Johnston
Key Takeaway
Johnston is classified as significant hazard in Colorado. It was completed in 1974 and is 52 years old. Its primary use is irrigation. Significant hazard means failure could cause economic or environmental damage. Learn more.
Physical Details
| Dam Height | 11 ft (taller than 8.7% in CO) |
| Dam Length | 1,530 ft |
| Dam Type | Earth |
| Max Storage | 1.1K acre-ft |
| Normal Storage | 547 acre-ft |
| Surface Area | 82 acres |
| Drainage Area | 0 sq mi |
| Max Discharge | 3,650 cfs |
| Year Completed | 1974 (52 years old) |
| NID ID | CO01827 |
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
FOOTHILLS PARK & RECREATION DISTRICT (INSLEY, COLI
Private
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Low Hazard 8 ftFrequently Asked Questions
What is the hazard classification of Johnston?
Johnston 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?
Johnston is owned by FOOTHILLS PARK & RECREATION DISTRICT (INSLEY, COLI (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Johnston built?
Johnston was completed in 1974, making it 52 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?
Johnston serves the following purposes: Irrigation, Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Johnston?
Johnston has a dam height of 11 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 last inspected?
Johnston was last inspected on March 23, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.