WASHINGTON, D.C. – Construction of the first phase of an ambitious infrastructure improvement project that will deck over I-395 in the nation’s capital to create space for new businesses and residences, was recently completed thanks in part to the design expertise of STV, a leading transportation engineering firm. Known as Capitol Crossing, the project will create three new city blocks and five new mixed-use buildings.
Working with the developer Property Group Partners and the District Department of Transportation (DDOT), STV is serving as engineering consultant for the tunnel and roadway infrastructure component of Capitol Crossing. Once this $1.5 billion initiative is complete, Capitol Crossing will reunite F and G streets as well as Second and Third streets as originally designed under Pierre L’Enfant’s 1791 master plan by using the air rights over the busy Interstate 395 artery to build a deck that will support 2.2 million square feet of residential, retail and office space.
“This is a transformative project that will add value and inject vibrancy into the central business district while at the same time reconnecting and restoring the city’s historic master plan,” said Michael Randolph, P.E., STV’s engineering director and project manager. “We are proud to have offered our expertise for such a visionary plan.”
Since 2010, STV has provided civil/highway, roadway, traffic, structural and tunnel engineering services along with a security analysis that met with Federal Highway Administration criteria, for this project. Previously, STV had completed preliminary engineering and an environmental assessment in accordance with NEPA requirements.
During the planning phases, STV evaluated a series of alternative interchanges that would permit construction of the deck. The firm later identified construction impacts to the transportation network, the tunnel ventilation systems, and fire and safety egress, while also performing a security risk assessment for bridges and tunnels. Working closely with DDOT, STV helped refine the final transportation plan to balance vehicular, transit, pedestrian and cyclist needs in terms of capacity, operations and safety.
In addition to designing the structural and tunnel engineering plans, STV is providing all of the traffic signaling, signing and pavement marking plans along with lighting and intelligent transportation systems and communications for the project’s transportation infrastructure. Working with DDOT, the firm also developed a comprehensive construction staging plan that has enabled I-395 to remain open during construction.
The first phase of the project included the installation of an efficient utility system, including a high-voltage electrical line along Massachusetts Avenue from Third to Fourth streets. This infrastructure project reconnects the area to the district’s grid while stabilizing the electrical supply and increasing capacity to meet the needs of more residents. New water mains, upgraded gas lines, and telecom utilities were also installed.
The second phase encompasses the vertical component initiative. The first of five buildings, 200 Massachusetts Avenue, NW, is currently under construction. It features almost 30,000 square feet of retail on the ground level and about 400,000 square feet of mixed-use space. The building’s construction is expected to last until 2018.
