Nsp-Bottom Ash, also known as Sherco Ash Pond, is a dam located in Sherburne, Minnesota, owned by the public utility NSP. Constructed in 1983, this Earth dam stands at a height of 35 feet and has a storage capacity of 200 acre-feet. The dam serves a primary purpose of "Other" and is regulated by the Minnesota Department of Natural Resources (MNDNR EWR).

Situated near the Mississippi River, Nsp-Bottom Ash presents a low hazard potential with a satisfactory condition assessment. Despite its low risk level, the dam has been classified as having a very high risk due to its location and characteristics. The last inspection was conducted in November 2017, with an inspection frequency of 8 years. The dam's emergency action plan status, inundation maps, and risk management measures are not currently available.

Overall, Nsp-Bottom Ash is a crucial structure for water resource management in the area, providing storage capacity and flood control along the Mississippi River. With its controlled spillway and satisfactory condition, this dam plays a vital role in protecting the surrounding community from potential water-related risks and emergencies.