While Lady Bird still has another four years of mining ahead, other major components of the tunnel system are taking shape. The Skanska-JayDee joint venture, in association with Parsons Brinckerhoff, has begun work on the 3,000-lf 19-ft dia First Street Tunnel, which will be constructed using an earth-pressure balance machine. The $157-million project is expected to be complete in 2016.

In early 2015, the Impregilo-Healy-Parsons design-build joint venture is expected to begin mining the $254-million 14,000-lf, 23-ft dia Anacostia River Tunnel using another Herrenknecht-built tunnel boring machine.

Also in 2015, DC Water expects to begin procurement for the 28,000-lf, 23-ft dia Northeast Boundary Tunnel, which will wrap around the District of Columbia’s northern neighborhoods to near Rock Creek.