Big Rock Detention Dam
Montana — Valley County — WILLOW CK./MILK RIVER
Location
| State | Montana |
| County | Valley |
| River | WILLOW CK./MILK RIVER |
| Coordinates | 48.08686, -106.95780 |
Physical Characteristics
| NID Height | 13 ft |
| Dam Height | — |
| Dam Length | 1,793 ft |
| NID Storage | 265 acre-ft |
| Max Storage | 265 acre-ft |
| Surface Area | 62 acres |
Safety Classification
| Hazard Potential | Low |
| Condition Assessment | Unsatisfactory |
| EAP Status | Not Required |
| Last Inspection | November 2, 2019 |
| Inspection Frequency | 5 |
Dam Information
| Year Completed | 1961 |
| Primary Purpose | Flood Risk Reduction |
| Dam Type | Gravity |
| Owner Type | Federal |
| Owner | DOI BLM |
Location Map
About This Dam Record
Dam safety data is maintained by the Army Corps of Engineers National Inventory of Dams (NID). High-hazard dams are those where failure could cause loss of life or major property damage downstream.