St Marys River Watershed Site 1
Key Takeaway
St Marys River Watershed Site 1 is classified as high hazard in Maryland. It was completed in 1975 and is 51 years old. Its primary use is flood risk reduction. 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 | 38 ft (taller than 83.7% in MD) |
| Dam Length | 1,670 ft |
| Dam Type | Earth |
| Max Storage | 9.6K acre-ft |
| Normal Storage | 3.2K acre-ft |
| Surface Area | 250 acres |
| Drainage Area | 9 sq mi |
| Max Discharge | 20,576 cfs |
| Year Completed | 1975 (51 years old) |
| Year Modified | 1975 |
| NID ID | MD00028 |
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
MD DNR-Public Lands, Engineering & Constr-Southern
State Government
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Significant Hazard 18 ftHolton Pond Dam
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Significant Hazard 45 ftClair Peake Dam (Md 235)
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Significant Hazard 74 ftFrequently Asked Questions
What is the hazard classification of St Marys River Watershed Site 1?
St Marys River Watershed Site 1 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 St Marys River Watershed Site 1?
St Marys River Watershed Site 1 is owned by MD DNR-Public Lands, Engineering & Constr-Southern (State Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was St Marys River Watershed Site 1 built?
St Marys River Watershed Site 1 was completed in 1975, making it 51 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 St Marys River Watershed Site 1?
St Marys River Watershed Site 1 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 St Marys River Watershed Site 1?
St Marys River Watershed Site 1 has a dam height of 38 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 St Marys River Watershed Site 1 last inspected?
St Marys River Watershed Site 1 was last inspected on December 5, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.