Seattle Tunnel Boring Machine Underperforms After One Month

August 29, 2013

Bertha, the tunnel boring machine excavating Seattle’s Highway 99 tunnel, has traveled only 24 feet in its one month of operation, according to the Seattle Times. This puts the team two weeks behind schedule in digging the 1.7-mile tunnel, as the machine was originally estimated to move 6 feet per day at the beginning, and 35 feet per day under the downtown area.

The contractors on the project attribute the delays to large fiberglass strands stuck in the machine, as well as a labor dispute with the International Longshore and Warehouse Union.

Despite the delays, the team expects the project to be completed on schedule, with digging complete by fall 2014 and the tunnel to open at the end of 2015.

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