The deleted ventilation facility was also the thing Reservoir Hill residents sued over in 2024. Amtrak says the change was about cost.
Both can be true. In a July 28 program update on the $6 billion Baltimore and Potomac Tunnel Replacement Program — the largest single infrastructure investment in Amtrak’s history, the railroad and the Federal Railroad Administration disclosed a scope revision made “amid construction market conditions.” An intermediate ventilation facility and a smaller connecting tunnel are out.
Raising the alignment to cut excavation
The second change is pure engineering economics. The team raised the future tunnel’s track alignment at its deepest point by roughly 10 to 22 feet, which takes the maximum depth to about 150 feet below street level. Less depth means less rock, less muck haul, less shaft. On a bored tunnel of this length, a 20-foot vertical shift moves real money.
ADVANCE, an AECOM and Jacobs joint venture, is the delivery partner. Herrenknecht is building the two tunnel boring machines and the first one is 50% complete.
Work is visible elsewhere. Crews are advancing the new Mulberry Street railroad bridge, first of five bridges being reconstructed. In March, they broke through the final rock pillar separating both sides of a 345-foot utility tunnel that will carry water, sewer, communications and electrical beneath the tracks when it finishes in 2027.
What the program actually replaces
The existing B&P Tunnel is 153 years old and forms one of the tightest constraints on the entire Northeast Corridor, a 1.4-mile stretch where trains slow to a crawl. The Frederick Douglass Tunnel replaces it with two bored tubes for electrified Amtrak and MARC service, plus a new West Baltimore MARC station, 10 miles of rail infrastructure upgrades, and street and bridge work.
The CMAR contracts were let in two pieces: a Clark Construction and Stacy Witbeck joint venture took the southern approach in 2023, and a Kiewit and J.F. Shea Construction joint venture took the tunnel itself in 2024.
Amtrak president Roger Harris was careful about what’s ahead: “Replacing the 153-year-old B&P Tunnel is critical to improving safety and reliability along the Northeast Corridor, America’s busiest passenger railroad. Successful delivery of this program will continue to rely on support and collaboration from all our partners to address and mitigate current and future challenges.”
Opening is slated for 2036. Ten years out, and the program is already trimming scope to hold a number — which is worth remembering the next time a megaproject budget is described as final. Compare it with the design-build approach Rhode Island took, where the schedule risk sits with the contractor and the incentive structure is explicit.