Project overview
Contractor crews working for WSDOT installed a 10-foot, corrugated metal pipe under State Route 410 to allow Dry Creek to pass beneath the roadway along its new channel. This is the second part of emergency repairs following a debris flow in fall 2022, which permanently changed the course of Dry Creek and overwhelmed a 24-inch culvert.
Work to increase stream capacity at Dry Creek began in February 2023, when three overflow culverts were installed to augment the existing 24-inch culvert approximately two miles north of the road to Crystal Mountain Ski Resort (milepost 55). This temporary fix reduced the risk of flooding damage to the roadway until the larger culvert was installed in fall 2023.
What to expect
Major construction is complete and no traffic control is expected at this time.
A 10-foot, corrugated metal pipe was installed beneath State Route 410 to allow Dry Creek to pass beneath the roadway along its new channel following a debris flow in November 2022.
In early November 2022, the area around Dry Creek experienced several inches of rain over several days resulting in a Nov. 5 debris flow that covered State Route 410. The roadway was blocked for several hours with mud, rocks, trees and boulders several feet deep and the road's west embankment was damaged.
Crews were able to clear the roadway, however, Dry Creek had shifted to a new channel that flows into an undersized 24-inch culvert, rather than the larger 4-foot concrete culvert it previously flowed through. The previous channel is permanently blocked by debris located outside WSDOT’s right of way on U.S. National Forest land. Dry Creek's new channel to the smaller culvert increased the risk of roadway damage or washout.
WSDOT determined that a two-stage emergency project was needed, first to minimize the flood risk from Dry Creek, and the second to install a longer-term solution that could result in a full roadway closure.
To maintain access to recreational and emergency access to Crystal Mountain Ski Resort and other businesses and residences, we installed temporary culverts beneath SR 410 in spring 2023. Then in fall 2023, we installed a 10-foot culvert under SR 410.
