Tysons Tunnel Alternative

Location

Tysons, VA

Status

Design Completed 2007

Client

Washington Metropolitan Area Transit Authority

Cost

KGP was the architectural component of a joint venture team with Dr. Sauer and ARUP. They designed the stations and station entrances for the Tysons section of the planned 23-mile transit system extension in the rapidly growing Dulles Corridor. This team produced the Preliminary Engineering package for the 3.2 mile Tysons underground section in conjunction with the Chamber of Commerce, the local landowners, and Tysons Tunnel, Inc.

The Station entrances were located within the proffered land and some private properties. The tunnel design is an alternative to the aerial structure proposed along street frontages of prime real estate and in the middle of Leesburg Pike, creating an 1800 foot long wall where no pedestrians or vehicles can cross. Tysons Corner is in a transition state where pedestrian access is critical to convert this “edge city” into a walkable, livable, and desirable community.

The station entrances are similar to the basement of typical high-rise buildings and can be designed for future development above. These can be constructed separately from the tunnel and will be connected once the tunnel structure is complete. KGP developed a concept that allowed light to penetrate down to the lowest levels of the platforms by creating an open circulation tube that comes to the surface and is covered by a glass canopy. The structure required buttressed walls that are articulated in cast in place concrete reflecting the exposed structure of the existing Metro system. Pre-cast concrete panels in combination with acoustic panels define the spaces between the buttressed ribs and provide spaces for speakers and electrical wiring. Lighting is mounted on beams similar to stage lighting and can be lowered to change the lamps. Service rooms are tucked in either over or under the mezzanine which sites off to one side. This variation in depth of the mezzanine creates balanced escalator lengths and stairs to keep each run within reasonable walking distances.