Swan Creek Action Plan and Implementation

About the Project

 Since 2008, the Pierce County Surface Water Management (SWM) Division has tracked and reported the water quality of streams and lakes in an annual summary.  By observing the chemical and physical properties of the stream, we can better understand stream health and the impacts it may have on humans, fish and wildlife.

The water quality in lower Swan Creek near Pioneer Way is typically relatively good. However, the water quality sampling locations at 84th Street and 96th Street tend to score lower, usually labeled as moderate or poor. This consistently low score is due to high levels of fecal coliform, nitrogen and phosphorus, all of which can come from human and animal waste. In addition, Swan Creek is on the Washington State 303(d) list of polluted waters for fecal coliform. 

Macroinvertebrates (bugs living at the bottom of streams) are useful indicators of stream quality because they generally spend their life cycles in a small area, have a short life span and are sensitive to subtle changes in water quality or habitat. Different macroinvertebrate species have various levels of tolerance to pollution. Some species that are important food sources for salmon, such as mayflies, stoneflies, and caddis flies, are very intolerant to pollution. 

In an unhealthy stream the amount of these species will decline while the numbers of more pollution-tolerant species like leeches and black fly larvae, which salmon do not eat, will increase. In the case of Swan Creek, the degraded habitat appears to be limited in its diversity of environments, which in turn limits the diversity of the bugs.

In 2012, a project team made up of SWM staff was assigned to identify problems, partners, and solutions to improve water quality in Swan Creek. 

Pierce County contracted with GeoEngineers to research information about the Swan Creek basin, collect additional data and create an action plan. The final product is the Swan Creek Watershed Characterization and Action Plan. Completed in 2015, it includes strategies to improve water quality and reduce sediment in the creek.