Niantic is a census-designated place and village in the town of East Lyme, Connecticut in the United States. The population was 3,114 at the 2010 census. It is located on Long Island Sound, the Millstone Nuclear Power Plant in nearby Waterford is visible on the bay's eastern horizon line, Rocky Neck State Park is also located in the area. Niantic was once famous for its Niantic River scallops, but the scallop population has been in decline for a number of years.