Pierce County bridge closed indefinitely to pedestrians, traffic after deemed unsafe

The Interlaaken Bridge over Lake Steilacoom will be closed indefinitely to car and pedestrian traffic after structural engineers determined rapid deterioration of wood beams on the bridge have compromised its safety.

The bridge connects Lake Steilacoom Drive Southwest to Mt. Tacoma Drive Southwest toward Lakewood Town Center through Interlaaken Drive Southwest. There are road closure signage posted at Waverly Drive and before the turn onto Interlaaken Drive Southwest, said Brynn Grimley, a city spokesperson.

The bridge was built in the early 1920s and was retrofitted in the 1950s, Grimley said. Lakewood has done regular maitenance of the bridge, including beam and cap replacements over the years, most recently in 2012, she said.

On Friday morning, Lakewood city engineers met with consultants and the Pierce County Engineer’s Office and concluded the bridge would be closed to all traffic while the city reviews its options for how to proceed, according to a press release.

“Engineers are also assessing which crossings under the bridge can remain open to water traffic. It is anticipated that a number of these passages under the bridge will be closed for safety reasons,” the city said.

Last week the city reduced traffic to one lane on the bridge to limit the weight on it. That guidance followed a previous weight restriction earlier this year in response to the compromised wood beams.

Despite the weight restriction, some vehicles over the allowed weight crossed the bridge, so the indefinite closure “was made from an abundance of caution for public safety,” according to the city.

Inspections of the Interlaaken Bridge were conducted in 2019, 2021 and 2023, per the standard inspection schedule. An inspection done last week discovered the rate of deterioration “had progressed quickly from the last inspection” and “are now unsafe to handle the load capacity of the bridge,” the city said.

The public is asked to obey posted signage, and those found on the bridge could be subject to police enforcement action.