MEC&F Expert Engineers : An inspection of span on the remaining eastern portion of the old Tappan Zee Bridge had become destabilized and could fall

Sunday, September 9, 2018

An inspection of span on the remaining eastern portion of the old Tappan Zee Bridge had become destabilized and could fall






NEW YORK, NY — 


The Coast Guard has closed the eastern half of the channel in the Hudson River near the old Tappan Zee Bridge, Saturday.

On Friday evening, engineers requested Coast Guard assistance in closing the eastern half of the main Federal navigation channel after an inspection of span on the remaining eastern portion of the old Tappan Zee Bridge had become destabilized and could fall.

The old Tappan Zee Bridge is not currently in use and is in the process of demolition.

The engineers notified watchstanders at Coast Guard Sector New York to the issue at approximately 7:45 p.m. Friday night.

Due to the uncertainty and need to ascertain the potential impact of a collapse, it was requested the Coast Guard institute an emergency safety zone. The Hudson River was then completely closed to vessel traffic at the Tappan Zee Bridge.

At 12:00 p.m. Saturday, the western half of the Federal navigation channel was opened to vessel traffic. Vessels may transit the area after checking in with the Coast Guard patrol commander enforcing the safety zone.

Coast Guard Cutter Sturgeon Bay and a response boat crew from Coast Guard Maritime Safety and Security Team – New York, are on scene to enforce the safety zone. Other agencies assisting are Rockland County Sheriff, Westchester County Sheriff, and New York Department of Environmental Conservation.

The cause of the structural failure is still under investigation.

To get the latest updates on the condition of the channel click here.

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‘Potentially Dangerous Situation’ on Tappan Zee Delays Opening of New Cuomo Bridge Span
ImageThe first segment of the new Mario M. Cuomo Bridge was opened last year. The opening of the second was delayed over concerns that a piece of its predecessor, the Tappan Zee Bridge, far left, had become destabilized.CreditCreditChang W. Lee/The New York Times


By Mihir Zaveri
Sept. 8, 2018



The opening of the second span of the Mario M. Cuomo Bridge on Saturday was delayed after a piece of its predecessor, the old Tappan Zee Bridge, which is parallel to it, became destabilized and threatened to fall, officials said.

The Tappan Zee was being disassembled when the “potentially dangerous situation developed” and a piece of the old bridge became destabilized, Matthew J. Driscoll, the executive director of the New York State Thruway Authority, said in a statement on Saturday.

Mr. Driscoll said that the Tappan Zee was being evaluated but that the new span of the Mario M. Cuomo Bridge would remain closed until the authority was “assured there is no risk to the new span.”

At around 5 p.m. on Friday, crew members disassembling the old bridge heard a “loud pop” coming from the structure, Terry Towle, the president of Tappan Zee Constructors, told reporters on Saturday evening.

There appeared to be problems with joints that could have theoretically caused the old bridge to fall toward the new eastbound span, which is 160 feet away, he said.

Engineers inspected the old bridge and it did not appear that the new span was in danger, Mr. Towle said, adding that he had no estimate on when the eastbound span would open. He said he was waiting for additional assurances from multiple engineers that the old bridge was fully stabilized.

“I’m not going to take any risk whatsoever,” he said.

Gov. Andrew M. Cuomo told reporters earlier on Saturday that contractors on Friday had discovered a damaged and rusted piece of the old bridge that could pose a potential threat to the new span.

“We want to move the traffic over as quickly as possible,” Mr. Cuomo said. “The new bridge is ready.”

The Coast Guard had closed the eastern half of the main federal navigation channel of the Hudson River on Friday after the structural issue was found.

On Saturday, the Coast Guard reopened the western part of the river to vessels that checked with the patrol commander enforcing the safety zone, but it said the eastern half remained closed because of the destabilized bridge.

Coast Guard officials did not immediately respond to a request for comment.

The problem came a day after Mr. Cuomo and other dignitaries gathered at the new bridge to celebrate the planned opening of the second span. Mr. Cuomo lauded the new bridge as a testament to “New York’s greatness” that “shows the world that we’re capable of dreaming big and delivering results for the people of this state.”

The first span of the new bridge, a $4 billion project, opened last year after decades of wrangling over whether to repair the Tappan Zee or build a new bridge.

The westbound span of the bridge had been carrying both eastbound and westbound traffic. Eastbound traffic was set to be shifted to the new span after it opened this weekend, but concerns about the stability of the old bridge delayed that shift.

The new bridge, which connects Rockland and Westchester Counties, is a two-span cable-stayed design, with the cables holding up its steel decks anchored to the tops of the angled central towers rather than to the shore.

The old Tappan Zee was closed to traffic in October and was being disassembled piece by piece. By December, each end of the bridge had been removed so that it did not connect to either bank of the Hudson River.

As the Democratic primary in New York on Thursday approaches, Mr. Cuomo’s opponents seized on the problem with the old bridge, with some suggesting that Mr. Cuomo prematurely announced the opening of the span of the new bridge. The goal had been to fully open the new bridge in 2018, and Mr. Cuomo said last month that he was looking at a mid-September completion.


“A ribbon-cutting ceremony should not have been held if the bridge span was not yet safe,” said Cynthia Nixon, the actor and activist who is challenging Mr. Cuomo in the Democratic primary.

Marcus J. Molinaro, the Dutchess County executive and Republican candidate for governor, said in a statement on Saturday that “it’s now clearer than ever that the bridge was opened to meet Governor Cuomo’s political agenda without regard for public safety.”

Stephanie Miner, the former mayor of Syracuse and an independent challenger of Mr. Cuomo, said in a statement: “What’s more important — fancy ceremonies so the governor can get good press before the primary or safety?”

Dani Lever, Mr. Cuomo’s press secretary, said in a statement: “The Mario M. Cuomo bridge is complete and ready for traffic and the action taken by TPZ Construction, given the potential issue on the old structure, was out of an abundance of caution and about public safety, not politics. Anyone trying to score political points off of it only underscores why they are unfit to serve.”

Mr. Towle said the abrupt change of plans for the new bridge was a blow for the engineers and workers who were prepared to open the new structure.

“We worked our butts off to get this eastbound span done,” he said. “The fact that it’s sitting empty waiting for traffic is somewhat of an embarrassment.”



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Tuesday, May 08, 2018


TARRYTOWN, Westchestser County (WABC) -- 


Crews have begun the delicate task of removing the superstructure of the old Tappan Zee Bridge, with special cranes lowering part of the center span that weighs 10 million pounds onto a barge.

The bridge was retired last fall when the replacement Mario M. Cuomo Bridge opened. For months, sections of roadway near the shore on either side of the Hudson River have been removed. The next phase will see demolition of the cantilever bridge, which has been cut into five sections.

"New York is leading the nation in rebuilding and reimagining our infrastructure so we can meet the demands of the fast-paced, 21st century economy," Cuomo said. "For decades, the Tappan Zee Bridge was a symbol of government incompetence and procrastination. But today's lowering of the main span of the old bridge marks the critical progress we have made. The new Mario M. Cuomo Bridge is critical to the growth and sustainability not only of the region, but of the entire state as we build a better, stronger New York."

The 2,415-foot main span of the Tappan Zee Bridge will be removed in five separate operations, the first of which began overnight on Monday. Eight hydraulic strand jacks are lowering the 4,750-ton suspended center span onto a barge to be transported offsite for further disassembly.

The steel will be cleaned and used as artificial reefs on Long Island.

The four other operations are scheduled to take place in the coming months. Barge-based cranes will remove two cantilever truss sections, while the two anchor spans will be lowered onto barges with the assistance of strand jacks. After the main span dismantling, the "I Lift NY" floating super crane will assist with the removal of the main span's steel support structures. The main span removal operation is expected to be complete by late fall.

In the meantime, construction continues on the new $4 billion, twin span bridge.

Currently, all traffic is being routed onto what what will eventually be the Rockland County-bound span. The second, Westchester County-bound crossing is scheduled to open before the end of the year.