Chehalis Basin Strategy Studies & Publications

The Chehalis Basin Strategy is informed by policy and science—from project design to ongoing evaluation—allowing us and our partners to adapt and put investments toward the best use.

Browse the studies and publications below to learn more about the science behind the Chehalis Basin Strategy, and revisit collaborative meetings and workshops through the years.

Looking for something you don’t see here? View the Washington Department of Ecology’s Publications page for the Chehalis Basin.

Featured Materials

Proposed Chehalis River Dam Environmental Review


State environmental review
Federal environmental review

Local Actions Non-Dam Alternative


Briefing Book

Skookumchuck Dam Study


April 2023 webinar recording

Frequently Asked Questions About January 2022 Flooding


Flooding FAQ

Chehalis Basin Board Public Meetings


Board website with downloadable meeting materials

Chehalis Basin Strategy E-Newsletters


Newsletter archive

Public Meeting Recordings and Materials

The Local Actions Non-Dam (LAND) Alternative is a collaborative, community effort to develop an approach to reduce flood damage in the Basin that could be implemented as alternatives to, or in addition to, the Chehalis River Dam proposed by the Flood Control Zone District. Join the Office Chehalis Basin and key partners for a one-hour informational update on the current options under consideration.

Watch the February 8, 2023 webinar recording.

The Skookumchuck Dam is over 50 years old, and the power plant it was built to serve is shutting down in 2025. The Office of Chehalis Basin has been working with partners to examine possible futures for the dam as part of its Skookumchuck Dam Study. Join us for a one-hour webinar as we break down the Phase Two study results and what they could mean for the Skookumchuck River and neighboring communities.

Watch the April 13, 2023 webinar recording

Tune into this one-hour webinar to learn about the resources and assistance that’s available through the Chehalis Basin Strategy. You’ll hear about assessing flood risk, planning support, floodproofing, and much more.

Watch the November 30, 2022 webinar recording.

The Chehalis River Basin Flood Warning System is a public website with forecasts, inundation maps, and real-time river level data and alarms that could save your life. Tune in for a training from the Chehalis River Basin Flood Authority.

Watch the November 2, 2022 webinar recording.

Flooding is a fact of life in the Chehalis Basin, and we know that its danger and urgency is intensifying. That’s why the Chehalis Basin Strategy is putting solutions in place to protect people, fish, and wildlife now, while also planning for a more resilient future. Learn how the Office of Chehalis Basin is taking new climate change projections into account, and what it means for you in the Basin.

Watch the October 25, 2022 webinar recording.

As part of the Local Actions Non-Dam Alternative (LAND) effort to develop and evaluate a comprehensive, Basin-wide flood damage reduction approach, the LAND Steering Group met with public officials and community members with interest, expertise, and direct experience with flooding damage. This Values Planning Process kicked off the discussion about flood protection needs and opportunities throughout the Basin.

To better understand Chehalis Basin ecosystems, the Aquatic Species Restoration Plan Steering Committee hosts symposium events to share the scientific knowledge that has come from Chehalis Basin Strategy investments and to provide a venue for feedback and ideas about aquatic habitat restoration.

View all Symposium materials.

On March 9, 2022, the Office of Chehalis Basin hosted an informational webinar so the public could learn more about its work to study ways in which the Skookumchuck Dam might be improved for flood damage reduction and/or fish passage.

In fall 2020 and spring 2021, the Office of Chehalis Basin hosted a series of public meetings to connect with and hear directly from Chehalis Basin residents and others about choices related to reducing flood damage and restoring aquatic species habitat that will impact the future of the Basin.

Learn more by viewing the meeting recordings and presentations from the public meetings:

Technical Studies

Aquatic Species & Wildlife Studies

The Chehalis River and its tributaries are home to some of the most culturally- and ecologically-important species in the Pacific Northwest, including seven types of salmonids (including steelhead, Chinook, coho, and chum salmon). The Basin also supports the highest diversity of amphibian species anywhere in the state. Read the following studies to learn more about aquatic species and other wildlife in the region:




To learn more about ongoing monitoring efforts that support the Aquatic Species Restoration Plan (ASRP) program, read the latest reports from study leads, linked below.

Climate change is already impacting the Chehalis Basin environment and communities and is predicted to continue to influence the region through more frequent, intense flooding, warming water temperatures, and degrading habitat for salmon and other aquatic species. Read the below studies to learn more about climate change in the Basin:

Chehalis Basin Strategy Program Studies and Reports

A flood retention facility, which would include a dam and fish passage facilities on the Chehalis River as well as airport levee improvements, has been proposed by the Chehalis River Basin Flood Control Zone District as a potential project to protect some Basin communities from large-scale, catastrophic flooding. The below links include environmental reviews, studies, and technical reports which are being used to inform a final decision about whether the facility is constructed:

Environmental Impact Statement reviews

Planning and evaluation analyses

Erosion in the Chehalis Basin is made worse by frequent flooding. In some situations, it poses serious risks to property and structures, and can diminish habitat for salmon and other aquatic species. Learn more about erosion management analysis through the studies below:

Steering Group Materials

View most recent meeting materials and presentations from the following Steering Groups: