Coffeen Lake Dam
Key Takeaway
Coffeen Lake Dam is classified as significant hazard in Illinois. It was completed in 1964 and is 62 years old. Its primary use is other. Significant hazard means failure could cause economic or environmental damage. Learn more.
Physical Details
| Dam Height | 70 ft (taller than 97.3% in IL) |
| Dam Length | 1,300 ft |
| Dam Type | Earth |
| Max Storage | 35.8K acre-ft |
| Normal Storage | 22.0K acre-ft |
| Surface Area | 1,096 acres |
| Drainage Area | 19 sq mi |
| Max Discharge | 8,430 cfs |
| Year Completed | 1964 (62 years old) |
| NID ID | IL00135 |
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
DYNEGY MIDWEST GENERATION, INC.
Public Utility
Nearby Dams
Coffeen East Fork Shoal Creek Gate Dam
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Low Hazard 12 ftCoffeen Station Ash Pond 2 Dam
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Significant HazardCoffeen Station Coal Yard Pond Dam
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Significant Hazard 20 ftCoffeen Power Sta. Supplemental Cooling Lake Dam
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Significant Hazard 21 ftCoffeen Station Ash Pond 1 Dam
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Significant HazardCoffeen Gmf Recycle Pond Dam
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Low Hazard 16 ftBell Pond Dam 1
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Low Hazard 27 ftCoffeen Southwest Detention Pond Dam
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Low Hazard 23 ftFrequently Asked Questions
What is the hazard classification of Coffeen Lake Dam?
Coffeen Lake Dam 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 Coffeen Lake Dam?
Coffeen Lake Dam is owned by DYNEGY MIDWEST GENERATION, INC. (Public Utility). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Coffeen Lake Dam built?
Coffeen Lake Dam was completed in 1964, making it 62 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 Coffeen Lake Dam?
Coffeen Lake Dam serves the following purposes: Other. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Coffeen Lake Dam?
Coffeen Lake Dam has a dam height of 70 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 Coffeen Lake Dam last inspected?
Coffeen Lake Dam was last inspected on November 16, 2020. Inspection dates indicate when a formal review occurred, not the results of that inspection.