Water Quality Improvement Projects
North Creek Watershed

North Creek watershed, Washington State.  Photographer unknown.

North Creek is polluted with fecal coliform bacteria and needs your help. Fecal coliform bacteria, found in the waste of warm-blooded animals, is a major concern in the creek because it indicates that people may be exposed to a variety of harmful bacteria and viruses. Ecology developed the North Creek Fecal Coliform Total Maximum Daily Load Detailed Implementation Plan (Action Plan) to help explain the bacteria pollution problem and point out solutions to get these waters clean again.


The North Creek watershed drains approximately 30 square miles and discharges to the Sammamish River. The seven smaller watersheds that make up the North Creek watershed include the Silver Lake; Penny; Nickel; Silver; Tambark; Sulphur Springs; and Mainstem subbasins (see subbasins map).

North Creek is classified as an extraordinary primary contact waterbody in Washington’s Water Quality Standards. Streams like North Creek should be suitable for a wide variety of uses including water supply; stock watering; fish migration, rearing, spawning, harvest; wildlife habitat; and recreation (swimming, fishing, and aesthetic enjoyment).

Cleaning up North Creek will be a challenge, but it can be done.

Water quality issues

Pollution in the North Creek watershed comes from thousands of sources that may not have clearly-identifiable emission points. This category of pollution is called non-point pollution. These non-point sources can contribute a variety of pollutants that may come from failing septic systems; livestock and pet wastes; at-home car washing; lawn and garden care; leaky machinery; and other daily activities. Some of these non-point sources create fecal coliform bacterial pollution that indicate the presence of fecal wastes from warm-blooded animals and humans. Ecology has confirmed that high levels of fecal coliform bacteria exist in North Creek.

Although wildlife contribute to bacteria pollution in North Creek, the majority of the problem occurs because of human activities. The way we do things, not the activities themselves, are typically the problem. For example, having dogs, cats, horses, and other animals as part of our life is not a problem; rather, it is the way that we care for these animals. Similarly, roads and parking lots are a necessity in modern society, but the way we build roads, neighborhoods, and shopping centers causes our local streams and creeks to be polluted. There are solutions that can be undertaken by local governments, businesses, organizations, and citizens to solve the problem. These solutions are discussed in the Action Plan.

North Creek, Washington State.  Photographer unknown.

Status of the project

In June 2001, Ecology prepared its initial report, a total maximum daily load (TMDL) on North Creek’s high fecal coliform levels. In 2002 we submitted it to EPA for approval. During 2003 we worked with local governments to discuss solutions and published a detailed implementation plan (Action Plan).

All of the local governments in the watershed have been working to resolve the bacterial pollution problems in North Creek as part of their NPDES Municipal Stormwater Programs. They are mapping and cleaning their stormwater systems, installing pet waste stations, educating the public, monitoring bacteria levels in local streams, and looking for sources of bacteria as part of their illicit discharge detection efforts. You can learn more about the programs at each city, and in unincorporated Snohomish County, by visiting their websites and reading their Bacteria Pollution Control Plans and Stormwater Management Plans.

Why this matters

Fecal coliform is a type of “bacteria” common in human and animal waste. It indicates that sewage or manure is entering a water body. As the level of fecal coliform increases, the risk of people getting sick from playing or working in the water increases. 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.

Although North Creek is a relatively small urban stream, there are many places in the watershed where children can play and be exposed to polluted water. In addition, North Creek ultimately flows into Lake Washington, which is an important recreational area during summer months.

People can help keep bacteria out of the water. Properly collect, bag, and trash dog poop. Check your on-site sewage system to make sure it is maintained and working properly. Ensure livestock and manure are kept away from the water. Report problems to your local government if you see a likely pollution source that can be fixed.

Technical information

North Creek Watershed: Total Maximum Daily Load Evaluation for Fecal Coliform Bacteria (Ecology publication)

North Creek Fecal Coliform Total Maximum Daily Load Submittal Report (Ecology publication)

North Creek Fecal Coliform Bacteria Total Maximum Daily Load: Detailed Implementation Plan (WQIP) (Ecology publication)

North Creek, Washington State.  Photographer unknown.

Related information


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Last updated June 2016
  Water resource inventory area (WRIA) 8 map, Washington State.


WRIA: #8 (Cedar/Sammamish)

Water-body Name:
North Creek watershed

Fecal coliform bacteria

# of TMDLs: 3

Fecal Coliform TMDL - approved
Has implementation plan

Contact Info:
Ralph Svrjcek
Phone: 425-649-7165
Email: Ralph.Svrjcek@ecy.wa.gov

Northwest Region
Department of Ecology
3190 - 160th Ave. SE
Bellevue, WA 98008-5452