Where is the Salish Sea?
Geography of the Salish Sea Bioregion. Part of the Salish Sea Atlas.
Welcome to the Salish Sea Bioregion!
The Salish Sea is an intricate network of inland marine waterways in Washington and British Columbia. The exceptionally biologically rich waters of this transboundary estuarine ecosystem are home to many charismatic and threatened species. The Salish Sea Bioregion includes both the marine waters and their upland watersheds. Over nine million people live in this bioregion, which encompasses the Vancouver-Seattle megaregion.
Although divided by an international border, the Salish Sea Bioregion can in many ways be considered a cohesive geographic unit based on its natural and cultural characteristics and history. The concept of a cohesive Salish Sea region has become a critical focal point for local education, research, restoration, conservation, and policy development.
You can navigate around this interactive map to explore the place names, topography, and bathymetry of the Salish Sea Bioregion
Facts about the Salish Sea Bioregion:
- Area of the bioregion: 102,727 square kilometers (39,663 square miles)
- Surface area of marine waters: 17,803 square kilometers (6,874 square miles)
- Area of land and freshwater: 84,924 square kilometers (32,789 square miles)
- Percent of the bioregion covered by marine waters: 17
- Coastline length (including all islands and inlets): 9,427 km (5,858 miles)
- Islands: 535 individually named islands, 90 named island groups
Coast Salish
The Salish Sea is named after the Coast Salish peoples who have been the stewards of these lands and waters for millennia. The map below shows the approximate distribution of Coast Salish languages spoken in the early 19th century.
You can zoom, pan, and click around this interactive map to compare place names with the approximate distributions of the Coast Salish languages.
Many of these fourteen languages have multiple dialects and are or were spoken by numerous distinct communities. These linguistic regions do not represent territories, land claims, or other political boundaries. The borders of these regions overlap in many places and have of course changed over time.
Please treat this map as a very approximate, only partially accurate, and deeply humble attempt to represent the astounding linguistic diversity of the Coast Salish peoples.
Today many of us think of the Salish Sea region as being divided by the US-Canadian international border. This map reminds us that the international border is a very recent invention that does not reflect the long history of interconnected human societies living in this region. We may also think of the mainland and islands as being separated from each other by the marine waters of the Salish Sea. This map reminds us that the sea itself has traditionally acted as a transportation corridor connecting communities rather than a barrier.
Marine Waters and Islands
Major marine bodies of water in and around the Salish Sea
The Salish Sea encompasses three main bodies of water: the Strait of Georgia in the north, Puget Sound in the south, and the Strait of Juan de Fuca in the west. The Salish Sea also contains or connects to numerous bays, coves, inlets, and channels. Hundreds of named and unnamed islands can be found in the Salish Sea, including the Gulf Islands and San Juan Islands archipelagos.
The name of the Salish Sea was formally recognized and defined by the United States in 2009 and by Canada in 2010 . The US and Canadian definitions of the northern boundary are slightly different, so this atlas uses a generous interpretation including all the channels and inlets south of Johnstone Strait and Bute Inlet that connect to the Strait of Georgia.
Why is Johnstone Strait and its associated inlets not included in the Salish Sea? The legal definitions used in the US and Canada both exclude these northern waters because there is relatively little exchange of water in or out of the Salish Sea along its northern border. Results of oceanographic circulation models show that the vast majority (approximately 95%) of water exchange between the Salish Sea and the Pacific Ocean occurs through the Strait of Juan de Fuca, with the small remainder passing through the northern channels and Johnstone Strait. There are also no streams north of the border used in this atlas that feed directly into the Salish Sea. The northern border we use here therefore represents a natural divide based on both marine water exchanges and freshwater inputs.
You can use this interactive map to find the names of islands and marine water bodies in the Salish Sea Bioregion. Zoom, pan, and click on features to learn their names.
Use the buttons below to quickly navigate to these locations:
Bioregion and Watersheds
A bioregion is a territory defined not by political borders, but by the natural geographic boundaries of ecosystems and human communities. This is a particularly relevant concept for ecosystems that cross international borders. Management, conservation, research, and education related to transboundary ecosystems requires that processes on both sides of the border are taken into account. Physical, ecological, and even many cultural systems do not stop at international borders. A bioregional perspective is thus often necessary to understand transboundary ecosystems such as the Salish Sea.
The Salish Sea Bioregion includes the marine waters of the Salish Sea proper as well its watersheds. These upland areas are intimately connected to the marine waters through hydrological and cultural connections.
For this atlas, the bioregional boundary exactly follows the borders of HUC-8 level US watersheds and sub-sub-drainage basin level Canadian watersheds that directly or indirectly drain into the Salish Sea throughout most of the region. The watersheds at the northeastern and northwestern corners of the boundary were clipped along sub-basin boundaries to remove portions of the larger watersheds that drain into Johnstone Strait or Bute Inlet rather than the Salish Sea. Watersheds in the Fraser River’s upper drainage area were also excluded to keep the bioregion constrained to an area of more similar climatic and ecological characteristics.
This map shows the boundaries of the watersheds in the Salish Sea Bioregion in green, along with outlines of the coastal and Fraser River drainage basins that connect to the Salish Sea Bioregion but were excluded for the purposes of this atlas.
Zoom and pan to explore this map. Click on any watershed to learn its name and size. Which watershed do you live in?
Data and Sources
Visit the Salish Sea Atlas website to access all of the atlas's data, chapters, and reference maps.
View data sources and processing details, or download the datasets used in this chapter of the Salish Sea Atlas :
