Restoring salmon access and nutrient-rich habitat at the mouth of the Squamish River in British Columbia

Estuaries provide young salmon with a safe and nutrient-rich environment where they can grow and adapt to saltwater before entering the ocean. These areas where the river meets the ocean offer out-migrating juvenile salmon with abundant food, shelter from predators and a gradual transition from freshwater to saltwater, all of which increase their chances of survival during this critical life stage. The Skwelwil’em Estuary at the mouth of the Squamish River has immense ecological and cultural value to Sḵwx̱wú7mesh Úxwumixw (Squamish Nation).

Historically, the Squamish River flowed across the estuary floodplain together with the Mamquam River and was home to Sḵwx̱wú7mesh Úxwumixw villages. Recent urban development has significantly altered the lower floodplain negatively impacting the sensitive ecosystem. In particular, the habitat of the Skwelwil’em Estuary was cut off from the river by a five-kilometre berm supporting a road, originally built in 1970, in anticipation of a coal port. The coal port was never constructed, but the berm remained which became a barrier for fish passage, especially for the young juvenile Chinook salmon making their way out to the ocean.

Now, through the Pacific Salmon Strategy Initiative (PSSI) we have embarked on a collaborative restoration effort with Sḵwx̱wú7mesh Úxwumixw (Squamish Nation), the Squamish River Watershed Society (SRWS) and the Province of British Columbia to restore the estuary’s natural function and biodiversity.

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Improving estuary access for juvenile salmon

In the latest phase of this estuary restoration project, we have worked with partners to replace the undersized steel pipe culverts from 1999 with much larger concrete box culverts that are 3 metre wide by 3 metre high. A total of 4 new box culverts are now installed at critical sections of the berm road that improve the natural coastal tidal exchange between the river, estuary and ocean, benefiting not just salmon but also other species including trout, invertebrates, birds and endangered mammals in the area. While this specific component of the project was funded by our Aquatic Ecosystems Restoration Fund with staff from our Restoration Centre of Expertise under PSSI, additional support from the Coastal Restoration Fund, the Fish and Wildlife Compensation Fund and the BC Salmon Restoration and Innovation Fund (BCSRIF) have contributed to the project’s overall success.

Additional benefits of restoring the Skwelwil’em Estuary include improvements to water quality and habitat resilience from climate events like storms and floods. Over time, fresh sediment deposited from the river will help to promote the return of marsh habitat which also increases the ability of the estuary to store atmospheric carbon and support species at risk within the area.

A history of collaboration – partnerships driving progress

This restoration project builds on decades of planning and partnership. Following the failed coal port proposal, the Squamish Estuary Management Plan was developed and signed in 1999 by federal, provincial, and local governments. In 2007, 673 hectares of the area was designated the Skwelwil’em Squamish Estuary Wildlife Management Area by the Province of BC and managed in partnership with Sḵwx̱wú7mesh Úxwumixw (Squamish Nation). By 2015, numerous restoration projects have been completed to re-establish the estuary as a thriving ecosystem, including:

Restoring 20 hectares of salt marsh, tidal channels, and upland habitat

Constructing over 25,000 m² of tidal channel habitat

Planting native vegetation and restoring eelgrass beds

Building pedestrian bridges to improve public access

The restoration of Skwelwil’em Estuary is a powerful example of how collaborative action can help restore critical salmon habitat to address the decline of Pacific salmon populations. As work continues, this project offers renewed hope for the Chinook salmon population in this area and the many species—and communities—that depend on them.

When the water flows back into the estuary, the ducks return, the seals follow, and the fish swim freely again, it becomes one giant ocean, not a divided system.