Waterville is a city in Kennebec County, Maine, United States, on the west bank of the Kennebec River. A college town, the city is home to Colby College, a NESCAC college, and Thomas College. As of the 2020 census the population was 15,828. Along with Augusta, Waterville is one of the principal cities of the Augusta-Waterville, ME Micropolitan Statistical Area.