Nsp-bottom Ash
Nsp-bottom Ash is an earth dam located in Sherburne County, Minnesota, built in 1983. It carries a Significant hazard potential classification and has a satisfactory condition assessment.
About Nsp-bottom Ash
The primary purpose of Nsp-bottom Ash is tailings. Tailings dams contain waste material from mining operations — typically a slurry of finely ground rock left over after valuable minerals have been extracted. These structures require ongoing monitoring because tailings can contain heavy metals and other contaminants. The dam is owned by Xcel Energy (public utility). It impounds the Mississippi River - Os near Monticello.
The dam stands 35 feet tall and stretches 500 feet across, creates a reservoir covering 10 acres, and has a maximum storage capacity of 200 acre-feet. Completed in 1983, the structure is 43 years old.
This dam has a significant hazard potential classification, meaning that a failure could cause significant economic damage — flooding roads, bridges, or property downstream — but is not expected to result in loss of life. Its condition is rated satisfactory, indicating no existing or potential dam safety deficiencies are recognized. The most recent inspection on record was 11/07/2017.
At 35 feet, this dam is taller than 82% of dams nationwide.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | Minnesota |
| County | Sherburne |
| Nearest City | Monticello |
| River/Stream | Mississippi River - Os |
| Coordinates | 45.37479, -93.89138 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 35 ft |
| Dam Height | 35 ft |
| Dam Length | 500 ft |
| Year Completed | 1983 (43 years old) |
Storage & Hydraulics
| NID Storage | 200 acre-ft |
| Max Storage | 200 acre-ft |
| Normal Storage | 50 acre-ft |
| Surface Area | 10 acres |
| Max Discharge | 2 cfs |
| Spillway Type | Controlled |
Ownership & Safety
| Purpose | Tailings |
| Owner | Xcel Energy |
| Owner Type | Public Utility |
| Hazard Classification | Significant |
| Condition Assessment | Satisfactory |
| Last Inspection | 11/07/2017 |
| Emergency Action Plan | Not Required |
Identifiers
| NID ID | MN00980 |
| Federal ID | MN00980 |
| More Info | State Dam Safety Program |