Neponset River Dam - Lower Mills

NEPONSET RIVER· Suffolk, Massachusetts· Concrete· 15 ft tall
Significant Hazard Flood Risk Reduction State Government

Key Takeaway

Neponset River Dam - Lower Mills is classified as significant hazard in Massachusetts. Its primary use is flood risk reduction. Significant hazard means failure could cause economic or environmental damage. Learn more.

Physical Details

Dam Height 15 ft (taller than 48.8% in MA)
Dam Length140 ft
Dam TypeConcrete
Max Storage250 acre-ft
Normal Storage220 acre-ft
Surface Area64 acres
Drainage Area109 sq mi
NID IDMA01093

Safety Information

Significant Hazard

No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities.

Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?

Emergency Action Plan: No
Last Inspection: March 29, 2018
State Regulated: Yes
Regulatory Agency: DEPARTMENT OF CONSERVATION AND RECREATION

Ownership

DCR - DEPT. OF CONSERVATION & RECREATION

State Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Neponset River Dam - Lower Mills?

Neponset River Dam - Lower Mills is classified as Significant Hazard. No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Neponset River Dam - Lower Mills?

Neponset River Dam - Lower Mills is owned by DCR - DEPT. OF CONSERVATION & RECREATION (State Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

What is the primary purpose of Neponset River Dam - Lower Mills?

Neponset River Dam - Lower Mills serves the following purposes: Flood Risk Reduction. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Neponset River Dam - Lower Mills?

Neponset River Dam - Lower Mills has a dam height of 15 ft. Dam height is measured from the natural streambed at the downstream toe to the top of the dam, and may differ from the visible height.

When was Neponset River Dam - Lower Mills last inspected?

Neponset River Dam - Lower Mills was last inspected on March 29, 2018. Inspection dates indicate when a formal review occurred, not the results of that inspection.

Data from the National Inventory of Dams (NID) maintained by the US Army Corps of Engineers. Dam conditions may have changed since the last update. This site is not affiliated with USACE. Do not use for emergency planning — contact your local dam safety program.