Upper Big Nemaha 12-a
Upper Big Nemaha 12-a is an earth dam located in Lancaster County, Nebraska, built in 1986. It carries a Low hazard potential classification and has a satisfactory condition assessment.
About Upper Big Nemaha 12-a
The primary purpose of Upper Big Nemaha 12-a is flood risk reduction. The dam is designed to control downstream flooding by temporarily storing excess water during storms and releasing it at a controlled rate. The dam is owned by Nemaha Natural Resources District (local government). It impounds the Tr-mid Br Big Nemaha River near Firth.
The dam stands 34 feet tall and stretches 625 feet across, creates a reservoir covering 7 acres, has a maximum storage capacity of 149 acre-feet, and collects water from a drainage area of 0 square miles. Completed in 1986, the structure is 40 years old.
This dam has a low hazard potential classification, meaning that failure would cause minimal damage, limited primarily to the dam owner's property, with no expected loss of life. Its condition is rated satisfactory, indicating no existing or potential dam safety deficiencies are recognized. The most recent inspection on record was 05/31/2022.
At 34 feet, this dam is taller than 80% of dams nationwide.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | Nebraska |
| County | Lancaster |
| Nearest City | Firth |
| River/Stream | Tr-mid Br Big Nemaha River |
| Coordinates | 40.52720, -96.62894 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 34 ft |
| Dam Height | 30 ft |
| Dam Length | 625 ft |
| Year Completed | 1986 (40 years old) |
Storage & Hydraulics
| NID Storage | 149 acre-ft |
| Max Storage | 149 acre-ft |
| Normal Storage | 29 acre-ft |
| Surface Area | 7 acres |
| Drainage Area | 0 sq mi |
| Max Discharge | 156 cfs |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | Nemaha Natural Resources District |
| Owner Type | Local Government |
| Hazard Classification | Low |
| Condition Assessment | Satisfactory |
| Last Inspection | 05/31/2022 |
| Emergency Action Plan | Not Required |
Identifiers
| NID ID | NE02262 |
| Federal ID | NE02262 |
| More Info | State Dam Safety Program |