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PALMER — A massive pileup in dense fog and frigid cold closed the Glenn Highway in both directions for several hours Thursday at the Knik River bridges in Mat-Su.
Alaska State Troopers said the chain-reaction collision involved 37 vehicles. The line of traffic skidded to a stop on the southbound bridge violently enough to injure more than a dozen people in cars, pickups, and at least two semis. Authorities and drivers described slick road surfaces with extremely limited visibility.
No life-threatening injuries were reported, said Ken Barkley, emergency services director with the Matanuska-Susitna Borough. Barkley said 13 people required medical transport from the scene — nine by borough ambulances and four by either Chugiak Volunteer Fire and Rescue or the Anchorage Fire Department. It wasn’t clear how many other people reported more minor injuries.
Troopers said the first report of a multivehicle collision on the southbound Glenn at the bridge came in at 10:35 a.m. A driver hit their brakes to avoid another vehicle in the same lane and began spinning, they said in an update posted Thursday afternoon.
Another vehicle in the same lane collided with that one, troopers said. “Nearly a dozen vehicles continued to collide with the initially involved vehicles. With the limited visibility, additional vehicles then began a chain reaction of rear-end collisions, in trying to avoid hitting one another.”
Additional collisions occurred even after first responders had reached the scene, causing a larger pileup and complicating access to the area, Barkley said.
Troopers initially closed the highway’s southbound lanes at the Parks Highway interchange around 11:30 a.m. but then diverted highway traffic in both directions to the Old Glenn Highway to allow emergency vehicles to access the area.
The northbound lanes of the highway opened just after 1 p.m. and the southbound lanes at 2:15 p.m., troopers said.
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Temperatures in the area were about minus 10 within a few hours of the first reports of collisions.
The bridge and an older bridge on the northbound highway are scheduled for overhauls as soon as this summer. Thousands use the bridges during the commute between Mat-Su and Anchorage. Especially in winter, drivers are wary of the icy spans given the ruts worn into the asphalt and abrupt lip at the transition from road surface to bridge.
[Repairs planned for worn Glenn Highway bridges over Knik River]
The northbound bridge was the scene of a large pileup in November 2016. More recently, icy conditions led to a seven-car collision on the same span on Christmas Day.
On Thursday morning, Anchorage resident Robert Borton was headed south on the highway when he said he called 911 to report a hazard on the bridge: a disabled pickup at the side of the left lane about 30 feet from the end of the span.
Borton said in a message that the “pea soup” fog was so thick he didn’t even see the black truck with its hood up until he was just 5 feet away.
“He had pulled off as far as he could,” Borton said.
He said he can’t be sure the truck triggered the pileup but the wreck began at that location within minutes, Borton said. He called 911 just before 10:40 a.m. after he and three others nearly hit the pickup.
“Like I said within minutes of my call the accident was getting reported on Facebook,” he said.
Troopers spokesman Tim DeSpain said the only information he had about the start of the pileup was that a vehicle going at a reduced speed or braking caused the chain reaction.
Troopers ask anyone involved in the collisions who has not already been interviewed by police or troopers to call 907-352-5401 and to reference the case number AK24007954.
Zaz Hollander reported from Palmer and Tess Williams from Anchorage.