Stream Crossing Projects for Fish Passage

South fork cedar slideshow

See slideshow of fish passage project on the South Fork of the Cedar River.

Existing culverts will be upgraded, replaced or removed to enable fish passage during all natural flow conditions. Since 2000, 12 fish passage barriers have been removed and four others have been prioritized for future work.

By evaluating the increase in available habitat resulting from the removal of each management-related fish blockage, we have prioritized our list of culverts blocking fish passage. Using established design criteria developed by Washington Department of Fish and Wildlife (WDFW) and others, fixing these problems is also simple and relatively cost effective.

Taylor siphon

Taylor siphon is now suspended above Webster Creek, allowing fish passage.

Fish passage projects along Webster Creek
In 2001 we replaced a culvert on the 10 Road that was blocking fish passage with a bridge. In 2007 we removed the Taylor siphon, a large clay pipe that was partially buried in the streambed and was blocking fish passage. We then suspended a new pipe over the stream, restoring the natural hydrology. King County replaced a culvert on the Kerriston road in 2005 with a bridge allowing fish upstream to the natural gradient break that likely limits their distribution. These three projects increased available kokanee spawning habitat by approximately 1900 feet (almost doubling the available spawning habitat) and helped restore the natural movement of sediment in the stream.

See map of stream crossing projects for fish passage (pdf).

Stream bank stabilization
These photographs illustrate the 10 Road fish passage project on Webster Creek, before and after the bridge was installed.
See Webster Creek stream bank stabilization photos (pdf).

Controlling invasive plants
We are controlling invasive plants along Webster Creek, including Bohemian knotweed, Himalayan blackberry, and English holly.
See map of Webster Creek invasive plant control projects (pdf)

Conifer underplanting
We implemented an underplanting experiment to evaluate different conifer tree species and treatment types in the Webster Creek riparian forest.
See Webster Creek conifer underplanting report (pdf)