Contents tagged with Demolition
Crews will begin removing the Alaskan Way Viaduct after the new SR 99 tunnel opens to drivers. Tunnel opening is currently scheduled for early 2019. Removing the Alaskan Way Viaduct, which stretches along the waterfront from South King Street to Battery Street, is expected to take about six months. In 2011, crews demolished the southern mile of the viaduct, which accounted for nearly half the structure's total length.
WSDOT estimates there are more than 90,000 vehicles currently using the viaduct daily. Because this is an old road, there are no automatic traffic counts to pinpoint the number of vehicles that use the downtown ramps. A traffic count of three days in March 2018 (Tuesday – Thursday) showed that approximately 25,000 cars exited northbound at Seneca and Western Streets and approximately 31,000 cars entered the viaduct at Western Ave., Elliott Ave. and Columbia Street.
Routine safety inspections and maintenance keep the viaduct safe for public use. In 2008, crews strengthened four column footings where the viaduct had settled approximately five-and-a-half inches into the ground since the 2001 Nisqually earthquake. The column safety project limits settlement in this area of the viaduct and prevents further damage to the structure.
We also installed a system designed to close the viaduct automatically in the event of a moderate to severe earthquake in the greater Seattle area. The automated closure system consists of traffic gates at all viaduct access points controlled by an earthquake detection system. If the earthquake monitoring system detects significant ground movement, it will simultaneously lower all nine traffic gates and safely close the viaduct in two minutes.
In 2011, crews demolished nearly half of the vulnerable viaduct near Seattle’s port and stadiums. Drivers now use a construction bypass connected to new side-by-side bridges built to current safety standards.