Arch is a privately owned earth dam located in Kaycee, Wyoming, along Arch Creek. Built in 1949 for irrigation purposes, this structure stands at 30 feet high with a hydraulic height of 25 feet and a length of 258 feet. With a storage capacity of 36 acre-feet and a surface area of 6 acres, Arch serves multiple purposes including fire protection, stock maintenance, and water supply in addition to irrigation.

Despite being classified as a low hazard potential dam with fair condition assessment, Arch is regulated, permitted, inspected, and enforced by the Wyoming State Engineer's Office. The dam features an uncontrolled spillway with a width of 50 feet and an outlet gate for water release. With a moderate risk assessment rating, Arch is subject to regular inspections every 5 years to ensure its continued safety and functionality.

Located in Johnson County, Arch is part of the Omaha District under Congressional District 00, Wyoming, represented by Liz Cheney. This dam plays a crucial role in supporting agriculture and water resource management in the region, highlighting the importance of sustainable infrastructure for climate and water resource enthusiasts to monitor and protect.