Grady Wilson Jr. dam
Grady Wilson Jr.
Grady Wilson Jr. is a privately owned dam located in Perkins, South Dakota, along the tributary of Moreau River. Built in 1951, this earth dam stands at a height of 20 feet and has a storage capacity of 54 acre-feet. While the dam is primarily used for water resource management, it also serves as a regulatory structure under the supervision of the South Dakota Department of Environment and Natural Resources (DENR).
Despite its low hazard potential and currently unrated condition assessment, Grady Wilson Jr. plays a crucial role in the local water infrastructure, providing flood control and water storage benefits to the surrounding area. With a maximum discharge capacity of 150 cubic feet per second, this dam ensures the safety and stability of the downstream areas during heavy rainfall events. Additionally, its presence is vital for maintaining the ecological balance of the region and supporting the overall water resource management efforts in South Dakota.
As a significant feature in the St. Paul District under the ownership of private entities, Grady Wilson Jr. remains a key structure in the state's water regulatory framework. With state-mandated inspections, permitting, and enforcement in place, this dam exemplifies the commitment to maintaining safe and reliable water resources for both human and environmental needs. As water resource and climate enthusiasts, understanding the critical role of dams like Grady Wilson Jr. is essential in safeguarding our water systems and preparing for the challenges posed by a changing climate.
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 Grady Wilson Jr. -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Moreau R Near Faith Sd | 78 cfs | → |
| South Fork Grand R Near Cash Sd | 25 cfs | → |
| North Fork Grand R Near White Butte Sd | 2 cfs | → |
| Cheyenne R Near Plainview Sd | 1,810 cfs | → |
| Belle Fourche River Near Elm Springs | 277 cfs | → |
| Belle Fourche R Near Sturgis Sd | 272 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Grady Wilson Jr..
Track Grady Wilson Jr. 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 Grady Wilson Jr.
Where does the data for Grady Wilson Jr. 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 Grady Wilson Jr..