Margaret, a private dam located in Arvada, Wyoming, was designed by Clifford J Sanders in 1966 for purposes of fire protection, stock, and a small fish pond. The earth dam stands at a height of 33 feet with a hydraulic height of 18 feet and a structural height of 33 feet. It has a length of 625 feet and a storage capacity of 145 acre-feet. The dam, situated on the West Fork Antelope Creek, serves as a low hazard potential structure with a fair condition assessment.

This dam, regulated by the Wyoming State Engineer's Office, is inspected every five years to ensure its safety and functionality. Despite its uncontrolled spillway type and lack of outlet gates, Margaret has shown moderate risk potential (rating of 3) with no significant modifications or emergency action plans in place as of the last assessment in May 2018. The dam's location in Johnson County, Wyoming, under the jurisdiction of the state regulatory agency, highlights its importance for fire protection and water resource management in the area.

For water resource and climate enthusiasts, Margaret presents an intriguing case study of a privately owned dam designed over five decades ago to serve multiple purposes in a rural setting. Its association with the West Fork Antelope Creek and the Omaha District of the USACE underscores the interconnectedness of water management infrastructure in the region. As climate change impacts water availability and safety, understanding the condition and risks associated with structures like Margaret is crucial for sustainable water resource management and disaster preparedness efforts in Wyoming and beyond.