Upper Big Nemaha 20-C is a vital local government-owned earth dam located in Johnson, Nebraska, serving multiple purposes including flood risk reduction.
Wind
Humidity
Built in 1980 by the USDA NRCS, this dam stands at a height of 35 feet and has a storage capacity of 542 acre-feet. With a satisfactory condition assessment and low hazard potential, Upper Big Nemaha 20-C plays a crucial role in protecting the surrounding area from potential flooding events.
Managed by the Nebraska Department of Natural Resources, this dam is subject to state regulation, inspection, and enforcement to ensure its continued safety and effectiveness. The dam's structure consists of stone core and soil foundation, with a length of 828 feet and a maximum discharge capacity of 1893 cubic feet per second. Despite its low hazard potential, regular inspections every 5 years are conducted to maintain its satisfactory condition and readiness for emergencies.
Located on the TR-Big Nemaha River, Upper Big Nemaha 20-C is an essential part of the local water resource infrastructure in Nebraska. With its strategic design and purposeful construction, this earth dam serves as a reliable barrier against flooding and contributes to the overall water management efforts in the region. Its presence underscores the importance of sustainable water resource management and climate resilience in the face of changing environmental conditions.
Year Completed |
1980 |
Dam Length |
828 |
Dam Height |
35 |
River Or Stream |
TR-BIG NEMAHA RIVER |
Primary Dam Type |
Earth |
Surface Area |
14 |
Hydraulic Height |
34 |
Drainage Area |
1.5 |
Nid Storage |
542 |
Structural Height |
40 |
Hazard Potential |
Low |
Foundations |
Soil |
Nid Height |
40 |