The opening of a $4bn (£3.1bn) New York span bridge has been delayed due to concerns that its predecessor could collapse.
The opening of the second span of the Mario M. Cuomo Bridge has been delayed after officials confirmed that its predecessor, the old Tappan Zee Bridge which runs parallel to the new bridge, had “became destabilized and threatened to fall”.
Pending a further investigation into the structure’s safety, the bridge is now mooted to open later this week.
New York state thruway authority chief executive Matthew Driscoll said that “the Tappan Zee was being disassembled when the potentially dangerous situation developed” and a piece of the old bridge became “destabilized”.
He added that engineers from the Tappan Zee Constructors consortium – made up from firms including Fluor, American Bridge, Granite, and Traylor Bros – heard a “loud pop” coming from the structure as it was being dissembled.
Initial reports suggest that there are problems with the joints as well as a damaged and rusted piece of the old bridge.
Officials feat that a potential collapse could cause the old bridge to fall and damage the new eastbound span.
The first span of the new bridge opened last year after decades of political posturing over whether to repair the old Tappan Zee bridge or build a new one.
The new bridge 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.
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