Washington Metropolitan Area Transit Authority
The Potomac Yard Metrorail Station is a new WMATA infill station on the existing Yellow and Blue Lines in Virginia that will be a catalyst for new mixed-use TOD in northern Alexandria. WMATA studied three pedestrian bridge options over the existing CSX and Amtrak tracks that separate Metro from the development site and below grade connections proved infeasible due to the floodplain and proximity of the river. KGP’s design reflects the need for continuous operations of the adjacent tracks and mitigates interference with rail operations carried out by CSX, Amtrak, Virginia Railway Express, and Metro.
The station design has undergone a rigorous public approval process with a wide variety of stakeholders including City of Alexandria, NPS, CFA, NCPC, Amtrak, and CSX. There were weekly meetings for about 15 months with the City of Alexandria, and bi-weekly meetings with the city, National Parks Service, Parks and Recreation, and other parties with direct or indirect projects in the area. During this process, there were approximately five public meetings with the Potomac Yard Metro Implementation Group (PYMIG) and approximately five meeting with the Board of Architecture Review (BAR) for the city of Alexandria. Through this process decisions concerning both the site and structure were decided. These discussions necessitated the station blend naturally into the George Washington National Parkway controlled by the National Park Service, while also offering an urban face on the west side to accommodate the developers who will ultimately pay for most of the station’s construction.
KGP was responsible for developing the station design and the 30% design-build documents including public spaces, service rooms, bridges, ramps, bicycle storage, and entry pavilions. The station uses side platforms with mezzanines at each end for access. The platforms are built on fill next to the active Metro tracks, raising it up from the surrounding wetlands, with service rooms are tucked in below the platforms. The Amtrak train clearance determines the heights of the bridges from the west, which in turn establishes the heights of the mezzanines. Access for construction is limited and must go through the Potomac Green neighborhood on the east. Once the station is complete, trains will be switched to the new alignment and crossover, which will take place over a long weekend.
The station is accessed from both the North and South entrances via a pedestrian bridge spanning over the CSX/Amtrak/VRE and WMATA rail corridor. The South station bridge include an elevated bicycle/pedestrian ramp providing a critical urban connection between the isolated Potomac Greens neighborhood on the East and the rapidly developing Potomac Yard neighborhood on the West. The bridge design was driven by the minimal time allowed for a shutdown of the CSX rail line. Because of this, the bridges are designed to be simple spans with a maximum span of 150’ and are light enough to be installed in a single crane pick. Each bridge over the existing rail corridor is a steel warren truss bearing on concrete piers with stone cladding. The bicycle/pedestrian ramps are a concrete deck on steel framing supported by randomly oriented steel posts that blend in with their wooded environment.
The station aesthetics were a critical part of the design process. A yearlong review with weekly presentations by KGP to the local officials and National Park Service was required. The conclusion was a glass and steel enclosed structure that has a relationship to nearby historical industrial buildings. The station is naturally ventilated and shaded with steel louvers and the bridges and entry pavilions have a similar aesthetic. Secure bicycle storage is provided below the bridges.