Dense Soil Conditions Delay Bridge Opening

Tue December 17, 2019 - West Edition #26

(WSDOT photo)
(WSDOT photo)

Since mid-June, the Washington State Department of Transportation closed a portion of State Route 506 near Vader to replace the aging and failing Lacamas Creek Bridge in Lewis County.

While drilling foundations for the replacement structure, WSDOT's contractors, Farline Bridge Inc., discovered dense soil conditions, which will delay the reopening of the highway. Construction was originally scheduled to be done in 2019, and redesign work needed to complete the job will delay the project completion until next year.

"The soils about 60 feet below the original bridge shaft locations are denser than we originally determined during design investigation," said WSDOT Project Engineer Colin Newell. "As a result, the contractor was not able to drive the steel shafts for the structure's foundation to the required depth. This required a redesign of the shafts and the need to procure new reinforcing steel for them."

When the newly designed reinforcing steel arrives, crews will begin installing them, digging some 80 ft. down into the earth, then filling the shafts with concrete. Crews plan to work through the winter, as weather allows.