining the appropriate water-quality standard
criteria to protect the
stream for the aquatic species that should be present in the
watershed under natural conditions (unaltered by human activities).
final report was completed in spring 2011.
In June and August 2010, Ecology conducted additional intensive
surveys of dissolved oxygen, pH, and nutrients. The purpose of these
studies was to determine the effect of changes at the Moscow
wastewater treatment plant, located just across the state line on Paradise
Creek, on water quality downstream in Washington. The Moscow
treatment plant installed filtration to significantly reduce the
amount of nutrients discharged to Paradise Creek. This additional
information will be useful to further calibrate the computer
model Ecology is using to analyze the watershed.
Fecal coliform bacteria come from the intestinal tract of
warm-blooded animals and can indicate the presence of human and animal
waste which may carry disease-causing organisms.
- From May 2006-May 2007, Ecology conducted a study that examined
the levels and distribution of fecal coliform bacteria throughout
the watershed. The study found that the South Fork Palouse River;
Paradise Creek; Airport Road Creek; Missouri Flat Creek; Dry Fork
Creek; Spring Flat Creek; Staley Creek; and Four Mile Creek violate
the fecal coliform bacteria water quality standards during a portion
of the year.
In June 2008, Ecology formed an advisory group to review the studies'
results and recommend strategies to improve water quality. More
information about the activities of the advisory group are available on
the SFPR TMDL Advisory Group page.
- In August 2009, Ecology completed the water quality improvement report on
fecal coliform bacteria. After the public
comment period, Ecology
addressed the comments received. On October 22, 2009 Ecology submitted the final
improvement report to EPA. EPA approved the submittal in January 2010.
- Ecology, with the assistance of several entities and the SFPR
TMDL Advisory Group, developed an implementation plan describing how
the water quality goals in the water quality improvement report will
be implemented. The draft plan was available for public review until November 18, 2011.
After Ecology reviewed and responded to comments received, we sent a copy of
the finalized plan to EPA for their records.
During the Palouse River toxics study, the South Fork Palouse River was found
to be impaired for PCBs and dieldrin (a chlorinated pesticide). These impairments are addressed through the Toxics TMDL,
which EPA approved in November 2007.
A TMDL for ammonia in the
South Fork Palouse River, including Paradise Creek, was completed in 1993. After
this TMDL was approved, the water quality criteria for ammonia was changed. An
addendum to the
original TMDL to reflect the revised criteria was published in 1995.
To learn more about the importance of these various parameters, please see our water quality
Unless otherwise specified, the following documents are Ecology publications.
Streamflow Summary for the Palouse and South Fork Palouse Rivers and Selected Tributaries, 2006-08
Dissolved oxygen / pH / Temperature
Quality Assurance Project Plan: South Fork Palouse River Dissolved Oxygen and pH Total Maximum Daily Load Study
South Fork Palouse River Temperature TMDL Study Quality Assurance
Instream Assessment of Biota and Migration Patterns of the South Fork Palouse River Watershed
Quality Assurance Project Plan for In-Stream Assessment of Biota and Migration Patterns of the South Fork Palouse River Watershed
Fecal coliform bacteria
South Fork Palouse River Watershed Fecal Coliform Bacteria Total Maximum
Daily Load: Water Quality Implementation Plan
South Fork Palouse River Fecal Coliform Bacteria TMDL: Water
Quality Improvement Report
Quality Assurance Project Plan: South Fork Palouse River Fecal Coliform
Bacteria Total Maximum Daily Load Study
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WRIA: #34 (Palouse)
South Fork Palouse River
Airport Road Creek
Missouri Flat Creek
Dry Fork Creek
Spring Flat Creek
Four Mile Creek
Fecal coliform bacteria
PCBs and dieldrin
# of TMDLs:
Ammonia-N - 1
Fecal coliform bacteria - 4
Ammonia-N - Approved by EPA.
Fecal coliform bacteria - Approved by EPA.
Has implementation plan.
Dissolved oxygen/pH/Temperature - under development.
Department of Ecology
4601 N Monroe Street
Spokane, WA 99205-1295