Although it is near the Finger Lakes region, it is not traditionally counted as one of the Finger Lakes. Onondaga Lake is a dimictic lake, meaning that the lake water completely mixes from top to bottom twice a year. The lake is 4.6 miles long and 1 mile wide making a surface area of 4.6 square miles. The maximum depth of the lake is 63 feet with an average depth of 35 feet. Its drainage basin has a surface area of 642 square kilometers, encompassing Syracuse, Onondaga County except the eastern and northern edges, the southeastern corner of Cayuga County and the Onondaga Nation Territory, and supports approximately 450,000 people.