Oversize trucks carrying five, 155-foot-long steel bridge girders destined for the timber bridge replacement project will close the northbound State Route 99 off-ramp to East Marginal Way South Thursday night and Friday morning.

Northbound freight haulers and drivers heading to the Port of Seattle can reach their destination by following a signed detour on First Avenue South. The next northbound SR 99 off-ramp north of East Marginal Way South is Seneca Street.

Closure details

• 9 p.m. Thursday, May 23 until 5 a.m. Friday, May 24 – The northbound SR 99 off-ramp to East Marginal Way South will be closed.
• Detour: First Avenue South to South Hanford Street to East Marginal Way South.

The old timber supported section of Highway 99 located just south of the West Seattle Bridge was built as a temporary bridge over the railroad tracks in 1956. Replacement work to rebuild one half of the bridge at a time began in February 2013 and wraps up in June 2014.

Bridge girders form the backbone of the bridge by supporting the deck and roadway lengthwise from underneath. Each of the 73-ton girders is 3 feet wide, nearly 5 feet tall and 155 feet long.

Construction progress information, including a project map and photos are available here or go to www.wsdot.wa.gov and search “SR 99 timber bridge.”

Contact:  Broch Bender, WSDOT communications, 206-440-4699 (Shoreline)