Nolan Sexton dam
Nolan Sexton
Nolan Sexton, a privately owned earth dam located on the TR MOREAU RIVER in Perkins, South Dakota, was completed in 1949 and stands at a height of 23 feet with a length of 430 feet. The dam has a NID storage capacity of 138 acre-feet, offering crucial water resource management for the surrounding area. Despite its age, the dam is classified as having a low hazard potential and is currently not rated for its condition assessment.
Managed by the South Dakota Department of Environment and Natural Resources (DENR), Nolan Sexton is regulated, permitted, inspected, and enforced by the state, ensuring its compliance with safety and environmental standards. With a normal storage capacity of 97 acre-feet and a max discharge of 150 cubic feet per second, the dam plays a vital role in flood control and water supply management in the region. Its location within the St. Paul District of the US Army Corps of Engineers further underscores its significance in the local water resource infrastructure.
As a key element in the water management system of Perkins, South Dakota, Nolan Sexton serves as a reliable structure for mitigating flood risks and ensuring water availability for the community. With its historical significance dating back to the mid-20th century, the dam continues to provide essential services while meeting state regulatory requirements. The collaboration between private ownership, state agencies, and federal entities underscores the importance of multi-level cooperation in safeguarding water resources and addressing climate challenges 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 Nolan Sexton -- 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 | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Nolan Sexton.
More reservoirs
Track Nolan Sexton 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 Nolan Sexton
Where does the data for Nolan Sexton 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 Nolan Sexton.