The combined storage levels of Lake Powell and Lake Mead have dropped to a level not seen since 1956, according to a new research paper authored by Colorado River scholars. The record low marks a grim milestone for the nation's two largest reservoirs, which hold nearly 60% of all water stored within the Colorado River system.
Unprecedented Reservoir Depletion
Jack Schmidt, the director of the Center for Colorado River Studies at Utah State University, described the current water levels as both humbling and potentially disturbing. Schmidt noted that the amount of $\text{water}$ currently in the reservoirs is lower than what was held before Lake Powell even existed during the construction of the Glen Canyon Dam.
Basin Dynamics and Usage
Data from the Bureau of Reclamation shows that as of July 12, Lake Mead was at 27% capacity while Lake Powell sat at 24%. Schmidt explained that the two reservoirs function essentially as one massive reservoir divided by Grand Canyon National Park, with Powell situated downstream of significant Upper Basin uses and Mead located upstream of significant Lower Basin uses.
The Upper Basin encompasses Utah, Colorado, New Mexico, and Wyoming, while the Lower Basin includes Arizona, California, and Nevada.
Challenges in Water Management
The record lows have prompted intense debate regarding the future of reservoir management. Schmidt suggested that while the current levels raise questions about which reservoirs are necessary, he expressed doubt that water managers are prepared for such discussions because they currently struggle to reach a consensus on sharing the river's resources.
He further noted that functional conversations regarding how to reduce consumptive use have yet to be established among the seven states that share the Colorado River.
Ongoing Interstate Negotiations
Negotiations are ongoing as current management guidelines are set to expire at the end of this year. Gene Shawcroft, Utah’s Colorado River negotiator, told The Tribune that states met last week and more meetings were anticipated during the week of July 22. Shawcroft added that the two basins have begun exchanging previously unshared draft agreements that they had been developing separately with the federal government.
Infrastructure and Flow Management
The Bureau of Reclamation is under pressure to establish operating plans before the water year begins at Lake Powell on October 1. The agency is also expected to release a final environmental impact statement later this month.
To maintain Lake Powell above critical elevation levels following a record dry and warm winter, Reclamation has been reducing flows from the Glen Canyon Dam and increasing releases from Flaming Gorge. However, Schmidt noted via email that while May releases from Flaming Gorge provided a temporary boost, the reservoir began dropping again after June 1, and current releases are only slowing the recession rather than increasing storage.
Risks to Dam Infrastructure
The decline in water levels poses significant risks to dam infrastructure. Katrina Grantz, Reclamation’s deputy director for the Upper Colorado Region, stated in June that if levels fall below 3,500 feet, documented damage to the Glen Canyon Dam infrastructure occurs. If levels drop below 3,490 feet, the dam can no longer generate hydropower, forcing the agency to use lower outlets not intended for long-term operation.
Eric Balken, executive director of the Glen Canyon Institute, argued that the current strategy is effectively sacrificing Lake Mead and Flaming Gorge to prop up Lake Powell. He suggested that decision makers must consider 'outside the box' solutions, such as re-engineering infrastructure at the dam.
The Future of the Basin
Despite proposals from groups like the Glen Canyon Institute to 'Fill Mead First,' Grantz stated she could not speculate on decades-long future outcomes, though she emphasized that these reservoirs remain vital resources that prevented a crisis years ago.
Shawcroft remains cautious about abandoning a single-reservoir model, noting that modifying the dam would not solve the fundamental 'math problem' of consumption exceeding supply. Meanwhile, Reclamation forecasts suggest Lake Powell could drop below 3,500 feet by the end of February 2027.
