The Hg Armbruster Group is a privately owned dam located in Pierce, Wisconsin, designed by the USDA NRCS in 1962. This earth dam, with a height of 29 feet and a length of 308 feet, serves multiple purposes including fire protection and providing water for stock or small fish ponds. It is regulated by the Wisconsin Department of Natural Resources and has state permitting, inspection, and enforcement in place.

Situated on a tributary to the Trimbelle River, the Hg Armbruster Group dam has a low hazard potential and is currently rated as "Not Rated" in terms of its condition assessment. This dam has a storage capacity of 47 acre-feet, with a normal storage level of 9 acre-feet and a maximum discharge of 245 cubic feet per second. While the risk assessment for this dam is considered very high, it has not yet been assigned a Dam Safety Action Classification (DSAC) date.

Overall, the Hg Armbruster Group dam is an essential structure for fire protection and water resource management in the area. With its controlled spillway and state-regulated status, this dam plays a crucial role in ensuring water availability for various purposes while adhering to safety and regulatory standards. For water resource and climate enthusiasts, this dam serves as a significant example of responsible water infrastructure management in Wisconsin.