Tim Seim Dam Reservoir Report

Last Updated: December 6, 2025

Tim Seim Dam, located in Tama, Iowa, is a privately owned structure designed by USDA NRCS to serve as a grade stabilization measure along a tributary of the Iowa River.


°F

°F

mph

Wind

%

Humidity

Summary

Completed in 2017, this earth dam stands at a height of 25 feet and spans a length of 390 feet, with a storage capacity of 67 acre-feet. The dam primarily serves the purpose of grade stabilization and has a low hazard potential.

Despite being privately owned, Tim Seim Dam is regulated by the Iowa Department of Natural Resources, with state permitting, inspection, and enforcement in place. The dam is situated in a rural area with a surface area of 4 acres and a drainage area of 0 acres. With a maximum discharge capacity of 93 cubic feet per second, the dam features a spillway width of 16 feet. While the dam's condition assessment is currently not rated, it meets the necessary guidelines for emergency action planning and risk management measures.

Water resource and climate enthusiasts will be intrigued by the engineering design and environmental impact of Tim Seim Dam. As a vital infrastructure for mitigating erosion and stabilizing the local water system, this privately owned structure showcases the collaboration between federal agencies and state regulators. With its completion in 2017, the dam serves as a model for sustainable water management practices in the region, highlighting the importance of maintaining and monitoring such critical infrastructure for long-term environmental resilience.

Year Completed

2017

Dam Length

390

Dam Height

25

River Or Stream

Tributary of the Iowa River

Primary Dam Type

Earth

Surface Area

4

Nid Storage

67

Hazard Potential

Low

Foundations

Soil

Nid Height

25
       
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.