Since 2008, the Surface Water Management (SWM) division has tracked and reported the water quality of streams and lakes in an annual Surface Water Report Card. Streams and lakes are graded on a scale of 'F' (failing) to 'A' (excellent). In 2012, a project team was assigned to identify problems, partners, and solutions to water quality in Swan Creek.
In 2014, Swan Creek received a "C-" grade. The consistently low grade 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. The Benthic Index of Biotic Integrity (BIBI) score for Swan Creek is also poor. This is also included in the calculation of the grade. The BIBI score is based on the type and amount of bugs that live on the bottom of the stream. The type and amount of bugs can tell a lot about the health of a stream. 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".
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 and it includes strategies to improve water quality and reduce sediment in the creek and reprioritization of stormwater facilities and needed actions, upgrades and repairs.