Friday, June 26, 2015

A gentler trip for our Hylebos friends

Michael Allende

The small, 90-year-old culvert in the West Fork Hylebos Creek
will be replaced with a larger one that will present fewer
obstacles for migrating fish.
While it would be amazing to see a fish take on a Tough Mudder course, they’ve got enough to worry about so we’re going to help them out. A project starting June 29 will make the lives of Chinook, coho, chum salmon and their friends in the West Fork Hylebos Creek easier.

The creek, which runs under State Route 99 in Federal Way, has a small, 90-year-old box culvert that needs to be replaced. While we’re at it, we’re going to realign the creek to change it from a fast-moving straight-shot for the fish to a gentler, meandering trip. Think of it as changing a water slide from one of those crazy, vertical fright-fests to an enjoyable, calm lazy-river ride.

Revamping West Fork Hylebos Creek will slow the
water flow, giving wildlife a gentler trip through
the waterway.
Reshaping a creek isn’t easy, and it’s going to require a full weekend closure of SR 99 between Southwest 356th Street and South 373rd Street. About 100 feet of roadway has to be removed to install the new culvert. So during the closure, drivers will be detoured to I-5. It’s about 6-mile detour that will add about 10 minutes of travel time. A shuttle will also be available to take pedestrians and cyclists around the roadblock.

Part of our responsibility in building and maintaining roads is being sure that the environment around those roads is also being cared for. In this case, the culvert is just 6 feet by 6 feet, making it difficult for fish to maneuver through as debris regularly creates obstacles. We’ll be replacing that culvert with a 10 feet-by-20 feet one that will give fish more space to swim through and cut down on the cost of maintenance from having to clear out debris.
Frogs, fish and other wildlife are clearly eager to try out the
re-aligned West Fork Hylebos Creek.

At the same time, we’re going to slow down the water flowing through the stream by realigning and re-grading the creek. Water rushing through has scoured some of the creek bed, creating significant drops that make it impossible for fish to migrate through. This work will create a gentler slope and will open up access to five additional miles of stream, allowing fish to eventually make their way into the West Hylebos Wetland Park.

Finally, we’ll be doing a bit of gardening. We’re going to remove the non-native trees and shrubs in the area and replace them with native species like Oregon ash, Sitka spruce, western red cedar, black twinberry, Indian plum, red osier dogwood and salmonberry.