The City of Seattle is replacing the two-level highway viaduct that dominates the downtown shoreline with a two-level tunnel. A very large tunnel boring machine, named Bertha in honor of an early Seattle mayor, has been excavating the tunnel for several months. In December, Bertha encountered an unknown obstruction and came to a halt. Seattleites … Continue Reading
On January 6, 2011, the Washington State Department of Transportation (WSDOT) signed a contract with Seattle Tunnel Partners for the biggest piece of the SR 99 Viaduct replacement project, the 1.7 mile long tunnel carrying traffic from the south end of the Seattle waterfront to near the Seattle Center. This is a design-build contract with … Continue Reading
The $1 billion Brightwater wastewater treatment plant in north King County is experiencing delays. The attached video describes a problem with one of the large boring machines. The project, which includes several long tunnels and a central treatment plant, is divided up among several large contracts.… Continue Reading