Diamond, also known as Elliott #1, is a private dam located in La Salle, Weld County, Colorado. Built in 1940, this earth dam stands at a height of 26 feet and spans 650 feet in length. Its primary purpose is irrigation, with a storage capacity of 232 acre-feet and a normal storage level of 133 acre-feet. The dam is situated on the St. Vrain Creek-TR, within the jurisdiction of the Colorado Department of Water Resources.

Despite being classified as low hazard potential, Diamond has a fair condition assessment and a high risk rating of 2. While the dam does not have a spillway, it is equipped with outlet gates and undergoes regular inspections every six years. The last inspection was conducted in June 2020, ensuring its compliance with state regulations and enforcement measures. With its strategic location and contribution to irrigation in the area, Diamond serves as a critical water resource infrastructure for the surrounding agricultural community.