Upper Big Nemaha 11-A is a crucial flood risk reduction structure located in Lancaster, Nebraska, designed by the USDA NRCS and regulated by the Nebraska Department of Natural Resources.
Wind
Humidity
Completed in 1971, this earth dam stands at 38 feet high, with a storage capacity of 1148 acre-feet and a drainage area of 2.4 square miles. Despite its age, the dam is in satisfactory condition and has a high hazard potential due to its location along the TR-Mid Br Big Nemaha River.
With a primary purpose of flood risk reduction, Upper Big Nemaha 11-A plays a vital role in protecting the surrounding area from potential inundation. Its satisfactory condition, regular inspections, and enforcement by the Nebraska DNR ensure that the dam remains effective in managing floodwaters and safeguarding the community of Firth. The presence of this structure highlights the collaborative efforts between local government, federal agencies, and regulatory bodies in ensuring the safety and resilience of water resources in Nebraska.
Year Completed |
1971 |
Dam Length |
974 |
Dam Height |
36 |
River Or Stream |
TR-MID BR BIG NEMAHA RIVER |
Primary Dam Type |
Earth |
Surface Area |
25 |
Hydraulic Height |
36 |
Drainage Area |
2.4 |
Nid Storage |
1148 |
Structural Height |
38 |
Hazard Potential |
High |
Foundations |
Soil |
Nid Height |
38 |