Eureka Reservoir Dam is an earth dam located in Teton County, Montana, built in 1936. It carries a High hazard potential classification and has a poor condition assessment.
Dam profile
NID height · 32 ft32 ft tall and 1,700 ft long, taller than 74% of U.S. dams with a recorded height. Height is drawn to scale against a two-story house, about 25 ft; the profile is a generic embankment section and the water level is illustrative.
About Eureka Reservoir Dam
The primary purpose of Eureka Reservoir Dam is irrigation. The dam stores and diverts water for agricultural irrigation, supporting farming operations in the surrounding area. The dam is owned by Teton Coop. Canal Co (private). It impounds the Teton River Offstream near Choteau.
The dam stands 32 feet tall and stretches 1,700 feet across, creates a reservoir covering 390 acres, has a maximum storage capacity of 6,800 acre-feet, and collects water from a drainage area of 1 square miles. Completed in 1936, the structure is well-established, with more than 75 years of service.
This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. Its condition is rated poor, meaning the dam has recognized safety deficiencies that require remediation to address risks. An emergency action plan is in place for this dam. The most recent inspection on record was 10/04/2023.
Living Downstream
If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The Montana dam safety program can provide more specific information about emergency planning for this structure.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | Montana |
| County | Teton |
| Nearest City | Choteau |
| River/Stream | Teton River Offstream |
| Coordinates | 47.87840, -112.31780 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 32 ft |
| Dam Height | 32 ft |
| Dam Length | 1,700 ft |
| Year Completed | 1936 (90 years old) |
Storage & Hydraulics
| NID Storage | 6,800 acre-ft |
| Max Storage | 6,800 acre-ft |
| Normal Storage | 5,500 acre-ft |
| Surface Area | 390 acres |
| Drainage Area | 1 sq mi |
| Max Discharge | 4,400 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Irrigation |
| Owner | Teton Coop. Canal Co |
| Owner Type | Private |
| Hazard Classification | High |
| Condition Assessment | Poor |
| Last Inspection | 10/04/2023 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | MT01354 |
| Federal ID | MT01354 |
| More Info | State Dam Safety Program |