Loon Lake, located in Cass County, Minnesota, is a federally owned Earth dam constructed in 1969 by the USDA FS with a primary purpose that falls under the "Other" category. This dam stands at a height of 7 feet and spans 180 feet in length, with a storage capacity of 530 acre-feet. The reservoir's normal storage level is reported to be 370 acre-feet and serves a drainage area of 0.96 square miles, with a low hazard potential and a condition assessment that is currently "Not Rated."

Managed by the St. Paul District of the US Army Corps of Engineers, the dam has not undergone any modifications since its completion and has not been inspected since March 1974. Despite its age, the structure has not been assessed for its current condition, and no emergency action plan or inundation maps have been prepared. The dam poses a low risk due to its condition and hazard potential, but without a recent evaluation, there is uncertainty about its current safety and resilience in the face of potential climate challenges and water resource management issues.

As an integral part of the Willow River watershed, Loon Lake plays a crucial role in water storage and management in the region. Water resource and climate enthusiasts would find Loon Lake an intriguing case study for understanding the complexities of dam infrastructure, federal ownership, and the need for regular inspections and risk assessments to ensure the safety and reliability of critical water resources in Minnesota.