Johnston Dam
Key Takeaway
Johnston Dam is classified as low hazard in Iowa. It was completed in 1973 and is 53 years old. Its primary use is fire protection.
Physical Details
| Dam Height | 36 ft (taller than 74.2% in IA) |
| Dam Length | 320 ft |
| Dam Type | Earth |
| Max Storage | 75 acre-ft |
| Normal Storage | 47 acre-ft |
| Surface Area | 5 acres |
| Drainage Area | 0 sq mi |
| Max Discharge | 0 cfs |
| Year Completed | 1973 (53 years old) |
| NID ID | IA01642 |
Safety Information
No probable loss of human life and low economic/environmental losses expected.
Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?
Ownership
Joseph M Johnston
Private
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Low Hazard 27 ftFrequently Asked Questions
What is the hazard classification of Johnston Dam?
Johnston Dam is classified as Low Hazard. No probable loss of human life and low economic/environmental losses expected. 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 Joseph M 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 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 Johnston Dam?
Johnston Dam serves the following purposes: Fire Protection, Stock, Or Small Fish Pond, Recreation. 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 36 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 Johnston Dam last inspected?
Johnston Dam was last inspected on March 5, 1992. Inspection dates indicate when a formal review occurred, not the results of that inspection.