The 149-year-old Baltimore & Potomac Tunnel —  a major bottleneck for MARC and Amtrak trains along the Northeast Corridor — is set to finally receive a much-needed face-lift thanks to federal funding.

The Federal Railroad Administration (FRA), a branch of the U.S. Department of Transportation, announced Thursday that nearly $9 billion in grants will be issued to upgrade and expand passenger rail, with a focus on rehabilitating century-old bridges and tunnels along the country’s busiest rail lines. The Baltimore & Potomac Tunnel in Maryland, a 1.4 mile single-track stretch that was first built when Ulysses S. Grant was president, has existed in a dilapidated state for years, creating delays for the thousands of riders that use the corridor every day. Most Amtrak trains travel at a speed somewhere between 110 mph to 145 mph, but in the tunnel, trains slow to a crawl at just 30 miles per hour.

“Today’s investments are a major step towards reversing a half-century of underinvestment in vital rail infrastructure and will result in fewer delays for millions of riders and travelers,” FRA Administrator Amit Bose said in a press release.

In November, the Baltimore & Potomac tunnel was identified in the FRA’s Northeast Corridor Project Inventory — essentially a to-do list of projects with cost and allocation estimates — as a focus area for the Northeast Corridor. (In a 2017 report, the FRA found that it was “critical” to replace the tunnel within the next 10 to 20 years, as it “is approaching the end of its useful life.”)  Other major, century-old tunnels and bridges in need of repair include the Susquehanna River Bridge in Maryland, the Hudson Tunnel in New Jersey, and the Walk Bridge in Connecticut — all of which are listed a “backlog” projects by federal officials.

Amtrak, the federally chartered cooperation that will be project’s lead sponsor, plans to replace the current tunnel — deteriorating  from age and water damage — with two twin single-tracking tunnels. Once complete, the new tunnel, renamed the Frederick Douglass Tunnel, should allow riders to get from Baltimore to D.C. in less than 30 minutes, and significantly cut down ride times for other routes up and down the corridor.

“This funding will allow Amtrak to continue to operate and maintain America’s railroad in Fiscal Year 2023, including making important investments across our National Network, Northeast Corridor assets, and partnering with states on short-distance corridors,” Amtrak CEO Stephen Gardener said in a statement to DCist/WAMU.

It’s not clear how much of the $9 billion in federal grant dollars, set forth in the first round of funding of the Bipartisan Infrastructure Bill, will go toward the tunnel project. Projects are eligible to receive up to 80% of the projected cost, and money will be distributed through a federal-state partnership program. In 2021, when Amtrak and the Maryland Transit Administration unveiled the plan to revamp the tunnel, officials said it would cost $4 million and take between 10 and 12 years to complete, dependent on federal funding.