CSX Virginia Avenue Tunnel Reconstruction

The scope of work occurred in two phases with no interruption to train operations. During the first phase, the project team demolished approximately 300 feet of the tunnel’s south wall and roof to accommodate the new south track. The team then constructed a secant pile wall system adjacent to the tunnel’s remaining section of the south wall. This wall acts as a part of the support of excavation system for the first phase of construction and is the dividing wall between the two new tunnels for more than half the tunnel’s length. The team also installed a drilled soldier pile and lagging support of excavation system offset south to the existing tunnel to allow excavation adjacent to the existing tunnel.

After demolition, the secant pile wall system, and support of excavation were complete, the team constructed a 4,100 foot cut and cover south tunnel, in a trench up to 50 feet deep, adjacent to the existing active tunnel. The team also constructed six temporary bridges over the tunnel excavation to ensure that north-south vehicular and pedestrian traffic are not affected.

During the second phase, the team demolished the remaining sections of the existing tunnel’s roof and south wall and constructed a new 4,100 foot cut and cover north tunnel. At the end of this phase, the team backfilled the trench, removed temporary bridges, and fully restored traffic to Virginia Avenue on a modified alignment that returned it closer to the historic L’Enfant Plan. 

Additionally, the team permanently relocated numerous water, sewer, electric, communications, and gas utilities. A new concrete arch bridge was also constructed over an existing masonry sewer tunnel to protect it under the new rail road tunnel. 

Clark/Parsons provided more than three years of support services under a Professional Services Agreement with CSX during NEPA environmental impact studies. During that period, the project team provided technical and preliminary design services to support CSX’s efforts to secure critical environmental approvals. 

C3M Power Systems, a subsidiary of Clark, was responsible for the complete installation of electrical, communications, signaling, and security systems conduit infrastructure. In addition, C3M installed electrical power distribution, lighting, and receptacles, controls for tunnel ventilation and drainage pumping systems, and security fiber optic cabling.