Traffic is moving again on southbound Interstate 5 near Mercer Street in Seattle on Thursday evening, after a welding supply delivery truck caught fire and exploded several times.
Initial reports said the truck was carrying liquid oxygen. Seattle Fire has since clarified the truck was carrying oxygen, acetylene and propane, plus an argon cylinder.
Plumes of smoke could be seen billowing in the air and from miles away, as the fiery scene initially shut down both sides of the freeway before 2 p.m.
The fire caused several explosions that could be heard by those nearby.
At one point, one of the tanks that exploded on the truck fell down the freeway’s bridge side and landed at a construction site, causing a small fire.
Seattle firefighters called to the scene had limited access to water, as hydrants were far away from the freeway. They also requested help from the Seattle Department of Transportation and Boeing, which provided an additional foam truck to help put out the flames due to the hazardous situation.
By 2:15 p.m. crews had foam on the fire and at 2:23 p.m., an alert system from the city notified residents at Lakeview Boulevard East near southbound I-5 to close their windows and doors to avoid smoke exposure.
The Washington State Department of Transportation alerted drivers that they should expect long delays on southbound I-5 as all lanes were closed, including the Mercer Street and southbound Boyleston ramps.
Chopper 7 flew over the scene of the fire and observed traffic which was backed up all the way to Northgate.
Washinton State Patrol said several vehicles overheated or ran out of gas while traffic was backed up.
After 3:45 p.m., the southbound express lanes on I-5 were reopened.
Before 7:30 p.m., the Seattle Department of Transportation tweeted that southbound I-5 was clear and all lanes were reopened. However, bridge inspectors had to make sure the bridge was safe before drivers could use the road again
— AlertSeattle (@AlertSeattle) July 29, 2022
While the explosion left behind a charred truck, the driver was able to evacuate the scene before the explosions occurred.
The fire and explosions caused damage to some signs on the freeway and had to be removed.
Here are some visuals on the damage to the vehicle and signage on southbound I-5 just north of Mercer Street. Our crews removed two signs due to the fire. pic.twitter.com/FCbmHsYCHc
— WSDOT Traffic (@wsdot_traffic) July 29, 2022