Squam Lake Reservoir Report

Last Updated: December 16, 2025

Squam Lake in New Hampshire is a captivating water resource for climate and nature enthusiasts.


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Summary

This picturesque lake is regulated by the NHDES Dam Bureau and is under state jurisdiction, ensuring its protection and conservation. With a primary purpose of hydroelectric power generation, Squam Lake also serves other functions such as fire protection, stock, and recreation.

The dam on Squam Lake was completed in 1856 and stands at a height of 16.5 feet, with a storage capacity of 39,600 acre-feet and a surface area of 7,173 acres. The controlled spillway and three slide gates help manage water levels and mitigate potential hazards. The lake's significant hazard potential underscores the importance of regular inspections and emergency preparedness measures.

With its rich history, diverse purposes, and breathtaking natural beauty, Squam Lake is a valuable water resource deserving of attention and stewardship. From its hydroelectric capabilities to its recreational opportunities, this tranquil lake in Grafton, New Hampshire, offers a blend of functionality and scenic wonder for all to enjoy and protect.

Year Completed

1856

Dam Length

200

Dam Height

16.5

River Or Stream

Squam River

Surface Area

7173

Drainage Area

58

Nid Storage

39600

Outlet Gates

Slide (sluice gate) - 3

Hazard Potential

Significant

Nid Height

17
       
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.