An autopsy revealed Simmons drowned.
A spokesman for the Fire Department of New York said Simmons was a 17-year-veteran who had worked at Ladder Company 111 in Brooklyn for the past 15 years.
A wake will be held Saturday and Sunday at Branch Funeral Home in Smithtown. A funeral Mass will be said Monday at Holy Cross Roman Catholic Church in Nesconset.
Simmons leaves a wife and three sons.
Simmons was described by a colleague as a "premier firefighter."
Simmons' family, who had been vacationing at the 191-square-mile lake, accompanied his body from Nevada to Kennedy Airport Thursday night, where his flag-draped coffin was met by an FDNY honor guard and several Port Authority Police officers who saluted as it passed.