Ponaganset Reservoir
Key Takeaway
Ponaganset Reservoir is classified as high hazard in Rhode Island. It was completed in 1865 and is 161 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 | 25 ft (taller than 90.1% in RI) |
| Dam Length | 635 ft |
| Dam Type | Earth |
| Max Storage | 3.7K acre-ft |
| Normal Storage | 2.3K acre-ft |
| Surface Area | 230 acres |
| Drainage Area | 2 sq mi |
| Max Discharge | 130 cfs |
| Year Completed | 1865 (161 years old) |
| NID ID | RI01304 |
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
PROVIDENCE WATER SUPPLY BOARD/CITY OF PROVIDENCE
Local Government
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Significant Hazard 6 ftFrequently Asked Questions
What is the hazard classification of Ponaganset Reservoir?
Ponaganset Reservoir 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 Ponaganset Reservoir?
Ponaganset Reservoir is owned by PROVIDENCE WATER SUPPLY BOARD/CITY OF PROVIDENCE (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Ponaganset Reservoir built?
Ponaganset Reservoir was completed in 1865, making it 161 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 Ponaganset Reservoir?
Ponaganset Reservoir 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 Ponaganset Reservoir?
Ponaganset Reservoir has a dam height of 25 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 Ponaganset Reservoir last inspected?
Ponaganset Reservoir was last inspected on April 11, 2014. Inspection dates indicate when a formal review occurred, not the results of that inspection.