LAS VEGAS (KSNV & MyNews3) -- Picture Lake Mead 31 years ago.
Heavy snows on the western slope of the Rocky Mountains in Colorado filled the lake to overflowing. Two feet of water rushed over the Hoover Dam spillway into Black Canyon.
Now picture Lake Mead today – a difference of about 150 feet of water. A white bathtub ring dominates the approximately 820 miles of shoreline.
More than a decade of drought in the tributaries of the Colorado River has greatly diminished the water supply in the lake.
Pat Mulroy, retiring general manager of the Southern Nevada Water Authority, says you can expect the lake to continue to shrink, which scares her because the Las Vegas Valley gets 90 percent of its water from the lake.
If and when the lake drops another 33 feet, which could happen early next spring, the federal government will do something it’s never done before – declare a shortage on the Colorado River. Southern Nevada and Southern California would be forced to live with less water.
If the lake drops another 50 feet beyond that, the valley would face even greater challenges.
In Clark County, the Southern Nevada Water Authority and municipal water agencies launched a plan to pay residents to remove their lawns. It was called “Cash for Grass.”
“My staff pounded me,” Mulroy says. “Why? It was catchy. It worked. They didn’t like it.”
The program worked so well that it became a model for other cities. As the metropolitan Las Vegas area grew, water consumption actually dropped.
But Mulroy says conservation is not enough.
To keep the water flowing, the water authority is building a three-mile tunnel under Lake Mead, heading for one of the deepest parts of the lake.
Mulroy says if the lake drops to an elevation of 1,050 feet above sea level, the upper intake quits drawing water.
“They are accepting there’s a large probability that the lake will drop below 1,050.” Mulroy says. “When that happens, we lose 40 percent of our capacity. That’s very risky.”
Intake 2 runs dry at a level of 1,000 feet above sea level. Intake 3 will be on line by next summer, if all goes as planned. It will draw water all the way down to a level of 860 feet.
So it’s a race against time to complete the third intake.
As another major initiative to keep the valley from going dry, the water authority is seeking new sources of water.
The agency could draw about 25 percent of what is taken now from Lake Mead from underground water aquifers in Lincoln and White Pine counties. The water would be pumped to Las Vegas through a 300-mile pipeline.
But this $3-5 billon project is far from a done deal. Ranchers, environmentalists, elected officials and others have voiced major opposition.
The District Court for White Pine County ruled in December that major portions of the state engineer’s order granting the rural water rights to the water authority were in error.
The authority has appealed that ruling to the Nevada Supreme Court.
If the water importation plan is not ultimately approved and built, it means residents of the Las Vegas Valley will have to find other sources.
As long as it snows enough in the Rockies, water will flow down the Colorado. But it will ebb and flow with the whims of nature. And Southern Nevadans will ebb and flow with it.
“I see a day where we leave water in (Lake) Powell and Mead just to prop it up to get to the next wet year,” Mulroy says. “We had a wet year in 2011. Did it save the river? No. It was followed in 2012 by one of the driest years we’ve experienced in a long time. So, it’s a very dicey proposition.”