Johnston Dam
Key Takeaway
Johnston Dam is classified as significant hazard in Iowa. It was completed in 2005 and is 21 years old. Its primary use is fire protection. Significant hazard means failure could cause economic or environmental damage. Learn more.
Physical Details
| Dam Height | 30 ft (taller than 48.2% in IA) |
| Dam Length | 527 ft |
| Dam Type | Earth |
| Max Storage | 193 acre-ft |
| Normal Storage | 81 acre-ft |
| Surface Area | 11 acres |
| Drainage Area | 0 sq mi |
| Max Discharge | 0 cfs |
| Year Completed | 2005 (21 years old) |
| NID ID | IA03692 |
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
James E Johnston
Private
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What is the hazard classification of Johnston Dam?
Johnston 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 Johnston Dam?
Johnston Dam is owned by James E Johnston (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Johnston Dam built?
Johnston Dam was completed in 2005, making it 21 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 Johnston Dam?
Johnston Dam serves the following purposes: Fire Protection, Stock, Or Small Fish Pond. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Johnston Dam?
Johnston Dam has a dam height of 30 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.