Rainbow Lake Dam Reservoir Report
Last Updated: December 22, 2025
Rainbow Lake Dam, located in Franklin County, Missouri, was completed in 1954 and serves as a recreational facility for water resource and climate enthusiasts.
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Summary
This private dam, situated on the Pin Oak Creek tributary, has a height of 27 feet and a storage capacity of 116 acre-feet. While the primary purpose of the dam is recreation, its high hazard potential highlights the importance of regular inspections and maintenance to ensure the safety of the surrounding community.
Despite being privately owned and not regulated by the state, Rainbow Lake Dam's condition assessment is currently "Not Rated," indicating a need for further evaluation. The last inspection conducted in 1980 raises concerns about the dam's structural integrity and emergency preparedness. With no Emergency Action Plan (EAP) in place, there is a lack of guidelines and procedures in case of a potential breach or disaster. Moving forward, collaboration with federal agencies and implementation of risk management measures will be crucial to safeguarding the dam and mitigating potential risks to the community and environment.
As water resource and climate enthusiasts continue to appreciate the beauty and benefits of Rainbow Lake Dam, it is imperative to prioritize safety and sustainability in its management and operation. With its historical significance and recreational value, the dam represents a vital part of Franklin County's landscape. By addressing key concerns such as hazard potential, emergency preparedness, and condition assessment, stakeholders can work together to ensure the long-term viability of Rainbow Lake Dam for future generations to enjoy.
Year Completed |
1954 |
Dam Height |
27 |
River Or Stream |
TRIB-PIN OAK CREEK |
Primary Dam Type |
Earth |
Surface Area |
8 |
Drainage Area |
160 |
Nid Storage |
116 |
Structural Height |
27 |
Hazard Potential |
High |
Foundations |
Unlisted/Unknown |
Nid Height |
27 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
Bourbeuse River At Union
|
71cfs |
Meramec River At Pacific
|
547cfs |
Big River At Byrnesville
|
174cfs |
Bonhomme Creek Near Ellisville
|
0cfs |
Meramec River Near Eureka
|
858cfs |
Kiefer Creek Near Ballwin
|
1cfs |
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.
Rainbow Lake Dam