A winter view of Mill Creek
A winter view of Mill Creek

 

In the vicinity of Mill Creek and Savage Creek on the south side of the Skagit River, Seattle City Light has acquired 212 acres for conservation purposes. SCL has been working with SRSC and Skagit County to restore the properties, including building demolition, riparian and floodplain plantings, culvert removals, and scoping the realignment of the South Skagit Highway within the project area.

The South Skagit Highway road prism completely isolates 62 acres of floodplain, disconnects and blocks fish access to 5.2 acres of wetlands, and significantly degrades hydrologic and fish connectivity to an additional 21.7 acres of slough and wetland habitat. Approximately 900 feet of Savage Creek runs in the highway ditch. Savage Slough flows under the highway through an undersized culvert that is periodically blocked by sediment from Mill Creek during floods. The Mill Creek Bridge is undersized resulting in numerous maintenance projects over the course of many years, including dredging and channelization.

The proposed project will evaluate several project alternatives and complete preliminary design work for the preferred alternative. Alternatives will be evaluated based on engineering feasibility, cost, habitat benefits and risks. The identified alternatives include 1) no action, 2) preserve the existing highway footprint with modifications, or 3) relocate approximately 1.5 miles of the highway outside the existing Skagit River floodplain. Implementation of a restoration project would provide additional habitat for all salmonid species.

Bridge crossing at Mill Creek.
Bridge crossing at Mill Creek.

 

Project Status/Timeline
The feasibility study is complete. SRSC is working to secure funds for final design and construction.

Primary Project Contact
Devin Smith –Senior Restoration Ecologist

Funding Sources
SRFB – Washington Salmon Recovery Funding Board
SCL – Seattle City Light

Project Partners
Seattle City Light
Skagit County