New Richmond Mills

New Richmond Mills is a gravity dam located in St. Croix County, Wisconsin, built in 1812. It carries a High hazard potential classification and has a satisfactory condition assessment.

About New Richmond Mills

The primary purpose of New Richmond Mills is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by City Of New Richmond (local government). It impounds the Willow River near New Richmond.

The dam stands 19 feet tall and stretches 325 feet across, creates a reservoir covering 236 acres, has a maximum storage capacity of 1,500 acre-feet, and collects water from a drainage area of 146 square miles. Completed in 1812, the structure is one of the older dams in the region, with over a century and a half of service.

This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. Its condition is rated satisfactory, indicating no existing or potential dam safety deficiencies are recognized. An emergency action plan is in place for this dam. The most recent inspection on record was 08/10/2021.

Living Downstream

If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The Wisconsin dam safety program can provide more specific information about emergency planning for this structure.

Search for dams near your address to see all dams in your area with hazard classifications and safety data.

High HazardSatisfactory ConditionEmergency Action Plan: Yes

Location

StateWisconsin
CountySt. Croix
Nearest CityNew Richmond
River/StreamWillow River
Coordinates45.12285, -92.53899

Physical Characteristics

Dam TypeGravity
NID Height19 ft
Dam Height19 ft
Dam Length325 ft
Year Completed1812 (214 years old)

Storage & Hydraulics

NID Storage1,500 acre-ft
Max Storage1,500 acre-ft
Normal Storage826 acre-ft
Surface Area236 acres
Drainage Area146 sq mi
Max Discharge4,600 cfs
Spillway TypeControlled

Ownership & Safety

PurposeRecreation
OwnerCity Of New Richmond
Owner TypeLocal Government
Hazard ClassificationHigh
Condition AssessmentSatisfactory
Last Inspection08/10/2021
Emergency Action PlanYes

Identifiers

NID IDWI00188
Federal IDWI00188
More InfoState Dam Safety Program

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