Concrete begins to flow at West Seattle Bridge repair job

Repair crews at the West Seattle Bridge received fresh concrete early Tuesday, despite a 4-month-old truckers’ strike that’s disrupted regional construction projects.

Fresh slurry flowed overnight from a Cadman company mixer, down a chute, and into blue wheelbarrows, as captured in a photo distributed by the Seattle Department of Transportation.

Mayor Bruce Harrell claimed partial credit for the delivery, while thanking both the International Brotherhood of Teamsters Local 174 and the Cadman company, which worked out a temporary deal to deliver the concrete. “This collaborative effort is rooted in a desire to support our communities and advance the greater public good – and for that we should all be immensely grateful,” Harrell’s statement said.

Tuesday morning’s batch was aimed toward hardening some newly repaired expansion joints, where built-in gaps between roadway decks accommodate the bridge’s normal thermal movement.

SDOT and contractor Kraemer North America have yet to attack the more complex job of building concrete anchors within the hollow girders, where dozens of new steel cables will be installed, each exerting 1 million pounds of lateral force on those future anchors. That phase requires premium “self-consolidating” concrete, which flows and hardens without leaving tiny air pockets that can trigger future cracks.

The anchor mixture was tested by a Seattle Public Utilities materials lab, and approved last week, according to City Councilmember Lisa Herbold of West Seattle. Approximately 30 truckloads will be required.

“We’re hoping to get the specialized concrete within the next few weeks,” said SDOT spokesperson Mariam Ali.

As of Tuesday afternoon, officials haven’t identified a date for anchor-building, nor to reopen the seven-lane crossing. Kraemer’s original schedule targeted a June 30 completion, followed by SDOT heavy-load testing in early July. But that was predicated on concrete deliveries by Feb. 20. Delays are likely.

The highrise box-girder bridge, completed in 1984, has been barricaded since March 23, 2020, when SDOT structures director Matt Donahue diagnosed runaway shear cracks. Many of the 100,000 daily drivers and 20,000 transit passengers who normally use the bridge are working from home, curtailing leisure trips, or detouring as far as 6 miles, via the First Avenue South bridge.

The Teamsters announced in mid-March that 40 union drivers offered to resume work at Cadman, while still continuing the broader strike, in which 330 members walked out Dec. 3 as negotiations broke down over wages and other issues.