Dorchester Tunnel

Client: Massachusetts Water Authority
Location: Boston, MA
Start Date: August 2007
End Date: October 2009
Contract Value: $146 million

Balfour Beatty Infrastructure, Inc. began work in August 2007 on the Dorchester Tunnel in Boston, a $146 million job for the Massachusetts Water Authority. The three-year project was a joint venture with M. L. Shank, Co.

The work involved cutting an 11,000-foot tunnel to receive storm water runoff that empties into a pump station. The tunnel is 17 feet in diameter and is constructed of a series of four-foot rings that create a watertight internal surface. The top of the tunnel lies 30 feet beneath the street.

A sophisticated cutting machine that tunnels through various materials -- clay, sand, organic material, gravel -- progressed at a rate of 48 feet per day during the project’s two nine-hour daily shifts.
 
   

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