An old abandoned bridge over the Clackamas River appears to be leaning toward collapse.
The Old Trolley Bridge once connected Oregon City to Portland in the early 20th century. Now, the bridge is badly tilting downriver.
Construction crews working near the bridge first noticed the problem Thursday morning. Within the span of a few hours, the top of the bridge piling had moved four feet toward Oregon City.
Deputies are strongly advising boaters to avoid passing under the bridge downstream from High Rocks in case it collapses.
There are boat launches above the area at Riverside Park and below the area at Meldrum Bar Park.
The bridge is currently owned by Union Pacific. Local police and fire agencies said they are working with the company on a plan to handle the situation.
Firefighters said the river is running extremely high and fast right now, but this is still the first time they've seen such a significant structural shift involving the bridge.
The bridge is an abandoned remnant of a trolley line between Oregon City and Portland operated by the now-defunct Portland Traction Company, according to the Clackamas County Sheriff's Office.
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