Thompson Island Dam

HUDSON RIVER· Saratoga, New York· Built 1910· Concrete· 15 ft tall
Low Hazard Navigation State Government

Key Takeaway

Thompson Island Dam is classified as low hazard in New York. It was completed in 1910 and is 116 years old. Its primary use is navigation.

Physical Details

Dam Height 15 ft (taller than 37.1% in NY)
Dam Length736 ft
Dam TypeConcrete
Max Storage1.0K acre-ft
Normal Storage1.0K acre-ft
Surface Area36 acres
Drainage Area3,440 sq mi
Year Completed1910 (116 years old)
NID IDNY01074

Safety Information

Low Hazard

No probable loss of human life and low economic/environmental losses expected.

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

Emergency Action Plan: No
Last Inspection: August 27, 1971
State Regulated: Yes
Regulatory Agency: NYS DEC

Ownership

New York State Canal Corporation

State Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Thompson Island Dam?

Thompson Island Dam is classified as Low Hazard. No probable loss of human life and low economic/environmental losses expected. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Thompson Island Dam?

Thompson Island Dam is owned by New York State Canal Corporation (State Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Thompson Island Dam built?

Thompson Island Dam was completed in 1910, making it 116 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 Thompson Island Dam?

Thompson Island Dam serves the following purposes: Navigation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Thompson Island Dam?

Thompson Island Dam has a dam height of 15 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 Thompson Island Dam last inspected?

Thompson Island Dam was last inspected on August 27, 1971. 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.