Ralph Hennemann Lake dam
Ralph Hennemann Lake
Ralph Hennemann Lake, located in Scott County, Missouri, was designed by the USDA NRCS and completed in 1992 for the primary purpose of flood risk reduction. This earth dam structure on Ramsey Creek has a height of 25 feet and a hydraulic height of 20 feet, with a storage capacity of 212 acre-feet. The lake covers a surface area of 3 acres and serves multiple purposes including fish and wildlife habitat, flood risk reduction, and recreational activities.
With its uncontrolled spillway and low hazard potential, Ralph Hennemann Lake provides a valuable resource for the local community while also contributing to the overall water management in the area. The dam's structure, made of stone core and soil foundation, has not been rated for its condition assessment, but it stands as a moderate risk (3) according to the risk assessment. Despite not being regulated or inspected by the state, the lake remains a vital part of the watershed, with a drainage area of 128 acres and a maximum discharge capacity of 239 cubic feet per second.
Although Ralph Hennemann Lake does not have outlet gates or associated structures, its presence on Ramsey Creek plays a significant role in managing water flow and mitigating flood risks in the region. As a private-owned reservoir, the lake offers a serene environment for outdoor enthusiasts and serves as a reminder of the importance of sustainable water resource management in the face of changing climate patterns.
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 Ralph Hennemann Lake -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Mississippi River At Thebes | 269,000 cfs | → |
| Little River Ditch No. 1 Near Morehouse | 219 cfs | → |
| Castor River At Zalma | 158 cfs | → |
| Cache River At Forman | 3 cfs | → |
| Bayou Creek Near Grahamville | 5 cfs | → |
| Little Bayou Creek Near Grahamville | 1 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Ralph Hennemann Lake.
Boat launches
- 2nd Street Thebes
- Red Star Access
- State Highway U Cape Girardeau County
- Clear Creek Levee Road Union County
- Front Mound City
- Mill Road Pulaski County
Campgrounds
- General Watkins Conservation Area - Mdc
- Lake Girardeau Conservation Area - Mdc
- Trail Of Tears State Park
- Trail Of Tears State Forest
- Pine Hills Campground
- Pine Hills
Paddle runs
- 1 Mile West Of Alto Pass, Il To 1/2 Mile South Of Confluence With Clear Creek, West Of Trail Of Tears State Forest
- 1/2 Mile Downstream Of Confluence With Kinkaid Creek To Confluence With Mississippi River, Approx 4 Miles South Of Grand Tower, Il
- Forest Boundary At North Section Line Of Sec 4, T33n, R5e To Forest Boundary At South Section Line Of Sec 35, T32n, R5e
Track Ralph Hennemann Lake 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 Ralph Hennemann Lake
Where does the data for Ralph Hennemann Lake 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 Ralph Hennemann Lake.