Structure No. 12
Key Takeaway
Structure No. 12 is classified as significant hazard in Illinois. It was completed in 1974 and is 52 years old. Its primary use is recreation. Significant hazard means failure could cause economic or environmental damage. Learn more.
Physical Details
| Dam Height | 54 ft (taller than 93.2% in IL) |
| Dam Length | 1,450 ft |
| Dam Type | Earth |
| Max Storage | 4.4K acre-ft |
| Normal Storage | 1.4K acre-ft |
| Surface Area | 186 acres |
| Drainage Area | 11 sq mi |
| Max Discharge | 13,728 cfs |
| Year Completed | 1974 (52 years old) |
| NID ID | IL00038 |
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
USDA FS
Federal Government
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Low Hazard 28 ftFrequently Asked Questions
What is the hazard classification of Structure No. 12?
Structure No. 12 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 Structure No. 12?
Structure No. 12 is owned by USDA FS (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Structure No. 12 built?
Structure No. 12 was completed in 1974, making it 52 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 Structure No. 12?
Structure No. 12 serves the following purposes: Recreation, Water Supply. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Structure No. 12?
Structure No. 12 has a dam height of 54 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 Structure No. 12 last inspected?
Structure No. 12 was last inspected on September 23, 2016. Inspection dates indicate when a formal review occurred, not the results of that inspection.