Project Location:
Redmond, Washington

Client: Washington State Department of Transportation

Construction Cost:
$2.5 million

Wilder’s Role: Prime

Construction Period: 3/99 – 7/01

Project Highlights

300 meters of new creek alignment    Dewatering   260 log boles   Soil erosion control

Wilder is in the midst of a challenging project in Redmond, WA, named Bear Creek Enhancement.  The intent of the project is two fold.  First, relocate the creek to accommodate future 520 expansion.  Second, incorporate fish habitat and bank stabilization features into the new channel. Bear creek is host to an array of fish species including Chum, Chinook, and Sockeye salmon.  With the advent of salmon being named on the endangered species list, this project has drawn a wide range attention from King County and greater Puget Sound.

A 300 meter section of Bear Creek is being detoured and rebuilt.  The new channel will have five curving meanders.  Most of the old channel will be completely abandoned and backfilled.  Logjams will be constructed at the intersections of the new and old channels allowing water to fill into two pond-like channels.  A maze of log structures is included in this complicated project.  Over 260 log boles averaging 16 feet in length and approximately 200 other logs averaging 15 feet in length are to be placed in an interlocking fashion.  This requires a gentle touch for excavator-operators.  The dewatering system must be continually monitored and includes 3-18,000 gallon tanks, a sand filter, a particle filter and over ½ mile of discharge pipe.  The surrounding area will be re-vegetated with a large variety of native trees and shrubs to sustain a healthy habitat and a successful plant establishment period.

Wilder is using best management practices to protect the creek. A new method of soil erosion control was used on this project.  The polyacrylamide, PAM was sprayed onto bare soil. As part of the on-going Stormwater Pollution Prevention Plan, the turbidity of the stream is measured and logged daily, checking for a 5 NTU increase above background.