May Dam dam
May Dam
May Dam, located in Jackson, South Dakota, is a privately owned earth dam that spans 400 feet in length and stands at a height of 24 feet. Completed in 1947, this dam on Potato Creek has a storage capacity of 125 acre-feet, with a maximum discharge of 1,500 cubic feet per second. Despite its low hazard potential and a current condition assessment of "Not Rated," the dam is regulated by the South Dakota Department of Environment and Natural Resources, with state permitting, inspection, and enforcement in place.
Operated by the Natural Resources Conservation Service, May Dam plays a crucial role in water resource management in the region. While specific purposes for the dam are not listed, its primary function as an earth structure demonstrates its importance in flood control, water supply, and environmental conservation. The dam's presence also contributes to the overall ecosystem health of the area, providing benefits beyond its immediate water storage capacity.
As a point of interest for water resource and climate enthusiasts, May Dam serves as a testament to the intersection of human infrastructure and natural ecosystems. With its historical significance and ongoing regulatory oversight, the dam represents a balance between harnessing water resources for societal needs and maintaining the integrity of the surrounding environment. Its location in the St. Paul District, with Congressman Dusty Johnson representing the area, highlights the interconnectedness of water management, government oversight, and community engagement in sustaining critical infrastructure for the benefit of all stakeholders.
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 May Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Bear In The Lodge Cr Near Wanblee Sd | 10 cfs | → |
| White R Near Interior Sd | 19 cfs | → |
| Little White R Near Martin Sd | 12 cfs | → |
| Lake Cr Above Refuge Near Tuthill Sd | 26 cfs | → |
| Lake Cr Below Refuge Near Tuthill Sd | 0 cfs | → |
| White R Near Kadoka Sd | 42 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near May Dam.
Track May Dam 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 May Dam
Where does the data for May Dam 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 May Dam.