Lewiston

Niagara River· Niagara, New York· Built 1963· Concrete· 155 ft tall
High Hazard Hydroelectric State Government

Key Takeaway

Lewiston is classified as high hazard in New York. It was completed in 1963 and is 63 years old. Its primary use is hydroelectric. 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 155 ft (taller than 99.5% in NY)
Dam Length975 ft
Dam TypeConcrete
Max Storage76.0K acre-ft
Drainage Area3 sq mi
Max Discharge0 cfs
Year Completed1963 (63 years old)
NID IDNY00689

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: June 29, 2022
State Regulated: No

Ownership

New York Power Authority

State Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Lewiston?

Lewiston 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 Lewiston?

Lewiston is owned by New York Power Authority (State Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Lewiston built?

Lewiston was completed in 1963, making it 63 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 Lewiston?

Lewiston 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 Lewiston?

Lewiston has a dam height of 155 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 Lewiston last inspected?

Lewiston was last inspected on June 29, 2022. 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.