Dissolved oxygen estimates were generated to help understand how different alternative management scenarios may affect the likelihood of low dissolved oxygen in Glen Canyon Dam releases. The study aimed to examine the effects of different management alternatives on late summer and early fall dissolved oxygen concentrations in Glen Canyon Dam releases. The estimates represent estimates of dissolved oxygen concentration in Glen Canyon Dam releases between August and October of a given year. These estimates were generated using data collected in Lake Powell reservoir as part of a long-term inter-agency water quality monitoring program conducted by the Bureau of Reclamation, the National Park Service, and the U.S. Geological Survey. Specifically, the dissolved oxygen concentration in dam releases was modeled based on alternative hydrologies associated with alternatives under both the Near-term Colorado River Operations Supplemental Environmental Impact Statement (Interim Guidelines sEIS) and the Glen Canyon Dam Long-Term Experimental and Management Plan Supplemental Environmental Impact Statement (LTEMP sEIS). These estimates can be used to examine how different proposed alternative management strategies may affect oxygen concentrations in Glen Canyon Dam releases.