Shea Reservoir Report

Last Updated: December 5, 2025

Shea, also known as New Fisher Lake, is a gravity dam located in Iron, Wisconsin, with a primary purpose of recreation.


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Summary

Completed in 1912, this dam stands at a height of 10.5 feet and has a hydraulic height of 4.5 feet. It has a normal storage capacity of 2250 acre-feet and a maximum discharge of 1575 cubic feet per second. The dam's spillway is controlled, and it has a surface area of 452 acres within a drainage area of 60 square miles.

Despite being classified as having a low hazard potential, Shea's condition assessment is fair as of May 2020. The dam has been inspected every 10 years, with the last inspection conducted in July 2013. It is regulated by the Wisconsin Department of Natural Resources and meets state permitting, inspection, and enforcement requirements. With a risk assessment rating of very high (1), Shea's risk management measures and inundation maps prepared status are not specified in the data. Overall, Shea presents an interesting case study for water resource and climate enthusiasts, showcasing the intersection of infrastructure, regulation, and risk assessment in dam management.

Years Modified

1937 - Other

Year Completed

1912

Dam Length

43

Dam Height

10.5

River Or Stream

TURTLE

Primary Dam Type

Gravity

Surface Area

452

Hydraulic Height

4.5

Drainage Area

60

Nid Storage

3600

Structural Height

10.5

Hazard Potential

Low

Nid Height

11
       
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.