Earl Hanrahan
Key Takeaway
Earl Hanrahan is classified as low hazard in South Dakota. It was completed in 1949 and is 77 years old. Its primary use is fire protection.
Physical Details
| Dam Height | 12 ft (taller than 3% in SD) |
| Dam Length | 200 ft |
| Dam Type | Earth |
| Max Storage | 67 acre-ft |
| Normal Storage | 24 acre-ft |
| Max Discharge | 300 cfs |
| Year Completed | 1949 (77 years old) |
| NID ID | SD01777 |
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
EARL HANRAHAN
Private
Nearby Dams
Sd Noname 201
Haakon, SD
Significant Hazard 20 ftSd Noname 280
Haakon, SD
Low Hazard 16 ftSd Noname 197
Haakon, SD
Low Hazard 15 ftDeuchar Dam
Haakon, SD
Low Hazard 19 ftSd Noname 278
Haakon, SD
Low Hazard 32 ftSd Noname 240
Haakon, SD
Low Hazard 19 ftSd Noname 202
Haakon, SD
Low Hazard 25 ftHanson Dam No. 2
Haakon, SD
Low Hazard 21 ftFrequently Asked Questions
What is the hazard classification of Earl Hanrahan?
Earl Hanrahan 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 Earl Hanrahan?
Earl Hanrahan is owned by EARL HANRAHAN (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Earl Hanrahan built?
Earl Hanrahan was completed in 1949, making it 77 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 Earl Hanrahan?
Earl Hanrahan serves the following purposes: Fire Protection, Stock, Or Small Fish Pond. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Earl Hanrahan?
Earl Hanrahan has a dam height of 12 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.