Ryley S. Buononato, a resident of Amenia in Dutchess County, jumped around 2:45 p.m. on Monday, Dec. 16, according to an MTA spokesman.
A motorist traveling on Otterville Road in Cornwall, where the viaduct is located, reported hearing an abnormal sound, the MTA said. The driver pulled the car over and found a white female near the roadway.
The MTA Police were notified by local police and assumed the lead on the investigation.
Buononato was transported to Montefiore St. Luke's Cornwall Hospital in Newburgh, where she was pronounced dead.
No criminality is suspected, MTA said.
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