There's nothing simple about replacing I-405 overpass in Renton, starting Nov. 1

By Tom Pearce 

If only repairing roads was as easy as 1, 2, 3. Unfortunately it's usually much more complicated. That's why on November 1-2-3 (and 4-5-6) we have some major closures planned on Interstate 405 in Renton to replace the Lind Avenue overpass, which was damaged in 2022. Those closures are:

• 11 p.m. Wednesday, Nov. 1, to 4:30 a.m. Thursday, Nov. 2: All lanes of southbound I-405 with a detour via the SR 167 interchange, Rainier Avenue and Grady Way. Closure is weather-dependent.
• 11 p.m. Thursday, Nov. 2, to 4:30 a.m. Friday, Nov. 3: All lanes of northbound I-405 with a detour via the I-405 and SR 167 collector/distributor. Closure is weather-dependent.
• 11 p.m. Friday, Nov. 3 to 4:30 a.m. Monday, Nov. 6: Southbound I-405 fully closed all weekend with a detour via Talbot Road and Grady Way. This closure will happen unless there are extreme conditions.

During overnight closures Nov. 1 and 2, drivers will need to use the I-405/SR 167 interchange as a detour.

The Nov. 1 and 2 closures will allow our contractor to restripe both directions of the freeway near the Lind Avenue overpass, just west of SR 167. Then, starting the night of Nov. 3, the crews will demolish the north span of the overpass above the I-405 southbound lanes.

The restriping is weather-dependent but not critical to the demolition work. However, the traffic shifts are necessary to rebuild the north span. The traffic shifts will create space for the crews installing the new girders and rebuilding the bridge. In late November/early December we'll have several more overnight I-405 southbound closures to install the new girders. The new Lind Avenue overpass should open in early 2024.

What happened

In June 2022, a backhoe being towed on a trailer struck the overpass, damaging five of the eight girders that support the structure. The damaged girders are not consecutive; there are undamaged girders between damaged ones.

When the backhoe on a trailer struck the Lind bridge, it broke concrete and severed steel cables that strengthen the concrete on five of the eight girders.

Considering the complexity of replacing basically every other girder, the age and condition of the overpass, replacing the north span of the overpass is the most cost-effective way to complete this work.

Bridge strikes happen many times a year across the state. Sometimes there is minor damage that can be repaired without major closures. Other times only one girder on one side of the overpass is damaged, so we can shift traffic away from that side of the bridge and keep the overpass open. We can usually remove the damaged girder and install the new one during overnight closures. With five damaged girders on the Lind Avenue overpass, that simply won't work.

What took so long?

A repair of this size requires several steps:

• We needed to determine the extent of the damage and what would be required to repair or replace the bridge.
• We needed to write a contract for the work and put it out for competitive bids.
• Once we selected a contractor, they needed to get their materials and order the girders.
• There is no Girders R Us. Every girder is a specific size, which means it needed to be custom-made. This can take several months.

Once all the pieces are in place, we expect the work to go relatively quickly, with the new overpass open in early 2024.

Who’s paying for this?

This is the most common question we hear. When state property is damaged, we work to recover costs from the responsible party, whether it’s a multi-million-dollar bridge or a small piece of guardrail. I can personally attest to this. Several years ago our son slid off a highway in eastern Washington in the winter and damaged a fence (he was fine). As the registered owners of the car, my wife and I got a bill a couple weeks later from WSDOT for about $240 (he paid the bill).

Getting around during the weekend closure

When we have weekend-long closures like this, or even lane reductions, you can take three steps to reduce traffic issues:

1. Plan ahead: use our mobile app and our Travel Center Map.
2. Consider alternate routes. In this case, think about using I-90 to I-5 in Seattle.
3. If you can, adjust your travel schedule to avoid peak hours, likely between 8 a.m. and 8 p.m.

When we close southbound I-405 for the weekend, drivers will need to use the Talbot Road exit and Grady Way to continue south.

Few things are as simple as 1-2-3. While the overnight closures will affect many people, we expect the biggest challenges will be during the weekend-long southbound closure. Following the steps above can help make it a little easier for you and others who need to travel through this area Nov. 3-6.