Giffin #2 (Upper) is a privately owned earth dam located in Weld County, Colorado, along the Lone Tree Creek. Built in 1952 for irrigation purposes, this dam stands at a height of 21 feet and has a storage capacity of 155 acre-feet. With a normal storage level of 91 acre-feet, the dam covers a surface area of 15 acres and serves a drainage area of 56 square miles.

Despite its low hazard potential and satisfactory condition assessment, Giffin #2 (Upper) is subject to state regulation, permitting, inspection, and enforcement by the Colorado Division of Water Resources. The dam features an uncontrolled spillway with a width of 187 feet, capable of discharging up to 4590 cubic feet per second in case of overflow. The last inspection of the dam was conducted in April 2016, with a moderate risk assessment rating of 3.

Located in the city of Nunn, Colorado, Giffin #2 (Upper) plays a crucial role in the local irrigation system, providing water for agricultural activities in the region. As a key infrastructure for water resource management, this dam represents a significant aspect of Colorado's water conservation and utilization efforts. Enthusiasts of water resources and climate will appreciate the engineering details and operational significance of Giffin #2 (Upper) in sustaining the water needs of the surrounding community.