Lake Desmet (South Dam)
Key Takeaway
Lake Desmet (South Dam) is classified as high hazard in Wyoming. It was completed in 1975 and is 51 years old. Its primary use is water supply. High hazard means loss of life is likely if the dam fails — it does not indicate the dam's current condition. Learn more.
Physical Details
| Dam Height | 80 ft (taller than 97.2% in WY) |
| Dam Length | 4,000 ft |
| Dam Type | Earth |
| Max Storage | 235.0K acre-ft |
| Normal Storage | 111.8K acre-ft |
| Surface Area | 2,653 acres |
| Drainage Area | 41 sq mi |
| Max Discharge | 8,520 cfs |
| Year Completed | 1975 (51 years old) |
| Year Modified | 2009 |
| NID ID | WY02302 |
Safety Information
Loss of human life is likely if the dam fails.
Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?
Ownership
JOHNSON COUNTY-LAKE DESMET OPERATING DEPT
Local Government
Nearby Dams
Lake Desmet (A,B,C & Spillway Dikes)
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High Hazard 80 ftTaylor No. 2
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Low Hazard 30 ftIrene
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Low Hazard 30 ftLake Desmet (North Dam)
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High Hazard 80 ftKaufmann
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Low Hazard 49 ftDump Draw
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High Hazard 42 ftBuffalo Wildlife Pond
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Low Hazard 11 ftFrequently Asked Questions
What is the hazard classification of Lake Desmet (South Dam)?
Lake Desmet (South Dam) is classified as High Hazard. Loss of human life is likely if the dam fails. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.
Who owns and operates Lake Desmet (South Dam)?
Lake Desmet (South Dam) is owned by JOHNSON COUNTY-LAKE DESMET OPERATING DEPT (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Lake Desmet (South Dam) built?
Lake Desmet (South Dam) was completed in 1975, making it 51 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 Lake Desmet (South Dam)?
Lake Desmet (South Dam) serves the following purposes: Water Supply. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Lake Desmet (South Dam)?
Lake Desmet (South Dam) has a dam height of 80 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 Lake Desmet (South Dam) last inspected?
Lake Desmet (South Dam) was last inspected on July 19, 2019. Inspection dates indicate when a formal review occurred, not the results of that inspection.