Simpson Legion Lake Dam dam
Simpson Legion Lake Dam
Simpson Legion Lake Dam, located in Mendenhall, Mississippi, stands as a vital water resource for the region, serving primarily for recreational purposes since its completion in 1950. The dam, classified as an Earth type with a height of 30 feet and a hydraulic height of 22 feet, holds a storage capacity of 1672 acre-feet and covers a surface area of 77 acres. Despite its relatively small drainage area of 4.18 square miles, the dam plays a critical role in managing water flow along Sellers Creek.
Managed by the Mississippi Department of Environmental Quality, Simpson Legion Lake Dam is subject to regular state inspections, ensuring its structural integrity and compliance with safety regulations. The dam's high hazard potential highlights the importance of effective risk management measures and emergency preparedness. The latest inspection in March 2021 reported the dam's condition as satisfactory, but ongoing monitoring and maintenance are crucial to mitigate any potential risks associated with its operation.
With its scenic surroundings and significant impact on the local water resources, Simpson Legion Lake Dam stands as a testament to responsible water management in the face of changing climate conditions. Enthusiasts and stakeholders alike can appreciate the dam's role in providing not only recreational opportunities but also essential water storage and flow regulation for the community.
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 Simpson Legion Lake Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Strong River At D`Lo | 237 cfs | → |
| Pearl River Nr Rockport | 2,500 cfs | → |
| Leaf River Nr Collins | 470 cfs | → |
| Pearl River Nr Monticello | 2,830 cfs | → |
| Pearl River At Jackson | 1,260 cfs | → |
| Lynch Creek At Jackson | 232 cfs | → |
About Simpson Legion Lake Dam
Where does the data for Simpson Legion Lake 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 High 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 below 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.
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.