Great Western
Key Takeaway
Great Western is classified as high hazard in Colorado. It was completed in 1903 and is 123 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 | 70 ft (taller than 92.6% in CO) |
| Dam Length | 1,885 ft |
| Dam Type | Earth |
| Max Storage | 4.5K acre-ft |
| Normal Storage | 2.2K acre-ft |
| Surface Area | 150 acres |
| Drainage Area | 4 sq mi |
| Max Discharge | 6,600 cfs |
| Year Completed | 1903 (123 years old) |
| Year Modified | 2003 |
| NID ID | CO00091 |
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 BROOMFIELD (MIDDLETON, BRENNAN)
Local Government
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What is the hazard classification of Great Western?
Great Western 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 Great Western?
Great Western is owned by CITY OF BROOMFIELD (MIDDLETON, BRENNAN) (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Great Western built?
Great Western was completed in 1903, making it 123 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 Great Western?
Great Western 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 Great Western?
Great Western has a dam height of 70 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 Great Western last inspected?
Great Western was last inspected on May 3, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.