Main Mill Dam

SARANAC RIVER· Clinton, New York· Built 1881· Concrete· 25 ft tall
High Hazard Hydroelectric Private

Key Takeaway

Main Mill Dam is classified as high hazard in New York. It was completed in 1881 and is 145 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 25 ft (taller than 69.7% in NY)
Dam Length715 ft
Dam TypeConcrete
Max Storage920 acre-ft
Normal Storage830 acre-ft
Surface Area84 acres
Drainage Area608 sq mi
Max Discharge15,820 cfs
Year Completed1881 (145 years old)
NID IDNY00262

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: September 18, 2020
State Regulated: Yes
Regulatory Agency: NYS DEC

Ownership

IMPERIAL INDUSTRIAL PARK;NYS DEC - DIVISION OF FISH AND WILDLIFE

Private

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Main Mill Dam?

Main Mill 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 Main Mill Dam?

Main Mill Dam is owned by IMPERIAL INDUSTRIAL PARK;NYS DEC - DIVISION OF FISH AND WILDLIFE (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Main Mill Dam built?

Main Mill Dam was completed in 1881, making it 145 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 Main Mill Dam?

Main Mill Dam 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 Main Mill Dam?

Main Mill Dam has a dam height of 25 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 Main Mill Dam last inspected?

Main Mill Dam was last inspected on September 18, 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.