Slack Reservoir
Key Takeaway
Slack Reservoir is classified as high hazard in Rhode Island. It was completed in 1885 and is 141 years old. Its primary use is recreation. 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 | 15 ft (taller than 66.7% in RI) |
| Dam Length | 220 ft |
| Dam Type | Masonry |
| Max Storage | 1.8K acre-ft |
| Normal Storage | 1.3K acre-ft |
| Surface Area | 150 acres |
| Drainage Area | 2 sq mi |
| Max Discharge | 100 cfs |
| Year Completed | 1885 (141 years old) |
| NID ID | RI03104 |
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
SLACK'S RESERVOIR ASSOCIATION, INC.
Private
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High Hazard 18 ftFrequently Asked Questions
What is the hazard classification of Slack Reservoir?
Slack 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 Slack Reservoir?
Slack Reservoir is owned by SLACK'S RESERVOIR ASSOCIATION, INC. (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Slack Reservoir built?
Slack Reservoir was completed in 1885, making it 141 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 Slack Reservoir?
Slack Reservoir serves the following purposes: Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Slack Reservoir?
Slack Reservoir has a dam height of 15 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 Slack Reservoir last inspected?
Slack Reservoir was last inspected on October 2, 2013. Inspection dates indicate when a formal review occurred, not the results of that inspection.