Waterville is a city in Lucas County, Ohio, United States, along the Maumee River. A suburb of Toledo, the population was 6,003 at the …Waterville is a city in Lucas County, Ohio, United States, along the Maumee River. A suburb of Toledo, the population was 6,003 at the 2020 census. Waterville was platted in 1830 by settler John Pray on the west bank of the upper Maumee River opposite what was then known as Pray's Falls, a rapids on that stream. A post office called Waterville has been in operation since 1828.