Welcome to the Lower Frew Levee Setback Project Virtual Open House.

King County, as a service provider to the King County Flood Control District, is working to reduce flood risks and improve fish habitat along the lower Tolt River.

The survey on the Share Your Feedback page will be open from March 9, 2023 to March 27, 2023. This Virtual Open House will remain open. 

The purpose of this Virtual Open House is to:

  • Share information about the project and the four project design alternatives being considered to reduce the risk of flooding for residents near the lower Tolt River and improve fish habitat.
  • We want to hear your thoughts about the project and the alternatives being considered.

Photo taken during the January 2015 flood event. Shows the Tolt River at 8,000 cubic feet per second (cfs), Lower Frew Levee project area, and the City of Carnation. 

Thank you for your participation!

We welcome your questions and comments. Your feedback will help inform the project design. We are committed to keeping you informed on project updates and will let you know about future opportunities to provide additional feedback. To sign up for project updates, visit our website at kingcounty.gov/LowerFrew.


Contact Sarah McCarthy, Project Manager, at sarah.mccarthy@kingcounty.gov or 206-477-4766.

How does this Virtual Open House work?

To provide feedback, there are survey questions on the Share Your Feedback page. Responses to public comments and questions will be posted on this virtual open house within 3 business days. Responses to private comments and questions will be responded to if an email address or phone number is provided.

All comments are considered public record. However, if you turn off the ‘Post Publicly’ button next to the comment box or survey question, your comments will not be visible to others.

Please join us and learn how King County, as a service provider to the King County Flood Control District, is working on a project that will reduce flood and erosion risks and improve habitat in and along the lower Tolt River. King County plans to remove the existing Lower  Frew Levee and construct a new levee set further back from the river. The recreational Tolt River trail will be rebuilt on top of the new setback levee.

Key Terms

  • Alternatives: Different project design options to achieve the project purpose, need, and objectives.
  • Cubic feet per second (cfs): The rate of water movement in a river or stream representing a volume of one cubic foot passing a given point in one second.
  • Culvert: A structure that channels water past an obstacle, such as a roadway or railroad prism.
  • Fish habitat: The aquatic environment and adjacent upland area critical for fish to live, breed, and grow during various life stages.
  • Floodplain: The relatively flat lands adjacent to a river, formed mainly of river sediments, that become inundated during periods of high flow, or flood.
  • Floodplain reconnection: Reconnecting rivers to their floodplain by removing structures such as levees, improves the natural function and ecology of rivers.
  • Large wood migration protection: Engineered structures created in rivers and floodplains designed to simulate naturally occurring log jams. Log jams help direct river flow and create forage and refuge habitat for salmon.
  • Levee: A raised structure designed and constructed to contain, control, or divert the flow of water to provide protection from temporary flooding.
  • One percent annual chance flood: A flood that has a one percent chance of occurring or being exceeded in any given year. This is also known as the 100-year flood.
  • River side channel: A smaller channel next to the Tolt River main channel to provide off-channel habitat.