The
Tappan Zee river crossing was named by 17th century
Dutch settlers. The Tappan Zee Bridge is the only crossing of the Hudson between
Westchester and
Rockland counties. The
original Tappan Zee Bridge was a
cantilever bridge built from 1952 to 1955. The bridge was long and spanned the Hudson at its second-widest point. It was the longest bridge in New York State, at a length of including approaches. Built immediately after the
Korean War, the bridge had a low
construction budget of only $81 million and a designed life-span of only 50 years. During its first decade, the bridge carried fewer than 40,000 vehicles per day.
Planning By the start of the 21st century, the old Tappan Zee Bridge was "decaying" and "overburdened". The
collapse of Minnesota's I-35W Mississippi River bridge in 2007 raised worries about the Tappan Zee Bridge's structural integrity. These concerns, together with traffic overcapacity and increased maintenance costs, escalated the serious discussions already ongoing about replacing the Tappan Zee with a
tunnel or a new bridge. Six options were identified and submitted for project study and environmental review. The
Federal Highway Administration issued a report in October 2011 designating the Tappan Zee's replacement to be a dual-
span twin bridge. The new bridge was to be built a few yards to the north of the existing bridge, connecting to the existing
highway approaches of the New York State Thruway (I-87/I-287) on both river banks. The
New York State Thruway Authority (NYSTA) requested design proposals from four companies in 2012 and eventually received three project proposals. The authority awarded a $3.142 billion contract to Tappan Zee Constructors (TZC), whose proposal was not only the least expensive but also promised the shortest construction timeline and included plans to minimize environmental impact. However, the state passed legislation freezing the toll on the bridge at $5 through 2020 in its 2016 legislative session. The new Tappan Zee Bridge was proposed to include four vehicle lanes on each span, for a total of eight lanes, as well as a shared-use bicycle and pedestrian path. Like its predecessor, the new Tappan Zee Bridge is to be administered by the NYSTA. The authority is the project co-sponsor, along with the state
Department of Transportation. The
United States Department of Transportation approved the plan on September 25, 2012. The approval process took fewer than 10 months as opposed to the traditional multi-year process as a result of being placed on a "fast track" for approval by the
Obama administration. On December 17, 2012, New York state officials dropped their proposal for a 45 percent increase on the State Thruway toll for trucks, while advancing a $3.14 billion project to replace the bridge. The project was funded through a
public-private partnership. Construction began as scheduled in October 2013, with completion targeted for 2017. TZC, the contractor, was composed of several design, engineering, and construction firms including
Fluor Corporation,
American Bridge Company, Granite Construction Northeast and Traylor Bros. The
Left Coast Lifter was used to install groups of pre-assembled girders one full span at a time. The contractors were obliged to finish the bridge by 2018, after which the state would fine the contractors around $100,000 per day. By the end of 2013, General Electric had completed four seasons of dredging to remove contaminants from the river bottom. Approximately 70 percent of the sediments targeted for dredging were removed (totaling more than of sediment). On July 19, 2016, a crane used for the construction of the bridge collapsed onto the existing older bridge. Five people were injured, including three drivers and two bridge workers; no one was killed or critically injured.
Completion The project timeline originally indicated that the old bridge would be closed in 2016 and that the demolition of the old bridge would begin in February 2017. The new northbound/westbound span opened on August 26, 2017. Southbound/eastbound traffic remained on the existing span until October 6, 2017, when it was shifted to the new northbound/westbound span to allow for the completion of the new southbound/eastbound span. The northbound/westbound span of the new Tappan Zee Bridge temporarily carried four lanes in each direction until the new southbound/eastbound span was completed. After some delays, the project was later expected to be completed by June 15, 2018, However, the scheduled opening was later pushed back to mid-September. The new southbound/eastbound span was supposed to open to traffic on September 8, 2018. An opening ceremony was held on that date, but the traffic shift itself was delayed when a piece of the old bridge came loose on September 7 while being demolished. The opening of the eastbound span, which was away from the old bridge, was delayed until the old bridge could be stabilized. After the old bridge was stabilized, all lanes were opened on September 11, 2018. The demolition of the old bridge started in November 2017 with the removal of the first steel section from the Rockland County approach. The work continued to April 2018 including the removal of the truss sections. In May 2018, the 10-million-pound main span was removed, leaving only the east and west approaches. The original plan was to complete the remaining demolition by taking down spans piece by piece in order to minimize the environmental impacts. However, when the instability of the eastern span was discovered in September 2018, it was decided to destroy it outright.
Structural problems Reports of a coverup of structural problems emerged in December 2018. Dozens of bolts holding the steel girders together had failed, and some bolts broke more than a year after they had been tightened into the plates that hold the girders together. A presentation by a whistleblower included allegations that the bolts had broken due to
hydrogen embrittlement, which weakened the metal. The number of failed bolts was abnormally high for a project the size of this bridge. Engineering experts warned that the structural problems could compound, causing the girders to fall and the bridge to collapse. The issue was known as early as February 2016, when New York state officials had begun testing some bolts for breaks. Following this, U.S. Representative
Mondaire Jones, whose district encompasses the bridge, and all Republican members of the
New York State Assembly requested that the
United States Department of Transportation investigate the allegations of structural deficiencies. In response, the
Federal Highway Administration issued a statement claiming it had "no safety concerns" with either of the Tappan Zee Bridge's spans. In a lawsuit filed that month, a whistleblower claimed that TZC had knowingly delivered many defective high-strength bolts and taken measures to hide evidence of the defects. The NYSTA sued TZC in August 2024, claiming that around 61 of the 192 cables had been improperly installed and needed to be repaired. == Description ==