John Keys told the Colorado River Water Users Association here that the bureau is developing "worst-case scenarios" should the current six-year drought persist. And among those scenarios are water allocation reductions from Lake Powell, perhaps as early as 2006, and from Lake Mead in early 2007. Mexico's water take beyond the 1.5 million acre-feet it receives as part of the Colorado Compact could be put on the table as well.

"What I must emphasize is that this is only an example of the trade-offs we will have to make," Keys told the group, which wrapped up two days of meetings on Friday. "You all have an interest in how these issues are resolved, in a way that meets the needs of the entire [Colorado River] basin, while also following the Law of the River."

Keys says he is not trying to sound too alarmist.

"It's not a crisis yet," he said. "The reservoirs are half-full. But it is time to start transitioning to low-end operations."

To begin managing the Colorado, in other words, as if in the midst of a much longer drought, rather than hoping the typical five-year dry cycle is on the verge of ending.

To that end, Bureau of Reclamation researchers have assembled data from what has been the longest dry stretch in bureau history - a 12-year span from 1953-64 - and welding it onto numbers from the current drought.

And this, Keys says, is where the trade-offs come in. Should this drought persist, choices will have to be made, particularly in terms of Lake Powell and Lake Mead.

"Do we protect our power resources? Our water resources? At Powell? At Mead? At both," said the commissioner.

Put simply, do you cut water allotments out of Lake Powell and Lake Mead to preserve the hydroelectric capacity of Glen Canyon and Hoover Dam? Or do you reduce power to preserve water allotments?

Current bureau modeling, Keys says, prevents both reservoirs from dipping below current power generating standards. But that also means that water deliveries would be curtailed earlier than currently planned.

Sure, things could turn around, he told the audience. A cool summer and wet fall have given rise to hopes that the drought stranglehold may soon be broken.

Best case scenario?

"If we had a couple years like 1983-84, we'll get back to 90 percent of storage capacity, but that's not likely," Keys said. "The likelihood is that this will be a much slower process [of recovery], at least in part because of growth. But I do believe we will be able to meet our obligations in the coming years.

Still, Keys added, "We will prepare for the worst and hope for the best. But hope is not a strategy in dealing with this situation."

jbaird@sltrib.com