Another Anchorage footbridge collapses, this one on the Campbell Creek Trail

A wooden footbridge on Anchorage's Campbell Creek Trail collapsed Tuesday morning after a city employee made the mistake of trying to drive heavy snow-clearing equipment across it.

The bridge is on the west side of the Seward Highway and just north of International Airport Road. A new detour around the bridge takes trail users up to the Seward Highway overpass at Tudor Road, about 10 blocks out of their way.

John Rodda, the city parks director, said the employee was finishing clearing up some of the trails at about 8 a.m. Tuesday when, "unfortunately, he elected to start across the bridge.

"And he went through it," Rodda said.

No one was injured, Rodda said. He also said the equipment, which resembles a tractor and weighed roughly 7,800 pounds, fell through the bridge decking to the creekbed below but apparently wasn't damaged.

He said he had not yet spoken directly with the employee and didn't know exactly what happened or the cost of a replacement bridge.

"I think he didn't realize until he got close," Rodda said. "He was in a little bit of shock that it actually happened."

The city banned motorized equipment on greenbelt bridges after the 2014 collapse of the footbridge at the north end of Westchester Lagoon.

In 2014, a Ford F-550 truck drove onto the Westchester Lagoon bridge, pulling a wood chipper. The bridge was decaying from years of water seeping in through openings around bolts.

Using $1.5 million in bond money, the Westchester bridge and several other bridges along the Tony Knowles Coastal Trail were replaced with steel ones.

But there's no plan yet for replacing other aging footbridges along Anchorage's trail system that may also be structurally vulnerable — more than 30 bridges in all.

[Footbridge collapse highlighted Anchorage's deteriorating greenbelt infrastructure]

Engineering students at the University of Alaska Anchorage have been surveying the city's network of bridges as a class assignment.

Rodda said the results of that report will help the city decide which bridges to replace first, and how to pay for it.

In the short term, Rodda said, engineers are examining the collapsed bridge and will come up with a temporary replacement. He said the fix should be in place by mid-May.

He also said an upcoming seasonal orientation with city staff will emphasize the ban on taking motorized equipment over greenbelt bridges.

"We don't want this to happen," Rodda said.