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NE Old Cascade Highway Roadway and Drainage Improvements

Major work completed; guardrail installation in October 2023

Status update

August 17, 2023

Crews have successfully completed the major work on both sides of NE Old Cascade Highway.

We will return in October to install guard railing above the new box culvert and to finish other minor work.

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Overview

This project improved traffic safety and made NE Old Cascade Highway in Skykomish, Washington better equipped to handle flooding. The county removed and replaced four worn out culverts under NE Old Cascade Highway, stabilized a steep slope/slide area, and cleared out more than 3,000 feet of roadside ditches. One large box culvert replaced two of the smaller culverts on the west side of the East Fork Miller River. Work also included creating two “dead end” turnarounds where the NE Old Cascade Highway ends on both the east and west side of the East Fork Miller River.

The turn arounds are necessary because heavy storms in 2011 took out NE Old Cascade Highway adjacent to the historic Miller River Bridge. The storms also carved out a new route for the East Fork Miller River. The river used to flow under the bridge. Now the river now flows where the highway used to be. The county also repaved the road after the safety improvements and turn arounds were completed.

About the project

Replacing pipe culverts

The county replaced four (4) worn-out pipe culverts, stabilized an active slide area, and cleaned the roadside ditches.

When pipe culverts under the road fail the water has nowhere to go except over the roadway. When too much water floods onto the road, it can cause the asphalt to crumble and wash away. Replacing old culverts improves safety by preserving the roadway.

  • West leg: NE Old Cascade Highway
    Contractor crews replaced two (2) old, worn-out metal pipe culverts with one (1) large concrete box culvert. The box culvert will keep water off the highway when Money Creek floods and water has no place to go.
  • East leg: NE Old Cascade Highway
    Contractor crews replaced two (2) cracked and rusted metal storm water pipe culverts with new pipes. The replacement pipe culverts will be similar in size to the existing, worn-out pipes.

Stabilizing hillside and clearing ditches

Stabilizing the active slide area on NE Old Cascade Highway helps prevent mud and debris from tumbling down and impacting the roadway.

Cleaning out ditches along the east leg of the roadway helps send more water to the right place, which reduces the risk of more flooding and roadway damage.


Aug. 11, 2023 – A crew member stabilizes an active slide area using an excavator along NE Old Cascade Highway.

Traffic safety

The county installed two “dead end” turnaround locations where the east leg of NE Old Cascade Highway and west leg of NE Old Cascade Highway meet the East Fork Miller River. We also repaved the roadway on both sides of the river.

  • East leg: NE Old Cascade Highway
    Crews built a "hammer" style turnaround. It is shaped like a hammer to allow large emergency vehicles, like fire engines, to turn around.
  • West leg: NE Old Cascade Highway
    This end of the road received a “bulb” style turnaround cul-de-sac. It now looks like a traditional rounded cul-de-sac that most people are familiar with.

Building clear turnaround points reduces hazards and makes the area more secure for drivers. Repaving three (3) miles of damaged road provides a smooth surface for years to come.

Location map

There were two worksite locations, divided by the East Fork Miller River.

  • West leg: NE Old Cascade Highway: Between East Fork Miller River and SR 2 (Steven Pass Highway).
  • East leg: NE Old Cascade Highway: Between East Fork Miller River and the Skykomish city limits

Project location map.

Larger view (78KB)

Project timeline

  • Construction begins – Mid-June 2023

  • Two full road closures – Wednesday, July 19 and Wednesday, July 26. Each closure is expected to last up to eight hours.

  • Construction ends – Late summer 2023

Project budget

This project is funded by Federal funding sources. The total cost is $5,050,000.

Project documents

Photos

Aug. 16, 2023 – A crewmember paves the damaged NE Old Cascade Highway. Now three miles of roadway will have a smooth surface for years to come.


The new box culvert is successfully installed on NE Old Cascade Highway just after the railroad tracks. The box culvert will keep water off the highway when Money Creek floods and water has no place to go.


Crane work on NE Old Cascade Highway

King County closes NE Old Cascade Highway to use a crane to lower sections of a large new culvert under the road. This new culvert will help prevent flooding in nearby Money Creek. Photo taken on July 19, 2023


Crane work on NE Old Cascade Highway.

July 19, 2023 - King County closes NE Old Cascade Highway to use a crane to lower sections of a large new culvert under the road. This new culvert will help prevent flooding in nearby Money Creek.


Rusted and damaged culvert pipe.

April 21, 2023 – One of the smaller culverts on the east side of the East Fork Miller River on NE Old Cascade Highway is rusted and damaged. Crews will replace it in late spring 2023.


Engineer surveys the location.

April 21, 2023 - A King County engineer surveys the location of one of the old culverts that needs to be replaced on the west side of the East Fork Miller River. A large box culvert will replace this culvert and one other culvert just north of the railroad tracks on NE Old Cascade Highway.


NE Old Cascade Highway looking east.

Looking east: NE Old Cascade Highway approaching the east side of the East Fork Miller River. King County will replace the temporary road closure with a permanent turn-around.


NE Old Cascade Highway looking west at road closure signs.

Looking west: NE Old Cascade Highway approaching the west side of the Miller River. In 2011, King County Road Services closed the highway on both sides of the Miller River after a major storm completely washed out the road. The storm also permanently changed the course of the river.

Frequently asked questions

Heavy storms in 2011 washed out 160 feet of NE Old Cascade Highway, and changed the course of the East Fork Miller River. King County set up temporary road closures on both sides of the river to keep visitors out of the area. Now it is time to build permanent turnaround points in the area.

It would cost up to $60 million to replace the 100-year-old historic Miller River Bridge and approaches on both sides of East Fork Miller River. The county received $4.5 million from the Federal Emergency Management Administration (FEMA) to improve flood resilience and traffic safety in the area. The funds will be used to install new culverts and other features that will help prevent heavy storms and floods from damaging the area in the future.

The historic Miller River Bridge will remain in place. This project does not remove the bridge. The river changed course in 2011, and no longer flows under the bridge. The county may eventually remove the historic bridge in the future. Removing the 100-year-old bridge requires a cultural resource and historic preservation review before it can be dismantled. Funding for the review and the costs involved with removing the very old bridge is not currently available.

The road washed out in 2011. It took several years to design the project and secure funding from FEMA. In addition, the project required the county to get easements from local property owners and, in some cases, purchase land. All of this takes time to complete.

No. There will always be access to both campgrounds and the National Forest. The one exception is when crews close NE Old Cascade Highway to make room for a full-size construction crane. The crane is needed to install large concrete sections of the box culvert. We expect no more than two full road closures, each closure will be up to four (4) hours long.

Any community member or resident that wishes to obtain pavement grindings from the project contractor would first need to obtain a grading permit from King County’s Department of Local Services, Permitting Division. The permitting process determines if it is safe to repurpose the old asphalt for private use. Asphalt grindings are considered hazardous waste that must be re-processed before they can be recycled for private use.

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