The Stillaguamish River and many of its tributary streams exceed Washington State water quality recreational contact standards for fecal coliform bacteria. That means it can be unsafe for you, your family members, and your pets to come in contact with these waters. Fecal coliform is a widely used indicator of the presence of other organisms that can cause illnesses such as typhoid, cholera, dysentery and hepatitis A. Fecal coliform is bacteria found in the feces of warm blooded animals including humans and other mammals. Sources of fecal bacterial pollution in the CWD include human sewage, livestock, pets, and wildlife.
In 2007, Snohomish County published the State of the Stilly Report summarizing conditions and trends associated with County sampling locations in the Stillaguamish Watershed. This report found that while high fecal coliform levels were present, there was an improving trend for some stream and river segments partially due to wastewater treatment plant upgrades, dairy waste management, and septic system maintenance. While these sites demonstrated improvement or no change in a parameter, the report found that many still did not meet water quality standards.
In 2011, Snohomish County began using the Stillaguamish Microbial Water Quality Assessment (MQWA) methodology to identify sources of point and non-point pollution that require corrective action. Existing water quality data for the ten year period of 2001-2011 were analyzed in order to assign each creek or river basin a “rank” corresponding to the level of bacterial pollution. The Portage Creek, Church Creek, and Lower Stillaguamish sub-basins exhibited the highest fecal coliform levels and were selected as priority areas to apply a focused pro-active approach to identify and correct potential bacteria pollution sources. View the map at right for the locations of water quality sampling sites and their respective “ranks.”
Water Quality Standards
The federal Clean Water Act requires all states restore waterways to be “fishable and swimmable.” Water quality standards, defined by Ecology, are the basis to restore, protect and regulate the quality of surface waters for aquatic life, public health and the use and enjoyment of our waters. Each water quality parameter, such as fecal coliform and dissolved oxygen, has criteria set forth for fresh water and marine water.
Ecology compiles water quality sampling results and assesses fresh and marine waters for compliance with water quality standards. Those that do not meet standards are placed on the 303(d) list. A description of the process and tools to locate waters exceeding fecal coliform standards can be found here.
Water quality clean-up plans or Total Maximum Daily Load (TMDL) plans are developed and implemented for waters placed on the 303(d) list. The Stillaguamish River Multi-Parameter TMDL describes the problems and actions stakeholders, including the public, can take to improve water quality.