Built for the Ages

Subway Going Strong, 100 Years and Counting

by James Murdock

Innovation in design and construction methods 100 years ago provided the foundation for 100 years of success on the New York City four-track system that still thrives today.

The most remarkable tribute to the 100-year-old New York City subway system is that engineers and contractors agree there is little they would do differently today if they were to build it again from scratch.

They would add more trunk lines through Manhattan and design better transfer points, to be sure, but the subway's basic infrastructure - its tunnel boxes and power system - would likely turn out the same.

"It was an extraordinary group of individuals who designed the original subway," said transit historian and author Brian Cudahy. "With the exception of the bells that go 'ding dong' when the train doors open and close, the technology today is not much different than it was 100 years ago."

The system celebrates its centennial anniversary this month.

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New York's subway engineers invented several new technologies and construction methods that have withstood the test of time, including the creation of a four-tack system to allow both local and express train service. Express service enabled New York's subway to move more passengers at a faster pace than any other subway before or since. It also had important consequences for engineering and construction.

When officials began planning a subway in the early 1890s, they looked to other cities for advice. London boasted the world's oldest system. Its first line, begun in 1863, was constructed using the cut-and-cover method: Streets were ripped up, a trench was dug for the subway and then temporary wooden decking was laid over it until construction was complete.

Cut and cover allowed for rapid progress because several tunnel sections could be constructed simultaneously, but the drawback was that it snarled street traffic and hurt local businesses. In later subway expansions, Londoners chose deep tunneling, a slower method that employed muck scrappers and was limited to the advance of a single tunnel face.

William Barclay Parsons, appointed chief engineer of New York's subway in 1894, toured the London Underground and was aware of the differences between the construction methods. He chose cut and cover for as much of New York's first subway as possible.

Cudahy said he believes that Parsons based his decision on two factors. Locating a four-tack system within deep tunnels would require installing extensive escalators and elevators to accommodate the increased passenger volume, and that would have been very expensive. And while London's clay soil is perfect for muck scrapping, New York's rocky and uneven ground requires drilling and blasting.

In a typical New York cut-and-cover tunnel, subway tracks lie roughly 14 ft. below ground level and rest on a bed of broken stone ballast. Beneath that is a 2-ft.-deep layer of concrete.

The side walls of the tunnel are made of reinforced concrete. Special pockets hold cables that supply electricity to the third rail. Steel I-beams capped by another layer of concrete comprise the roof.

"The subway is essentially a massive, self-contained concrete box," said Stanley Merjan, a professional engineer at Underpinning & Foundation Constructors Inc. "In addition to the concrete, it's got steel framing on the interior. It's a very rigid facility built with durability in mind and that's why it's lasted so long."

Subterranean Surprises Cut-and-cover construction was fairly straightforward, but relocating utilities such as gas and sewer lines was a significant challenge in the early 1900s. "You didn't have any maps and there was just a crazy quilt of utilities," Cudahy said. "Some of the water companies were still running wooden pipes, and electricity lines had been placed underground in a very rapid process after the great blizzard of 1888."

Reconnecting the utilities was also difficult given the meager 2-ft. envelope of space available between the tunnel box and the street. Engineers devised ingenious solutions. At 66th Street and Broadway, for instance, they subdivided two large gas mains, measuring 30 in. and 36 in. in diameter, into five smaller mains measuring 24 in. in diameter.

Given Manhattan's varied geology, cut and cover was only possible half of the original subway. The line contained three steel viaducts: one across the Manhattan Valley between 125th and 133rd streets, another from Dyckman Street to Bailey Avenue in the Bronx and one from Westchester Avenue to Bronx Park.

Deep tunneling was used as well. Underneath the Harlem River, two prebuilt cast iron tubes were sunk to form a 1,500-ft.-long tunnel.

Rock tunneling was necessary at Murray Hill in Midtown and again at Fort George in upper Manhattan. This work proved especially perilous. Cudahy said that of the 60 or so men who died during construction of the first subway, most perished in rock blasting gone awry.

One tunneling subcontractor, Ira Shaler, earned the nickname "the voodoo contractor" after several explosive mishaps. Shaler's luck eventually ran out in June 1902 as he was giving Parsons a tour near Park Avenue and 37th Street.

"Parsons pointed to a rock and said it looked rotten," said Clifton Hood, associate professor of history at Hobart and William Smith Colleges. "Shaler disagreed, stepped out from under a protective cover and tapped the rock with his cane. It all came down on top of him. He died a few days later. It was not a good way of losing an argument."

The deadliest construction accident occurred in October 1903 during construction of the Fort George tunnel. Ten men lost their lives after a cave-in.

When this 2-mi.-long section was eventually complete, though, it held the distinction of being the world's second longest two-track railway tunnel. Even today it remains the deepest portion of New York's subway. Shafts originally dug to access the construction site, 180 ft. below the surface, are now used by passenger elevators at the 168th and 181st Street stations.

Just up the line, the Dyckman Street station also ranks among the subway's most interesting stations, said transit historian and author Joe Cunningham. "Not only was it built at the mouth of a tunnel, it has grade-level and elevated portions," he added. "Model railroaders like do the same thing, to show off as much stuff as possible, but it's not usually thought of as realistic. At Dyckman Street you get it all within 600 ft."

No matter the terrain, labor conditions during construction of the first subway were by no means pleasant. "A lot of the work was literally just digging a hole with hand tools," said Joshua Freeman, chair of the history department at the CUNY Graduate Center. "It was a lot of unskilled labor."

The majority of laborers were recent Italian immigrants, but there were also plenty of Irishmen. African-Americans, meanwhile, were employed to construct tunnels under the Harlem River out of the mistaken and racist belief that they worked better in pressurized air locks, Cudahy said.

Wages for unskilled laborers averaged between $2 and $2.25 a week, roughly $46 in today's currency. Skilled laborers did little better, earning $2.50 a week.

Uplifting Underground Architecture Among the most skilled laborers were the masons employed to install tiles and tile mosaics on the walls of passenger stations.

John Kriskiewicz, an architectural historian and lecturer at the Parsons School of Design, said there were several reasons why tiles were used. Early subway stations were lighted by a combination of incandescent bulbs and sunlight, which was emitted through grates and glass blocks in the ceiling. The glazed tile, a highly reflective material, was ideal for boosting light levels.

Tile was also easy to keep clean and this helped present a sanitary atmosphere, something that health officials were concerned about in 1900 given New York's raging tuberculosis epidemic.

But there was also a more profound reason why decorative tiles were used. "Parsons wrote that the subway was more than just a transportation project," Kriskiewicz said. "It was to be a permanent civic work, just like the New York Public Library or Grand Central Terminal that would be spiritually uplifting."

In the earliest subway stations, mosaics depicted scenes that related to the name of the station. At Fulton Street, for instance, there were depictions of Robert Fulton's steamboat the Clermont, and at Astor Place were pictures of beavers to symbolize how John Jacob Astor made his fortune in the fur trade.

Station art evolved in later years in keeping with changing tastes. By the last round of subway construction in the 1930s, bold geometric lines were in vogue as part of the machine aesthetic.

Another difference in stations built during later subway expansions relates to their size. The original subway planners underestimated ridership and as a result early stations were prone to overcrowding. Accordingly, later engineers designed wider platforms, added more exits and constructed mezzanine levels to allow for better pedestrian circulation.

There wasn't always room to build mezzanine levels, though, and this forced subway engineers to find imaginative ways of carving out more space underground. At Penn Station, for instance, space is extremely limited and so the downtown and uptown platforms are staggered.

Creative solutions will be necessary once again as the Metropolitan Transportation Authority begins work on new subway projects. And on the No. 7 project, the MTA has sought design assistance from a familiar name: Parsons.

"Our firm has been able to work for New York City Transit in its various configurations for 100 years," said Tom O'Neill, president & CEO of Parsons Brinckerhoff Inc. "To have a client relationship that lasts 100 years is tribute enough. It's very hard to maintain any kind of relationship that long, and one of our missions is to have it last another 100 years."