top of page


Tysons Corner, VA


Design Completed 2007, Full PE Drawing to Build Tysons Tunnel


McLean Chamber of Commerce




Urban Designer - Architect - Architect of Record

The tunnel alternative for Tysons was proposed for a 3.38-mile-long segment of Dulles Rail, the portion of the Project that runs along Route 123 and Route 7 through the Tysons Corner area. The tunnel alternative would replace an elevated alternative for Metrorail while maintaining the same alignment and the same four stations and locations underground. The benefit of the tunnel lies in a transportation system and station connections located underground which provides mobility and access into and out of the Tysons Corner area, while keeping the ground surface free for planning and redevelopment to meet the future needs and desires of the community.

The station entrances visibly accentuate Metro locations on the ground surface with a steel and glass canopy over the escalators and stairs. The glass allows light to reach down into the entry areas below grade. Each station has two access points, one on either side of the street, which are connected underground through a pedestrian walkway. In this fashion, patrons are taken out of the weather as soon as they step under the canopy or into an elevator. The station entrances and mezzanines are constructed underground, outside the tunnel, and are built similar to any building basement, before the building above. These entrances have the potential to be designed in future “air-rights” construction (buildings over other uses) which will help create the urban forms necessary to define a walkable community. With the glass canopy daylight reaches the lowest platform level and when exiting the station provides orientation and a clear path to follow up to the surface. The vaulted entry space is provided with indirect lighting highlighting the structural ribs that support the execution.

What sets this metro tunnel apart from the “traditional” metro tunnels constructed in the DC area is the use of a single, large-diameter boring machine to mine an opening large enough to accommodate two rail lines, stacked on top of each other, along with space for platforms at the stations.

Tysons Tunnel gained huge approval from the residents of the area. 17,000 people signed a petition to get the governor to approve the plan. The rallying cry became "It's not over until it's under". Unfortunately, the politicians didn't have the willpower to overturn the contractors who would make more money if it was aerial - even though the price was the same for either version. The tunnel cost was in the Big Bore Tunnel Machine which only took about 6 people to operate, preventing the contractors from making money on all the other people employed on their stick-built aerial.

bottom of page