Upper Blackwelder Dam
Key Takeaway
Upper Blackwelder Dam is classified as significant hazard in California. It was completed in 1955 and is 71 years old. Its primary use is flood risk reduction. Significant hazard means failure could cause economic or environmental damage. Learn more.
Physical Details
| Dam Height | 14 ft (taller than 6.7% in CA) |
| Dam Length | 1,000 ft |
| Dam Type | Rockfill |
| Max Storage | 330 acre-ft |
| Normal Storage | 80 acre-ft |
| Surface Area | 35 acres |
| Drainage Area | 6 sq mi |
| Max Discharge | 482 cfs |
| Year Completed | 1955 (71 years old) |
| NID ID | CA10116 |
Safety Information
No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities.
Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?
Ownership
USAF ACC
Federal Government
Nearby Dams
Miller Lake Dam
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Low Hazard 25 ftLower Blackwelder Dam
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Low Hazard 32 ftCamp Far West
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High Hazard 185 ftFrequently Asked Questions
What is the hazard classification of Upper Blackwelder Dam?
Upper Blackwelder Dam is classified as Significant Hazard. No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.
Who owns and operates Upper Blackwelder Dam?
Upper Blackwelder Dam is owned by USAF ACC (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Upper Blackwelder Dam built?
Upper Blackwelder Dam was completed in 1955, making it 71 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 Upper Blackwelder Dam?
Upper Blackwelder Dam serves the following purposes: Flood Risk Reduction, Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Upper Blackwelder Dam?
Upper Blackwelder Dam has a dam height of 14 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 Upper Blackwelder Dam last inspected?
Upper Blackwelder Dam was last inspected on September 15, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.