Onota Lake is a 617-acre lake located entirely within the City of Pittsfield and is owned and managed by the City of Pittsfield. Many recreational opportunities are provided by the lake and are enjoyed by area residents as well as those visiting the Berkshires. However, like many area lakes, Onota Lake is threatened. While these problems are not unusual, atypical, or severe, they do require attention.

The watershed of Onota Lake is approximately 6,345 acres in area. Onota Lake is often described as “two lakes in one” due to the minimal water exchange between the north and south basins due to the old roadway that marked the north end of the original lake prior to the building of the dam. The outlet of Onota Lake, Onota Brook, flows southeast entering the West Branch of the Housatonic River, in Pittsfield.