SR 411 Cowlitz River Bridge deck replacement work coming to Castle Rock

Travelers should plan ahead for year-long traffic delays

CASTLE ROCK – Just in time for its 60th birthday, the State Route 411 Cowlitz River Bridge, also known as A Street, in downtown Castle Rock is getting a much-needed facelift.

On Monday, Feb. 20, Washington State Department of Transportation’s contractor, Hamilton Construction Company, will begin work to replace the SR 411 Cowlitz River Bridge deck in Cowlitz County. The bridge spans the Cowlitz River and connects the east and west sides of Castle Rock.

"Keeping travelers and all users of the road safe and moving is our number one priority," said project engineer, Pedro Reyes. "Because of the age of the bridge, constructing a new bridge deck that meets current bridge standards for safety and accommodates all modes of travel will ensure that this vital connection remains in place and serves this community for many years to come."

Contractor crews will remove portions of the existing bridge in stages and construct a new, widened concrete bridge deck. The upgraded structure will allow for a new sidewalk on the north side of the bridge and will include pedestrian and bicycle friendly-traffic barriers. In conjunction with the bridge deck replacement, crews will add new bridge railings, strengthen the existing steel girders and install a new waterline for the City of Castle Rock that will run underneath the bridge deck.

What travelers can expect

Year-long, around-the-clock single lane closures and delays up to 15 minutes at a time during daytime and nighttime hours as well as a few weekends of total closures.

  • Full closures will not occur on a holiday, nor over a holiday weekend.
  • Ahead of full weekend closures, the contractor is required to provide a 10-day notice before they can fully close the roadway. Once those dates are known, notifications will be sent out publicly.
  • To ensure emergency services can gain access to nearby neighborhoods, all street parking is restricted along A Street and no stopping or waiting will be allowed in the 100 block of A Street.

WSDOT is working closely with the school district to reduce and minimize delays during peak school travel times. Travelers are encouraged to plan ahead and take alternate routes by traveling south along SR 411 to Lexington Bridge Drive or traveling north on SR 411 to SR 506.

Work on this $8 million dollar project is scheduled for completion in 2024.

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