Demolition of cracking 520 project column to begin soon

Nov 29, 2022, 5:11 AM | Updated: 5:13 am

Ramp support needs to be replaced...

A construction company needs to replace the SR-520 concrete pier cap that resides above I-5 in Seattle, which inspectors found to have cracks and holes during an October inspection. (Courtesy of WSDOT)

(Courtesy of WSDOT)

We found out earlier this month that a concrete column built just this year on the State Route 520 project is already crumbling and needs to be replaced.

The problem was obvious as soon as the wooden forms were removed from the pier in October.  The concrete was breaking off. Re-bar was exposed. And the cracks were large. There was no doubt it would have to be rebuilt.

SR 520 ramp closed through February for vibration testing

“We’ve been working with the contractor on a rebuilding plan to determine the best possible way they can go out there and take that crossbeam down and rebuild it,” the Washington State Department of Transportation’s (WSDOT) Tony Black said.

Black said the column is fine. It’s the top cap that needs to be replaced. A demolition plan should get underway in a few weeks, and the entire rebuild should be done before the end of the year.

“It will likely take a few days, and it will likely be at night,” Black said.

I promised westbound 520 drivers that they would get their second lane to southbound Interstate 5 back early next year. Will this work delay that from happening?

“That lane reduction wasn’t just for the concrete pier,” Black said. “It was mostly for the work zone areas around there.” That lane restriction should be eliminated by the end of February.

The other big question is, who will pay for this mistake? WSDOT said the contractor will eat the cost.

New ‘ramp support’ over I-5 needs to be replaced

Just a reminder of what WSDOT is doing here. This column will help support a new concrete flyover ramp connecting the 520 and the I-5 Express Lanes. It will be a reversible lane that will switch with the express lanes. It will go westbound 520 to southbound I-5 in the morning and northbound I-5 to eastbound 520 in the afternoon.

It is scheduled to open in 2024, about the same time as the Montlake Lid project wraps up.

This reversible lane will begin as a bus-only lane, but it will convert to an HOV lane for all vehicles when the 520 connection to I-5 is complete in about nine years.

Check out more of Chris’ Chokepoints.


i-90 state patrol chains...

Chris Sullivan

Pack your chains for snow: State Patrol targeting big rigs on I-90

The State Patrol is on the prowl across I-90 and other mountain passes, making sure truck drivers are ready for the snow.

7 hours ago

Thanksgiving travel tips...

Chris Sullivan

The mystery of the closed Kirkland overpass and Thanksgiving travel tips

Mike in Edmonds asked me about what he calls "the phantom" overpass of I-405 at NE 100th Street in Kirkland, plus Thanksgiving travel tips!

8 days ago

montlake 520 finish...

Chris Sullivan

Final phase of SR 520 plan in jeopardy

We're down to the final few months of construction, as the Montlake lid should be finished early in the second quarter of next year and the reversible lane from State Route 520 to the Interstate 5 express lanes should be done by June.

12 days ago

Ramp meter...

Chris Sullivan

Why the new I-90 ramp meters didn’t turn on Tuesday morning

I have been warning drivers for years that the Washington Department of Transportation (WSDOT) would be adding ramp meters to the I-90 connection to northbound I-5.

14 days ago

wsdot mountain snow...

Chris Sullivan

WSDOT claims it’s ready for mountain snow

Last year, WSDOT was down more than 120 people. WSDOT's Tina Werner said this year the agency is only down 25 positions.

19 days ago


Chris Sullivan

I-405 to close over the weekend for overpass demolition

For those that didn't know, going in and picking out a broken girder or two in the middle of the bridge is pretty complicated, expensive and time-consuming.

25 days ago

Demolition of cracking 520 project column to begin soon