Upper Big Nemaha 15-D dam
Upper Big Nemaha 15-D
Upper Big Nemaha 15-D is a local government-owned dam in Lancaster, Nebraska, designed by USDA NRCS and regulated by the Nebraska Department of Natural Resources. Completed in 1974, this Earth-type dam stands at a height of 26 feet and spans 950 feet, serving primarily for flood risk reduction along the TR-MID BR Big Nemaha River. With a normal storage capacity of 155 acre-feet and a maximum discharge of 875 cubic feet per second, this structure plays a crucial role in managing water flow and protecting the surrounding area from potential flood hazards.
The dam's low hazard potential and satisfactory condition assessment indicate its reliability in mitigating flood risks and ensuring community safety. Its last inspection in September 2016 found the structure to be in good working order, with an inspection frequency of every 5 years. The dam's location in Firth, Nebraska, highlights its strategic placement within the watershed, contributing to the overall water resource management efforts in the region. As a key component of the local flood control infrastructure, Upper Big Nemaha 15-D plays a vital role in safeguarding the community against potential water-related challenges.
Overall, Upper Big Nemaha 15-D stands as a testament to effective collaboration between local government agencies, regulatory bodies, and design professionals in ensuring the resilience of water resource infrastructure in Nebraska. Through its design and operation, this dam exemplifies the importance of proactive flood risk reduction measures in the face of changing climate patterns and increasing water-related challenges. Its continued maintenance and adherence to regulatory standards underscore the commitment to safeguarding both the environment and local communities from potential water-related risks in the years to come.
Dam data reference
Condition Assessment
- Satisfactory
- No existing or potential dam safety deficiencies are recognized. Acceptable performance is expected under all loading conditions (static, hydrologic, seismic) in accordance with the minimum applicable state or federal regulatory criteria or tolerable risk guidelines.
- Fair
- No existing dam safety deficiencies are recognized for normal operating conditions. Rare or extreme hydrologic and/or seismic events may result in a dam safety deficiency. Risk may be in the range to take further action.
- Poor
- A dam safety deficiency is recognized for normal operating conditions which may realistically occur. Remedial action is necessary. POOR may also be used when uncertainties exist as to critical analysis parameters which identify a potential dam safety deficiency.
- Unsatisfactory
- A dam safety deficiency is recognized that requires immediate or emergency remedial action for problem resolution.
- Not Rated
- The dam has not been inspected, is not under state or federal jurisdiction, or has been inspected but, for whatever reason, has not been rated.
Hazard Potential Classification
- High
- Dams assigned the high hazard potential classification are those where failure or mis-operation will probably cause loss of human life.
- Significant
- Dams assigned the significant hazard potential classification are those dams where failure or mis-operation results in no probable loss of human life but can cause economic loss, environmental damage, disruption of lifeline facilities, or impact other concerns. Significant hazard potential classification dams are often located in predominantly rural or agricultural areas but could be in areas with population and significant infrastructure.
- Low
- Dams assigned the low hazard potential classification are those where failure or mis-operation results in no probable loss of human life and low economic and/or environmental losses. Losses are principally limited to the owner's property.
- Undetermined
- Dams for which a downstream hazard potential has not been designated or is not provided.
Plan around the weather
Same NOAA / yr.no feed Snoflo's iOS app uses. Watch the precipitation column on the meteogram -- rain on the basin upstream typically lifts inflow 24-72 hours later.
Next 5 days, hour by hour
Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.
5-day forecast table
Every 3 hours, broken out across temperature, snow, rain, humidity, and wind. Each cell is colour-coded relative to the column min/max.
| Time | Condition | Temp (°F) | Snow (in) | Rain (in) | Humidity (%) | Wind (mps) | Wind dir |
|---|---|---|---|---|---|---|---|
| Loading detailed forecast… | |||||||
15-day temperature & precipitation
Daily temperatures, snow, and rain projected over the next two weeks.
Nearby streamflow gauges
USGS streamgauges around Upper Big Nemaha 15-D -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Salt Creek At Roca | 6 cfs | → |
| Big Blue River Near Crete | 184 cfs | → |
| Salt Creek At Pioneers Blvd At Lincoln | 11 cfs | → |
| Haines Branch At Sw 56th St. At Lincoln | 13 cfs | → |
| Turkey Creek Near De Witt | 127 cfs | → |
| Middle Creek At Sw 40th St. At Lincoln | 1 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Upper Big Nemaha 15-D.
Track Upper Big Nemaha 15-D in the Snoflo app
Save this dam as a favorite and get the local NOAA / yr.no forecast plus regional flow context wherever you are.
About Upper Big Nemaha 15-D
Where does the data for Upper Big Nemaha 15-D come from?
Structural and regulatory data come from the U.S. Army Corps of Engineers' National Inventory of Dams (NID). Weather forecast comes from NOAA / yr.no -- the same feed Snoflo's iOS app uses.
How often is the report updated?
NID structural data refreshes annually as the Corps publishes updated assessments. The weather forecast refreshes throughout the day.
What does the Low hazard rating mean?
The Corps of Engineers' hazard potential classification grades probable consequences if the dam fails: High = probable loss of human life; Significant = no probable loss of human life but possible economic loss / environmental damage; Low = no probable loss of human life, only minor economic / environmental losses. See the Dam Data Reference card above for the full definitions.
What's "% of normal"?
The current storage value compared to the historical average storage on this calendar day. 100% = right on average; values above 100% mean above-normal storage (wet year); values below mean below-normal (dry year or drought).
Can I get alerts when storage crosses a threshold?
Yes -- alerts are managed in the Snoflo iOS app. Favorite this dam, set a threshold, and you'll get a push the moment conditions cross.
Other water bodies near here
Snoflo-tracked reservoirs and dams within driving distance of Upper Big Nemaha 15-D.