Riley Dam
Key Takeaway
Riley Dam is classified as significant hazard in Michigan. It was completed in 1923 and is 103 years old. Its primary use is hydroelectric. Significant hazard means failure could cause economic or environmental damage. Learn more.
Physical Details
| Dam Height | 20 ft (taller than 70.3% in MI) |
| Dam Length | 824 ft |
| Dam Type | Gravity |
| Max Storage | 5.0K acre-ft |
| Normal Storage | 3.2K acre-ft |
| Surface Area | 518 acres |
| Drainage Area | 523 sq mi |
| Max Discharge | 10,000 cfs |
| Year Completed | 1923 (103 years old) |
| NID ID | MI00533 |
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
Village of Union City
Local Government
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What is the hazard classification of Riley Dam?
Riley 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 Riley Dam?
Riley Dam is owned by Village of Union City (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Riley Dam built?
Riley Dam was completed in 1923, making it 103 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 Riley Dam?
Riley Dam serves the following purposes: Hydroelectric. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Riley Dam?
Riley Dam has a dam height of 20 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 Riley Dam last inspected?
Riley Dam was last inspected on July 28, 2020. Inspection dates indicate when a formal review occurred, not the results of that inspection.