Ethan
Key Takeaway
Ethan is classified as low hazard in South Dakota. It was completed in 1936 and is 90 years old. Its primary use is flood risk reduction.
Physical Details
| Dam Height | 15 ft (taller than 11.1% in SD) |
| Dam Length | 750 ft |
| Dam Type | Earth |
| Max Storage | 402 acre-ft |
| Normal Storage | 210 acre-ft |
| Max Discharge | 1,370 cfs |
| Year Completed | 1936 (90 years old) |
| NID ID | SD00022 |
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
GF&P
State Government
Nearby Dams
Frequently Asked Questions
What is the hazard classification of Ethan?
Ethan 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 Ethan?
Ethan is owned by GF&P (State Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Ethan built?
Ethan was completed in 1936, making it 90 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 Ethan?
Ethan serves the following purposes: Flood Risk Reduction, Recreation, Water Supply. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Ethan?
Ethan 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 Ethan last inspected?
Ethan was last inspected on October 4, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.