Geographic boundaries of Puget Sound and the Salish Sea

The boundaries of Puget Sound and the Salish Sea are not always consistently defined by scientists and government agencies. This article clarifies the distinctions between oceanographic and watershed-based definitions of these geographic areas. 

Water Resource Inventory Areas (WRIA). Map: Kris Symer. Data source: WAECY.
Water Resource Inventory Areas (WRIA). The Washington State Legislature defines Puget Sound as WRIA 1-19. These areas were first developed in 1970 and updated most recently in 2000. Map: Kris Symer. Data source: WAECY.

Puget Sound

There are several ways that scientists and managers have defined the boundaries of Puget Sound. To oceanographers, Puget Sound includes the waters from Admiralty Inlet and Deception Pass to the southern tip of Olympia (Ebbesmeyer et al., 1988).

However, many management and conservation efforts incorporate the entire watershed—the land where rivers and streams drain into Puget Sound—as well as the Strait of Juan de Fuca, Hood Canal and the San Juan Archipelago. Accordingly, "Puget Sound" is defined by the Washington State Legislature as:

“Puget Sound and related inland marine waters, including all salt waters of the state of Washington inside the international boundary line between Washington and British Columbia, and lying east of the junction of the Pacific Ocean and the Strait of Juan de Fuca, and the rivers and streams draining to Puget Sound as mapped by water resource inventory areas 1 through 19 in WAC 173-500-040 as it exists on July 1, 2007” (RCW 90.71.010: Definitions, n.d.). 

Puget Sound basins. Map: Kris Symer. Data source: WDFW.
Puget Sound basins. The oceanographer’s definition of Puget Sound is limited to the following marine basins: Hood Canal, Main Basin (Admiralty Inlet and the Central Basin), South Basin, and Whidbey Basin. Map: Kris Symer. Data source: WDFW.

Salish Sea

The Salish Sea extends across the U.S.-Canada border, and includes the combined waters of the Strait of Georgia, the Strait of Juan de Fuca, Puget Sound and the San Juan Islands. The name Salish Sea was proposed in 1989 to reflect the entire cross-border ecosystem. Both Washington State and British Columbia voted to officially recognize the name in late 2009. The name honors the Coast Salish people, who were the first to live in the region (Salish Sea: Naming, n.d.). 

More information on the ecology and naming of the Salish Sea is available from the SeaDoc Society and Western Washington University.

Map of Salish Sea basin and water boundaries w/ WRIA boundary for reference. Map: Kris Symer. Data: Stefan Freelan; WAECY.
Salish Sea basin and water boundaries. The Salish Sea water boundary (blue) includes the Strait of Georgia, Desolation Sound, The Strait of Juan de Fuca, and Puget Sound.  The larger watershed basin (green) is the area that drains into Salish Sea waters. WA Water Resource Inventory areas (WRIA) boundary lines are shown for reference. Map: Kris Symer. Data: Stefan Freelan; WAECY.

 

Interactive map: Explore Salish Sea and Puget Sound basins

 

References

 

Ebbesmeyer, C. C., J. Q. Word, and C. A. Barnes (1988): Puget Sound: a fjord system homogenized with water recycled over sills by tidal mixing. Hydrodynamics of Estuaries: II Estuarine Case Studies, B. Kjerfve, Ed., CRC Press, 17-30.

Freelan, S. (2009). Salish Sea basin and water boundaries. Retrieved October 1, 2015, from https://erma.noaa.gov/northwest/erma.html#/x=- 123.30659&y=49.05603&z=7&layers=3+7654+7499

Washington Department of Fish and Wildlife. Puget Sound Basins (WDFW). ERMA northwest. Retrieved September 30, 2015, from https://erma.noaa.gov/northwest/erma.html#/x=- 123.44039&y=48.39419&z=8&layers=16+7531

RCW 90.71.010: Definitions. (n.d.). Retrieved August 31, 2015, from http://apps.leg.wa.gov/rcw/default.aspx?cite=90.71.010

Salish Sea: Naming. (n.d.). Retrieved August 31, 2015, from http://www.wwu.edu/salishsea/history.shtml

Washington State Department of Ecology. WAECY - Water Resource Inventory Areas (WRIA). Washington State Open Data Bridge. Filter: Puget Sound WRIA 1-19. Retrieved September 29, 2015, from http://geo.wa.gov/datasets/d3071915e69e45a3be63965f2305eeaa_0?orderByFields=W RIA_NR+ASC&where=WRIA_NR+%3E%3D+1+AND+WRIA_NR+%3C%3D+19&filter ByExtent=true&geometry=-125.749%2C44.343%2C-118.96%2C48.712&mapSize=mapmaximize