Ralston Subwatershed Site 1-2 Reservoir Report
Last Updated: December 14, 2025
Ralston Subwatershed Site 1-2, located in correctionville, Iowa, is a dam constructed in 1969 by the USDA NRCS for fire protection, stock, or small fish pond purposes.
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Summary
This earth dam has a height of 36 feet and a length of 429 feet, providing a storage capacity of 71 acre-feet. The dam is regulated by the Iowa DNR and is designed to reduce flood risks along the TR-Little Sioux River.
With a low hazard potential and a moderate risk assessment score of 3, Ralston Subwatershed Site 1-2 serves as an essential infrastructure for water resource management in Woodbury County, Iowa. The dam's primary purpose, along with its flood risk reduction capabilities, highlights its importance in protecting the surrounding areas from potential water-related disasters. Despite not being rated for its condition assessment, the dam's construction and design by the USDA NRCS ensure its functionality and effectiveness in managing water resources.
As a key feature in the local government's water management system, Ralston Subwatershed Site 1-2 plays a crucial role in maintaining water security and protecting the environment in the region. Its location near the TR-Little Sioux River and its capacity to store 71 acre-feet of water highlight its significance in ensuring water availability for various purposes. With state regulation and inspection in place, this dam stands as a testament to effective water resource management strategies in Iowa.
Year Completed |
1969 |
Dam Length |
429 |
Dam Height |
36 |
River Or Stream |
TR-LITTLE SIOUX RIVER |
Primary Dam Type |
Earth |
Surface Area |
2.9 |
Drainage Area |
0.4 |
Nid Storage |
71 |
Hazard Potential |
Low |
Foundations |
Soil |
Nid Height |
36 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
Little Sioux River At Correctionville
|
327cfs |
Maple River At Mapleton
|
323cfs |
West Fork Ditch At Hornick
|
80cfs |
Floyd River At James
|
187cfs |
Floyd River At Alton
|
36cfs |
Perry Creek Near Milnerville
|
25cfs |
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.
Ralston Subwatershed Site 1-2