Otisco Lake is the most easterly of the eleven Finger Lakes. It lies wholly within Onondaga county near the city of Syracuse. Otisco Lake is seventh in size among the Finger Lakes. Otisco Lake is divided into two distinct basins by a causeway at the south end. Part of Otisco Lake is man-made, due to raising the water level by damming the outlet into Nine Mile Creek. The dam initially was constructed to provide a water reservoir for the Erie Canal; the water level was raised nine feet at the time. Subsequently the dam was rebuilt, raising the level an additional four feet. The natural part of the lake, closer to the southern end, is the deepest. The southern smaller basin is shallow and extremely turbid which contrasts sharply with the relatively clear water of the main lake.

Otisco Lake, looking south through The Narrows.

Physical Features

Elevation: 787 feet
Area: 2,200 acres
Length: 5.4 miles
Maximum Width: .75 miles
Maximum Depth: 76 feet

Sources:
New York State DEC: Otisco Lake
Wikipedia