Prairie Lake Dam
Key Takeaway
Prairie Lake Dam is classified as high hazard in Illinois. It was completed in 1999 and is 27 years old. Its primary use is recreation. 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 | 68 ft (taller than 97% in IL) |
| Dam Length | 820 ft |
| Dam Type | Earth |
| Max Storage | 6.1K acre-ft |
| Normal Storage | 3.4K acre-ft |
| Surface Area | 210 acres |
| Drainage Area | 3 sq mi |
| Max Discharge | 9,846 cfs |
| Year Completed | 1999 (27 years old) |
| NID ID | IL50417 |
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
ILLINOIS DEPARTMENT OF NATURAL RESOURCES
State Government
Nearby Dams
Drake Lake Dam
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Low Hazard 51 ftLongs Lake Dam
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Low Hazard 28 ftFinger Lake Dam
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Low Hazard 27 ftJurgens Brothers Lake Dam
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Low Hazard 28 ftVirginia Lake Dam
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Significant Hazard 42 ftBraun Pond Dam
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Significant Hazard 26 ftFrequently Asked Questions
What is the hazard classification of Prairie Lake Dam?
Prairie Lake 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 Prairie Lake Dam?
Prairie Lake Dam is owned by ILLINOIS DEPARTMENT OF NATURAL RESOURCES (State Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Prairie Lake Dam built?
Prairie Lake Dam was completed in 1999, making it 27 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 Prairie Lake Dam?
Prairie Lake Dam serves the following purposes: Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Prairie Lake Dam?
Prairie Lake Dam has a dam height of 68 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 Prairie Lake Dam last inspected?
Prairie Lake Dam was last inspected on October 24, 2019. Inspection dates indicate when a formal review occurred, not the results of that inspection.