Riverdale Dam

PISCATAQUOG RIVER· Hillsborough, New Hampshire· Concrete· 10 ft tall
Low Hazard Flood Risk Reduction Federal Government

Key Takeaway

Riverdale Dam is classified as low hazard in New Hampshire. Its primary use is flood risk reduction.

Physical Details

Dam Height 10 ft (taller than 16% in NH)
Dam Length90 ft
Dam TypeConcrete
Max Storage153 acre-ft
Normal Storage87 acre-ft
Surface Area33 acres
Drainage Area47 sq mi
NID IDNH01103

Safety Information

Low Hazard

No probable loss of human life and low economic/environmental losses expected.

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

Emergency Action Plan: No
Last Inspection: October 25, 2011
State Regulated: Yes
Regulatory Agency: NH DES

Ownership

US ARMY CORP OF ENGINEERS

Federal Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Riverdale Dam?

Riverdale Dam is classified as Low Hazard. No probable loss of human life and low economic/environmental losses expected. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Riverdale Dam?

Riverdale Dam is owned by US ARMY CORP OF ENGINEERS (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

What is the primary purpose of Riverdale Dam?

Riverdale Dam 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 Riverdale Dam?

Riverdale Dam has a dam height of 10 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 Riverdale Dam last inspected?

Riverdale Dam was last inspected on October 25, 2011. 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.