Flagpole Pond Dam Reservoir Report

Last Updated: December 18, 2025

Flagpole Pond Dam, located in Boscawen, New Hampshire, is a privately owned structure that serves primarily for recreational purposes.


°F

°F

mph

Wind

%

Humidity

Summary

Completed in 1967, this earth dam stands at a height of 21 feet and spans 480 feet in length, with a maximum storage capacity of 490 acre-feet. Situated on the Contoocook River, the dam has a low hazard potential and is currently rated as not assessed in terms of condition.

The Flagpole Pond Dam is under the jurisdiction of the New Hampshire Department of Environmental Services Dam Bureau, which regulates its operation, inspection, and enforcement. Despite its uncontrolled spillway type, the dam poses a moderate risk and is inspected every six years to ensure its safety and integrity. With a normal storage capacity of 280 acre-feet and a drainage area of 0.43 square miles, this dam provides a vital recreational resource while also being mindful of potential risks and management measures.

Water resource and climate enthusiasts will appreciate the strategic location of Flagpole Pond Dam in Merrimack County, New Hampshire, as it not only contributes to local recreational activities but also serves as a vital element in the region's water management infrastructure. With its historical significance dating back to the late 1960s, this dam continues to play a crucial role in balancing water storage and discharge requirements, all while maintaining a moderate level of risk and adhering to regulatory standards set by the state.

Year Completed

1967

Dam Length

480

Dam Height

21

River Or Stream

TR CONTOOCOOK RIVER

Primary Dam Type

Earth

Surface Area

67

Drainage Area

0.43

Nid Storage

490

Hazard Potential

Low

Foundations

Unlisted/Unknown

Nid Height

21
       
Seasonal Comparison

Weather Forecast

Dam Data Reference

Condition Assessment

Satisfactory
No existing or potential dam safety deficiencies are recognized. Acceptable performance is expected under all loading conditions (static, hydrologic, seismic) in accordance with the minimum applicable state or federal regulatory criteria or tolerable risk guidelines.
Fair
No existing dam safety deficiencies are recognized for normal operating conditions. Rare or extreme hydrologic and/or seismic events may result in a dam safety deficiency. Risk may be in the range to take further action. Note: Rare or extreme event is defined by the regulatory agency based on their minimum
Poor A dam safety deficiency is recognized for normal operating conditions which may realistically occur. Remedial action is necessary. POOR may also be used when uncertainties exist as to critical analysis parameters which identify a potential dam safety deficiency. Investigations and studies are necessary.
Unsatisfactory
A dam safety deficiency is recognized that requires immediate or emergency remedial action for problem resolution.
Not Rated
The dam has not been inspected, is not under state or federal jurisdiction, or has been inspected but, for whatever reason, has not been rated.
Not Available
Dams for which the condition assessment is restricted to approved government users.

Hazard Potential Classification

High
Dams assigned the high hazard potential classification are those where failure or mis-operation will probably cause loss of human life.
Significant
Dams assigned the significant hazard potential classification are those dams where failure or mis-operation results in no probable loss of human life but can cause economic loss, environment damage, disruption of lifeline facilities, or impact other concerns. Significant hazard potential classification dams are often located in predominantly rural or agricultural areas but could be in areas with population and significant infrastructure.
Low
Dams assigned the low hazard potential classification are those where failure or mis-operation results in no probable loss of human life and low economic and/or environmental losses. Losses are principally limited to the owner's property.
Undetermined
Dams for which a downstream hazard potential has not been designated or is not provided.
Not Available
Dams for which the downstream hazard potential is restricted to approved government users.