South Zumbro Wr-4
South Zumbro Wr-4 is an earth dam located in Olmsted County, Minnesota, built in 1988. It carries a High hazard potential classification and has a satisfactory condition assessment.
About South Zumbro Wr-4
The primary purpose of South Zumbro Wr-4 is flood risk reduction. The dam is designed to control downstream flooding by temporarily storing excess water during storms and releasing it at a controlled rate. The dam is owned by City Of Rochester (local government). It impounds the Willow Creek-tr near Rochester.
The dam stands 46 feet tall and stretches 1,100 feet across, creates a reservoir covering 40 acres, has a maximum storage capacity of 968 acre-feet, and collects water from a drainage area of 4 square miles. Completed in 1988, the structure is 38 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 10/15/2024.
At 46 feet, this dam is taller than 91% 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 Minnesota 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 | Minnesota |
| County | Olmsted |
| Nearest City | Rochester |
| River/Stream | Willow Creek-tr |
| Coordinates | 43.94982, -92.43598 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 46 ft |
| Dam Height | 21 ft |
| Dam Length | 1,100 ft |
| Year Completed | 1988 (38 years old) |
Storage & Hydraulics
| NID Storage | 968 acre-ft |
| Max Storage | 968 acre-ft |
| Normal Storage | 331 acre-ft |
| Surface Area | 40 acres |
| Drainage Area | 4 sq mi |
| Max Discharge | 140 cfs |
| Spillway Type | Controlled |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | City of Rochester |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 10/15/2024 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | MN00991 |
| Federal ID | MN00991 |
| More Info | State Dam Safety Program |