Salish Sea

Executive Summary

Map of Salish Sea watershed
What is the Salish Sea? The Salish Sea is a marine ecosystem that extends from the north end of the Strait of Georgia in British Columbia, Canada, to the south end of Puget Sound in Washington in the U.S., and west to the mouth of the Strait of Juan de Fuca where it meets the Pacific Ocean. Map courtesy of Western Washington University.
Diagram showing interconnection between the ten ecosystem indictors being studied in EPA and Environment Canada's Health of the Salish Sea Ecosystem Report.
We're studying the trends for ten interconnected environmental indicators that help give us a better picture of the current environmental, economic, and social well-being of our Salish Sea watershed.

Coast Salish people have lived in balance within the Salish Sea ecosystem since time immemorial. Currently, over seven million people live in the areas around the Salish Sea, benefitting from the resources the ecosystem provides. By the year 2025, we can expect the population in the Salish Sea ecosystem to expand to over nine million people. Sustainability of the Salish Sea ecosystem is critical to our continued use and enjoyment of this place.

The Health of the Salish Sea Report - a joint initiative between EPA and Environment Canada - describes trends that help us identify priorities for future action across the entire Salish Sea. In 2000, EPA and Environment Canada signed a Joint Statement of Cooperation to facilitate cross-border understanding, dialogue, and collaboration on Salish Sea issues. From this partnership came the Salish Sea indicators to help show where we are seeing progress in sustainably managing the Salish Sea ecosystem and its valuable resources, where conditions are declining, and where course corrections are needed.

To help convey the status and trends of ecosystem components and how they relate to human activities, ten indicators address the following questions:

  1. What's happening?
  2. Why is it important?
  3. Why is it happening?
  4. What are we doing about it?

For each indicator, we also present Coast Salish Traditional Ecological Knowledge as "sustainable perspectives." Coast Salish knowledge allows us to extend the timeline for indicators and draws attention to the significance of connections among indicators.

Ecosystem Trends

We see positive trends on some issues, such as improving air quality and reductions in certain persistent toxic chemicals in the aquatic food web. Other issues, such as habitat protection and water quality, need more attention.

Below are summaries of the ten indicators we're studying. To learn more about the status of each indicator, follow the links provided to our full reports.

State of Air


Air Quality (Fine Particulates) - Improving

Green indicator icon

13 of the 14 air monitoring stations in our study meet both Canadian and U.S. standards, and air quality is generally improving thanks to new actions in Washington and British Columbia that control sources of air pollution.

State of Species


Photo of killer whales
Killer Whales and Salish people have lived together in this place for at least 5000 years. In the late 1800's, the orca population was estimated at over 200. Today their numbers are less than half that. Photo courtesy of Stewart Yee.

Marine Species at Risk - Declining

Red indicator icon

Between 2008 and 2011, 23 new species were identified as threatened or of concern, representing the greatest increase since reporting was established in 2002.

Chinook Salmon - Declining

Red indicator icon

Chinook salmon populations are down 60% since the Pacific Salmon Commission began tracking salmon data in 1984.

Southern Resident Killer Whales (Orcas) - Neutral

Yellow indicator light

Although there was a steep decline between 1994 and 2001, the population appears to have stabilized in recent years.

Toxics in the Food Web: Pacific Herring and Harbor Seals - Improving

Green indicator icon

Levels of PCBs in harbor seals have been declining since the 1980s, though the decline has slowed in recent years. Levels of flame retardant chemicals - called PBDEs - are also declining in harbor seals.

State of Water


This sand-rose anemone, like many aquatic creatures with low mobility, cannot easily escape the effects of low oxygen levels. Photo courtesy of Chad King/NOAA.

Freshwater Quality - Improving

Green indicator icon

Of the seventeen rivers we assessed, none showed statistically significant declining trends over the ten year period from 2000 to 2010. Though twelve of the rivers either regularly or occasionally exceeded water quality guidelines, improving trends were observed in three of the rivers (Samish, Nisqually, and Deschutes).

Marine Water Quality - Declining

Red indicator icon

Marine dissolved oxygen is showing a long term decline in the waters of Puget Sound and in the deeper waters of Georgia Strait. Marine Water Condition Index scores also have been in general decline over the past ten years for many areas in Puget Sound.

Stream Flow - Declining

Red indicator icon

10 of the 17 rivers we studied showed decreasing summer flow trends since 1975. Five of the remaining seven rivers showed only minor increases or decreases in flow. Streamflow is vital to how humans and aquatic organisms use Salish Sea waterways. Humans put demands on waterways that can severely degrade and disrupt natural processes, such as salmon migrations.

State of Human Well-Being


When water quality is poor, shellfish areas may be closed to harvesting if there's a potential health risk from eating the shellfish.

Shellfish Beaches - Neutral

Yellow indicator light

Since our last report in 2005, over 3,800 acres of previously closed shellfish beds in Puget Sound have been upgraded or re-opened due to improvements in water quality. However, there's been an overall increase in the number of acres of shellfish beds that are prohibited or restricted from harvesting. This increasing trend may be due partly to increased water quality monitoring.

Swimming Beaches - Neutral

Yellow indicator light

Overall, nearly three-quarters of swimming beaches in the Salish Sea consistently meet standards. This indicator is also closely linked to local actions.

Inspire Action

We all have a common interest and a responsibility to protect and restore the Salish Sea. Government action alone cannot address these issues. Community groups, non-profits, tribal governments, cities and municipalities are delivering protection and restoration work that's showing some results. Important examples of this work be found at:

More action is needed. You can use the ecosystem indicators presented in this report to encourage conversation, identify partners in collaboration, and inspire action to improve ecosystem health. The information and links identifying other sources of information can help all of us identify specific areas and actions that need our attention and efforts.

About the Data

This report updates previous Puget Sound-Georgia Basin ecosystem indicator reports (in 2002 and 2006) and expands the suite of information to increase their relevance to ecosystem health, including human well-being.

A number of current publications report on environmental conditions in the Salish Sea. This report draws on existing publicly-available information, including agency technical reports, scientific sampling from Canadian and U.S. sources, and scientific work by non-governmental organizations. This integration involves significant collaboration among multiple agencies and stakeholders.