Box I #1, also known as Box Eye #1, is a privately owned irrigation dam located in Larimer County, Colorado. Completed in 1967, this earth dam stands at a height of 18 feet and has a storage capacity of 200 acre-feet. The dam serves the primary purpose of irrigation, with a normal storage capacity of 108 acre-feet and a maximum discharge of 2354 cubic feet per second into the Boxelder Creek.

Despite being classified as having a low hazard potential and fair condition assessment, Box I #1 is regulated by the Colorado Department of Water Resources. The dam features an uncontrolled spillway with a width of 168 feet, helping to manage excess water during periods of high flow. The last inspection of the dam took place in September 2015, with an inspection frequency of 6 years and a moderate risk assessment rating.

Located 6 miles from Wellington, Colorado, Box I #1 plays a crucial role in the local water resource management system. With its strategic placement on the Boxelder Creek, this dam provides vital irrigation water for agricultural activities in the surrounding area. Climate and water resource enthusiasts will find Box I #1 to be an intriguing example of how infrastructure plays a key role in sustaining water availability in arid regions like Colorado.