Upper Big Nemaha L-4
Key Takeaway
Upper Big Nemaha L-4 is classified as significant hazard in Nebraska. It was completed in 1971 and is 55 years old. Its primary use is flood risk reduction. Significant hazard means failure could cause economic or environmental damage. Learn more.
Physical Details
| Dam Height | 25 ft (taller than 46.7% in NE) |
| Dam Length | 700 ft |
| Dam Type | Earth |
| Max Storage | 371 acre-ft |
| Normal Storage | 64 acre-ft |
| Surface Area | 15 acres |
| Drainage Area | 1 sq mi |
| Max Discharge | 6,384 cfs |
| Year Completed | 1971 (55 years old) |
| NID ID | NE00549 |
Safety Information
No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities.
Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?
Ownership
Nemaha Natural Resources District
Local Government
Nearby Dams
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Significant Hazard 21 ftUpper Big Nemaha 11-A
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Low Hazard 26 ftUpper Big Nemaha L-17
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Low Hazard 19 ftUpper Big Nemaha L-5
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Low Hazard 16 ftVan Pelt Dam
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Low Hazard 24 ftUpper Big Nemaha G-24
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Significant Hazard 29 ftFrequently Asked Questions
What is the hazard classification of Upper Big Nemaha L-4?
Upper Big Nemaha L-4 is classified as Significant Hazard. No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.
Who owns and operates Upper Big Nemaha L-4?
Upper Big Nemaha L-4 is owned by Nemaha Natural Resources District (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Upper Big Nemaha L-4 built?
Upper Big Nemaha L-4 was completed in 1971, making it 55 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 Upper Big Nemaha L-4?
Upper Big Nemaha L-4 serves the following purposes: Flood Risk Reduction. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Upper Big Nemaha L-4?
Upper Big Nemaha L-4 has a dam height of 25 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 Upper Big Nemaha L-4 last inspected?
Upper Big Nemaha L-4 was last inspected on April 19, 2023. Inspection dates indicate when a formal review occurred, not the results of that inspection.