Seymour Reservoir #4 Dam Reservoir Report

Last Updated: December 5, 2025

Seymour Reservoir #4 Dam, located in Oxford, Connecticut, was completed in 1951 to serve as a crucial water supply source for the state.


°F

°F

mph

Wind

%

Humidity

Summary

This masonry dam stands at a height of 28 feet and has a length of 425 feet, providing a storage capacity of 725 acre-feet. With a normal storage level of 558 acre-feet, the dam plays a significant role in managing water resources in the region.

The dam is regulated by the Connecticut Department of Energy and Environmental Protection (DEEP) and undergoes regular inspections to ensure its structural integrity. The condition assessment conducted in 2015 rated the dam as fair, with a significant hazard potential. Despite its age, the dam continues to meet the water supply needs of the area and has a maximum discharge capacity of 260 cubic feet per second.

Water resource and climate enthusiasts can appreciate the engineering feat behind Seymour Reservoir #4 Dam, which not only provides vital water storage but also contributes to flood control and water management efforts in the region. As a state-owned structure, the dam stands as a testament to Connecticut's commitment to ensuring a sustainable and reliable water supply for its residents.

Year Completed

1951

Dam Length

425

Dam Height

28

River Or Stream

UNNAMED

Primary Dam Type

Masonry

Surface Area

40

Drainage Area

0.55

Nid Storage

725

Hazard Potential

Significant

Nid Height

28
       
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.