Grand Rapids Reservoir Report

Last Updated: December 5, 2025

Grand Rapids, located in Marinette, Wisconsin, is a gravity dam built along the Menominee River in 1909 for hydroelectric power generation and recreation purposes.


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Summary

Designed by L.A. DeGuere, this dam stands at a height of 24 feet with a hydraulic height of 28 feet and a structural height of 28.5 feet. It has a length of 1410 feet and a storage capacity of 2150 acre-feet, serving as a vital water resource in the region with a maximum discharge of 42000 cubic feet per second.

Operated by a public utility, Grand Rapids is regulated by the Federal Energy Regulatory Commission (FERC) and has a controlled spillway with a width of 402 feet. The dam's hazard potential is classified as high, with a very high risk assessment rating. The dam's condition assessment is not available, but it undergoes regular inspections with an inspection frequency of 1. In case of emergencies, an emergency action plan is in place, meeting safety guidelines and ensuring proper risk management measures.

With its historical significance and crucial role in water resource management and energy production, Grand Rapids serves as a key landmark in the region. As a major contributor to the local economy and environment, this dam continues to play a vital role in supporting the community's water needs and providing recreational opportunities along the Menominee River. Its rich history, engineering marvel, and environmental impact make Grand Rapids a must-visit destination for water resource and climate enthusiasts alike.

Year Completed

1909

Dam Length

1410

Dam Height

24

River Or Stream

Menominee River

Primary Dam Type

Gravity

Surface Area

300

Hydraulic Height

28

Drainage Area

3720

Nid Storage

2150

Structural Height

28.5

Outlet Gates

Tainter (radial) - 15

Hazard Potential

High

Foundations

Rock

Nid Height

29
       
Seasonal Comparison

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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.