WDFW, partners restore estuary habitat with completed Milltown Island Project
Intertidal marsh restoration in the South Fork Skagit River estuary creates habitat for juvenile salmon while adding amenities for waterfowl hunters and recreationists.
On an island just upstream from where the Skagit River enters Skagit Bay, Chinook salmon are nosing their way into habitat that has been largely inaccessible to fish for nearly a century. At the same time, hunters are accessing new boat landings and sites for waterfowl blinds that support outdoor recreation.
Located just west of Pioneer Highway between Conway and Stanwood, the Milltown Island Unit of Skagit Wildlife Area is a 322-acre site that the Washington Department of Fish and Wildlife (WDFW) acquired through a series of purchases in 1951, 1973, and 2024 to provide habitat for fish, waterfowl and other wildlife, and opportunities for hunting and other public recreation.
In October 2024, WDFW completed Milltown Island Estuary Restoration Project. Covering approximately 200 acres of the site, the project included lowering dikes and levees, excavating tidal channels and headwater ponds now filled with water during high tides, and building low-angle watercraft landing sites and raised mounds to support public access and use of the site for activities such as waterfowl hunting, kayaking, and bird watching.
“This site will provide diverse habitats for a wide range of fish and wildlife,” said WDFW project manager Jenny Baker. “The construction elements were designed to provide habitat primarily for salmon and other fish, but we also built tidal headwaters with shallow water areas for waterfowl and wading birds. We’ll plant large portions of the site with trees and shrubs, which will provide cover, food and nesting areas for birds, and food and building material for beavers.”
While fish had access to portions of the site already, monitoring data showed there was room to increase their access to intertidal estuary habitat. Adaptively managing restoration sites ensures benefits to fish and wildlife are maximized and, in this case, provided an opportunity to add recreational features. Restoration experts and recreational users guided the design.
The newly restored intertidal estuary at Milltown Island will benefit Chinook salmon by providing critical rearing habitat for juveniles as they migrate from freshwater to the salty waters of Whidbey Basin and Puget Sound. Juvenile Chinook that spend time in estuaries grow bigger and are better able to survive to adulthood. More Chinook, in turn, provide food for endangered Southern Resident killer whales.
A close partner during the restoration project has been the Skagit River System Cooperative (SRSC), which provides natural resource management services for the Sauk-Suiattle Indian Tribe and the Swinomish Indian Tribal Community.
“We’re looking forward to starting a three-year post-restoration effectiveness monitoring study in 2025,” said Mike Lemoine, SRSC Director of Research and Recovery. “Pre-restoration data suggested fish were having a hard time getting to the interior channels and I am hopeful that fish can now take advantage of more area.”
The project also builds on past restoration actions by constructing channels, shallow areas called tidal headwaters, and low planting mounds to create diverse habitats. This benefits a variety of other fish, shore birds and waterfowl, and mammals.
The project removed dikes to restore tides and river flows to the site so that water and sediment continue to create and maintain habitat into the future. Channels for salmon will also provide improved recreational access into the area, including for deploying duck hunting decoys and blinds near areas of shallow standing water. Several low angle landings will provide places for recreational visitors to more easily land a boat and walk onto Milltown Island.
“The new channels provide enhanced access to a larger portion of the island,” said Rick Billieu, Northwest Chapter Chairperson of Washington Waterfowl Association. “The elevated areas are good locations for wildlife viewing or hunting. Once the plant life returns, hunting opportunities should be greater than before restoration.”
Refer to our website for a larger version of this Milltown Island map showing estuary restoration project features.
Improving climate resiliency
The Milltown Island Restoration Project also supports habitat restoration goals and other objectives of the Skagit Wildlife Area Management Plan, which WDFW updated in 2024. This includes making Milltown Island more resilient to climate change impacts. The Skagit River carries a lot of sediment. Floodwaters will be able to spill onto the site through the additional dike breaches and deposit sediment. This will cause the site to aggrade (slowly raise in elevation) and potentially keep pace with sea-level rise.
Lastly, the project removed derelict farming debris from the early 20th Century and planted native shrubs and trees to improve habitat conditions. In the winter/spring following construction, WDFW and contractors are installing more than 31,000 willow stakes and 6,400 plants of other species including native trees and shrubs, along with leafy aquatic plants such as wapato, or broadleaf arrowhead, which will provide forage for waterfowl.
Planting is scheduled to continue October through November and March through April from 2025 until 2027, including some planting during waterfowl hunting seasons. WDFW will post signs and provide additional outreach to let hunters know when and where planting is happening.
A note for visitors to Milltown Island: The recent habitat restoration project resulted in softened soil and other hazards. Visitors should exercise extreme caution, especially during high water conditions which may obscure potentially hazardous areas. Additional changes to the site are expected over time as natural processes continue.
WDFW staff, contractors, and partners will be on the site periodically planting native vegetation to contribute to habitat quality and waterfowl forage, including during waterfowl hunting seasons.
Background on Milltown Island
Like the neighboring Island Unit, Milltown Island is located between Steamboat and Tom Moore sloughs in the South Fork Skagit River. The area is only accessible by boat, including from the nearby WDFW-managed Skagit Headquarters Unit water access area as well as a public boat ramp just upstream adjacent to the bridge in Conway. A small private ramp is also available at the end of Milltown Road.
Milltown Island was once entirely tidal marsh. Early homesteaders diked and drained the island and lived and farmed here for decades. But the loss of a bridge to the island in the 1970s, as well as dike breaches caused by flooding, left the site fallow and used primarily for boat-in waterfowl hunting in the fall and winter.
Between 1999 and 2014, initial dike breaches and tidal channels were constructed for the benefit of salmon and other fish and wildlife that rely on estuaries. However, much of the dike system was still in place and the site remained largely cut off from full tidal exchange and river floods. Channels were not well-connected to the main river sloughs where juvenile salmon travel as they make their way from upriver spawning areas to Puget Sound, and vegetation was largely dense stands of non-native reed canary grass and cattail that are not good for fish or other species.
To provide the maximum benefit for fish and wildlife, WDFW hired a design consultant, Environmental Science Associates (ESA), and began developing plans for the bigger project to remove dikes, create channels and low planting mounds, treat weeds, and plant native shrubs and trees. A technical advisory committee, WDFW staff, and a group of waterfowlers reviewed draft design elements.
“During design we pulled on the knowledge and experience of a group of technical experts including staff from the Skagit River System Cooperative, Upper Skagit Indian Tribe, Skagit Watershed Council, Ducks Unlimited, and Padilla Bay National Estuarine Research Reserve,” said Baker. “We also asked waterfowlers what kind of actions we could include that would support recreation. Low angle landings and siting mounds near the tidal headwaters were ideas to support recreational use of the site.”
In 2022 the design was completed and in 2023 permits were obtained to begin the project.
It was then time for WDFW to hire a contractor to complete this complex project. The project was awarded to TRICO Companies LLC, a construction company based in nearby Burlington. Work on the Milltown Island Restoration Project got underway in spring 2024 and was completed in early October.
The TRICO team barged in equipment and worked around tight tidal windows, strict ground pressure regulations, and the many other unique environmental factors found on the marshy island.
TRICO project manager Reilly Russell described the project as “a successful collaboration between WDFW, local talent, our innovative civil team, and dedicated shop crew to restore wildlife and salmon habitat here in the magic Skagit Valley.”
“The Milltown Island Restoration Project has certainly been a highlight of my career as a young project manager,” said Russell. “I am proud and thankful to have had the opportunity to be a part of this project that will help to revitalize habitat for wildlife in the South Fork Skagit River.”
Funding for the Milltown Island Restoration Project comes from multiple sources including:
- WDFW and Washington State Recreation and Conservation Office (RCO) Estuary and Salmon Restoration Program (ESRP)
- RCO Puget Sound Acquisition and Restoration Program
- U.S. Fish and Wildlife Service (USFWS) National Coastal Wetland Program
- NOAA Restoration Center Transformational Habitat Restoration and Coastal Resilience Grants under the Infrastructure Investment and Jobs Act
What comes next for Milltown Island
Looking ahead, WDFW and project partners will continue monitoring the restoration project site to evaluate how fish — particularly Chinook salmon — are using the new habitat. WDFW and SRSC staff will also work to manage and remove invasive weeds and continue planting willows and other native vegetation.
In the decades ahead, the hope is that abundant fish will use channels that wind through dense stands of shrubs and trees, beavers will be active on the site creating a mosaic of wetlands and open water habitats, a host of birds and other wildlife will thrive, and people will continue to access the site to hunt, bird-watch and enjoy an evolving island in the estuary.
Refer to this webpage for more information on estuary restoration projects on WDFW-managed lands.
WDFW manages more than 1 million acres of land and hundreds of water access areas throughout the state. By actively managing lands, restoring habitats, and preserving wild places, the Department serves as stewards for Washington’s natural places, protecting the state’s land and water for wildlife and people.
