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.

与原始估计相比，相对便宜的成本是替换隧道的原始估计多达30亿美元。但是，通过降低现有的地板和/或提高天花板来创造所需许可的建筑策略已将可能是破坏性的魅力城市风格的大挖掘变成了更可口的，几乎是全面的努力。

Maryland and CSX are counting on the project’s relatively low cost and myriad potential economic benefits to the city and surrounding region to做一个成功的案例1美元55 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 loveto 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.

无聊的一个新的隧道通过th 115英尺下的岩石e surface would more than double the current daily throughput of approximately 140 Amtrak, MARC commuter rail, and occasional freights.

This plan isnot 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.