Marys Lake Dike No. 1
Key Takeaway
Marys Lake Dike No. 1 is classified as high hazard in Colorado. It was completed in 1948 and is 78 years old. Its primary use is hydroelectric. 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 | 29 ft (taller than 64% in CO) |
| Dam Length | 820 ft |
| Dam Type | Earth |
| Max Storage | 1.1K acre-ft |
| Normal Storage | 927 acre-ft |
| Surface Area | 47 acres |
| Drainage Area | 1 sq mi |
| Year Completed | 1948 (78 years old) |
| NID ID | CO01660 |
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
RECLAMATION
Federal Government
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Low Hazard 9 ftFrequently Asked Questions
What is the hazard classification of Marys Lake Dike No. 1?
Marys Lake Dike No. 1 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 Marys Lake Dike No. 1?
Marys Lake Dike No. 1 is owned by RECLAMATION (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Marys Lake Dike No. 1 built?
Marys Lake Dike No. 1 was completed in 1948, making it 78 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 Marys Lake Dike No. 1?
Marys Lake Dike No. 1 serves the following purposes: Hydroelectric. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Marys Lake Dike No. 1?
Marys Lake Dike No. 1 has a dam height of 29 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 Marys Lake Dike No. 1 last inspected?
Marys Lake Dike No. 1 was last inspected on August 5, 2020. Inspection dates indicate when a formal review occurred, not the results of that inspection.