Lake Ilo Dam
Key Takeaway
Lake Ilo Dam is classified as high hazard in North Dakota. It was completed in 1937 and is 89 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 | 38 ft (taller than 91.2% in ND) |
| Dam Length | 1,715 ft |
| Dam Type | Earth |
| Max Storage | 31.3K acre-ft |
| Normal Storage | 5.1K acre-ft |
| Surface Area | 990 acres |
| Drainage Area | 129 sq mi |
| Max Discharge | 30,716 cfs |
| Year Completed | 1937 (89 years old) |
| NID ID | ND00321 |
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
US FISH AND WILDLIFE SERVICE
Federal Government
Nearby Dams
Frequently Asked Questions
What is the hazard classification of Lake Ilo Dam?
Lake Ilo 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 Ilo Dam?
Lake Ilo Dam is owned by US FISH AND WILDLIFE SERVICE (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Lake Ilo Dam built?
Lake Ilo Dam was completed in 1937, making it 89 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 Ilo Dam?
Lake Ilo 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 Ilo Dam?
Lake Ilo Dam has a dam height of 38 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 Ilo Dam last inspected?
Lake Ilo Dam was last inspected on September 27, 2017. Inspection dates indicate when a formal review occurred, not the results of that inspection.