Tunnel Dam Hydro Station

QUINEBAUG RIVER· New London, Connecticut· Built 1906· Concrete· 32 ft tall
Significant Hazard Hydroelectric Public Utility

Key Takeaway

Tunnel Dam Hydro Station is classified as significant hazard in Connecticut. It was completed in 1906 and is 120 years old. Its primary use is hydroelectric. Significant hazard means failure could cause economic or environmental damage. Learn more.

Physical Details

Dam Height 32 ft (taller than 89.8% in CT)
Dam Length780 ft
Dam TypeConcrete
Max Storage1.7K acre-ft
Normal Storage1.7K acre-ft
Surface Area100 acres
Drainage Area744 sq mi
Max Discharge33,940 cfs
Year Completed1906 (120 years old)
NID IDCT00637

Safety Information

Significant Hazard

No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities.

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

Emergency Action Plan: Yes
Last Inspection: July 27, 2016
State Regulated: Yes
Regulatory Agency: DEEP

Ownership

FirstLight Power Resources

Public Utility

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Tunnel Dam Hydro Station?

Tunnel Dam Hydro Station is classified as Significant Hazard. No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Tunnel Dam Hydro Station?

Tunnel Dam Hydro Station is owned by FirstLight Power Resources (Public Utility). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Tunnel Dam Hydro Station built?

Tunnel Dam Hydro Station was completed in 1906, making it 120 years old. Many U.S. dams were built between the 1930s and 1970s during a period of major infrastructure investment.

What is the primary purpose of Tunnel Dam Hydro Station?

Tunnel Dam Hydro Station serves the following purposes: Hydroelectric. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Tunnel Dam Hydro Station?

Tunnel Dam Hydro Station has a dam height of 32 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 Tunnel Dam Hydro Station last inspected?

Tunnel Dam Hydro Station was last inspected on July 27, 2016. 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.