Middle Big Nemaha 18 dam
Middle Big Nemaha 18
Middle Big Nemaha 18 is a locally owned earth dam located in Tecumseh, Nebraska, along Brewers Branch. Designed by USDA NRCS and completed in 2003, this dam serves primarily for flood risk reduction, with a height of 50 feet and a storage capacity of 1114 acre-feet. The dam stands at a structural height of 56 feet and spans 844 feet in length, encompassing a surface area of 18 acres and draining a watershed area of 3.3 square miles.
Managed by the Nebraska Department of Natural Resources, Middle Big Nemaha 18 is regulated, inspected, and enforced by state agencies to ensure its safety and functionality. The dam's hazard potential is considered significant, although its condition was assessed as satisfactory as of April 2019. With a maximum discharge capacity of 4334 cubic feet per second, this dam plays a critical role in mitigating flood risks in the region, safeguarding nearby communities and infrastructure from potential water-related disasters.
Enthusiasts of water resources and climate will appreciate the strategic importance of Middle Big Nemaha 18 in protecting the Johnson County area from flooding events. As a key infrastructure for flood risk reduction, this earth dam showcases the collaborative efforts between local government authorities, USDA NRCS, and state regulatory agencies to safeguard the community's well-being and resilience against natural disasters. The dam's satisfactory condition assessment and regular inspections underscore its vital role in water resource management and climate adaptation efforts in Nebraska.
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 Middle Big Nemaha 18 -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| North Fork Big Nemaha River At Humboldt | 850 cfs | → |
| Little Nemaha River At Auburn | 743 cfs | → |
| Big Blue R At Barneston Nebr | 2,280 cfs | → |
| Salt Creek At Roca | 6 cfs | → |
| Turkey C Nr Seneca | 147 cfs | → |
| Turkey Creek Near De Witt | 195 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Middle Big Nemaha 18.
Boat launches
- Wirth Brothers
- Burchard Lake Wma
- Wolf - Wildcat
- Rockford Lake Sra
- Kirkmans Cove Lake
- Bear Pierce Lake 2a
Track Middle Big Nemaha 18 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 Middle Big Nemaha 18
Where does the data for Middle Big Nemaha 18 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 Significant 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 Middle Big Nemaha 18.