Upper Big Nemaha 12-A is a flood risk reduction dam located in Lancaster, Nebraska, designed by USDA NRCS and completed in 1986.
Wind
Humidity
The dam, with a structural height of 34 feet and a length of 625 feet, serves the primary purpose of mitigating flood risks in the area. It has a low hazard potential and is in satisfactory condition as of the last assessment in June 2017.
Situated on the TR-MID BR Big Nemaha River, Upper Big Nemaha 12-A has a storage capacity of 78 acre-feet and a drainage area of 0.4 square miles. The dam has a normal storage capacity of 29 acre-feet and a maximum discharge of 156 cubic feet per second. With state regulation, inspection, and enforcement in place, the dam is well-maintained and meets guidelines for emergency action preparedness.
Owned by the local government and regulated by the Nebraska Department of Natural Resources, Upper Big Nemaha 12-A plays a crucial role in protecting the surrounding community from potential flood events. Its strategic location and design by the Natural Resources Conservation Service reflect a commitment to water resource management and climate resilience in the region.
Year Completed |
1986 |
Dam Length |
625 |
Dam Height |
30 |
River Or Stream |
TR-MID BR BIG NEMAHA RIVER |
Primary Dam Type |
Earth |
Surface Area |
7 |
Hydraulic Height |
29 |
Drainage Area |
0.4 |
Nid Storage |
78 |
Structural Height |
34 |
Hazard Potential |
Low |
Foundations |
Soil |
Nid Height |
34 |