Thorald Dam
Key Takeaway
Thorald Dam is classified as low hazard in Washington. It was completed in 1988 and is 38 years old. Its primary use is irrigation.
Physical Details
| Dam Length | 400 ft |
| Dam Type | Earth |
| Max Storage | 98 acre-ft |
| Normal Storage | 85 acre-ft |
| Surface Area | 8 acres |
| Drainage Area | 0 sq mi |
| Max Discharge | 15 cfs |
| Year Completed | 1988 (38 years old) |
| NID ID | WA00579 |
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
San Juan Preservation Trust
Private
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Low HazardFrequently Asked Questions
What is the hazard classification of Thorald Dam?
Thorald Dam 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 Thorald Dam?
Thorald Dam is owned by San Juan Preservation Trust (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Thorald Dam built?
Thorald Dam was completed in 1988, making it 38 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 Thorald Dam?
Thorald Dam serves the following purposes: Irrigation, Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.