Officials blame cold winter for metal and concrete that smashed onto Manhattan expressway

Water and road salt leaked into expansion joints of a decked area above the Trans-Manhattan Expressway near the George Washington Bridge. Extended periods of extremely cold temperatures and significant snowfall produced freeze-thaw cycles that further corroded concrete. Two debris falls occurred on May 7 and May 13, with a metal piece falling on May 7 and concrete falling on May 13 and landing on a car. The May 13 driver was hospitalized with injuries. The area had been inspected last year without an immediate health and safety problem identified. Crews tested concrete around other expansion joints, removed weak spots, and installed wire netting above the roadway to catch future debris.

"Port Authority Executive Director Kathryn Garcia said water and salt leaked into the joints of a decked area above the roadway leading up to the George Washington Bridge. She said some of the infrastructure deteriorated after months of freezing and thawing as the city emerged from its coldest winter in more than a decade. Two large pieces of debris plummeted from the bridge's approach on May 7 and May 13, with debris falling from the roadway's ceiling in both incidents."

"Garcia said the debris that fell from the roadway's ceiling on May 7 in a caught-on-camera episode was a piece of metal. Port Authority officials previously said it appeared to "consist primarily of dust and light material." Garcia said concrete fell from the ceiling on May 13 and landed on a car. The driver in that incident was hospitalized with injuries."

"But Garcia told reporters Thursday that he Port Authority now determined both debris falls were caused by water and road salt seeping in through expansion joints - tooth-like seams that allow the bridge and deck to expand and contract in the heat and cold. "This winter we had extended periods of extremely cold temperatures and significant snowfall," Garcia said. That freeze-thaw cycle contributed to "further corroding of some of the concrete.""

"Garcia said the area was inspected last year, but investigators "did not identify an immediate health and safety problem." Crews have now tested the concrete around other expansion joints and jackhammered away other weak spots, Garcia said. The Port Authority has also installed wire netting above the roadway to catch any future debris. "This is not, like, fishnet," Garcia said."

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