Blair Gap
Key Takeaway
Blair Gap is classified as high hazard in Pennsylvania. It was completed in 1907 and is 119 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 | 47 ft (taller than 82.9% in PA) |
| Dam Length | 316 ft |
| Dam Type | Gravity |
| Max Storage | 100 acre-ft |
| Normal Storage | 92 acre-ft |
| Surface Area | 4 acres |
| Drainage Area | 3 sq mi |
| Year Completed | 1907 (119 years old) |
| NID ID | PA00521 |
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
ALTOONA WATER AUTHORITY
Local Government
Nearby Dams
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High Hazard 51 ftReservoir No 4
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Significant Hazard 20 ftUpper Kittanning
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High Hazard 45 ftWilliam L. Cochran Impounding
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Low Hazard 40 ftLake Altoona
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High Hazard 65 ftFrequently Asked Questions
What is the hazard classification of Blair Gap?
Blair Gap 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 Blair Gap?
Blair Gap is owned by ALTOONA WATER AUTHORITY (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Blair Gap built?
Blair Gap was completed in 1907, making it 119 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 Blair Gap?
Blair Gap 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 Blair Gap?
Blair Gap has a dam height of 47 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 Blair Gap last inspected?
Blair Gap was last inspected on May 13, 2020. Inspection dates indicate when a formal review occurred, not the results of that inspection.