Safe and flood-prepared communities.
Abundant salmon and steelhead.
Strong, nature-based economies.
Welcome to the Office of Chehalis Basin, home of the Chehalis Basin Strategy
If you came to this page looking for the Chehalis Basin Strategy, you’re in the right place! Moving forward, our website and social media channels can be found under the name Office of Chehalis Basin.
The Office of Chehalis Basin, housed within the Washington Department of Ecology, is funding, coordinating, and implementing projects that are reducing flood damage and restoring aquatic life. As flood-damage reduction and aquatic restoration work expands throughout the Chehalis River Basin, you can look to the Office of Chehalis Basin for updates and opportunities to get involved.
The Chehalis Basin Strategy is still here: It’s the long-term, integrated plan being developed by the Chehalis Basin Board for release in 2026 — it includes projects and plans that will help guide the future of the Basin.
How we’re taking action
Helping residents and communities protect homes and businesses from flood damage
Working with landowners to slow harmful erosion and restore habitats for salmon and other aquatic life
Preparing the region for more frequent major and catastrophic flooding
Quick links
What happens in the Chehalis Basin matters for all of Washington, and beyond.
The 2,700 square mile Chehalis Basin in southwest Washington reaches from the forested, rolling hills of the upper Chehalis River, to fertile farmland and valleys, and finally to the marshes and beaches of the Pacific Coast.
The Basin’s rich history and present-day reality are shaped by the ancestral heritage of numerous Tribes. Today, the land continues to be stewarded by the Confederated Tribes of the Chehalis Reservation and the Quinault Indian Nation, which has treaty rights to fish, hunt, and gather in the Chehalis Basin.
Salmon and Steelhead
The Chehalis Basin is the only major river basin in Washington with no salmon species listed as threatened or endangered, although the federal government is considering a petition to list Chinook salmon.
Nature-based economies
The region’s agricultural community alone brings in $650 million every year for the state of Washington. Forestry and fishing have also long served as economic engines within the Chehalis Basin.
U.S. Interstate 5
I-5, the West Coast’s key transportation corridor for commerce, food supplies, and public health, runs directly through the heart of the Chehalis Basin and its floodplains.
140+ partner projects are making a difference
Montesano Wastewater Treatment Plant: protecting communities from sewage spills during floods
- The Montesano Wastewater Treatment Plant was in serious danger of being breached during flooding, potentially sending millions of gallons of raw sewage all the way to Grays Harbor.
- Natural, log-based protections were installed in the river.
- During January 2022 floods, the protections saved the community from $40 million worth of damages.
Smart investments that work
Our partners use science-based innovations to make smart investments in projects that work. We have a track record of implementing strategies that pay off—and by coordinating efforts across the Basin, we’re having an even greater impact.
Pump station and levee improvements at the Chehalis-Centralia airport
Initial investment: $1.1 million
Return on investment from protected jobs and revenue during January 2022 flooding:
What’s new
The latest news, announcements, and publications from the Office of Chehalis Basin.
Restoration in Action: Helping Habitats and Communities