Portland released dramatic photos Friday showing the scale of damage that occurred last weekend when a Union Pacific train derailed and smashed into multiple Swan Island bridge support columns.

Nearly a week after the two locomotives and three tank cars carrying liquified petroleum gas derailed and crashed into the bridge, Portland engineers are still uncertain how long repairs will take.

“We weren’t kidding when we said this would take some time,” said Dylan Rivera, a transportation bureau spokesman.

The city still says it could still be “several months” before crews are able to reopen all lanes on the bridge on North Going Street, the major connection between the rest of the city and the Swan Island Industrial Area.

Monday morning’s commute was a snarl, but employers said they would adjust people’s schedule if possible to deal with the limited travel lanes to the industrial area.

Rivera said the city has heard from businesses that delays were “significant enough to really cause significant pain."

Union Pacific will halt trains on its line adjacent to the most severely damaged bridge column this weekend, Rivera said. That will give city engineers and contractors the opportunity to dig into the earth to examine the concrete support footings and pilings to see whether those structures were also damaged.

But the city does plan to reopen a third lane on Going Street “sometime the week of Sept. 16,” though the precise date is not yet clear.

14 Swan Island traffic jam on first Monday commute following train derailment

This week, traffic was limited to two lanes across the bridge, one in each direction. Next week, the second westbound lane will be restored.

City crews repaired a section of the bridge’s deck this week, removing damaged concrete from the 89-year-old bridge span.

Rivera noted this week that the bridge is actually three separate structures. The middle bridge, which suffered the most damage in the derailment, was built in 1930. The other bridges on either side were built in 1976.

In 2010, the city seismically upgraded the bridges and connected them for “lateral support,” Rivera said.

“We think the reinforcement we did intending to make it more resilient in the event of an earthquake may have also made it more resilient during last weekend’s train crash,” he said.

More than 35,000 vehicles use the bridge every day.

The city and Union Pacific officials are asking employees traveling to the job hub on the island to stay off North River Street, a private road through the railroad’s Albina Yard. That route was briefly posted as a detour in the wake of the derailment, but it is not equipped to handle large scale traffic, and some drivers “got lost” on the property this week, Rivera said.

It’s still unclear what the city will do with the damaged support columns. Rivera said options could include building around them, replacing them altogether, or otherwise shoring up the damaged columns.

Update: A previous version of this story referred to the damaged structures as beams. It’s been clarified to reflect they were support columns.

-- Andrew Theen

atheen@oregonian.com

503-294-4026

@andrewtheen

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