Griswold No. 1
Key Takeaway
Griswold No. 1 is classified as low hazard in Wyoming. It was completed in 1954 and is 72 years old. Its primary use is fire protection.
Physical Details
| Dam Height | 25 ft (taller than 39.5% in WY) |
| Dam Length | 645 ft |
| Dam Type | Earth |
| Max Storage | 133 acre-ft |
| Normal Storage | 73 acre-ft |
| Surface Area | 10 acres |
| Drainage Area | 0 sq mi |
| Max Discharge | 0 cfs |
| Year Completed | 1954 (72 years old) |
| NID ID | WY00755 |
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
TETRAD CORPORATION
Private
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Low Hazard 20 ftFrequently Asked Questions
What is the hazard classification of Griswold No. 1?
Griswold 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 Griswold No. 1?
Griswold No. 1 is owned by TETRAD CORPORATION (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Griswold No. 1 built?
Griswold No. 1 was completed in 1954, making it 72 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 Griswold No. 1?
Griswold 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 Griswold No. 1?
Griswold No. 1 has a dam height of 25 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.
When was Griswold No. 1 last inspected?
Griswold No. 1 was last inspected on September 28, 2023. Inspection dates indicate when a formal review occurred, not the results of that inspection.