Bertha Stuck Again: Sinkhole Prompts Suspension of Highway 99 Tunnel Project

Mike Lindblom reports: "Gov. Jay Inslee ordered Highway 99 tunnel contractors Thursday to suspend drilling the deep-bore tunnel along the Seattle waterfront, until a sinkhole that formed this week is fully investigated."

Though the sinkhole has been filled, ground above the Bertha tunnel-boring machine is continuing to sink, according to the Washington State Department of Transportation (WSDOT). "But in calling for the work to stop, the governor aired the worry shared by many citizens — that if Seattle Tunnel Partners (STP) continues to dig too much soil as Bertha proceeds north, the viaduct and downtown buildings could be threatened," according to Lindblom.

The article includes details about how the steps the state is taking to inspect the project while its suspended. The state's actions reflect a new twist in its relationship with contractors on the project. More also can be found on the document announcing the suspension of the project.