Upper Horicon Reservoir Report

Last Updated: December 5, 2025

Upper Horicon, also known as Pool One, is a federal-owned water resource located in Horicon, Dodge County, Wisconsin.


°F

°F

mph

Wind

%

Humidity

Summary

This recreational dam on the Main Ditch was completed in 1945 and stands at a height of 8 feet with a length of 21,700 feet. With a storage capacity of 1,600 acre-feet and a surface area of 320 acres, it serves as a popular spot for water and climate enthusiasts to enjoy outdoor activities.

Managed by the Wisconsin Department of Natural Resources, Upper Horicon is regulated, permitted, inspected, and enforced by state agencies to ensure its safety and compliance. The dam's hazard potential is rated as low, but its risk assessment indicates a very high risk level, signaling the need for proactive risk management measures. While the dam's condition assessment is labeled as "Not Rated," its emergency action plan status, inundation maps, and risk management measures are currently not documented.

Overall, Upper Horicon offers a picturesque setting for recreation and relaxation, with opportunities for boating, fishing, and wildlife observation. As a vital part of the water resource infrastructure in Wisconsin, it serves as a reminder of the importance of maintaining and managing our natural resources in the face of changing climate conditions.

Year Completed

1945

Dam Length

21700

Dam Height

8

River Or Stream

MAIN DITCH

Primary Dam Type

Earth

Surface Area

320

Hydraulic Height

1

Drainage Area

220

Nid Storage

1600

Structural Height

8

Hazard Potential

Low

Nid Height

8
       
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.