Black Rock
Key Takeaway
Black Rock is classified as low hazard in Pennsylvania. It was completed in 1900 and is 126 years old. Its primary use is water supply.
Physical Details
| Dam Height | 11 ft (taller than 13.2% in PA) |
| Dam Length | 400 ft |
| Dam Type | Timber Crib |
| Max Storage | 221 acre-ft |
| Normal Storage | 221 acre-ft |
| Surface Area | 184 acres |
| Drainage Area | 1,296 sq mi |
| Year Completed | 1900 (126 years old) |
| NID ID | PA00884 |
Safety Information
No probable loss of human life and low economic/environmental losses expected.
Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?
Ownership
EXELON GENERATION COMPANY
Private
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Significant Hazard 15 ftFrequently Asked Questions
What is the hazard classification of Black Rock?
Black Rock is classified as Low Hazard. No probable loss of human life and low economic/environmental losses expected. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.
Who owns and operates Black Rock?
Black Rock is owned by EXELON GENERATION COMPANY (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Black Rock built?
Black Rock was completed in 1900, making it 126 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 Black Rock?
Black Rock serves the following purposes: Water Supply, Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Black Rock?
Black Rock has a dam height of 11 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 Black Rock last inspected?
Black Rock was last inspected on July 27, 2018. Inspection dates indicate when a formal review occurred, not the results of that inspection.