Sloppy Dam Reservoir Report
Last Updated: December 15, 2025
Sloppy Dam, located in Marshall County, Iowa, is a privately owned earth dam completed in 1999 for fire protection, stock, and small fish pond purposes.
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Summary
The dam stands at a height of 28 feet and spans 404 feet in length, with a storage capacity of 64 acre-feet. The dam is regulated by the Iowa Department of Natural Resources and undergoes regular inspection, enforcement, and permitting to ensure its safe operation.
Despite its low hazard potential, Sloppy Dam is considered to have a moderate risk level and is not currently rated for its condition. The dam features an uncontrolled spillway type and has a surface area of 4.8 acres, serving the Timber Creek tributary. The dam is situated within a drainage area of 0.17 square miles and is designed with soil foundations. While there are no associated locks or outlet gates, the dam remains an essential resource for water conservation and management in the region.
As water resource and climate enthusiasts, monitoring the condition and maintenance of Sloppy Dam is crucial for ensuring its continued effectiveness in providing fire protection and supporting local wildlife. With its moderate risk level and regulatory oversight by the Iowa DNR, efforts to assess and address any potential hazards or concerns surrounding the dam are essential to safeguarding the surrounding community and ecosystem.
Year Completed |
1999 |
Dam Length |
404 |
Dam Height |
28 |
River Or Stream |
TR- TIMBER CREEK |
Primary Dam Type |
Earth |
Surface Area |
4.8 |
Drainage Area |
0.17 |
Nid Storage |
64 |
Hazard Potential |
Low |
Foundations |
Soil |
Nid Height |
28 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
Timber Creek Near Marshalltown
|
37cfs |
Iowa River At Marshalltown
|
1040cfs |
Richland Creek Near Haven
|
12cfs |
Indian Creek Near Mingo
|
79cfs |
South Skunk River At Colfax
|
211cfs |
Walnut Creek Near Hartwick
|
13cfs |
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.
Sloppy Dam