Lower Hackett Dam, also known as Red Reservoir, is a gravity dam located in Natrona, Wyoming, along Hackett Creek. Owned and regulated by the Bureau of Land Management, this federal structure serves the primary purpose of debris control. Completed in 1967, the dam stands at a structural height of 37 feet and has a hydraulic height of 33 feet, with a length of 1052 feet. It has a storage capacity of 171 acre-feet and a normal storage level of 43 acre-feet, covering a surface area of 15.2 acres with a drainage area of 10.31 square miles.

Despite its low hazard potential, Lower Hackett Dam has been assessed as unsatisfactory in condition, with a moderate risk level. The dam is equipped with an uncontrolled spillway and has no outlet gates. It has undergone inspections every five years, with the most recent inspection conducted in July 2017. The structure has not been modified since its completion, and there are no associated locks or lock structures. While the dam does not fall under the jurisdiction of the US Army Corps of Engineers, it remains a crucial component in managing water resources and mitigating potential risks in the region.