Largo Town Center & Morgan Boulevard Metro Stations
A design-build project, the Largo Town Center & Morgan Boulevard Metro Stations project was completed nearly two years faster than any other single station that followed the Washington Metropolitan Area Transit Authority’s (WMATA) traditional design-bid-build method. The project team designed and built two stations, large parking structures, and a day care center.
The WMATA project included design and construction of two station facilities at Morgan Boulevard and Largo Town Center. The stations incorporated a new look for the station platform and mezzanine canopies, in addition to wider platforms (30 feet compared to the existing 28 feet on current platforms). Features also include elevators from the platform to the mezzanine and kiss-and-ride and bus bays at both stations. The Morgan Boulevard Station also houses a child care facility and surface parking for 596 park-and-ride vehicles. The Largo Town Center Station incorporates two parking structures that can accommodate 2,100 vehicles. The communications systems for both the Morgan Boulevard and Largo Town Center stations include integration and routing of CCTV, public address, radio, digital display signs, and telephone systems. The team also developed and managed the System Integration Plan at both stations.
The sites for the new stations each posed unique challenges. Both had very poor soil quality. The project team incorporated ground improvements into its design to counter this, and by value engineering the design of track slabs, reduced the needed thickness of the slabs. The Largo Station site was previously a parking lot and required significant re-grading to achieve the 17-foot offset required for the upper and lower station entrances. All of the new structures at this site used deep foundation systems. The track work and platforms were founded on six-foot drilled shafts. The two parking structures were placed on over 800 steel piles. The Morgan Station site was heavily wooded at the start of construction. The Station was located in a cut and required over 40,000 cubic yards of excavation, the installation of significant support of excavation at the interfaces with the adjacent contracts, as well as placement of over 120,000 cubic yards of borrow fills to level the site for nearly 600 parking spaces. During construction of the station invert, a previously unidentified zone of extremely loose sand required the installation of over 100 displacement piles to provide the necessary support for safe operation of the trains.