Apple River
Apple River is a masonry dam located in St. Croix County, Wisconsin, built in 1954. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Apple River
The primary purpose of Apple River is hydroelectric. The dam generates hydroelectric power by channeling water through turbines, converting the energy of flowing water into electricity. The dam is owned by Northern States Power Co (public utility). It impounds the Apple River near Stillwater, Mn.
The dam stands 47 feet tall, creates a reservoir covering 52 acres, has a maximum storage capacity of 668 acre-feet, and collects water from a drainage area of 555 square miles. Completed in 1954, the structure is well into its service life at over 50 years old.
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 05/24/2022.
At 47 feet, this dam is taller than 92% of dams nationwide.
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.
Location
| State | Wisconsin |
| County | St. Croix |
| Nearest City | Stillwater, Mn |
| River/Stream | Apple River |
| Coordinates | 45.15780, -92.71600 |
Physical Characteristics
| Dam Type | Masonry |
| NID Height | 47 ft |
| Dam Height | 47 ft |
| Year Completed | 1954 (72 years old) |
Storage & Hydraulics
| NID Storage | 668 acre-ft |
| Max Storage | 668 acre-ft |
| Normal Storage | 668 acre-ft |
| Surface Area | 52 acres |
| Drainage Area | 555 sq mi |
| Max Discharge | 9,000 cfs |
| Spillway Type | Controlled |
Ownership & Safety
| Purpose | Hydroelectric |
| Owner | Northern States Power Co |
| Owner Type | Public Utility |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 05/24/2022 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | WI00027 |
| Federal ID | WI00027 |
| More Info | State Dam Safety Program |