Tonawanda (formally City of Tonawanda, from Tuscarora Tahnawá•teh in Tuscarora) is a city in Erie County, New York, United States. The population was 16,136 at the 2000 census. It is located at the northern edge of Erie County, south across the Erie Canal from North Tonawanda, and north of Buffalo, New York. It is part of the Buffalo-Niagara Falls metropolitan area.