The Alaskan Way Viaduct: How Seattle chose the Bertha tunnel alternative

In April of 2017, Bertha, the massive tunnel-boring machine successfully completed digging a nearly 2 mile deep-bore tunnel under Seattle. The tunnel will carry traffic from the Alaskan Way Viaduct, which had been damaged and deemed seismically unsafe after an earthquake. The tunnel will be much less intrusive than the wall-like Viaduct structure, which cuts […]

source https://seattlepalate.com/tech/the-alaskan-way-viaduct-how-seattle-chose-the-bertha-tunnel-alternative/