Iowa Noname66 is a privately-owned dam located in Buena Vista, Iowa, specifically in the city of Linn Grove. Built in 1975 by the USDA NRCS, this Earth-type dam stands at 27 feet high and spans 200 feet in length. Its primary purpose is for fire protection, stock, or as a small fish pond, with a storage capacity of 42 acre-feet and a surface area of 2.5 acres. The dam is regulated by the Iowa Department of Natural Resources and undergoes state permitting, inspection, and enforcement.

Situated on TR-Cottonwood Creek, Iowa Noname66 is classified as having a low hazard potential and a moderate risk level. Despite not being rated for its condition assessment, the dam continues to serve its intended purposes effectively. While lacking certain safety features such as outlet gates and spillway width, the dam remains crucial for local water resource management. With its location in a rural area, the dam's impact on the surrounding environment and community is closely monitored by state regulatory agencies to ensure its ongoing safety and functionality.

Although Iowa Noname66 has not been updated recently and lacks certain emergency preparedness measures, its importance for fire protection and water storage cannot be understated. As a key structure in the area, it plays a vital role in maintaining water resources and supporting agricultural activities. Climate and water resource enthusiasts can appreciate the dam's significance in the local ecosystem and the efforts made by regulatory agencies to ensure its continued operation for the benefit of the community.