Iconic Verrazzano-Narrows Bridge Turns 60

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WSP’s History with Verrazzano-Narrows Bridge

In writing this article, Informed Infrastructure Editorial Director Todd Danielson interviewed via webcam Jonathan Morey, P.E., senior bridge engineer at WSP USA; and Stuart Rankin, senior vice president at WSP USA, national bridges and structures practice.

To learn more about this special bridge, its famous designer and what it meant to the engineers who worked on it as well as engineering details about orthotropic deck, Vierendeel trusses and main-cable dehumidification, watch the full video interview above or at bit.ly/3PytTH2.

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New York City is famous for many landmark structures of all types, including buildings such as The Empire State Building, One World Trade Center, Rockefeller Plaza and the Flatiron and Chrysler Buildings. It has historic and world-class churches and museums, and it’s most-famous landmark is the Statue of Liberty.

The city also is home to many of the most-famous bridges in the United States, if not the world. Many people worldwide are familiar with some of the names and silhouettes: George Washington Bridge, Manhattan Bridge and, of course, the most famous of them all: the Brooklyn Bridge.

But in engineering circles, none may foster as much respect and reverence as the Verrazzano-Narrows Bridge, which celebrated its 60th birthday in November 2024 and was the largest suspension bridge in the world when it debuted in 1964 (and for the next 14 years), slightly longer than the Golden Gate Bridge in San Francisco.

“The sheer size of the bridge—as well as the foresight that was put into the planning of the structure so it would last this long without major modifications to its ability to carry the traffic flow—says a lot about the engineers at the time in their forward thinking,” says Jonathan Morey, P.E., senior bridge engineer at WSP USA.

A sequence of images shows an artist’s preconstruction drawing of the bridge circa 1960 (top), a photo upon completion in 1964 but before the second deck was added in 1969 (middle), and a photo of the recently completed reconstruction and widening of the bridge in 2024 (bottom)

The History

Discussion to build a bridge or tunnel connecting Staten Island to Brooklyn began at least by the 1920s, as the only way to reach any of the city’s other boroughs required a ferry or traveling via bridge to New Jersey to the west before taking other bridges further north. An extremely complicated political backstory includes proposed plans of several tunnels and bridges to connect Staten Island and Brooklyn via the “Narrows,” the shortest distance between the islands to access New York Harbor. There’s also a very complicated (and sometimes contentious) backstory on naming the bridge, as it took many years of Italian Historical Society of America lobbying to add recognition to Giovanni da Verrazzano, who in 1524 was the first European explorer to enter New York Harbor and the Hudson River.

Eventually, a bridge solution won primarily due to the higher costs needed to construct a tunnel, but plans were delayed due to more politics until construction began in 1959. A very important element of the bridge’s appeal to present-day bridge engineers is the lead designer of the Verrazzano-Narrows Bridge, Othmar Ammann, a legendary engineer who also developed New York City’s George Washington Bridge, the Triborough Bridge and the Lincoln Tunnel. He also assisted with the Golden Gate Bridge and attained fame writing reports about the Tacoma Narrows Bridge, which famously and horrifically collapsed in 1940.

Ammann was best known for creating suspension bridges that were light, inexpensive, simple and beautiful. The Verrazzano-Narrows Bridge may be his engineering masterpiece.

Bridge Details

With a central span of 4,260 feet and a total length of 13,700 feet, the Verrazzano-Narrows Bridge still ranks as the 13th-longest suspension bridge in the world and the longest in the Americas. It consists of 218,000 tons of steel (more than three times used in the Empire State Building), 1.4 million tons of concrete and 143,000 miles of cable wire.

 

 

A unique aspect of the Verrazzano-Narrows bridge is that the deck was built starting in the middle and working its way toward the towers (top), which helped reduce the size and complexity of the towers. Since then, major suspension bridges followed that deck-erection sequence of starting in mid-main span. Famed bridge designer Othmar Ammann also utilized an innovative truss system (bottom) to make the 13,200-foot-long bridge possible.

 

The main suspension towers are 693 feet tall and are 1 5/8 inch further apart at the top than the base to make up for the curvature of the Earth across such a long span. Each of the two suspension towers contains approximately 1 million bolts and 3 million rivets, and they were at the time the tallest structures in New York City outside of Manhattan.

“When you’re dealing with smaller spans, [curvature of Earth] doesn’t need to be taken into account with such a level of intricacy,” notes Morey. “But when you have such a large span, the details matter, so you need to work it down to the fractions of an inch regarding the truss.”

Ammann designed the bridge with Vierendeel trusses, which allowed for the required strength without using triangular frames.

“In traditional trusses, usually the members act in compression or tension—only axial forces,” explains Stuart Rankin, senior vice president at WSP USA, national bridges and structures practice. “The Vierendeel truss is underneath the structure. Along the sides of the structure, there are two stiffening trusses with diagonals with the Vierendeel connecting one truss to the other truss. In essence, the floor system underneath the bridge is a Vierendeel truss. If you’ve ever driven the lower level of the Verrazzano-Narrows, essentially you’re driving through the trusses.”

 

A renovation project concluded in 2024 includes a new and lighter bridge deck, new tolling and signaling, improved on and off ramps, and an added high-occupancy vehicle lane.

 

This also allowed a second deck to be added below the first without blocking vehicles. Ammann specified extra trusses to be built for a second deck, which, due to unexpectedly high traffic volume, was added in 1969, nine years before original projections. The population of Staten Island also dramatically increased after the bridge’s opening connected the most-rural borough to the others.

“Prior to the construction of the bridge, Staten Island was somewhat isolated,” notes Rankin. “The ability to connect communities, which results in increased commerce and ease of commuting, allowed the development of Staten Island as a residential area.”

Recent Upgrades

All bridges require regular inspection and maintenance, and the Verrazzano-Narrows Bridge is no exception. After decades of minimal and routine upgrades, New York City began a major reconstruction project in 2011 to add a seventh high-occupancy vehicle lane to the upper deck as well as replace the deck to make it lighter and increase its load capacity. Additional improvements were made to the lighting and tolling systems as well as other minor functional and cosmetic improvements.

Major work also was done to improve access to the bridge, so on and off ramps were rearranged and rebuilt to improve traffic flow and allow for the reversible center lane.

Lasting Effects on Engineers

Rankin has spent much of his life in the New York City area, and he and other locals consider the Verrazzano-Narrows Bridge to be just as special as its more-famous neighbors that connect to Manhattan. “As an engineer who focuses on suspension bridges, the Verrazzano-Narrows Bridge is special,” he explains. “I am quite fortunate and lucky to be able to say I’ve crawled over almost every inch of that bridge.”

“To me, the Verrazzano-Narrows Bridge is kind of a beacon to bridge engineers, almost like a ‘call to,’” adds Morey. “If you’re able to work on the bridge and reach back in time and touch that engineering excellence, it’s almost like you’re able to hear the voice of Othmar Ammann, and it’s pretty moving, I think, for us.”