Jappe

EIGHTMILE COULEE· Chouteau, Montana· Built 1956· Earth· 36 ft tall
Low Hazard Irrigation Private

Key Takeaway

Jappe is classified as low hazard in Montana. It was completed in 1956 and is 70 years old. Its primary use is irrigation.

Physical Details

Dam Height 36 ft (taller than 93.8% in MT)
Dam Length600 ft
Dam TypeEarth
Max Storage500 acre-ft
Normal Storage445 acre-ft
Drainage Area7 sq mi
Max Discharge1,050 cfs
Year Completed1956 (70 years old)
NID IDMT00214

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

HENRY J DRGA

Private

Nearby Dams

Chip Dipper

Chouteau, MT

Low Hazard 20 ft

Drga Dam

Chouteau, MT

Significant Hazard 30 ft

Moes

Chouteau, MT

Low Hazard 35 ft

Tortilla

Chouteau, MT

Low Hazard 12 ft

Browns

Chouteau, MT

Low Hazard 47 ft

Pn Grazing Association #1

Fergus, MT

Low Hazard 15 ft

Delilah

Chouteau, MT

Significant Hazard 10 ft

Pluto

Chouteau, MT

Low Hazard 16 ft

Frequently Asked Questions

What is the hazard classification of Jappe?

Jappe 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 Jappe?

Jappe is owned by HENRY J DRGA (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Jappe built?

Jappe was completed in 1956, making it 70 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 Jappe?

Jappe 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 Jappe?

Jappe has a dam height of 36 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.