Tappan Zee Bridge Legacy

Although discussion and debate of a Hudson River crossing began in the 1800s, countless obstacles stood in the way, including fierce local opposition and challenging engineering problems. By the 1950s, the tides had changed: Political consensus and engineering advances made it possible to embark on building what would be one of the most innovative bridges of its time in the United States.

Breakthrough Engineering

The area of the Hudson known as the Tappan Zee (named for the Native American Tappan people who once lived in the area and the Dutch word for “sea”) is a natural widening of the river that’s 10 miles long and three miles wide in places. To stabilize a bridge that would cross the river at one of its widest points, engineers had to tackle a substantial problem: how to provide massive foundations for a 1,212-ft wide navigation channel when the bedrock needed to anchor them was at a depth of approximately 250 feet. The common solution available in 1950 was to use long steel piles, but the number of piles needed represented an astronomical — and unaffordable — cost.

Drawing on experience gained building temporary harbors for the Allied Forces during World War II, engineer Emil H. Praeger devised a novel solution that would eliminate the need to anchor everything to bedrock: use the river’s natural buoyancy to support some of the weight. So, when the nearly $81 million Tappan Zee Bridge (more than $760 million in today’s dollars) opened in 1955, it was the first permanent bridge in the U.S. to be supported in part by airtight floating concrete boxes (it was also the ninth longest span in the world). These eight giant buoyant caissons provided enough upward force to carry 70-80 percent of the weight of the span and its load of traffic over the navigation channel. The approach made engineering history and the bridge earned a place on the National Register of Historic Places.

The Need For a New Bridge

The increasing spread of suburban communities through the Hudson Valley and the accompanying rise of automobile use made a river crossing north of New York City an urgent necessity by the start of the 1950s, although the need had been anticipated long before. In fact, 20 years before the bridge opened (and only four years after the opening of the George Washington Bridge in 1931), the U.S. Congress approved funding for a crossing between Nyack and Tarrytown . Over the years, many different sites were considered but, ultimately, the South Nyack/Tarrytown location was selected, in part, to avoid sharing toll revenue with New Jersey.

Beyond connecting population centers and regional highways in Rockland and Westchester counties, the Tappan Zee Bridge was a vital link between the upstate and downstate sections of the New York State Thruway. Approved in 1942, the Thruway started construction in 1946 near Syracuse. When the Tappan Zee Bridge opened nine years later, it linked the two portions of the roadway, giving the Thruway mainline a total length of 423 miles – the longest operating toll expressway in the nation. By the end of 1960, all 559 miles of the Thruway system were open, connecting Buffalo on the shores of Lake Erie, the state capital of Albany, and New York City. Prior to the Tappan Zee, the nearest Hudson River crossing to the George Washington Bridge  was 44 miles.

Driving Growth and Opportunity

From the day it opened in December 1955, the Tappan Zee Bridge powered significant economic currents on both sides of the river. Its impact was most dramatic in Rockland County, which evolved rapidly from a predominantly rural and agricultural area to a diverse and bustling suburb. In the first five years after the bridge opened, the county’s population increased 50 percent.

Within a decade, 500,000 square feet of industrial space was under construction in the county to satisfy the demands of the businesses and manufacturing companies that seized the opportunities the new bridge offered. By 1965, Rockland was averaging more than 3,000 new residential units per year , along with new post offices and other public services, including schools. Growth did not come without a cost, however: construction of the bridge displaced more than 100 homes in South Nyack as well as the village’s commercial center.

By contrast, the physical impact of the bridge in Tarrytown was far less extensive. Only a few small homes and one large estate - Hawthorne – had to come down to make room for construction of the new bridge. The social and economic impact of the bridge in Tarrytown and the adjoining communities in Westchester County, however, was substantial. The addition of the Tappan Zee to Westchester’s transportation corridor attracted hundreds of millions of dollars in new residential development to house a growing population, along with large-scale commercial construction for corporate giants such as General Motors, General Foods, and IBM. The opening in 1960 of the Cross Westchester Expressway (I-287) linked Rockland and Westchester with Connecticut and New England, and paved the way for a new corporate mecca parallel to I-287, known today as the Platinum Mile.

Gateway to a New Beginning

In Rockland and Westchester, new jobs stimulated population growth and housing demand for workers benefiting from the expanding job market and the growing opportunities on both sides of the Tappan Zee Bridge. Creating an important new gateway for the movement of people, goods, services, and materials, the bridge provided access to attractive locations for new corporate tenants and businesses in a burgeoning suburban region while providing industry with a fast and reliable river crossing.

Did You Know? 

The cost to build the Tappan Zee Bridge was $81 MILLION in the 1950s.

Its curved approaches and latticed main span made the Tappan Zee Bridge a striking sight as it crossed the Hudson River. What was even more remarkable about this historic structure was how the geometry and design of the bridge elements were adapted to address dramatic changes in foundation conditions that existed at different points along the crossing.

Five Separate Sections

Since the 3.1-mile distance from shore to shore was far too wide for a single span, engineers divided the bridge into 5 separate sections:

1: Causeway

Starting in South Nyack, the longest section was the 8,739-foot causeway, a concrete deck supported by horizontal steel beams resting on reinforced concrete columns spaced every 50 feet. With 166 spans in total, the simple span construction was also comprised of a stringer and deck superstructure, as well as footings on timber piles

2: West Deck Truss

Moving east towards Westchester, the next section was the 1,750-foot west deck truss. Portions of this section rested on solid concrete circular caissons and some of the smaller buoyant rectangular caissons (measuring 110 feet by 56 feet by 40 feet) which were partially supported by piles driven into the bedrock far below. The truss spans also included deck slab and steel trusses, along with the concrete columns supported by the caissons.

3: Main Span

The main span section of the bridge, over the navigation channel, comprised two anchor spans (1,204 feet) and two cantilevers flanking a suspended center span (1,212 feet), with the two anchor spans resting on columns supported by mid-sized buoyant caissons measuring 126.5 feet by 77 feet by 40 feet. The cantilever sections rested on the largest buoyant caissons measuring 190 feet by 100 feet by 40 feet. All the caissons in this section were secured by steel piles driven to bedrock.

4: East Deck Truss

The 3,250-foot east deck truss began at the eastern end of the main span, about 2.4 miles into the river from the western shore of Rockland and rested on reinforced concrete columns and circular caissons to rock. Although the east deck truss is longer than the west (13 spans versus 7), engineers used similar materials and processes, with the exception of the rectangular caissons – which were not used here. Rock is quite high here.

5: East Trestle

The final section, the 300-foot-long east trestle, was a concrete deck on multiple steel beams and concrete columns that rested on the rock escarpment at the river’s eastern edge.

Bridge-Builder Mastery

The extraordinary innovation of the bridge design can easily overshadow the skill and innovation used to build the bridge. Not unlike the Governor Mario M Cuomo Bridge, some of the 1955 Tappan Zee Bridge was prefabricated and transported to site for installation. For example, the rectangular caissons that supported the main span crossing of the navigation channel: eight watertight concrete boxes the size of small buildings — some 40 feet tall — and then move them 12 miles downriver. The ingenious approach meant more easily constructing the caissons in a deep basin along the shoreline in Havestraw, flooding them to make them float, easing them into the river and using tugboats to guide them to the bridge construction site.

And beyond the caissons, engineering mastery was evident in the design adaptations to the profile, superstructure and foundations to address what was going on deep beneath the water. From non-uniform geometry to short span lengths and shallow foundations where rock was not reachable to steep grades and longer spans where rock was reachable, the bridge designers implemented forward-thinking approaches to tackle the most challenging of problems.

The Wizardry of Construction

A leading technical journal, the Engineering News-Record, even marveled at the wizardry displayed in constructing the bridge, from casting and curing to welding and splicing. The magazine also applauded some of the labor-saving ingenuity displayed: scaffolding built on a truck that could be quickly driven around the caissons to wherever it was needed; the use of everyday tools to complete essential tasks such as an ordinary paint sprayer to apply compound to walls, an auto mechanic’s pneumatic wrench to tighten bolts, and lengths of standard garden hose, punctured at intervals, to spray water on concrete during curing.

A Floating Pier

Although the Tappan Zee Bridge was the first permanent river crossing supported in part by buoyant caissons, the approach was first used on the Hudson a few miles downstream for Pier 57 on Manhattan’s Lower West Side. That project was also designed by Emil Praeger, who later refined the approach for the Tappan Zee’s watertight concrete boxes.

To fully appreciate the engineering significance of the Tappan Zee Bridge, consider the problems that had to be solved before construction could begin. From geology to geography to cost, all impacted construction and design. The final challenge the bridge faced – one that the engineering of that era could not eliminate – was the impact of time.

River So Wide

The bridge project was controversial from the start, and no aspect of its design was more contentious than its location at one of the widest points of the Hudson River. There was a simple reason for the choice: no river crossing could be built within the jurisdiction of the New York Port Authority, which extended along a radius stretching 25 miles north of the Statue of Liberty in New York Harbor. The proposed Tappan Zee Bridge would cross the river just 1,200 feet beyond that boundary – far enough north to comply with the law and far enough south to serve traffic-generating areas in Rockland County and connect with the growing New York State Thruway.

River So Deep

The Tappan Zee Bridge earned its place on the National is best known and justly celebrated for its use of watertight floating concrete boxes that supported as much as 80 percent of the bridge’s dead load (i.e., the bridge itself and all its components) while alleviating stress on the stabilizing steel piles that extended to the bedrock of the river bed. The depth of water in the Hudson is not constant – with the depth of the river varying from approximately 40 feet under the main span to about 15 feet from the main span to near the Rockland shoreline.  

Bedrock, on the other hand, can be found 250 to 350 feet below the riverbed under the main span and more than 700 feet in the third of the river’s width near Rockland.  Above the rock, there is a mixed composition of organic silt and silty clay which forms the riverbed.

Design Change Lowers Costs

The use of buoyant caissons had a significant impact on the cost of the Tappan Zee Bridge by reducing the number of steel piles needed to support the structure. Even with the caissons, the bridge used more than two million linear feet of piles. Another significant cost-saving came from a re-engineered design for the superstructure of the bridge. The original plan called for a long-tied arch, which would have been aesthetically stunning but expensive – and difficult – to build and maintain. Indeed, when the design was sent out for bid, none came back. The solution was to leave every other aspect of the design unchanged but replace the arch with a cantilever truss that saved time and money and ultimately earned a place in the record books as one of the longest in the world.

A Daunting Clean-up

After more than 60 years of service, the Tappan Zee Bridge offered one last engineering challenge that was not part of its original plan: New York State environmental regulations required that it be completely dismantled, piece by piece, from the river that had been its home. The task was daunting, involving the removal of as much as 302,000 tons of concrete, nearly 47,000 tons of steel, more than 13,000 timber piles and more.

Nearly all of the salvage was destined for reuse, including material repurposed to create six artificial reefs to promote fish habitat in Long Island Sound. New York State even provided portions of the Tappan Zee’s 13 feet wide by 50 feet long concrete deck panels to counties in the state and other interested parties for $1 apiece.

For many years, residents of Rockland and Westchester counties argued the pros and cons of a Hudson River crossing between Nyack and Tarrytown. During this time, local and global events – including World War II, the Korean War, the spreading impact of the automobile on American life and advances in engineering technology, would help shape the debate about a bridge across the Hudson River at one of its widest points. In Bridge Stories, we present excerpts from moments in history in which advocates and protesters, local residents and bridge workers, talk about the impact the Tappan Zee Bridge and the New York State Thruway – both good and bad – had on their lives and their communities. You can go back in time and hear or read the actual oral histories under the Recollections section.

Advocates & Protestors

A Hudson River crossing at the Tappan Zee had gained supporters as far back as the late 19th century, but the issue only became immediate — and incendiary — after the U.S. Congress approved funding for a bridge between Nyack and Tarrytown in 1935. Arguments between opponents and proponents shot back and forth until technical obstacles tabled the debate, much to the opponents’ delight. However, the battle flared up again after World War II as the need for a crossing in between the increasingly congested George Washington Bridge to the south, which opened in 1931, and the Bear Mountain Bridge to the north — a bridge-less distance of 44 miles — became more urgent. Recent advances in engineering technology would make possible what had been infeasible a decade earlier.

Bridge Clash I 1936:

In the 1930s, opposition to a bridge between Nyack and Tarrytown was well-organized, observes Roger Panetta, an historian who studies American suburbs. He notes there were opinion polls in towns and local newspapers trying to build support both for and against the bridge. There were debates and grassroots organizations, and the argument, he suggests, was not really about the bridge itself but about modernization of the area, pitting people who wanted to keep things the way they were against those who saw the bridge as an opportunity to create a better way of life.

Bridge Clash II 1951:

After World War II, large infrastructure projects that created jobs and stimulated the economy gained favor as ways to avoid another Depression. For New York State, the signature project was the New York State Thruway, whose 426-mile long mainline made it the longest toll-road in the nation, including a bridge that would link Rockland and Westchester counties. Panetta notes that when the idea for a Hudson River crossing reappeared in the 1950s, the opposition was much weaker than it had been in the 1930s.

In 1936, he notes, the bridge had nowhere to go. There were no major road connections for it to make. In the second “Bridge War,” as the New York Times had termed the conflict, the Thruway served as a kind of “Trojan Horse” because it made the Tappan Zee Bridge a smaller part of a larger system, with connections to highways on the east side of the river and routes leading directly to New York City. At that point, he says, the bridge seemed inevitable.

At a time when the print media were the main source of news, the dramatic battles over the Tappan Zee Bridge made excellent fodder for newspaper headlines and stories, with determined resisters chasing surveyors away from the Hudson’s Rockland shore and politicians later arguing that the location of the crossing was ideal because it was beyond the range of any atomic bombs that might fall on New York City.

Local Residents

More than 125 houses in South Nyack were demolished or moved to make way for the Tappan Zee Bridge, impacting a larger number of residents in Rockland County as compared to Westchester County. New York State exercised its legal right of eminent domain to take possession of these properties. The State was required by law to provide compensation and it frequently improved its bid if the resident refused the first offer. Some homeowners were able to buy their property back from the State at a nominal cost and physically move their homes to new locations. Otherwise, businesses, farms, open land and recreational areas all disappeared to make way for the bridge and the New York State Thruway that used it to cross the Hudson.

Rockland was a park-like place of quaint villages and family farms before the coming of the Tappan Zee Bridge. One woman remembers a cow who lived in a field across from her house. Another said "we never locked our doors."

Access to the World

Gossip about a bridge circulated in Hudson Valley communities for quite a while before rumors turned to fact. Then things happened quickly. “The State gave me 90 days to leave my house,” recalls one resident. “My father bought property in Grand View [adjacent to South Nyack] and moved the whole house there on a barge,” recalls another. This link will take you to first-hand accounts of how residents raced to pack up their belongings and get out of the way before construction began.

Bridge Workers

Construction on the Tappan Zee Bridge began on March 12, 1952, and the bridge opened to the public on December 15, 1955. In the 45 months of construction, it was estimated that 10,000 different people worked on the bridge, with up to 1,000 employed on the bridge project at a time. One of the first companies to begin work was Construction Aggregates, Inc., of Chicago and New York City, which put in the footings for the bridge as well as the clusters of timber piles used as icebreakers.

During the peak of its work on the bridge, the company employed approximately 300 people. The Corbetta Construction Company began work on the buoyant caissons on February 26, 1953, under a $3.8 million-dollar contract with Merritt-Chapman-Scott, and the last concrete for the caissons was poured on August 28, 1953. More than 200 workers, most of them drawn from the town of Haverstraw in Rockland County, completed the project 28 days ahead of schedule.

By the time the bridge opened, reports suggested that beyond the number of workers employed on the project’s construction, the Tappan Zee Bridge would directly cause the creation of perhaps 50 or more permanent jobs. Toll collection would account for 35 jobs, and the rest would be a permanent paint crew for the steel portions of the bridge. This did not account for any jobs related to monitoring the bridge, although newspaper accounts mention that the caissons required constant monitoring and regular inspection to assure that the pumps that kept them dry (and therefore buoyant) were in working order.

The Tappan Zee Boom

Once the bridge opened, its impact on both sides of the Hudson was immediate and profound. "Rockland County exploded because of its relatively cheaper housing," recalls a Tarrytown resident. "From the first day, the bridge brought diversity, and that was a good thing." Here are some reminiscences from both sides of the Hudson of both immediate and long-term impacts of the Tappan Zee Bridge.

"Bridges are more than marvels of engineering," says Roger Panetta, a sociologist who studies and writes about suburban America. "They’re also social, commercial, political and economic connectors, and that is of equal consequence to the remarkable technology and engineering of the bridges themselves." Many who loved the "Old Rockland" believed that the bridge transformed a park-like county into a suburban sprawl. At the same time, though, Panetta observes, the bridge and its connections made it possible for many families to buy an affordable home. In the 1950s, he says, "that meant achieving the American dream, and we have to be careful not to undervalue that."

Headlines

At a time when the print media were the main source of news, the dramatic battles over the Tappan Zee Bridge made excellent fodder for newspaper headlines and stories.

Roosevelt Signs Tarrytown-Nyack Bridge Measure

State Engineers To Start Borings For Construction of 3-1/4 Mile Span

September 6, 1935 – President Franklin D. Roosevelt signed a bill in early September of 1935 that provided government approval for a causeway, bridge or tunnel connecting Tarrytown and Nyack. In its front-page story, The Irvington Gazette announced that engineers were expected to begin borings in the river to prepare for eventual construction.

Hader Voices Objections to Bridge Plans

Clarkstown Group Is Told Reasons for Opposition to Span Entering County at Grand View.

September 10, 1936 – About a year later, the opposition began to make its voice heard. Elmer S. Hader, Chairman of the Zoning Commission of Grand View, NY (a possible site for the crossing’s western terminus) and a leader of the movement against the proposed bridge, wrote a letter to the New York Times offering numerous objections and concluding “This very ugly type of bridge would destroy the beauty of the Tappan Zee.” At the same time, he took his case to affected communities. Local newspapers, like The Journal-News in Rockland County provided him with a platform – on the same day as they ran another front-page story reporting that the New York State Department of Public Works had opened bids for test borings for the proposed bridge.

Bridge Surveyors ‘Bounced’ In Grand View

Had Cut Down Tree, Zoning Head Claims

September 11, 1936 – The protest picked up a considerable amount of steam (and press coverage) when a team of bridge surveyors took their equipment onto Elmer Hader’s property in Grand View. While they were there, they cut down shrubbery, put axe marks on some trees and actually cut one own, whereupon Hader enlisted the assistance of the police chief and ran the surveyors out of town. The Journal-News plastered this event on its front page under a large headline, noting that resentment on the part of Grand View residents was high over the bridge being “forced down their throats.”

Bridge War Grows in Hudson Valley

Fight Started by Grand View Women Against Surveyors Wins Quick Support

Grand View, N.Y., September 13, 1936 – Protest against the construction of the proposed Nyack-Tarrytown bridge here at a point where the Hudson River is three and a quarter miles wide, which was started yesterday when indignant women of the village routed a group of surveyors who had invaded the community to survey the western anchorage of the bridge, gained considerable impetus throughout the entire Hudson Valley today. Throughout the day, village residents who voiced their protest last night at a mass meeting where they authorized the police officials to double the present police force of 12 men and to “arrest any surveyor who enters the village,” received numerous telephone calls and telegrams from equally irate citizens from Albany to New York pledging support in “your splendid fight.”

Span Borings Cause Grief

One Down 200 Feet in River Before Striking Hardpan, Engineer Says

October 29, 1936 – A front-page report in The Journal-News in late October suggested under a terse headline that the bridge project might be in deep water.

Commission Drops Hudson Bridge Project

Commission Decides, 2 to 1, To End Authority, Urge Abandonment of Plan, According to Report.

December 18, 1936 – The conflict was destined to end quickly. Opponents led once again by the indomitable Elmer S. Hader had proposed inviting New York State Governor Herbert Lehman and a group of officials to a meeting on a ferryboat in the middle of the Hudson where they could “see for themselves the folly of selecting a site at a point three and a quarter miles wide.” But it was science more than statecraft that stopped the bridge project: the technology of the day was simply unable to place pilings in the deep bedrock of the riverbed at an affordable cost.

Bridge Clash: 1951

In the 1950s, opposition to a Hudson River crossing was considerably weaker than it had been in the 1930s. One opponent argued that the location of the bridge was a basic error and, echoing Elmer Hader’s comment from 1936 that the bridge was “ugly,” called it a structure of “freak design.”

N. Y. Thruway Spokesman Gives Reasons for Proposed Bridge Site

The claim that the bridge was a planning blunder prompted a full-throated response from the chairman of the New York Thruway Authority, who offered eight major reasons to show that the bridge site was based on sound thinking.

Defense Apathy Seen In Queries on Bomb; Some Are Confused

January 25, 1951 – With the Korean War in full swing in 1951, military issues received a lot of attention – at least from local newspapers. For instance, New York’s Governor Thomas E. Dewey defended the location of the Tappan Zee Bridge on the grounds that it was outside the target area for an atom bomb aimed at New York. Elmer S. Hader once again appeared in the news when he supported two former Army officers who took issue with the Governor’s atom bomb argument and claimed that in its proposed location, the bridge was an “open invitation to disaster in case of war.” Meanwhile, the Rockland County Times reported that people “in all walks of life” were fatalistic about an atomic bomb attack to the point of apathy and confused by advice they were getting from Civil Defense authorities.

Army Permit for Thruway Span Granted

May 4, 1951 – Despite the criticism, the project moved forward, winning a crucial victory when it obtained a construction permit from the Department of the Army.

New York Times – December 16, 1955

Thruway Opened with Dedication of Last Toll Link

Harriman Talks at Ceremony Marking Completion of Bridge at Tappan Zee

DAYLONG FETE IS HELD
New 28-Mile Stretch Toured By Caravan
16 Pickets Oppose Jersey Spur

Sixteen friendly pickets joined Governor Harriman yesterday in dedicating the $60,000,000 Thruway bridge linking Rockland and Westchester Counties. The ceremony was at South Nyack, at the Western end of the 15,764-foot span that twists across the Tappan Zee at Tarrytown. It was the highlight of daylong exercises that started at Suffern and ended twenty-eight miles away at Yonkers. The opening of that stretch signaled the completion of the entire toll length of the New York – Buffalo Thruway. 

In 1935, Congress approved funding for a bridge connecting Rockland and Westchester counties. Yet no amount of legislation could overcome the engineering challenges of a 3.1-mile crossing and differing foundation conditions. Fast forward 15 years and a brilliant engineering mind would lead the way to complete the once-impossible task. Still, no Act of Congress could make the structure last forever.  Replacement was inevitable. The Tappan Zee Bridge served long and well and in the face of considerable challenges.

Rise of the Rush Hour

According to a local account, the first two hours of the bridge’s operation on December 15, 1955, saw 2,162 cars cross the span. The following year, the bridge would get its official name — Tappan Zee Bridge — and daily bridge traffic would number about 18,000 vehicles a day. Growth was in full swing on both sides of the Hudson, made possible by and in turn stimulating a dramatic increase in automobile use. By 1960, daily traffic rose to 29,000 cars and by 1970, it had more than doubled to 66,000. Spurred by economic development — and opportunity — in both Rockland and Westchester and beyond, traffic continued growing, passing 112,000 vehicles per day in 1990, then 134,000 just 10 years later. By 2010, the daily average exceeded a staggering 140,000. Major changes were now a necessity.

A bridge once expected to carry no more than 100,000 vehicles a day was now demonstrably ill-equipped to serve the amount of traffic making the daily trek over the Hudson. The bridge originally offered six lanes. In 1987, in an effort to relieve traffic congestion, the Thruway Authority converted the bridge’s center median into a seventh lane, making the lanes narrower.

The extra lane helped for a short time, but the traffic continued to rise. In 1992, the bridge introduced a movable barrier known as “the Zipper” that allowed traffic in the center lane to be redirected during peak travel times. At that time, nearly 20,000 cars on average crowded onto the bridge during a typical slow-motion peak period drive.

Bridge Fatigue

While traffic was often at a standstill on the bridge, the need for repairs never seemed to stop. The bridge had been in use for only five years before maintenance crews were busy on repairs and alterations: the concrete deck needed to be replaced because road salt caused deterioration; and then the bridge’s open drainage system had to be closed to prevent that salt from flowing onto and damaging the steel supports. A steel guide rail was added to the center median for safety but was later removed to make way for a new lane. By the 2000s, punch-through — holes in the bridge deck — were commonplace, eventually leading to the Thruway Authority to spend hundreds of millions of dollars to install precast deck panels.  In 1999, New York Governor George S. Pataki announced that the Thruway Authority was considering plans to replace the Tappan Zee Bridge.

Infrastructure Renewal

A thorough analysis of rehabilitation and replacement alternatives for the Tappan Zee Bridge continued over nearly a decade. Even before these had begun, inspections had revealed that some bridge components were nearing the end of their structural lives. The design and construction of the bridge did not permit widening or adding to the existing lanes, and the absence of breakdown lanes was a significant concern, in part because when an accident happened, traffic had to flow around it, which only added to the already serious congestion.

By 2009, the bridge was found to fall short of 21st century requirements for seismic and wind events. In the end, the evidence was unequivocal: replacement rather than repair would be more cost-effective, safer for drivers and better for the environment. In 2012, a cable-stayed replacement for the Tappan Zee was selected, and construction began two years later. But that was not the end of the Tappan Zee. During demolition, much of the old bridge was recycled, or reused for infrastructure projects and the creation of marine habitats off Long Island.

New and Improved

A striking example of innovative infrastructure renewal, the Governor Mario M. Cuomo Bridge is designed to last for more than 100 years without needing any major structural maintenance. The twin-span crossing carries goods, services and commuters through one of the nation’s most important corridors. Featuring dedicated bus lanes and a shared path for bicyclists and pedestrians, the bridge also was built with the capacity to accommodate commuter rail between its two spans in the future.