Button Rock
Key Takeaway
Button Rock is classified as high hazard in Colorado. It was completed in 1969 and is 57 years old. Its primary use is water supply. High hazard means loss of life is likely if the dam fails — it does not indicate the dam's current condition. Learn more.
Physical Details
| Dam Height | 210 ft (taller than 98.8% in CO) |
| Dam Length | 925 ft |
| Dam Type | Earth |
| Max Storage | 20.4K acre-ft |
| Normal Storage | 16.1K acre-ft |
| Surface Area | 222 acres |
| Drainage Area | 99 sq mi |
| Max Discharge | 29,000 cfs |
| Year Completed | 1969 (57 years old) |
| Year Modified | 1990 |
| NID ID | CO00171 |
Safety Information
Loss of human life is likely if the dam fails.
Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?
Ownership
CITY OF LONGMONT (HUSON, KEN)
Local Government
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High Hazard 20 ftFrequently Asked Questions
What is the hazard classification of Button Rock?
Button Rock is classified as High Hazard. Loss of human life is likely if the dam fails. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.
Who owns and operates Button Rock?
Button Rock is owned by CITY OF LONGMONT (HUSON, KEN) (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Button Rock built?
Button Rock was completed in 1969, making it 57 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 Button Rock?
Button Rock 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 Button Rock?
Button Rock has a dam height of 210 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 Button Rock last inspected?
Button Rock was last inspected on August 12, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.