Forest Dunes Lake Dam Reservoir Report

Last Updated: December 5, 2025

Forest Dunes Lake Dam, located in Mio, Michigan, is a private dam primarily used for recreation purposes.


°F

°F

mph

Wind

%

Humidity

Summary

Completed in 1999, this earth-type dam stands at a height of 25.3 feet and has a storage capacity of 370 acre-feet. It is situated on an unnamed tributary to Thayer Creek, with a drainage area of 1 square mile.

The dam's spillway type is uncontrolled, with a width of 2 feet, and it has a low hazard potential with a satisfactory condition assessment. Despite being regulated by the Michigan Department of Environment, Great Lakes, and Energy (DEGLE), the dam has not been modified in recent years and is regularly inspected every 5 years. The risk assessment for Forest Dunes Lake Dam is moderate, indicating potential risks that are being managed to ensure the safety of the surrounding community and the environment. Water resource and climate enthusiasts will find this dam an interesting site to study and monitor for its impact on the local ecosystem and water resources.

Year Completed

1999

Dam Length

1200

Dam Height

25.3

River Or Stream

Unnamed Trib to Thayer Creek

Primary Dam Type

Earth

Surface Area

28

Hydraulic Height

21

Drainage Area

1

Nid Storage

370

Structural Height

25.3

Hazard Potential

Low

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.