Thursday, September 8, 2011

City of Bridges

by Conroy


New York, perhaps the world's greatest city, is renowned for many things. The largest city in the United States, and one of the largest in the world, it's a center of world culture, commerce, finance, education, entertainment, and international affairs. The city is densely sprawled over five boroughs situated on three islands - Manhattan, Long Island (Brooklyn and Queens), Staten Island, and the mainland (the Bronx). Probably the first image that comes to your mind when thinking of New York is its famous skyline. The city, and especially Manhattan, is synonymous with that great American invention, the skyscraper. However, if you let your thoughts fall from all those celebrated buildings, and think about how the city's islands are linked (to each other and the mainland), perhaps you'll recall some of New York's other great engineering monuments - its many outstanding bridges. Indeed, for someone captivated by large bridges, such as myself, there can be no better city in the world to visit than New York, the city of bridges.

Last weekend a couple of friends and I drove to New York to watch the U.S. Open. Leaving New Jersey we crossed the Goethals Bridge to Staten Island, went across the Verrazano-Narrows Bridge into Brooklyn, and past the Brooklyn Bridge, Manhattan Bridge, and Williamsburg Bridge on the way to Queens. Each distinctive and impressive, but these exemplars are only a fraction of the total. All told there are 37 major road and rail (or combination) bridges in the city. They include all major forms:
  • arch (Alexander Hamilton, High, Washington);
  • bascule (Greenpoint Avenue, Pelham, Pulaski);
  • beam (Rikers Island);
  • cantilever (Goethals, Queensboro, Outerbridge);
  • causeway (Cross Bay Veterans Memorial, Joseph P. Addabbo);
  • steel arch (Bayonne, Hell Gate, Henry Hudson);
  • suspension (Brooklyn, Bronx-Whitestone, George Washington, Manhattan, Robert F. Kennedy (formerly the Triborough), Throgs Neck, Verrazano-Narrows);
  • swing (145th Street, City Island, Macombs Dam, Madison Avenue, Spuyten Duyvil, University Heights, Willis Avenue);
  • truss (Kosciuszko, Third Avenue), and;
  • vertical lift (Arthur Kill, Broadway, Marine Parkway, Park Avenue, Roosevelt Island).
The Historic
This long list includes the historic, the massive, and the beautiful. Let's start with the historic, and the Brooklyn Bridge. The bridge spans the East River and connects lower Manhattan with northwest Brooklyn. It was designed by the famous bridge builder John Roebling and completed by his son Washington; construction spanned the years 1870 to 1883; it is one of the oldest suspension bridges in the country. At the time it was built it was the longest suspension bridge in the world. It represented a leap in engineering and is a forerunner of the great suspension bridges built in the twentieth century. Its combination of engineering innovation, impressive size (especially for the time), and distinctive architecture have made it a New York icon and one of the most recognizable bridges in the world.




The Brooklyn Bridge is also one of the great walking bridges. A pedestrian (or bicyclist) can cross on an elevated path above the center of the bridge. The crossing offers spectacular views of the Manhattan skyline, New York Harbor, and the Statue of Liberty.

Queensboro Bridge
Other crossings of the East River soon followed, with the Manhattan Bridge, Williamsburg Bridge, and Queensboro Bridge constructed in the the first decade of the twentieth century. The latter (now formally - and somewhat unpopularly - known as the Ed Koch Queensboro Bridge), is a steel cantilever bridge that connects midtown Manhattan and Queens. Movie fans will recognize this landmark from the memorable bridge scene in Woody Allen's Manhattan. Thirteen of New York's bridges are a century or more old.

The Massive
Some of the city's bridges are both old and massive. The George Washington Bridge spans the Hudson River between northwest Manhattan and New Jersey. The suspension bridge opened in 1931 and featured the longest central span in the world, a title it would hold for five-and-a-half years until the Golden Gate Bridge was completed. It's still one of the twenty longest suspension bridges in the world.

George Washington Bridge
It's also the only bridge crossing of the Hudson River in New York City, which makes it a very popular route. In 1962 a second, lower, deck was added bringing the total number of lanes to fourteen, and providing the bridge with more capacity than any other. It has the distinction of being the busiest vehicular bridge in the world, carrying more than 100 million vehicles a year.

As noted above, the George Washington Bridge span was surpassed by the Golden Gate Bridge in 1937, which remained the world's longest span until 1964 when another New York bridge, the Varrazano-Narrows Bridge, took back the title. The Varrazano-Narrows spans the Narrows separating New York Harbor from the Atlantic Ocean. The bridge connects Staten Island and Brooklyn and is the only road link between Staten Island and the rest of New York (State and City). Like the George Washington Bridge, the Verrazano-Narrows Bridge is double-decked. It remained the world's longest suspension bridge until 1981 when the Humber Bridge opened in northern England.

Verrazano-Narrows Bridge

The Beautiful
Williamsburg Bridge
As an engineer I'm always impressed with long spans like the George Washington and Verrazano-Narrows bridges, but there's something special about structures whose aesthetics enhance their surroundings. Of the "famous" New York bridges, my favorite is certainly the Williamsburg Bridge. Its beauty surpasses that of any of the city's other suspension bridges. I love its tapering open frame steel towers, the lattice truss around the roadway, the stark steel gray color. And it was an engineering feat in and of itself, surpassing the Brooklyn Bridge as the world's longest span in 1903, a record it held until 1924.

[If you're keeping track, that's four of New York City's bridges that held the title for the longest span in the world - Brooklyn - Williamsburg - George Washington - Verrazano-Narrows. Only nineteen bridges have ever held that distinction.]

Hell Gate Bridge
But perhaps the most beautiful New York Bridge is the Hell Gate Bridge, which carries rail traffic over Hell Gate (a straight of the East River) between Queens and the Bronx. The steel arch bridge looks like a smaller version of the iconic Sydney Harbour Bridge, and indeed it served as an inspiration for that structure. The ornate beige masonry towers, iron red steel, straight railway, parabolic lower arch, and sweeping upper arch make for an engineering masterpiece. A model combination of elegance and functionality. This type of structure is known as a through steel arch, which means that the steel arches rise above the roadway (or railway) making it appear to pass through the arch. Cables support the section of roadway under the arch. The Bayonne Bridge is another example in New York, but while it may be the same type of bridge it's no match for the Hell Gate's beauty.

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I've seen, driven, or walked many of New York's bridges, but there are many that I still need to experience up close. A few years ago a good friend took a cruise around Manhattan, there must be no better way to see the so many, and the great variety, of the city's bridges. This will have to be part of a future visit to New York.

2 comments:

  1. One of my favorite pastimes in NYC is to ride my bike over the Brooklyn Bridge. Every time I ride, I notice something new that I haven't noticed before.

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