Hoosac Tunnel still matters

Politicians love to talk about infrastructure, even though they rarely get anything done about it. Over the past few months, you would have had to have been a hermit to have missed all the posturing and pontificating in the name of better bridges, highways, and tunnels.

One thing you don’t hear as much about is how little of this applies to America’s freight railroads, which are doing fine taking care of business mostly on their own. Funny how much you can get done with private money when debating is beside the point.

What amazes me is how much of our railroad infrastructure is comparatively ancient. I’m thinking here of CSX’s Thomas Viaduct in suburban Baltimore (1835), or St. Louis’s light-rail Eads Bridge (1874), or CSX’s Cowan Tunnel in eastern Tennessee (1853). The civil engineers of the 19th century knew how to make things last.

Which brings me to Hoosac Tunnel in western Massachusetts, historically the pride of the Boston & Maine Railroad and today still an asset of Pan Am Railways.

Even after 144 years, Hoosac still matters. Just ask Canadian Pacific, which in recent weeks has asked the Surface Transportation Board to intervene in a proposal by CSX and Pan Am that, CP says, would inevitably lead to the downgrading or perhaps even elimination of the former B&M route through the tunnel. CP has a keen interest in Hoosac: most of its New England traffic funnels that way via Mechanicville, N.Y.

The story of how CSX and Pan Am intend to redraw the New England railroad map is too complex to explain in this space, although Trains columnist Bill Stephens offers an excellent analysis on the magazine’s News Wire. Suffice it to say that CSX’s and Pan Am’s plans dovetail nicely with what another Hoosac user, Norfolk Southern, wants in the region, but not CP.

Meanwhile, I can’t help but root for Canadian Pacific, if for no other reason than I’d love to see Hoosac continue to do what the long-gone Troy & Greenfield Railroad, a B&M predecessor, intended when it finished the bore in 1877: allow trains to crest the Berkshire Range with relative ease. 

Hoosac Tunnel was a genuine marvel when it opened, stretching for 25,081 feet, or 4.75 miles, beneath Hoosac Mountain, the principal barrier between the watersheds of the Hudson and Connecticut Rivers. At first it was the longest tunnel in the world, a status it held for nearly a decade; Hoosac kept that title in the U.S. for nearly 40 years. The late William D. Middleton, the leading scholar of railroad engineering, called Hoosac “the greatest American tunneling of the 19th century.”

The tunnel’s builders paid a dear price for fame. It took 22 years for crews to scrape and blast their way through limestone, slate, and gneiss, the latter among the oldest metamorphic rocks on Earth. The first several years were an interminable slog of manual drilling and black-powder blasting, a job greatly speeded up with the arrival later of compressed-air drilling and nitroglycerin blasting. All told, 191 workers were killed over the scope of the project, an awful statistic. 

Throughout its long duration, construction of Hoosac Tunnel attracted a who’s who among early American civil engineers, among them surveyor Theodore Cooper, who invented the bridge rating system that bears his name; Herman Haupt, who left the Hoosac project to lead Union military railroads during the Civil War; and Benjamin Latrobe, who designed B&O’s Thomas Viaduct.  

Over the years Hoosac also hosted all three basic forms of motive power — steam, electric, and diesel — a distinction it shares with a number of important U.S. tunnels, among them Elkhorn Tunnel on the former Norfolk & Western in West Virginia and Cascade Tunnel on the ex-Great Northern in Washington. When longer trains and bigger steam locomotives threatened to asphyxiate engine crews, the B&M in 1911 installed 7.6 miles of electrified railroad. The 11,000-volt, single-phase A.C. system was designed by engineers from the New Haven Railroad and employed a fleet of Baldwin-Westinghouse box-cabs.

The wires came down in 1946 with the advent of diesels on the B&M and the installation of an improved ventilation system. The tunnel was single-tracked in 1957 to improve clearances for piggyback, then enlarged again in 1998 to accommodate double-stacks.

The tunnel has not been without occasional problems. In early 2020, a partial wall collapse at the west end closed the bore for 52 days and required the installation of a new liner with 40 steel arches, steel plate, and shotcrete. Once repaired, the tunnel was back to hosting six to eight trains per day.

The outlook for Hoosac Tunnel isn’t necessarily gloomy. In its filing with the STB, Canadian Pacific is seeking requirements that the old B&M route be kept open and at the very least maintained to support current service. “Though [the] Hoosac Tunnel route hosts relatively few daily freight trains, it serves as a vital and unique competitive discipline to CSX, which dominates traffic volumes,” writes James Clements, CP’s vice president of strategic planning.

I’ve never had the privilege of riding through Hoosac Tunnel; I’m envious of my editor, Rob McGonigal, who rolled through it in a 2015 Amtrak Autumn Express. But I did visit the east entrance in the late 1990s and recall being a bit awed by its imposing portal with the stone dated “1877” above the arch.

I hope the STB will have the good sense to help this marvelous example of infrastructure — designated in 1975 as a Civil Engineering Landmark — keep doing what it was designed to do 144 years ago: play a useful role in interstate commerce.