Quonnipaug Lake Dam Reservoir Report

Last Updated: December 5, 2025

Quonnipaug Lake Dam, located in Guilford, Connecticut, stands as a testament to the importance of water resource management for recreation purposes.


°F

°F

mph

Wind

%

Humidity

Summary

Built in 1850, this masonry dam spans 110 feet in length and reaches a height of 5 feet, holding a storage capacity of 336 acre-feet. Situated on the West River, this dam not only provides a serene recreational spot for visitors but also plays a crucial role in regulating water levels and ensuring the safety of surrounding areas.

Despite its historical significance and primary purpose for recreation, Quonnipaug Lake Dam faces challenges in terms of its condition assessment. With a poor rating and significant hazard potential, it highlights the need for ongoing maintenance and monitoring to uphold safety standards. The dam's last inspection in March 2020 revealed these concerns, prompting a closer look at potential risk management measures and emergency preparedness to safeguard the local community and the environment.

As climate change continues to impact water resources and infrastructure, the importance of proactive measures for dam safety cannot be overstated. With Quonnipaug Lake Dam's location in a region represented by Rosa L. DeLauro in the US Congress, collaboration among local, state, and federal agencies is essential for ensuring the resilience and sustainability of this vital water resource. By prioritizing regular inspections, maintenance, and risk assessments, Quonnipaug Lake Dam can continue to serve as a beloved recreational spot while upholding its responsibility to protect the surrounding ecosystem and communities.

Year Completed

1850

Dam Length

110

Dam Height

5

River Or Stream

WEST RIVER

Primary Dam Type

Masonry

Surface Area

111.6

Drainage Area

2.63

Nid Storage

336

Hazard Potential

Significant

Nid Height

5
       
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.