J B Long and Company #3
Key Takeaway
J B Long and Company #3 is classified as low hazard in Montana. It was completed in 1950 and is 76 years old. Its primary use is irrigation.
Physical Details
| Dam Height | 34 ft (taller than 92% in MT) |
| Dam Length | 530 ft |
| Dam Type | Earth |
| Max Storage | 62 acre-ft |
| Normal Storage | 38 acre-ft |
| Year Completed | 1950 (76 years old) |
| NID ID | MT03289 |
Safety Information
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?
Ownership
STATE OF MONTANA, D.N.R.C., T.L.M.D.
State Government
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Low Hazard 18 ftFrequently Asked Questions
What is the hazard classification of J B Long and Company #3?
J B Long and Company #3 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 J B Long and Company #3?
J B Long and Company #3 is owned by STATE OF MONTANA, D.N.R.C., T.L.M.D. (State Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was J B Long and Company #3 built?
J B Long and Company #3 was completed in 1950, making it 76 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 J B Long and Company #3?
J B Long and Company #3 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 J B Long and Company #3?
J B Long and Company #3 has a dam height of 34 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.