Coffman Dam Reservoir Report
Nearby: Wilkinson Dam Sevcik Dam
Last Updated: December 15, 2025
Coffman Dam, located in Tama, Iowa, along the TR-Iowa River, was completed in 1965 by the USDA NRCS with a primary purpose of providing fire protection and serving as a stock or small fish pond.
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Summary
The earth dam stands at a height of 26 feet with a length of 523 feet, offering a storage capacity of 83 acre-feet. While the dam has a low hazard potential, it is classified as having a moderate risk level, indicating the need for ongoing monitoring and management measures.
Managed by a private owner, Coffman Dam is regulated by the Iowa DNR and falls under state jurisdiction for permitting, inspection, and enforcement. The dam is designed to withstand normal operational conditions, with an uncontrolled spillway type in place. Despite not being rated for its current condition, the dam's risk level suggests a need for continuous assessment and potentially the development of an emergency action plan to mitigate any potential risks associated with its operation.
With its location in a rural area and serving multiple purposes beyond flood control, Coffman Dam provides valuable water resource management support for the local community. As water resource and climate enthusiasts, attention to the dam's structural integrity, maintenance, and risk management measures can help ensure the continued safety and efficiency of this vital infrastructure.
Year Completed |
1965 |
Dam Length |
523 |
Dam Height |
26 |
River Or Stream |
TR-IOWA RIVER |
Primary Dam Type |
Earth |
Surface Area |
8.1 |
Drainage Area |
0.25 |
Nid Storage |
83 |
Hazard Potential |
Low |
Foundations |
Soil |
Nid Height |
26 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
Walnut Creek Near Hartwick
|
13cfs |
Iowa River Near Belle Plaine
|
966cfs |
Richland Creek Near Haven
|
12cfs |
Salt Creek Near Elberon
|
42cfs |
Big Bear Creek At Ladora
|
55cfs |
Iowa River At Marengo
|
818cfs |
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.
Coffman Dam