Reynolds No. 1 is a privately owned irrigation dam located in Wyoming, specifically in Sheridan County near the city of Wyola, MT. Built in 1972, this earth dam stands at a height of 46 feet and serves the primary purpose of irrigation, with a storage capacity of 889 acre-feet. The dam spans 1000 feet in length and is situated on Twin Creek, under the jurisdiction of the State Engineer's Office.

Despite being classified as having a low hazard potential, Reynolds No. 1 is in poor condition as of its last assessment in 2017. The dam's spillway is uncontrolled, with a width of 15 feet, and it lacks outlet gates. While the risk assessment indicates a moderate level of risk, there are no specific risk management measures identified for this structure. With its location in a picturesque setting and its essential role in providing irrigation water, Reynolds No. 1 is a significant water resource feature that warrants attention and potential improvements to ensure its continued functionality and safety.