Main
Key Takeaway
Main is classified as high hazard in Colorado. It was completed in 1908 and is 118 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 | 45 ft (taller than 85.3% in CO) |
| Dam Length | 1,081 ft |
| Dam Type | Earth |
| Max Storage | 1.3K acre-ft |
| Normal Storage | 583 acre-ft |
| Surface Area | 39 acres |
| Drainage Area | 1 sq mi |
| Max Discharge | 700 cfs |
| Year Completed | 1908 (118 years old) |
| NID ID | CO00301 |
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
AGRICULTURAL DITCH & RESERVOIR COMPANY (ACKER, PET
Private
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Low Hazard 44 ftFrequently Asked Questions
What is the hazard classification of Main?
Main 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 Main?
Main is owned by AGRICULTURAL DITCH & RESERVOIR COMPANY (ACKER, PET (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Main built?
Main was completed in 1908, making it 118 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 Main?
Main 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 Main?
Main has a dam height of 45 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 Main last inspected?
Main was last inspected on March 30, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.