Left Hand Valley
Key Takeaway
Left Hand Valley is classified as high hazard in Colorado. It was completed in 1952 and is 74 years old. Its primary use is irrigation. 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 | 54 ft (taller than 89.9% in CO) |
| Dam Length | 1,035 ft |
| Dam Type | Earth |
| Max Storage | 2.8K acre-ft |
| Normal Storage | 1.6K acre-ft |
| Surface Area | 113 acres |
| Drainage Area | 3 sq mi |
| Max Discharge | 12,367 cfs |
| Year Completed | 1952 (74 years old) |
| Year Modified | 2002 |
| NID ID | CO00177 |
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
LEFT HAND DITCH COMPANY (TERRY PLUMMER)
Private
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High Hazard 45 ftFrequently Asked Questions
What is the hazard classification of Left Hand Valley?
Left Hand Valley 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 Left Hand Valley?
Left Hand Valley is owned by LEFT HAND DITCH COMPANY (TERRY PLUMMER) (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Left Hand Valley built?
Left Hand Valley was completed in 1952, making it 74 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 Left Hand Valley?
Left Hand Valley serves the following purposes: Irrigation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Left Hand Valley?
Left Hand Valley has a dam height of 54 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 Left Hand Valley last inspected?
Left Hand Valley was last inspected on June 23, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.