How Colorado River Levels Stand as U.S. Mulls Plan for Failure

The Colorado River, which provides water for 40 million people, is flowing at some of the lowest levels ever seen amid a severe drought that has been gripping the southwest for decades.

Over the last century, the river's flow has dropped by 20 percent, according to data from the U.S. Geological Survey. That means that its reservoirs, like Lake Mead and Lake Powell, are dropping far below their full capacity.

As of April 12, Lake Mead's levels were at 1,046.41 feet, only about 30 percent of its full capacity, while Lake Powell was at a historic low of 3,520.11 feet as of April 11.

Heavy local water consumption and the lingering extremely dry conditions have meant that the river's water is being used faster than it can be replenished. The Colorado River's flow is now so low that it has triggered the U.S. Bureau of Reclamation to propose a plan in case drastic measures need to be taken.

If the situation continues to worsen, the reservoirs could hit dead pool level, which means that hydropower operations would cease.

Consequently, the Bureau on April 11 announced two possible separate plans to make drastic water cuts. The Bureau's main goal is to conserve enough water so that the Hoover and Glen Canyon Dams, which form Lake Mead and Lake Powell, continue to produce hydropower.

Both plans come with their own sets of implications for Colorado River basin states, which include Arizona, California, New Mexico, Colorado, Utah, Nevada and Wyoming.

The first option is based on the priority of water rights. This means water conservation cuts would be based around those who rely on the water most.

The second option is based off a "same percentage" approach. That would see water cuts being spread across the basin states equally. Under this approach, all cities, native tribes and irrigators would need to adhere to the same reductions.

There is also the third option of doing nothing.

Edith Zagona, a research professor of water resources engineering at the University of Colorado Boulder, told Newsweek that the final policy actually implemented could still be different from any of these options.

"There is now a good snow pack, promising a good runoff this year, but that does not change the fact that Reclamation needs a policy in place that will allow them to protect the reservoirs in the future, regardless of what this year and future years' inflows look like."

The alternative options are also "two extremes," Zagona said.

"The priority approach holds to historical agreements that respect California's highest priority on the river. This would spare them cuts until the juniors - Arizona and Nevada - have had all or most of their deliveries cut. Because they both have small allocations compared to California, this would be quite difficult - cutting water to Las Vegas, Phoenix and Tucson, and also tribes. California's cuts would be less painful," Zagona said.

"The 'share the shortage' approach that would reduce all the states equally by percentage of their allocation would spread the pain of reductions. This may still be painful for all the states, but would not create more struggles in one state over another. California may object because of the violation of the priority water right, and could decide to litigate, which would be very detrimental to managing the river."

The options proposed by the Bureau present the urgent need to do something about the Colorado River's depleting flow. There has been an increased need for basin states to implement policies that conserve water for some time, but there has not been much movement in this area, Zagona said.

"Reclamation since last summer has asked the states to agree on a proposed plan among themselves for voluntarily reducing deliveries, but the states have been unable to do so, mainly because California wants to stick to the prior rights principle and the other states think that should be relaxed to spread the these painful reductions among them," Zagona said. "So now Reclamation needs to - and will - end up with a plan for reductions through the SEIS process, but still would prefer that the outcome look like a plan that the the states agree on amongst themselves. It looks like by proposing the two rather extreme policies, Reclamation hopes that it will motivate the states to try to negotiate a mutually agreeable plan that Reclamation can adopt."

It's expected that a policy approved by the Reclamation will be implemented in August. It will likely operate in a way that protects the reservoirs and stops them from dropping to dead pool levels.

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