Lark Detention Dam
Lark Detention Dam is a gravity dam located in Phillips County, Montana, built in 1968. It carries a Low hazard potential classification and has a fair condition assessment.
About Lark Detention Dam
The primary purpose of Lark Detention Dam is flood risk reduction. The dam is designed to control downstream flooding by temporarily storing excess water during storms and releasing it at a controlled rate. The dam is owned by Doi Blm (federal). It impounds the Rock Ck./missouri River near Fort Peck.
The dam stands 41 feet tall and stretches 513 feet across, creates a reservoir covering 12 acres, has a maximum storage capacity of 215 acre-feet, and collects water from a drainage area of 1 square miles. Completed in 1968, the structure is well into its service life at over 50 years old.
This dam has a low hazard potential classification, meaning that failure would cause minimal damage, limited primarily to the dam owner's property, with no expected loss of life. Its condition is rated fair — the dam has minor deficiencies that are being addressed or do not pose an immediate safety threat. The most recent inspection on record was 08/15/2016.
At 41 feet, this dam is taller than 88% of dams nationwide.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | Montana |
| County | Phillips |
| Nearest City | Fort Peck |
| River/Stream | Rock Ck./missouri River |
| Coordinates | 47.74068, -108.53115 |
Physical Characteristics
| Dam Type | Gravity |
| NID Height | 41 ft |
| Dam Length | 513 ft |
| Year Completed | 1968 (58 years old) |
Storage & Hydraulics
| NID Storage | 215 acre-ft |
| Max Storage | 215 acre-ft |
| Surface Area | 12 acres |
| Drainage Area | 1 sq mi |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | DOI BLM |
| Owner Type | Federal |
| Hazard Classification | Low |
| Condition Assessment | Fair |
| Last Inspection | 08/15/2016 |
| Emergency Action Plan | Not Required |
Identifiers
| NID ID | MT00726 |
| Federal ID | MT00726 |
| More Info | State Dam Safety Program |