Upper Kohanza Lake Dam

KOHANZA BROOK· Fairfield, Connecticut· Built 1866· Earth· 30 ft tall
High Hazard Water Supply Local Government

Key Takeaway

Upper Kohanza Lake Dam is classified as high hazard in Connecticut. It was completed in 1866 and is 160 years old. Its primary use is water supply. High hazard means loss of life is likely if the dam fails — it does not indicate the dam's current condition. Learn more.

Physical Details

Dam Height 30 ft (taller than 87.9% in CT)
Dam Length650 ft
Dam TypeEarth
Normal Storage31 acre-ft
Surface Area29 acres
Drainage Area0 sq mi
Max Discharge525 cfs
Year Completed1866 (160 years old)
NID IDCT00062

Safety Information

High Hazard

Loss of human life is likely if the dam fails.

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

Emergency Action Plan: Yes
Last Inspection: October 22, 2020
State Regulated: Yes
Regulatory Agency: DEEP

Ownership

City of Danbury

Local Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Upper Kohanza Lake Dam?

Upper Kohanza Lake Dam is classified as High Hazard. Loss of human life is likely if the dam fails. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Upper Kohanza Lake Dam?

Upper Kohanza Lake Dam is owned by City of Danbury (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Upper Kohanza Lake Dam built?

Upper Kohanza Lake Dam was completed in 1866, making it 160 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 Upper Kohanza Lake Dam?

Upper Kohanza Lake Dam serves the following purposes: Water Supply. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Upper Kohanza Lake Dam?

Upper Kohanza Lake Dam has a dam height of 30 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 Upper Kohanza Lake Dam last inspected?

Upper Kohanza Lake Dam was last inspected on October 22, 2020. 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.