It appears likely that West Seattle motorists will marinate in detour traffic for extra days or weeks this summer because a strike by concrete truck drivers continued past Sunday. The city said it needed a fresh supply of concrete by Sunday to keep high-rise bridge repairs on schedule.

Contractors don’t need much material, but they need it now if they hope to finish the $45 million strengthening job in June.

“We are just 245 cubic yards — fewer than 30 truckloads — away from the finish line,” observed City Councilmember Lisa Herbold of West Seattle, in an update to constituents.

It’s not the volume but the timing that makes the city’s bridge-strengthening project vulnerable.

The Seattle Department of Transportation hopes to complete repairs by the end of June, then open all seven lanes after about 15 days of load testing.

The mammoth box-girder bridge, built in 1984, has been barricaded since March 23, 2020, when city structures director Matt Donahue observed runaway shear cracks growing two feet in two weeks. It served about 100,000 vehicles and 20,000 transit riders a day pre-pandemic. Once reinforced, the three-span crossing is supposed to last another 40 years.

Repair crews from Kraemer North America need pumped-in concrete to build large blocks on the girder floors, then allow 28 days for curing. The blocks will serve as anchors for 91 tons of steel cable, to be stretched lengthwise through the cracked central span and the aging sidespans that show signs of fatigue. Those cables are to be tightened, which compresses and strengthens the concrete girders, a method known as post-tensioning.

Mayor Bruce Harrell announced the Feb. 20 date to start pumping new West Seattle Bridge concrete earlier this month.

Heather Marx, the city’s West Seattle Bridge program director, said in an interview last week, “Once we hit that time, we will start to see delays in the schedule,” and contractors still need a few days to arrange deliveries, if the strike ends soon.

The contract provides flexibility for repair teams, already working six 10-hour days per week, “to at least come close to that original contract. But the longer the strike goes on, the harder that gets,” she said.

SDOT says all its extra days in the schedule, known as float, are used up. Workers on suspended platforms will move forward with wrapping the outside in carbon fiber and fill cracks with epoxy.

“June 30 is still a goal. It will be tight,” said Adam Dour, project manager for Kraemer North America, the prime contractor, who couldn’t predict how long the concrete delivery impasse will last. Meanwhile, workers are building forms and rebar frames, to be ready the moment concrete arrives.

Heavy construction projects across the Seattle area have faced potential delays since 330 members of Teamsters Local 174 went on strike Dec. 3. The strike affects Sound Transit, which has laid off some workers building light-rail extensions that need concrete.

To save time, Dour said, Kraemer is negotiating with concrete suppliers to deliver several loads to the bridge simultaneously, and to arrange deliveries very early in the morning and late at night, when there’s less competition for mixer drivers.

Kraemer will install 40 concrete blocks for anchoring 46 miles of steel cables, along with concrete frames guiding the cable positions and angles, like the grooved bars that hold guitar strings in place.

Marx said one possible advantage for Kraemer is that it will custom-order “super plasticizing, self-consolidating concrete,” so the high-rise bridge won’t have to compete with other projects needing standard concrete.

The special concrete will coalesce without any need to plunge a power vibrator into the slurry, a task workers at the 2007 Tacoma Narrows Bridge performed hundreds of times while forming its 510-foot-high towers. The new West Seattle Bridge concrete must flow into tight spaces and angles where crews can’t vibrate the slurry, Dour said. Tightly settled concrete avoids water or air pockets, which can eventually generate cracks.

More concrete will be needed this spring for repaving, expansion joints and sign foundations.

King County Executive Dow Constantine this month proposed recruiting a company to become an exclusive supplier, using union labor, with hopes to prevent delays at the Washington State Convention Center expansion, King County Metro bus lanes, and other public works.

The top rate for mixer drivers is about $37 per hour, according to the Teamsters, who say raises have trailed those of construction trades unions. On taxpayer-funded jobs, the prevailing wage for a ready-mix driver on a King County project starting today is listed at $69.95 an hour including benefits, according to the Washington State Department of Labor & Industries.

To be sure, West Seattle frustrations over a two-plus-year bridge closure can’t be blamed on the concrete trucking dispute.

After the runaway cracks were stabilized in autumn 2020, by Kraemer under an emergency contract, SDOT conducted bidding before it awarded Kraemer the full repair contract in May 2021 — rather than save possibly six months by making a sole-source award to Kraemer again.

Marx said a competitive bid process was needed to qualify for federal grants, promote fairness and ensure the lowest possible price.

“That’s $37.7 million that the city of Seattle and the citizens of Seattle don’t have to cover. In order to get that federal money, we had to have a competitive process,” she said. SDOT’s total Reconnect West Seattle program costs around $175 million, including neighborhood safety, signal and pavement projects, repairs to the two-lane swing bridge below, engineering, and the 2020 emergency stabilization.

Cynical thinking about the bridge is so pervasive in West Seattle that people barely react when Deb Barker, a member of the city’s citizen advisory panel, talks to neighbors about the concrete strike impact.

“What I’m hearing is cynicism and a resignation,” Barker said. “Yeah, there will be something else.”

Material from The Seattle Times archives was included in this report.

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