Sumo dam
Sumo
Sumo is a state-regulated water resource located in Chouteau, Montana, specifically in Box Elder. Built in 1934, this earth dam stands at 20 feet in height and spans 350 feet in length, providing vital fire protection, stock, and small fish pond purposes. It is under the jurisdiction of the Montana Department of Natural Resources and Conservation (DNRC) and is regularly inspected, permitted, and enforced by the state agency.
With a low hazard potential and a condition assessment of "Not Rated," Sumo serves as a reliable resource for the local community. The dam has a storage capacity of 92 acre-feet and a maximum storage of 92 acre-feet, with a normal storage level of 20 acre-feet. Despite its age, Sumo remains a functional and essential structure for managing water resources in the area. While it has not been modified in recent years, the dam continues to meet the necessary guidelines and regulations for efficient operation.
In the event of emergencies, the dam's Emergency Action Plan (EAP) status and preparedness are not currently rated or updated, but the risk management measures and potential risks associated with the structure are under constant evaluation. As a key component of water management in the region, Sumo plays a crucial role in ensuring water safety and resource availability for the surrounding community, making it a significant asset for water resource and climate enthusiasts to monitor and appreciate.
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 Sumo -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Missouri River At Virgelle Mt | 7,010 cfs | → |
| Teton River At Loma Mt | 26 cfs | → |
| Marias River Near Loma Mt | 504 cfs | → |
| Missouri River At Fort Benton Mt | 6,420 cfs | → |
| Marias River Near Chester Mt | 604 cfs | → |
| Big Sandy Creek Near Havre Mt | 4 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Sumo.
Boat launches
- Coal Banks Landing
- Wood Bottom Recreation Area
- Seineurs Reach
- Little Sandy Coulee Rec Site
- Lone Tree Coulee
- Monroe Island
Campgrounds
- Coal Banks Landing
- Black Bluff Rapids
- Wood Bottom Recreation Area
- Wood Bottom Recreation Area - Umrbnm
- Wood Bottom
- Seineurs Reach
Fishing spots
More reservoirs
Track Sumo 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 Sumo
Where does the data for Sumo 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 Sumo.