Las Vegas Sun

March 6, 2015

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Rain will lift Lake Mead water levels, but only slightly

During heavy rainfall it's tempting to believe that the Las Vegas Valley's water woes have ended, that the drought is over and the multi-billion-dollar pipeline project to solve our water shortage can be halted.

Unfortunately, that's not the case.

No doubt rain is better than no rain, but Las Vegas would need a torrent of Biblical proportions to bring Lake Mead back to where it was before the drought, now in its 11th year.

As of 11 a.m. today, the Southern Nevada Water Authority estimated that about 1,400 acre-feet of rainwater had streamed into Lake Mead, a staggering 450 million gallons.

So what kind of dent will it make in Lake Mead's water level, which has fallen about 130 feet? It will raise the lake 2/10s of an inch, according to Water Authority spokesman J.C. Davis.

To raise Lake Mead the full 130 feet would take 3.5 trillion gallons of water. Forty days and 40 nights of this rain, or maybe more.

There is, however, cause for some optimism.

About 85 percent of the Colorado River flow originates with the snowpack on the western slopes of the Rocky Mountain range, and this is shaping up to be a good winter for snowpack. For much of the drought, that snowpack has been far below normal — 25 percent of normal in 2002, 52 percent in 2003 and 88 percent in 2009. And when it has been above normal, it hasn't been by much — 109 percent in 1999, 105 percent in 2005 and 103 percent in 2008.

The latest reports show the western-slope snowpack at 145 percent, Davis said.

"It's a little too early to celebrate," he said, adding that it will change over the course of the winter. "But it's a very good start."

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  1. Something that does help is that So. Cal. got a great deal of rain.

    When ever So.Cal. gets a lot of rain they cut back on the amount of water they take daily from Lake Mead. That will help raise the lake more then the rain we receive here in the Valley.

    During the last big storms in So. Cal. the lake gained a few feet from the cut back orders. Hopefully it will happen again.

  2. Not true, Vegaslee... AZ and CA take all the water from Lake Mead that they are entitled to whether they need it or not. If they don't then their annual share gets slashed and they don't want that to happen.

    What we need is another regional conference on water to determine what the actual expectations for water in the Southwest is. Then we need to re-allocate the water that gets passed around at a much lower level so that growth will be halted in the SW.

    And most of all we need to find new sources of water.

  3. Yeah The Sierra Club are nutcases and very idiotic. They would rather save trees than people's lives. The Green and Clean Energy movement was achieved by everybody EXCEPT those bastards!

  4. When push comes to shove, the desalination plants will get built at a reasonable price regardless what the douchbag Sierra Club does to try to stop it.

  5. you think 2/10 of an inch is unrealistic? Obviously you don't know how big Lake Mead actually is.

  6. OK, I see a lot of discussion of "How could the water level only go up 2/10 of an inch if it rained more than that over the lake?"

    The key here is that people are making incorrect assumptions when they say "over the lake".

    If it had rained more than an inch over the ENTIRE surface of the lake then the water level would have gone up more than an inch.

    Lake Mead is over 112 MILES long. The problem is that the rain only fell over part of the lake.

    So to answer the comparison of it raining an inch over a cup, a bucket, and a pool and all three having an inch of water in parallel this it would be to do that same experiment, but cover the pool most of the way so that only part of the pool in exposed (say 10%)...if you do that you'll find that the bucket and cup have an inch of water and the pool has 1/10 of an inch.

  7. dave202,

    California and AZ water share was set back in the 40's and has never been changed no matter how much or little they take.

    Last time So. Cal. got a lot of rain they cut their daily water orders for over two weeks and the lake came up a few feet. Looks like it is going to happen again.

  8. vegasjjtruth says "What about the runoff from the surrounding area previous commentator?"

    Even with that the amount of water that actually entered lake Mead was only enough for 2/10 of an inch. The total area of the rain over the lake and the area that ran off to the lake still pales in comparison to the size of the lake. Do a little research for yourself please.

    "Do you work for SNWA because your good at spinning the numbers in favor of making things look bad."

    No, I just apparently know a lot more simple physics than you do.

    "My question to you is how did the lake fill up in 17 years if 6 days of rain fills it 2/10 of an inch it would take30 days for an inch 360 days for a foot and 14,400 days to replenish the 130 feet its down!"

    Wow, this one REALLY shows that you don't have even the slightest clue. Rain here in Nevada had nothing significant to do with the lake filling originally...that would have been the water flow of the Colorado River.

    "What I am saying is the numbers are fudged..."

    No, what you're saying is that you have no clue what you are talking about.

    "I want answers!"

    Then go to school and LEARN something. Clueless and ignorant is no way to go through your life.