Emergency bridge repairs to shut down busy Mill Creek road this weekend

Getting in and out of Mill Creek is going to be rough this weekend. The city is shutting down one of the busiest roads in Snohomish County, 164th St. SE, for emergency bridge repairs.

164th St. SE connects I-5 and Mill Creek. Nearly 40,000 vehicles a day use the road during the week. Up to 30,000 vehicles a day use it on weekends. Mill Creek is not going to shut it down without a very good reason, and it has one.

Failed bridge support prompts emergency closure in Mill Creek

A small bridge over North Creek, just before SR 527, a bridge that most people don’t even realize is there, needs emergency repairs. Dan Carmody, city engineer of Mill Creek, told me a recent inspection found a significant problem in one of the wooden columns that holds up the bridge.

“We hired a structural engineer to go out and do a full review of the bridge, and it was discovered that the column had completely failed,” he said.

What does “completely failed” look like? It is scary.

“They drilled into the wood column, and on the outside was two inches of wood,” Carmody said. “The inside was completely a rotten void. It’s bowing out, and the column’s actually expanding. All that kind of stuff.”

The wooden column, which is one of about 30 holding up the 59-year-old bridge, wasn’t capable of carrying any weight. Mill Creek immediately closed the right lane of eastbound 164th St. SE to take the load off the column and keep the bridge from failing.

Now it’s time to fix that column. To do it, the city is shutting down both directions of 164th St. SE from 9 p.m. Friday to 4 a.m. Monday. The city said this is the best option to reduce the impact to the community.

“We were originally looking at doing a temporary fix and coming back in the summer and doing a permanent one, but then it turns out that it would take the same amount of time to do the permanent fix as it would to do the temporary one,” Carmody said. “We would rather not inconvenience the public twice.”

Targeted bridge repair could finish in one weekend instead of two

The plan is to finish the work over two full weekend closures, the second of which is scheduled for next weekend, but Carmody is hopeful all the work will get done this weekend.

The other option was to close one lane in each direction of the bridge for about a month.

What’s the fix look like?

“We are digging down and driving a pile right outside of the bridge,” Carmody said. “Then taking that pile, sticking it through the edge, and basically resting the bridge on it. We’re replacing the column, but we don’t have to touch the bridge deck.”

It’s a really surgical fix of the bridge. Think cavity fill, not a crown.

There are long-term plans to replace all of the old wooden columns and bridge deck, but that is years away.

North Road detour could mean 10- to 15-minute delays

I asked Carmody what he expects for delays or congestion during the work.

“I don’t anticipate there being too many delays,” he said. “There may be 10- to 15-minute delays, but it would just be traffic going in a different pattern. I don’t think there’s going to be huge backups. We’re hoping people get this information soon enough that they can go ahead and take alternate routes.”

There will be local access to the homes, apartments, and the church near the bridge, but most traffic will be diverted to North Road. Both sidewalks will also be closed.

The final price tag for this emergency work hasn’t been determined.

I joked that most people don’t even know there’s a bridge there, and I’m serious. I drive over this bridge every day. It’s only 28 feet long. The only clue it’s a bridge is the load restriction sign just before it.

And kudos to Mill Creek for jumping on this. The city found out the column was bad on Oct. 14. Action was taken immediately, and the fix could be done in about a month.

Chris Sullivan is a traffic reporter for KIRO Newsradio. Read more of his stories here. Follow KIRO Newsradio traffic on X.

Follow @https://twitter.com/newsguysully