Qwuloolt Estuary Restoration

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The Qwuloolt Estuary restoration project is a partnership between the Tulalip Tribes, Washington Department of Ecology, National Marine Fisheries Service, and U.S. Fish and Wildlife Service, in cooperation with the City of Marysville. The project encompasses 360 acres of Ebey Slough in the lower Snohomish River Estuary approximately three miles upstream from Puget Sound. The project will restore the historic and natural influences of the river and tides, creating a functional wetland complex connected to the broader Snohomish estuary.

ESA worked with the Qwuloolt partners to evaluate alternatives for reintroducing tidal action to the site, including full and partial breaching of levees and modifications of tide gates. The ESA team conducted geomorphic impact assessments, hydraulic modeling, sedimentation analysis, hydrology and hydraulics studies, and prepared a preliminary design for levee breaching.

ESA prepared plans, specifications, and permit applications for new channel alignments along Jones and Allen Creeks as part of the restoration. We are designing site features including additional tidal channels, berms, changes to stormwater infrastructure, and elevating a portion of a pedestrian trail on the east side of the project. Our planting plan will restore the marine riparian community around the perimeter of the site. We collected ecological data, prepared city, state, and federal permit applications for the entire project, and participated in public meetings to educate and involve the local community about this landmark restoration.

The several hundred acres of self-sustaining wetlands restored by the project are expected to provide habitat for a range of estuarine wetland species, including rearing habitat for juvenile salmon. The project removes barriers to Allen Creek and seeks to recover losses to natural resources injured by the release of hazardous materials from the Tulalip Landfill, enhancing the valued Puget Sound estuary.

Specialized Services

  • Channel and floodplain restoration design
  • Community outreach programs
  • Design specifications and construction bid packages
  • Environmental compliance documentation
  • Floodplain delineation
  • Habitat restoration and enhancement
  • Hydrologic and hydraulic modeling
  • Permitting assistance
  • Real-time data collection systems
  • Schematic and conceptual design
  • Sediment transport studies
  • Stormwater management
  • US Army Corps of Engineers
  • US Fish and Wildlife Service
  • Wetland restoration

Related images

ESA Flood Comparison for Qwuloolt