The fight for water: Can the mighty Mississippi save the West?

Related list: Dam locations that comprise the Colorado River Basin area

Read more: Lake Powell Pipeline: Albatross or golden goose?

Editor's note: This is the second in a three-part series on the impacts of the West's shrinking water supply and the costly battle to find solutions. Read the first part: The fight for water: Here's why the West's oldest battle could hit you at the tap

SALT LAKE CITY — Towing icebergs to California, diverting Mississippi River water to the Colorado Front Range or building massive plants to desalinize water from the Sea of Cortez are among the options to counter future water shortages in the two basins of the Colorado River.

Other considerations include tearing down all the dams along the system to force groundwater recharge, prohibit new golf courses and place bans on man-made lakes, water parks or swimming pools for single-family homes.

The U.S. Bureau of Reclamation is nearing the final stages of a study that for the first time in more than 40 years is charting projected supply and demand "imbalances" of Colorado River water — which was over-allocated some 90 years ago through a water-sharing agreement among Utah, six other Western states and Mexico. A draft of the study is slated to be released next month, with a final report scheduled for July.

An early analysis by the federal agency predicts that large-scale deficits of water in the river system — greater than 3.5 million acre-feet  — are likely over the next 50 years. It translates into an inability to meet the needs of millions of households, businesses or agricultural operations unless solutions can be found to cut use or increase supply.

The grim scenario is especially plausible given the volatile impacts of climate change, leading the agency for the first time to incorporate how weather changes will play out in specific impacts to the seven states that depend on the river.

"This is a pretty careful scrub of how water demands will unfold over the next couple of decades," said Dave Trueman, the bureau's division chief over resource management.

"The water supply will be different, dramatically different," he said.

Searching for a good idea

As part of its study launched more than two years ago, the bureau solicited public proposals on ways to boost the availability of water, such as building new pipelines from other water sources, increasing conservation efforts, undergoing a massive overhaul of government regulations for the river or seeking prohibitions on large-scale diversions.

The bureau received more than 140 ideas, with some that are drastic, prohibitively expensive, operationally impossible or downright implausible, such as wrapping icebergs in plastic and towing them to California to be melted and used by the West Coasters.

Pat Mulroy, general manager of the Southern Nevada Water Authority in Las Vegas, doesn't laugh at the proposals.

"I don't think any solution, opportunity, should be rejected out of hand right now," she said. "I think this is not a time to put up barriers and say, 'No, this is off the table.' Everything is on the table."

Mulroy knows what it is like to steer a booming desert metropolis through more than a decade of relentless drought that she said was inconceivable in the early 1990s.

"There was a zero probability of drought of this magnitude," Mulroy said. "And climate change was something no one was talking about."