Broadwater Dam
Broadwater Dam is a gravity dam located in Broadwater County, Montana, built in 1940. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Broadwater Dam
The primary purpose of Broadwater Dam is hydroelectric. The dam generates hydroelectric power by channeling water through turbines, converting the energy of flowing water into electricity. The dam is owned by Montana Dept Of Natural Resources & Conservation (state). It impounds the Missouri River near Toston, Mt.
The dam stands 50 feet tall and stretches 705 feet across, creates a reservoir covering 327 acres, has a maximum storage capacity of 6,460 acre-feet, and collects water from a drainage area of 14,660 square miles. Completed in 1940, 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 satisfactory, indicating no existing or potential dam safety deficiencies are recognized. An emergency action plan is in place for this dam. The most recent inspection on record was 03/25/2022.
At 50 feet, this dam is taller than 93% of dams nationwide.
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 | Broadwater |
| Nearest City | Toston, Mt |
| River/Stream | Missouri River |
| Coordinates | 46.12000, -111.40830 |
Physical Characteristics
| Dam Type | Gravity |
| NID Height | 50 ft |
| Dam Height | 24 ft |
| Dam Length | 705 ft |
| Year Completed | 1940 (86 years old) |
Storage & Hydraulics
| NID Storage | 6,460 acre-ft |
| Max Storage | 6,460 acre-ft |
| Normal Storage | 4,100 acre-ft |
| Surface Area | 327 acres |
| Drainage Area | 14,660 sq mi |
| Max Discharge | 68,900 cfs |
| Spillway Type | Controlled |
Ownership & Safety
| Purpose | Hydroelectric |
| Owner | Montana Dept of Natural Resources & Conservation |
| Owner Type | State |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 03/25/2022 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | MT00016 |
| Federal ID | MT00016 |
| More Info | State Dam Safety Program |