It’s okay to stare – WSDOT is preparing to make tunneling history

Usually, it’s not polite to stare, but in this case it’s history in the making, so it’s encouraged. Crews are preparing right now for the world’s largest-diameter tunnel-boring machine to arrive in 2013. The Washington State Department of Transportation is inviting the public to stare in amazement at the massive work zone for the State Route 99 tunnel project.

Join project leaders this week on a mile-long, round-trip walking tour along the bicycle/pedestrian path adjacent to the construction site. Watch crews dig the launch pit for the 300-foot-long tunnel-boring machine and hear explanations of the equipment being used to do the work.

Although the five-story-tall tunneling machine won’t take the stage until next year, its supporting cast – including a fleet of massive cranes, drill rigs and excavators at work to the west of CenturyLink Field – are impressive in their own right. In addition to digging the 80-foot-deep pit where the machine will begin its northward journey, crews are building a new overpass and putting the finishing touches on a new section of SR 99 to replace the south end of the Alaskan Way Viaduct.

The tour will begin at Milepost 31, the Alaskan Way Viaduct Replacement Program’s information center in Pioneer Square. This center houses interactive exhibits, a model of the SR 99 tunnel-boring machine and the latest project information.

Walking tour details(pdf 276 kb)

6 p.m., Thursday, Sept. 6

Meet at Milepost 31, 211 First Ave. S., Seattle

For those who can’t attend, a new self-guided tour is available. Displays have been installed along the bicycle/pedestrian path to describe construction activities, machinery at work and the area’s history. Access to the path’s north entrance is available at South King Street and Alaskan Way South, a few blocks south of Colman Dock, or the south entrance is at South Atlantic Street and Alaskan Way South, west of Safeco Field. Maps are available at Milepost 31. Construction cameras and Flickr photos also provide a regularly updated view of the work zone.

Learn more about the Alaskan Way Viaduct Replacement Program at www.alaskanwayviaduct.org and Milepost 31, which is open 11 a.m. to 5 p.m. Tuesdays through Saturdays and is open late during Pioneer Square’s First Thursday Art Walk. Admission to Milepost 31 is free.