Williams No.1 dam
Williams No.1
Williams No.1 is a privately owned dam located in Mellette, South Dakota, along the tributary of Little White River. Constructed in 1967, this earth dam stands at 25 feet high and spans 325 feet in length, with a storage capacity of 26 acre-feet. While the primary purpose of Williams No.1 is not specified, it is regulated by the South Dakota Department of Environment and Natural Resources (DENR) and is subject to state permitting, inspection, and enforcement.
With a low hazard potential and a current condition assessment of "Not Rated," Williams No.1 serves as a key infrastructure for water resource management in the region. While specific details on the dam's associated structures, inspection frequency, and emergency action plan are not provided, its location within the St. Paul District of the US Army Corps of Engineers signifies a level of oversight and regulation. The dam's presence contributes to the overall water management efforts in the area, ensuring efficient water storage and discharge capabilities for the surrounding community.
As a significant component of the water infrastructure in South Dakota, Williams No.1 plays a crucial role in mitigating flood risks and providing essential water storage for the region. While further details on its operational aspects and risk management measures are not specified in the data, its existence as a state-regulated dam underscores the importance of proper maintenance and oversight to ensure its continued functionality and safety. For water resource and climate enthusiasts, Williams No.1 represents a piece of the broader puzzle in sustainable water management and climate resilience efforts in the region.
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 Williams No.1 -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| White River Near White River | 17 cfs | → |
| Little White R Below White River Sd | 107 cfs | → |
| Little White R Near Rosebud Sd | 124 cfs | → |
| Black Pipe Creek Nr Belvidere | 10 cfs | → |
| Keya Paha R Near Keyapaha Sd | 23 cfs | → |
| White R Near Kadoka Sd | 42 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Williams No.1.
Track Williams No.1 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 Williams No.1
Where does the data for Williams No.1 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 Williams No.1.