Innovation is key when it comes to tidal marsh restoration projects. Over the years, the Fraser River in B.C. has been highly modified through dredging and other human activities, changing its natural processes. As part of the Sturgeon Bank Sediment Enhancement Pilot Project, Ducks Unlimited Canada (DUC) is hoping to reverse some of those impacts through a unique project designed to rebuild tidal marsh resilience and support coastal flood protection.
Supporting an abundance of wildlife, the Fraser River Estuary is the last stop for migratory birds on their way to the far north. The largest salmon-bearing river in Canada, it is also one of the most productive bird habitats for migrating waterfowl and shorebirds in the country.
Led by DUC and partners, the recent completion of the first phase of the Sturgeon Bank pilot project will benefit fish, wildlife and people who use this important ecosystem.
A unique, customized approach
Approximately two million cubic metres of sediment are dredged each year from the Fraser River and taken by ship out to sea. Removed to ensure waterways do not become clogged and create navigation hazards, this material is now being repurposed for habitat restoration. Using a large temporary sediment delivery pipeline, this recycled sediment was distributed to key areas on Sturgeon Bank, allowing the natural process of waves, winds, and tides to distribute these sediments throughout the foreshore.
Careful planning is necessary for a project of this magnitude and the tide schedule and weather have a big impact on work activities, requiring the project team to adapt as conditions change quickly.
Lessons learned
Eric Balke, project lead and biologist for DUC in B.C. says there were many lessons learned which will be invaluable as they begin planning for phase two, slated for fall 2023.
“We were able to complete two of three planned sediment mounds and we consider the project a big success because of the innovative nature of the work and magnitude of the logistical obstacles we had to overcome to deliver sediment to Sturgeon Bank,” says Balke. “Now we look forward to seeing the results of these efforts as we work to restore this incredibly important tidal marsh habitat.”
Mobilizing the pipeline amid changing tides and high winds took significant time and planning and after several delays, Balke’s team was able to complete the inaugural sediment addition for this customized approach to habitat restoration. More than 11,000 cubic metres of sediment was added. Directing those sediments toward the shoreline will encourage the marsh to grow and flourish.
Benefits to this innovative habitat restoration
Beyond providing habitat for waterfowl and shorebirds, this restoration work on the Fraser River Estuary will help rebuild salmon habitat and can help reduce coastal flooding impacts to nearby communities by restoring this habitat back into a fully functioning tidal marsh.
“Our hope is that this pilot project will be replicated on a larger scale in the future, which could lead to transformational change and help these tidal ecosystems survive when sea-level rise threatens to drown marsh habitat,” says Balke.
The project is led by DUC in partnership with Raincoast Conservation Foundation, Tsawwassen First Nation, and the Lower Fraser Fisheries Alliance. It is funded by the BC Salmon Restoration and Innovation Fund through Fisheries and Oceans Canada and the Province of BC, with additional funding from Tsawwassen First Nation and the Vancouver Fraser Port Authority.
