Bridge inspectors confirmed the Columbian Way overpass is safe to drive, said a spokesman for the Washington State Department of Transportation. About 5,300 vehicles a day use it.
The Columbian Way overpass of Interstate 5 sustained minor damage from the spectacular charter-bus fire Jan. 25 that forced the Stanford University track team to run for the roadside.
Intense heat melted a steel maintenance hatch and small amounts of concrete flaked away, leaving three rods of steel rebar exposed. Black char marks remain on the bottom and sides of the overpass Damage is limited to a single span in the southbound offramp that curves toward Beacon Hill — directly over the right northbound lane of mainline I-5.
Bridge inspectors confirmed the ramp is safe to drive, said Bart Treece, spokesman for the Washington State Department of Transportation (WSDOT). About 5,300 vehicles a day use the overpass.
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The blaze caused a 10-by-15-foot area of “light scaling/spalling from the fire,” according to the state’s bridge inspection report. Spalling refers to crumbling of surface fragments.
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The state also found minor delamination, in which a crevice formed a few inches under the surface. If not repaired, pieces could fall onto passing vehicles, or rebar might corrode. The steel hatch sagged 12 inches.
Word of the damage came Feb. 5 from Mike Worden, who is Seattle Mayor Jenny Durkan’s new director of Citywide Mobility Operations Coordination. Worden, a former Air Force general, praised the quick response to the fire in a briefing to the City Council.
“It was a hot fire. When they arrived they got it out in 20 minutes, which was amazing,” he said. “They ran a hose 2,000 feet down to Airport Way to get to a fire hydrant, to sustain fighting the spalling that was going on underneath the hot bus, and on the overpass, because it might be a structural risk.”
Stanford’s track team was on its way to a meet at the University of Washington when the bus caught fire.
A WSDOT engineer examined the overpass immediately after the fire was extinguished, and traffic resumed in about an hour.
State workers also inspected the bridge and removed the loose concrete the night of the fire, Treece said.
A right-lane closure may be needed this spring to paint the exposed rebar with rust inhibitor, and fasten a permanent screen across the hatch to keep birds out, Treece said Wednesday.
“There’s not an immediate need here,” he said.
Most important, the 32 people in the bus escaped unharmed.