Report: Sediment quality in Central Puget Sound

Benthic invertebrates are indicators of sediment health. Photo by D. Hyrenbach, NOAA.
Benthic invertebrates are indicators of sediment health. Photo by D. Hyrenbach, NOAA.

Sediment health in Central Puget Sound has shown a recent steep decline, according to a report by the Washington Department of Ecology. The report compares monitoring data over a ten-year period between 1998/1999 and 2008/2009.

Researchers monitored populations of benthic invertebrates, sediment-dwelling organisms that depend on an environment free of pollutants, as part of the Puget Sound Ecosystem Monitoring Project (PSEMP). The report shows that adversely affected invertebrates were found across 28% of the region, compared with 7% ten years prior.

Sediment samples were also tested for 133 different potentially toxic chemicals. Samples revealed an overall increase in low-level toxicity in sediments, but decreasing concentrations of lead, mercury, silver, and tin. Ecology will continue testing and monitoring sites throughout the Sound.

Read more about the report on the Department of Ecology website.

Download a pdf of the report, Sediment Quality in Central Puget Sound, Changes Over a Ten-Year Period.