Kiewit-Traylor Bros Joint Venture has completed more than 50% of shaft excavation on the Ellicott City North Tunnel Project in Maryland.
The 49m-deep shafts will provide the TBM launch and retrieval sites for the water project.
A 91.5m-long Robbins main beam TBM named Rocky is currently undergoing a full overhaul and is scheduled to arrive in Ellicott City in the autumn. Rocky will excavate a 1.768km-long, 5.5m-diameter tunnel through solid granite, approximately 46m below the surface.
Once complete, the North Tunnel will be capable of diverting 26,000 gallons of water per second to the Patapsco River, helping protect Ellicott City’s Main Street from flooding by channelling water underground.
The Extended North Tunnel Project is the single largest public works project in Howard County’s history and is the focal point of the Safe and Sound plan. The County broke ground on the project in June last year. The project is due to be completed in autumn 2027.
