Heimos Lake Dam Reservoir Report

Last Updated: December 5, 2025

Heimos Lake Dam, also known as Pierce Lake Dam, is a privately owned structure located in Richwoods, Missouri.


°F

°F

mph

Wind

%

Humidity

Summary

Completed in 1955, this rockfill dam stands at a height of 37 feet and has a length of 1350 feet, creating a reservoir with a storage capacity of 610 acre-feet. The primary purposes of this dam are fire protection, stock, and small fish pond management, serving as a vital resource for the local community.

With a high hazard potential and a satisfactory condition assessment, Heimos Lake Dam is regulated and inspected by the Dam and Reservoir Safety Program in Missouri. The dam poses a moderate risk, and emergency action plans are in place to ensure the safety of surrounding areas in the event of a breach or failure. The dam's spillway, with a width of 60 feet, helps to control water flow and prevent overflow during periods of heavy rainfall.

Water resource and climate enthusiasts will find Heimos Lake Dam to be an intriguing structure that plays a crucial role in maintaining water resources in the Washington County area. Its construction and management reflect the importance of proper dam regulation and inspection to ensure public safety and protect the surrounding environment. With its unique design and history, Heimos Lake Dam stands as a testament to the intersection of human engineering and natural resource management.

Year Completed

1955

Dam Length

1350

Dam Height

37

River Or Stream

TRIB-LITTLE INDIAN CREEK

Primary Dam Type

Rockfill

Surface Area

35

Drainage Area

200

Nid Storage

610

Structural Height

37

Outlet Gates

None

Hazard Potential

High

Foundations

Unlisted/Unknown

Nid Height

37
       
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.