Lower Mill Pond, 50.4 acres, is located south of MA-6A, near the intersection of Setucket and Stony Brook Road.

The shoreline is moderately developed. A historic grist mill is operated at the dam site, and a town park has been developed incorporating the mill and herring run.

The pond is recharged by groundwater flow from the south and by a surface outlet from Upper Mill Pond. The pond is dammed at its northern tip. It discharges to a herring run (Stony Brook).