Monterey Lake Dam Reservoir Report

Last Updated: December 5, 2025

Monterey Lake Dam, also known as Sandy Pines Dam, is a privately owned structure located in Allegan, Michigan.


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Summary

Constructed in 1971, the dam primarily serves a recreational purpose, with a height of 20 feet and a length of 650 feet. It impounds Pigeon Creek, creating a surface area of 240 acres and a storage capacity of 2790 acre-feet.

Managed by the Michigan Department of Environment, Great Lakes, and Energy (DEGLE), Monterey Lake Dam has a high hazard potential but is currently in satisfactory condition. The dam features an uncontrolled spillway and a maximum discharge capacity of 320 cubic feet per second. Despite its moderate risk level, the dam is inspected every three years to ensure its structural integrity and compliance with regulatory standards.

Located in a picturesque setting near Hamilton, Michigan, Monterey Lake Dam provides a popular recreational spot for water and climate enthusiasts. With its serene lake and surrounding natural beauty, the dam offers a peaceful retreat for visitors seeking outdoor activities such as fishing, boating, and wildlife observation. While maintaining a balance between safety and leisure, Monterey Lake Dam stands as a testament to the importance of responsible water resource management in a changing climate.

Year Completed

1971

Dam Length

650

Dam Height

20

River Or Stream

Pigeon Creek

Primary Dam Type

Earth

Surface Area

240

Hydraulic Height

20

Drainage Area

4

Nid Storage

2790

Structural Height

20

Hazard Potential

High

Nid Height

20
       
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.