Lake Mead could be dry by 2021

Lake Mead could be dry by 2021
A map of the Colorado River basin. Credit: Scripps Institution of Oceanography, UC San Diego

There is a 50 percent chance Lake Mead, a key source of water for millions of people in the southwestern United States, will be dry by 2021 if climate changes as expected and future water usage is not curtailed, according to a pair of researchers at Scripps Institution of Oceanography, UC San Diego.

Without Lake Mead and neighboring Lake Powell, the Colorado River system has no buffer to sustain the population of the Southwest through an unusually dry year, or worse, a sustained drought. In such an event, water deliveries would become highly unstable and variable, said research marine physicist Tim Barnett and climate scientist David Pierce.

Barnett and Pierce concluded that human demand, natural forces like evaporation, and human-induced climate change are creating a net deficit of nearly 1 million acre-feet of water per year from the Colorado River system that includes Lake Mead and Lake Powell. This amount of water can supply roughly 8 million people. Their analysis of Federal Bureau of Reclamation records of past water demand and calculations of scheduled water allocations and climate conditions indicate that the system could run dry even if mitigation measures now being proposed are implemented.

The paper, “When will Lake Mead go dry?,” has been accepted for publication in the peer-reviewed journal Water Resources Research, published by the American Geophysical Union (AGU).

“We were stunned at the magnitude of the problem and how fast it was coming at us,” said Barnett. “Make no mistake, this water problem is not a scientific abstraction, but rather one that will impact each and every one of us that live in the Southwest.”

“It’s likely to mean real changes to how we live and do business in this region,” Pierce added.

The Lake Mead/Lake Powell system includes the stretch of the Colorado River in northern Arizona. Aqueducts carry the water to Las Vegas, Los Angeles, San Diego, and other communities in the Southwest. Currently the system is only at half capacity because of a recent string of dry years, and the team estimates that the system has already entered an era of deficit.

“When expected changes due to global warming are included as well, currently scheduled depletions are simply not sustainable,” wrote Barnett and Pierce in the paper.

Barnett and Pierce note that a number of other studies in recent years have estimated that climate change will lead to reductions in runoff to the Colorado River system. Those analyses consistently forecast reductions of between 10 and 30 percent over the next 30 to 50 years, which could affect the water supply of between 12 and 36 million people.

The researchers estimated that there is a 10 percent chance that Lake Mead could be dry by 2014. They further predict that there is a 50 percent chance that reservoir levels will drop too low to allow hydroelectric power generation by 2017.

The researchers add that even if water agencies follow their current drought contingency plans, it might not be enough to counter natural forces, especially if the region enters a period of sustained drought and/or human-induced climate changes occur as currently predicted.

Barnett said that the researchers chose to go with conservative estimates of the situation in their analysis, though the water shortage is likely to be more dire in reality. The team based its findings on the premise that climate change effects only started in 2007, though most researchers consider human-caused changes in climate to have likely started decades earlier. They also based their river flow on averages over the past 100 years, even though it has dropped in recent decades. Over the past 500 years the average annual flow is even less.

“Today, we are at or beyond the sustainable limit of the Colorado system. The alternative to reasoned solutions to this coming water crisis is a major societal and economic disruption in the desert southwest; something that will affect each of us living in the region” the report concluded.

Source: University of California - San Diego

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Feb 12, 2008
No one wants to be alarmed by the alarmists but Lake Mead is going down one foot per week on average according to local news and reporting organizations here. Conservation steps are in force and plans are being made but I am not priveledged to be in on that. We need to do something and just talking about it without doing some serious planning is ridiculous. I don't agree with Al Gore in everything nor do I believe everything else I read about global warming but the south west is obviously drying up and that can be proved.

Please ..... read the article! ' 2021?' '.... if climate changes aren't curtailed?'. IF (and I do mean IF) we cause any fraction of the warming, what could we possibly do by 2021 (actually it would have to be implemented yesterday) to turn the situation around? The very wording shows an agenda. Or in the case of Lake Mead is it too many people draining water off downstream?

Feb 13, 2008
It is true that the Colorado River's resources are over-exploited by the booming population of the SW. That's very old news.

However, crediting the questionable theory of AGW as the problem is like the Aztec priesthood blaming Quetzalcoatl for the Spanish invasion.

Climate modelers claim that their models don't do "forecasts" but "scenarios." These models are extremely slack without any verification and validation standards mandatory in industries, such as nuclear power or civil engineer. No decadal climate model has ever been tested in the real world successfully.

Yet, our climate high priests put forth their unquestioned models to government and taxpayers as the basis of long term planning that involves billions, aye, even trillions of dollars in economic reorganization.

Meanwhile, the planet seems to have entered a cooling "scenario" that none of the GMCs "forecast."

Perhaps we should all sit down take a few deep breaths and fund some seriously third party audits into the climate science behind apocalyptic "scenarios."

Feb 13, 2008
Hahahahahahah This is a well deserved punishment. I shall call this a Theory of Lake Mead.. I'm pretty sure someone can dig up a few scientists to say the lowering water is not a problem.

Feb 13, 2008
Report from New Mexico dated 01/28/2002

Quote from 1997 report. "A recent Irrigation Association (IA) breakdown of golf course water use by state showed that the most water was used where the most water issues exist: Florida, California, Texas and Arizona. In Florida, more than 1,000 courses use a total of 137 billion gallons a year. In California, 883 courses use around 90 billion gallons. Texas' 780 courses consume 56 billion gallons and Arizona's 259 courses swallow 28 billion gallons." unquote.


Note the use of Arizona and California. These figures are deemed low considering GC expansion. I do need to add that not all of the use Lake Powell water, but will affect the usage in other consumption areas.

At any rate, blah blah blah. Go Fish!

Feb 14, 2008
FWIW, water content of the snowpack in southwestern Colorado (part of the upper Colorado River Basin)is higher now than the average for an entire winter. And the snowiest months (Feburary and March) are still mostly ahead. Maybe that will help.

Feb 15, 2008
Although I don't know all the details on this issue, I did do conservation work around Lake Mead for a while. From what I understand, the main problem is the rapid growth of Las Vegas - the city is pumping more and more water out of the lake at a rate that the Colorado has no chance of keeping up with. Add to this factors such as global warming and invasive plant species that use far more water than local plants, and Lake Mead will be gone in no time. You can actually see a ring around the lake, 50 or so feet up, where the water level was when the Hoover Dam was completed.

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