Triple Seven No.1
Key Takeaway
Triple Seven No.1 is classified as low hazard in South Dakota. It was completed in 1947 and is 79 years old. Its primary use is fire protection.
Physical Details
| Dam Height | 18 ft (taller than 24.1% in SD) |
| Dam Length | 900 ft |
| Dam Type | Earth |
| Max Storage | 115 acre-ft |
| Normal Storage | 67 acre-ft |
| Max Discharge | 2,835 cfs |
| Year Completed | 1947 (79 years old) |
| NID ID | SD01377 |
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
HILLENBRAND INDUSTRIES
Private
Nearby Dams
Triple 7 Ranch Dam
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Low Hazard 32 ftBrophy Big Dam
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Low Hazard 28 ftTriple Seven No.2
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Low Hazard 23 ftWilson Ranch Dam
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Low Hazard 24 ftHarrison No.1
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Low Hazard 23 ftRasmussen No.1
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Significant Hazard 30 ftRay E. Smith Dam
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Low Hazard 18 ftSmith No.1
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Significant Hazard 28 ftFrequently Asked Questions
What is the hazard classification of Triple Seven No.1?
Triple Seven No.1 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 Triple Seven No.1?
Triple Seven No.1 is owned by HILLENBRAND INDUSTRIES (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Triple Seven No.1 built?
Triple Seven No.1 was completed in 1947, making it 79 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 Triple Seven No.1?
Triple Seven No.1 serves the following purposes: Fire Protection, Stock, Or Small Fish Pond. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Triple Seven No.1?
Triple Seven No.1 has a dam height of 18 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.