It happened Sunday night, Nov. 10 just after 9 p.m. in Mattituck in the waters of Great Peconic Bay off Old Salt Road.
The 39-foot Cobalt was leaving the bay and entering a creek when it hit a barrier, resulting in the death of Kelley Blanchard, 27, of Riverhead, police said.
The boat's operator, Frank DiStefano, 48, of East Northport, Megan Blanchard, 29, of New Suffolk, and Nick Soulas, 41, of Jamesport, were all seriously injured.
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