West Branch Flood Control Dam Reservoir Report

Last Updated: December 6, 2025

The West Branch Flood Control Dam, located in West Branch, Iowa, was completed in 2012 with the primary purpose of flood risk reduction.


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Summary

This earth dam, standing at 24 feet in height and 600 feet in length, plays a crucial role in protecting the surrounding area from potential flooding events. Designed by French Reneker Associates Inc., the dam is regulated by the Iowa Department of Natural Resources and undergoes regular inspections to ensure its structural integrity.

With a storage capacity of 111 acre-feet and a maximum discharge rate of 3410 cubic feet per second, the West Branch Flood Control Dam provides essential flood protection for the community. Despite its high hazard potential, the dam's condition is assessed as satisfactory, ensuring its readiness to respond to potential emergencies. The dam serves as a critical infrastructure asset in mitigating flood risks and safeguarding the local environment against the impacts of extreme weather events, demonstrating the importance of effective water resource management and climate resilience efforts in the region.

Managed by local government authorities, the West Branch Flood Control Dam stands as a testament to the collaborative efforts of state and federal agencies in enhancing flood resilience. With its strategic location in Johnson County, Iowa, the dam serves as a vital component of the region's flood control infrastructure, showcasing the commitment to safeguarding communities and ecosystems from the threats of climate change. As water resource and climate enthusiasts, the West Branch Flood Control Dam stands as a symbol of proactive risk management and sustainable development practices in the face of evolving environmental challenges.

Year Completed

2012

Dam Length

600

Dam Height

24

Primary Dam Type

Earth

Hydraulic Height

24

Drainage Area

0.49

Nid Storage

111

Structural Height

24

Hazard Potential

High

Foundations

Soil

Nid Height

24
       
Seasonal Comparison

Weather Forecast

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. 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

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, 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.