Mill Creek Ws Str 4 Reservoir Report
Last Updated: December 19, 2025
Mill Creek WS Str 4, located in Walnut Prairie, Illinois, is a privately owned earth dam constructed in 1976 by the USDA NRCS for flood risk reduction on the TR-Mill Creek E river.
°F
°F
mph
Wind
%
Humidity
Summary
This dam stands at a height of 35 feet and spans 460 feet in length, with a storage capacity of 707 acre-feet and a drainage area of 2.36 square miles. Despite being categorized as having a low hazard potential, it is regulated by the Illinois Department of Natural Resources and undergoes regular inspections by the Natural Resources Conservation Service.
The dam features an uncontrolled spillway with a width of 100 feet and outlet gates that are also uncontrolled. With a moderate risk assessment rating of 3, there are no specific risk management measures or emergency action plans currently in place for the dam. Although the condition assessment is not available, the last inspection in August 2019 deemed it to be in satisfactory condition. With its primary purpose of flood risk reduction, Mill Creek WS Str 4 serves as a crucial infrastructure for managing water resources in the region.
Enthusiasts of water resource management and climate resilience will find Mill Creek WS Str 4 to be an intriguing case study of a privately owned dam playing a significant role in flood risk reduction in Clark County, Illinois. With its historical significance dating back to 1976 and ongoing regulatory oversight by the IDNR and inspections by the NRCS, this earth dam showcases the collaborative efforts between private owners and government agencies to safeguard communities from potential flooding events. As discussions on climate change and extreme weather patterns continue to evolve, the importance of maintaining and enhancing infrastructure like Mill Creek WS Str 4 becomes increasingly vital in ensuring the resilience of water resources in the face of future challenges.
Year Completed |
1976 |
Dam Length |
460 |
Dam Height |
35 |
River Or Stream |
TR- MILL CREEK E |
Primary Dam Type |
Earth |
Surface Area |
18 |
Drainage Area |
2.36 |
Nid Storage |
707 |
Outlet Gates |
Uncontrolled |
Hazard Potential |
Low |
Foundations |
Soil |
Nid Height |
35 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
Wabash River At Terre Haute
|
1770cfs |
Wabash River At Riverton Ind
|
1870cfs |
North Fork Embarras River Near Oblong
|
5cfs |
Big Raccoon Creek At Coxville
|
138cfs |
Busseron Creek Near Carlisle
|
452cfs |
Wabash River At Montezuma
|
2010cfs |
Dam Data Reference
Condition Assessment
SatisfactoryNo 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. Note: Rare or extreme event is defined by the regulatory agency based on their minimum
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. Investigations and studies are necessary.
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.
Not Available
Dams for which the condition assessment is restricted to approved government users.
Hazard Potential Classification
HighDams 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, environment 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.
Not Available
Dams for which the downstream hazard potential is restricted to approved government users.
Mill Creek Ws Str 4