The Middle Boise Creek - Stream Restoration Project #2 was completed in 2018. It is one of several salmon habitat restoration projects planned or implemented by King County on Boise Creek. The goal of the project was to increase rearing and refuge habitat availability and complexity for Chinook and coho salmon and steelhead, in accordance with the 2018 Puyallup and Chambers Watersheds (WRIA 10/12) Salmon Habitat Protection and Restoration Strategy.

Similar to much of Boise Creek through the Enumclaw Plateau, the stream channel through the project area had been straightened, providing little opportunities for complex habitat formation such as pool, off-channel habitat, and wood accumulation. The restoration project added a secondary channel on the south side of the stream with several connections to the main channel. Mature trees were preserved where possible in order to maintain shade and wood supply for the stream. Pools were excavated, large wood was installed, and stream gravel was placed in the new channel bed. On the north side of the stream, an existing farm road was moved away from the bank and fenced, allowing for a riparian buffer to be planted and protected from grazing cattle. Overall, the completed project provides 1.3 acres of new aquatic and floodplain habitat for salmonids, in addition to enhanced riparian buffers.

Boise Creek is the largest salmon-producing tributary to the White River downstream of the Buckley Diversion and Mud Mountain Dam, which makes salmon habitat restoration in this largely agricultural area critical. The project is a successful example of finding a beneficial balance between agriculture and habitat restoration. The project focused on a section of the Agricultural Production District (APD) that is non-farmable. The project team worked with the landowner to keep construction materials and practices compliant with organic farming policies (e.g., fence materials, organic grass seed, and avoiding use of herbicide). Finally, the project moved the farm road away from the oversteepened stream bank which had previously posed a fall hazard for cattle moving along the road and water quality issues for the stream.

Project photos

Before

After

Project location

Project benefits

• Increase the amount and availability of salmon habitat by widening the stream channel and adding a secondary channel.
• Improve rearing and refuge habitat for juvenile salmon by excavating pools and adding wood and gravel.
• Improve shade, support the aquatic food web, and protect water quality by planting native trees and shrubs.
• Build upon other restoration projects completed in Boise Creek in recent years.
• Maintain existing organic farm operations and relocate a farm road away from an oversteepened bank.

Project funding sources

• King County Water and Land Resources Division
• Washington State Salmon Recovery Funding Board Grant
• King County Flood Control District Cooperative Watershed Management Grant
• King County Conservation Futures Tax

Project documents

• Middle Boise Creek Van Wieringen Stream Restoration Project Design Alternatives Analysis - January 2017 (7MB)
• Final design (11.2 MB)
• Project photos (3.3 MB)

For more information about the The Middle Boise Creek Van Wieringen Stream Restoration Project, please contact Sarah McCarthy, Project Manager, King County Ecological Restoration and Engineering Services.