There is evidence that the pumping of groundwater during the digging of a pit needed to repair Big Bertha, the tunnel boring machine attempting to dig the SR-99 Alaskan Way Viaduct replacement tunnel in Seattle, is causing subsidence of the earth and is having an impact on buildings in the area. Over the past week, there have been many, many articles covering aspects of the problems being faced by Seattle, the State of Washington, and the contractors (Seattle Tunnel Partners). What is happening, why it is happening and the what does this mean for the future of the project?
Big Bertha – Seattle Tunnel
In Seattle, a Sinking Feeling About a Troubled Tunnel