Gregorson No.1
Key Takeaway
Gregorson No.1 is classified as significant hazard in South Dakota. It was completed in 1973 and is 53 years old. Its primary use is fire protection. Significant hazard means failure could cause economic or environmental damage. Learn more.
Physical Details
| Dam Height | 34 ft (taller than 93.1% in SD) |
| Dam Length | 450 ft |
| Dam Type | Earth |
| Max Storage | 163 acre-ft |
| Normal Storage | 93 acre-ft |
| Max Discharge | 2,100 cfs |
| Year Completed | 1973 (53 years old) |
| NID ID | SD01379 |
Safety Information
No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities.
Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?
Ownership
MILDRED CLINE
Private
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Low Hazard 18 ftFrequently Asked Questions
What is the hazard classification of Gregorson No.1?
Gregorson No.1 is classified as Significant Hazard. No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.
Who owns and operates Gregorson No.1?
Gregorson No.1 is owned by MILDRED CLINE (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Gregorson No.1 built?
Gregorson No.1 was completed in 1973, making it 53 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 Gregorson No.1?
Gregorson 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 Gregorson No.1?
Gregorson No.1 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.