Croy Subwatershed Site A4-4572 Reservoir Report
Last Updated: December 14, 2025
Located in Monona, Iowa, the Croy Subwatershed Site A4-4572 is a small earth dam completed in 1951 for fire protection, stock, or small fish pond purposes.
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Summary
Managed by the local government, this site is regulated by the Iowa Department of Natural Resources and is designed by the USDA NRCS. With a low hazard potential and a moderate risk assessment rating, this dam has a storage capacity of 62 acre-feet and serves a drainage area of 0.52 square miles in the Maple River watershed.
The Croy Subwatershed Site A4-4572 plays a crucial role in flood risk reduction and water resource management in the region. Although the dam's condition is currently not rated, it is regularly inspected and maintained by state regulatory agencies to ensure its structural integrity and safety. With a spillway type of uncontrolled and a structural height of 20 feet, this dam serves as a vital infrastructure for the community of Little Sioux and surrounding areas.
Enthusiasts of water resources and climate will find the Croy Subwatershed Site A4-4572 a fascinating example of local government-led water management efforts. With its historic significance as a fire protection and stock pond structure, as well as its contribution to flood risk reduction in the Maple River watershed, this site showcases the importance of sustainable water infrastructure in rural Iowa. As the site continues to be monitored and managed by state agencies, it stands as a testament to the collaborative efforts towards resilient water resource management in the region.
Year Completed |
1951 |
Dam Height |
20 |
River Or Stream |
TR- MAPLE RIVER |
Primary Dam Type |
Earth |
Surface Area |
3 |
Drainage Area |
0.52 |
Nid Storage |
62 |
Hazard Potential |
Low |
Foundations |
Soil |
Nid Height |
20 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
Little Sioux River Near Turin
|
1040cfs |
Monona-Harrison Ditch Near Turin
|
158cfs |
Maple River At Mapleton
|
323cfs |
Soldier River At Pisgah
|
112cfs |
Missouri River At Decatur
|
14900cfs |
West Fork Ditch At Hornick
|
80cfs |
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.
Croy Subwatershed Site A4-4572