Old Trolley Bridge on Clackamas River slowly collapsing

GLADSTONE, Ore. - The Old Trolley Bridge on the Clackamas River is slowly collapsing.

The Clackamas County Sheriff's Office says boaters should avoid passing under the bridge, which is downriver from High Rocks Park.

The bridge is part of an abandoned trolley line that connected Oregon City and Portland in the early 20th century.

A construction crew working near the bridge noticed that one of the bridge supports was tilting downriver Thursday morning. Lt. Robert Wurpes with the Clackamas County Sheriff's Office said the bridge piling moved about four feet in one hour.

"Clackamas County Engineers who were called in to assess the bridge advised the shift is significant and alarming. There is a valid concern about the overall stability of the bridge," Wurpes said in a news release.

The bridge is owned by Union Pacific. They are aware that the bridge is unstable and their engineers are evaluating the situation, Wurpes said.