A tanker truck crash on the Alaskan Way Viaduct spilled thousands of gallons of gasoline and set off a massive fire in downtown Seattle 50 years ago today, according to historylink.org.
In the early hours of December 4, 1975, a Union Oil tanker truck lost control while heading south on the viaduct near South Washington Street, across from Pier 48.
The rig jackknifed, causing its trailer — filled with 3,700 gallons of gasoline — to separate, overturn, and rupture.
The gasoline immediately ignited, sending flames towering above the roadway and spilling burning fuel 40 feet down onto the street, a nearby freight train, and several parked cars.
Although no one was killed, the fire caused widespread damage throughout the south end of downtown and exposed long-standing concerns about hazards involving fuel transport on the elevated highway.
The crash happened just after 1 a.m.
Driver Richard Leroy Baker, 40, had left the Union Oil tank farm north of Broad Street with a full load of gasoline bound for local service stations.
Investigators later said he was traveling about 52 mph on a wet, “traffic-polished” surface through a section of viaduct that curves sharply to the right.
The posted limit was 45 mph.
When Baker hit the left guardrail, the trailer detached and slammed into a concrete support column.
Flames swept across both levels of the viaduct as burning gasoline poured downward onto a Burlington Northern freight train and nearby vehicles.
Four boxcars were heavily damaged.
A brakeman on the train narrowly avoided being struck by a set of trailer wheels that fell from the elevated roadway.
Baker managed to drive the front tanker — containing another 4,800 gallons of gasoline — off the viaduct and away from the flames.
Crews from Fire Station No. 5, located on the waterfront, reached the scene within minutes and began attacking the fire from below.
Additional firefighters responded from the Columbia Street on-ramp and First Avenue South off-ramp.
Roughly 75 firefighters worked to stop the flames and brought the fire under control within 45 minutes.
The blaze damaged or destroyed at least 30 cars parked beneath the viaduct. Seventeen were total losses.
Nearby buildings also caught fire.
Flames reached the Alaska Hotel at 75 South Main Street, which housed Shelly’s Leg, known as Seattle’s first gay discotheque.
About 150 people were inside when windows began breaking from the heat.
Security guards rushed patrons out a rear exit, and no injuries were reported.
Two Seattle police officers had been parked underneath the viaduct near the club when the gasoline ignited, but both were uninjured.
The fire also incinerated six major electrical cables attached to the underside of the roadway, knocking out power to several prominent buildings.
The blackout affected the YMCA, the Colman Building, the Seattle Municipal Building, and the Public Safety Building, which housed both the police department and the city’s emergency call center.
The 911 system remained online due to backup generators.
Repairing the damage, however, became complicated.
Local 77 of the Electrical Workers Union was on strike, and its emergency committee declined to provide crews because the outage “did not endanger life,” according to reporting at the time.
City Light supervisors ultimately repaired the lines and restored power the following day.
Both levels of the Alaskan Way Viaduct were shut down after the crash while engineers assessed the structure.
Though the viaduct was deemed safe for use, crews removed loose concrete from the underside of the top deck before reopening the roadway for the morning commute.
Structural repairs to damaged beams were completed later with epoxy.
The event instantly renewed decades of debate over allowing hazardous cargo on the elevated highway.
When the viaduct opened in 1952, all trucks carrying dangerous materials were prohibited from using the structure or the Battery Street Tunnel.
Fire officials argued at the time that a single tank-truck fire could send burning liquids cascading onto streets, buildings, and people below — a warning many felt was realized in the 1975 crash.
Over the years, restrictions loosened under pressure from petroleum and transportation interests.
Heating oil shipments were approved in 1961, and by 1967 flammable liquids were permitted except during weekday rush hours.
Before agreeing, the Fire Department required the installation of water standpipes at one-block intervals along the entire viaduct.
After the 1975 fire, Seattle Fire Chief Frank Hanson said the accident “had the potential of being as disastrous as any in the city’s history from the standpoint of injuries.”
He agreed to meet with federal safety agencies to discuss ways to reduce hazards but added, “We’ve obviously got a hell of a problem.”
The National Transportation Safety Board sent two investigators from Washington, D.C., who concluded the crash was caused by driver error.
Contributing factors included excessive speed, a slick roadway, and the trailer’s lack of antilock brakes.
The property damage estimate was about $750,000.
City leaders ultimately decided that reinstating a full ban on transporting flammable liquids on the viaduct was not practical.
They argued that routing trucks along surface streets near the waterfront or through industrial areas posed equal risks.
The Alaskan Way viaduct was finally demolished in February 2019.
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