Chevally Reservoir, located in Malheur, Oregon, is a privately owned earth dam structure that was completed in 1933 for irrigation purposes along Cow Creek. With a capacity of 406 acre-feet, this reservoir covers a surface area of 60 acres and serves as a vital water resource for the surrounding area. The dam stands at 22 feet high and has a structural height of 30 feet, providing essential water storage for agricultural needs in the region.

Managed by the Oregon Water Resources Department, Chevally Reservoir is regulated, inspected, and enforced to ensure its safety and functionality. Despite being classified as having low hazard potential, regular inspections are conducted every six years to maintain its condition and assess any potential risks. The reservoir's emergency action plan status, risk assessment, and inundation maps are currently not specified, but the structure is designed to meet irrigation demands efficiently while adhering to regulatory guidelines.

With its strategic location and historical significance in supporting irrigation activities, Chevally Reservoir remains a crucial water management infrastructure in the area. The reservoir's presence contributes to the sustainable use of water resources for agricultural purposes and underscores the importance of proper dam maintenance and oversight to ensure the safety and reliability of water supply systems in the region.