Because pollutants can adversely affect the organisms living in the sediment, our team of Ecology scientists has monitored Puget Sound sediment quality for over two decades. We measure levels of chemicals and toxicity, and identify and count invertebrates living in sediment samples to determine the overall condition of the bottom of Puget Sound.

Puget Sound Marine Sediment Indicators

We use Puget Sound Sediment Quality Indicators to communicate the current condition and changes in sediment quality to the interested public, decision makers, scientists and others. These indicators are a useful tool for the development of strategies to protect Puget Sound for this and future generations.

Marine Sediment Monitoring Programs

We examine Puget Sound sediments on different geographic and time scales. Click on the tabs and maps below to explore sediment quality in regions, urban bays, and at long-term monitoring stations to look for changes over time. Included are descriptions of our sediment monitoring programs, a summary of findings, and links to reports and data.

Regional Sediment Monitoring

The Regional Program assesses sediment over time in eight geographical areas.  To explore the sediment quality of these geographic regions, click on the region in the map below.

Sample Design and Methods

Urban Bays

Ecology's Urban Bay Program assesses sediment quality over time in six urban bays.  To explore the sediment quality of these urban bays, click on the bay name in the map below.

Long Term Sediment Monitoring

The Long-Term Program has monitored 10 Puget Sound stations annually since 1989. Stations were chosen for their unique assemblages of benthic invertebrates and for their relationship with Puget Sound fish and water quality monitoring programs.

Sample Design and Methods

Location of 10 long-term sediment monitoring stations in Puget Sound.

Data Summaries, Findings, Publications


EPA Joint Monitoring

Ecology partnered with EPA and other natural resource agencies from California, Oregon, Alaska, and Hawaii to conduct the National Coastal Condition Assessment Program, formerly known as Western Coastal Environmental Monitoring and Assessment Program (EMAP). This efforts answers broad scale questions on environmental conditions of the United States coast. Program goals, study design, and methods are summarized here.

Ecological health indicators monitored included:
  • water quality
  • habitat condition
  • sediment quality
  • benthic community condition
  • fish-tissue contaminants
Sampling in Washington State included:
  • 1999 – Grays Harbor, Willapa Bay, and other coastal estuaries, Lower Columbia River
  • 2000 – Puget Sound
  • 2002 – Puget Sound and coastal estuary intertidal zones
  • 2003 – Pacific Ocean Coast - offshore
  • 2004 – Puget Sound and coastal estuaries
  • 2010 – Puget Sound and coastal estuaries


1999 WA Statistical Summary
2000-2003 WA Statistical Summary


National Coastal Condition Reports
Marine Sediment Monitoring photo banner

Sediment Quality in Elliot Bay, Seattle, WA, 2013


Sediment Quality in Commencement Bay, Tacoma, WA, 2014