Thorn

TR-REDWATER RIVER· McCone, Montana· Built 1971· Earth· 10 ft tall
Low Hazard Irrigation Private

Key Takeaway

Thorn is classified as low hazard in Montana. It was completed in 1971 and is 55 years old. Its primary use is irrigation.

Physical Details

Dam Height 10 ft (taller than 3.7% in MT)
Dam Length250 ft
Dam TypeEarth
Max Storage92 acre-ft
Normal Storage12 acre-ft
Year Completed1971 (55 years old)
NID IDMT02702

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
State Regulated: Yes
Regulatory Agency: DNRC

Ownership

FRED A THOENY

Private

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Thorn?

Thorn 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 Thorn?

Thorn is owned by FRED A THOENY (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Thorn built?

Thorn was completed in 1971, making it 55 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 Thorn?

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

How tall is Thorn?

Thorn has a dam height of 10 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.

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.