Lake Mcmaster Dam
Key Takeaway
Lake Mcmaster Dam is classified as high hazard in Illinois. It was completed in 1981 and is 45 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 | 81 ft (taller than 98.4% in IL) |
| Dam Length | 850 ft |
| Dam Type | Earth |
| Max Storage | 5.4K acre-ft |
| Normal Storage | 4.9K acre-ft |
| Surface Area | 178 acres |
| Drainage Area | 2 sq mi |
| Max Discharge | 4,125 cfs |
| Year Completed | 1981 (45 years old) |
| Year Modified | 2002 |
| NID ID | IL50344 |
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
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Low Hazard 25 ftFrequently Asked Questions
What is the hazard classification of Lake Mcmaster Dam?
Lake Mcmaster 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 Mcmaster Dam?
Lake Mcmaster 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 Lake Mcmaster Dam built?
Lake Mcmaster Dam was completed in 1981, making it 45 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 Mcmaster Dam?
Lake Mcmaster 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 Lake Mcmaster Dam?
Lake Mcmaster Dam has a dam height of 81 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 Mcmaster Dam last inspected?
Lake Mcmaster Dam was last inspected on July 8, 2020. Inspection dates indicate when a formal review occurred, not the results of that inspection.