Lone Star #1, also known as Alkali Reservoir, is a privately owned earth dam located in Whitewater, Colorado. Constructed in 1914 for irrigation purposes, this dam stands at a height of 47 feet and has a storage capacity of 504 acre-feet. The reservoir is fed by Alkali Creek and covers an area of 7 acres, serving as a vital water resource in the region.

Despite its low hazard potential, Lone Star #1 has been assessed as unsatisfactory in terms of condition, with a high risk assessment rating of 2. The dam's last inspection took place in March 2017, with a recommended inspection frequency of every 6 years. The outlet gates consist of uncontrolled and valve mechanisms, and the spillway type is listed as "None."

Water resource and climate enthusiasts interested in the management and maintenance of dams will find Lone Star #1 a fascinating case study in the intersection of private ownership and state regulation. With its long history of serving agricultural needs in the region, this dam presents a unique blend of challenges and opportunities for sustainable water resource management in Colorado.