Greenwood Afterbay Dam
Key Takeaway
Greenwood Afterbay Dam is classified as significant hazard in Michigan. It was completed in 1973 and is 53 years old. Its primary use is water supply. Significant hazard means failure could cause economic or environmental damage. Learn more.
Physical Details
| Dam Height | 41 ft (taller than 94.9% in MI) |
| Dam Length | 610 ft |
| Dam Type | Concrete |
| Max Storage | 1.1K acre-ft |
| Normal Storage | 480 acre-ft |
| Surface Area | 50 acres |
| Drainage Area | 71 sq mi |
| Max Discharge | 1,200 cfs |
| Year Completed | 1973 (53 years old) |
| NID ID | MI00114 |
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
Tilden Mining Company LC
Private
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What is the hazard classification of Greenwood Afterbay Dam?
Greenwood Afterbay 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 Greenwood Afterbay Dam?
Greenwood Afterbay Dam is owned by Tilden Mining Company LC (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Greenwood Afterbay Dam built?
Greenwood Afterbay Dam was completed in 1973, making it 53 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 Greenwood Afterbay Dam?
Greenwood Afterbay Dam serves the following purposes: Water Supply. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Greenwood Afterbay Dam?
Greenwood Afterbay Dam has a dam height of 41 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 Greenwood Afterbay Dam last inspected?
Greenwood Afterbay Dam was last inspected on December 1, 2016. Inspection dates indicate when a formal review occurred, not the results of that inspection.