Ship canal Water Quality Project – Seattle, WA
In the bustling seaport city of Seattle, Wash., work is steadily advancing on the Ship Canal Water Quality Project, which aims to prevent an average of 75 million gallons of polluted stormwater and sewage from entering Seattle’s waterways each year.
We are working on the 210-ft-deep, 87-ft-wide drop shaft in Ballard, where the TBM will be launched in 2021. To support the excavation, we are installing an 87-ft-dia diaphragm wall to a depth of 210 ft to cut off the groundwater. The 4-ft-thick shaft ring consists of 18 vertical panels, most of which are reinforced with steel rebar. Fiberglass reinforcement is being employed at the tunnel eye where the TBM will break through to commence its tunnel drive.