The updated plan proposes incorporating a new two-level, 40-slip intercity bus terminal into the facility, with a direct connection to the train hall. On-site parking availability would be scaled back from the originally proposed six-level, 1,600-space parking garage—already smaller than Union Station’s existing 2,200-space structure—to no more than 550 spaces, all located beneath the station’s rail tracks, along with vehicle pick-up/drop-off functions.

The railroad agency says that while a smaller parking element located underground require a “substantial cost” and reduce an existing revenue stream from on-site parking, the move also “creates more opportunity for commercial development and public space above the tracks.” 

Opened in 1908, Union Station is one of the nation’s busiest transportation hubs. Prior to the pandemic, the facility handled 37 million visitors traveling via Amtrak, Maryland and Virginia commuter rail systems, the Metrorail subway, local buses and streetcars. The agency projects Amtrak ridership to and from Union Station to nearly double by 2040, while the commuter lines could see significantly larger gains during that period.

The agency calls the $8.8 billion to construct the supplemental review's preferred alternative “a rough-order-of-magnitude estimate” that is subject to refinement as planning and design progress. The estimate includes escalation over the duration of construction, which it projects will unfold in multiple phases over 13 years. 

The non-profit Union Station Redevelopment Corp., which acts as landlord for Union Station, would implement the expansion project through final design and construction and manage mitigation measures identified during the National Environmental Policy Act (NEPA) process. The non-profit previously oversaw the mid-1980s addition of retail to Union Station’s historic 219-ft-by-120-ft Great Hall, and completed a five-year $20-million renovation of the space in 2016 to upgrade structural and building systems, and repair damage from a 2011 earthquake.

The agency notes that the expansion project would complement investments in intercity passenger service on the Northeast Corridor and south of Washington, D.C., including a project to build a new two-track bridge adjacent to the existing Long Bridge that would provide much-needed capacity to the Potomac River crossing that has long been congested with both passenger and freight trains.

Following a review of comments received during the supplemental draft review period, the railroad agency plans to complete the process by publishing a Final Environmental Impact Statement and Record of Decision in January. In a statement, the agency expressed hope that local and other entities will partner in funding the expansion project and “ensure the continued viability of the station.” 

The non-profit organization InfrastructureDC, is partnering with the District of Columbia government to study alternatives to complete the upgrade, including identifying optimal project delivery, financing and governance mechanisms.