Margaret-Carpenter is a locally owned dam located in Thornton, Colorado, along the Grange Hall Creek. Built in 2008, this earth dam stands at a height of 20 feet and serves primarily for irrigation purposes, with additional benefits for recreation. With a storage capacity of 105 acre-feet, the dam covers a surface area of 10 acres and has a drainage area of 1 square mile. The spillway, which is uncontrolled, has a width of 102 feet, allowing for a maximum discharge of 1986 cubic feet per second.

Managed by the local government, Margaret-Carpenter has been regulated and permitted by the Colorado Department of Water Resources. Despite its low hazard potential, the dam undergoes regular inspections every six years, with the latest assessment in April 2019 deeming its condition as satisfactory. With a moderate risk assessment rating of 3, the dam's risk management measures and emergency action plan are yet to be fully documented and updated. Overall, Margaret-Carpenter serves as a vital water resource for the community while adhering to strict regulatory guidelines to ensure public safety and environmental sustainability.