Blue Heron Slough Conservation Bank restores and preserves intertidal, wetland, and upland habitats in Snohomish County near Port Gardner Bay, Washington. The site encompasses diverse habitat types, including tidal marshes, estuarine wetlands, riparian corridors, and upland transitional areas that collectively provide critical nursery and migratory habitat for Pacific salmonids (Oncorhynchus species), shorebirds, and other native fish and wildlife that depend on healthy Puget Sound ecosystems.

Positioned at the ecological intersection of freshwater rivers and marine estuaries, Blue Heron Slough provides essential ecosystem services that support the full life cycle of anadromous fish species. Juvenile salmon rely on the productive wetland and estuarine conditions to rear before migrating to the ocean, while adult fish utilize the site as a transitional corridor during upstream spawning migrations. The tidal influence and nutrient-rich waters create an optimal foraging habitat for salmonids while supporting specialized plant communities and invertebrate communities that form the foundation of this productive food web. Shorebirds and waterfowl depend on the site’s diverse habitat structure for breeding, feeding, and stopover habitat along the Pacific Flyway.

Blue Heron Slough plays a vital role in maintaining ecosystem health and salmonid productivity across the Snohomish River estuary. The restored and preserved habitats strengthen connectivity between freshwater river systems and marine environments, supporting salmon population recovery efforts and sustaining the broader ecological network of Puget Sound. Long-term stewardship ensures that tidal and hydrological processes remain fully functional, invasive species are controlled, and native plant communities are maintained to maximize benefits for salmonids and other fish species over time.

The Bank was approved by the U.S. Army Corps of Engineers and the Washington Department of Ecology to provide salmonid mitigation credits. Currently advancing through wetland mitigation bank entitlement with both agencies, Blue Heron Slough is positioned to offer combined wetland/waters and salmonid credits upon full certification. This integrated credit approach provides a streamlined and flexible mitigation solution for projects with overlapping impacts to aquatic habitats and salmonid-bearing waters, simplifying compliance for developers and agencies across the Puget Sound region.

Available Credit Types

Download the service area map and KMZ file below:

Service Area Map | KMZ