The Bureau of Reclamation has released its annual operating conditions report for Lake Powell and Lake Mead, which offered a mixed assessment of the Colorado River.
But some conservationists have called for a hard look at how the Glen Canyon Dam is managed.
Last winter’s above-average rain and snowfall came as a welcome relief, the Bureau said, but the nation’s largest reservoirs - Lake Powel and Lake Mead - remain at historic lows.
Eric Balken, of the Glen Canyon Institute, says that climate change will continue to drain the system.
"So, even after these most Biblical of snow years, the system is only 35% full," Balken said. "The problem is not solved, and it’s probably going to get worse," he said.
The Bureau has begun a Supplemental Environmental Impact Statement that could change how it manages the river and Glen Canyon Dam in the future.
Balken says the Bureau should put its efforts into filling Lake Mead and use Lake Powell as a backup.