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?
Viaduct, City Council share that sinking feeling
Why Seattle’s Huge Tunnel-Boring Machine Is Still Stuck
Bertha inspections held after settlement detected
New delay in Bertha rescue as engineers study sinking soil
Is Bertha’s pit affecting Pioneer Square buildings?
McGinn-era tunnel study proving true: Bertha project was ‘high risk,’ geology a challenge
Poll: Seattle Business Community Stands by Tunnel Project
Tunnel repair rattles Seattle residents
Guest Editorial: We Need to Stop Trying to Rescue This Tunnel Project and Consider Our Options