Grover Cleveland was president and the Panama Canal was still a decade away from beginning its US-backed push to completion when the first freight trains started chugging through Baltimore’s Howard Street tunnel in the summer of 1895.

More than 120 years later, the 1.7-mile tunnel remains the shortest route from the Port of Baltimore to points north and northeast. But its single-track and relatively low 19.5-ft clearance make it an anachronism in an age of high-volume, double-stacked container trains.

And with the opening of an expanded Panama Canal on the horizon, the tunnel is hardly a competitive advantage for a city vying with other East Coast ports for a piece of the post-Panamax shipping action.

An additional 1.5 feet of vertical clearance is all that’s needed to make the Howard Street Tunnel suitable for double-stacked container. And the State of Maryland and owner CSX railroad are trying to make that happen through a proposed $425 million public-private improvement project.

The cost is a relative bargain compared with original estimates of as much as $3 billion to replace the tunnel. But a construction strategy that creates the needed clearance by lowering the existing floor and/or raising the ceiling have transformed what might have been a disruptive Charm City-style big dig into a more palatable, virtually all-underground endeavor.

Maryland and CSX are counting on the project’s relatively low cost and myriad potential economic benefits to the city and surrounding region to make a successful case for a $155 million USDOT FASTLANE grant.

If the grant is approved, construction could begin as early as 2018, with the tunnel carrying double-stacked trains by 2023.

Another 19th Century below-grade bottleneck may not be so easily resolved. Amtrak would love to replace the 1.4-mile Baltimore & Potomac tunnel, a relic from 1873 (Ulysses S. Grant was president, BTW) with sharp curves that limit both the speed and volume of Northeast Corridor traffic through Baltimore.

Boring a new tunnel through rock 115 feet below the surface would more than double the current daily throughput of approximately 140 Amtrak, MARC commuter rail, and occasional freights.

This plan is not terribly popular with residents, concerned about the effects of vibration and train movement on their homes. And at $4 billion, cash-strapped Amtrak would be investing a significant amount of its limited treasure to address just one of its many infrastructure issues. (In 2014, Amtrak CEO and President Joseph Boardman called planning for a replacement tunnel “a waste of time,” given the absence of national support for funding passenger rail.)

Nevertheless, the federal government is spending $60 million for planning and an environmental review, which has resulted in cuts to both the amount of additional acreage needed, and the number of displaced residents, businesses, and community facilities. An environmental impact statement could be issued in spring 2017.