Las Vegas Water Supply

[chicopee]

Last April (03) I was in Las Vegas and it was brought to my attention of a potential water supply shortage. Lake Mead was in April 80 feet lower than its normal water line (presumably spillway elevation) and that the water line is still dropping today. At the current rate of water consumption what is the predicted crisis date when water curtailment is strictly enforced? When that date arrives will there be enought head to produce hydro-electric power for that city? Will that city remain a real estate boom or will there be a crash? Does any have any thought on this subject?

 

[IRstuff]

The last few years have been mostly drought years, though

TTFN

 

[Focht3]

As I understand things, the water from Lake Mead mostly goes to southern California. As I recall, Las Vegas gets very little, if any, of their water from that source. That tidbit of information stuck with me because it seemed silly, given the proximity of Las Vegas to Lake Mead. It has to do with arrangements made before Las Vegas became the entertainment destination that it is today -

Now, don't ask me where Las Vegas gets its water...



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[JedClampett]

Actually, you've hit on a subject I know a little about. The Las Vegas Valley has two large water treatment plants that use Lake Mead water. One is the Alfred Merritt Smith WTP that can produce about 600 million gallons of water a day and the other is the River Mountain WTP plant that can treat 150 milion gallons of water a day. See

http://www.snwa.com/html/index.html

for information.
When you go to the SNWA website, you'll see that the drought is a huge concern. The restrictions are not too severe yet (watering schedules, etc.) but I'm sure they will get more restrictive if things continue.

 

[4tuna]

Las Vegas is in a drought year...about 8.2 million acre feet of water will flow into Lake Mead this year, while 9.5 million acre feet will be released to meet water demands downstream. Much of this water will go to California. Under an agreement with six other Western states, California is entitled to draw 4.4 million acre feet of water, but has typically used about 5.2 million acre feet of water.

The Imperial Irrigation District in Southern CA, the nation's largest irrigation district, receives more than 3 million acre feet of Colorado water each year -- or roughly 70 percent of California's total river allotment.

California is currently under federal mandate from the U.S. Department of the Interior (DOI) to reduce it's dependance on Colorado river water to allocated levels within the next few years. California's "4.4 Plan" is an ongoing interagency effort to reduce California's use of Colorado River water to the mandated 4.4 million acre-feet per year. It includes water conservation in the Imperial Valley, with transferrence of conserved water to San Diego.

So to answer your question, the reduced use of water by California in the immediate future, combined with return to normal precipitation, should relieve the current water supply shortage in Las Vegas in the near term. This WILL happen -- in response to drought conditions this year, the DOI decided in July to cut water allocation to the Imperial Valley by 400,000 acre feet.

The REAL question is this: How will California make up for the loss of almost a million acre-feet of water, which is about half the residential supply for Southern California?

Answer: ???????

Current proposals include increasing the height of the Shasta Dam (and the size of massive Shasta Lake)in Northern California to provide additional storage capacity.

 

[IRstuff]

Wasn't there recently some news about some shuffling of water deliveries related to the Imperial Valley, which was supposed to relieve the demand on Colorado River water?

TTFN

 

[cvg]

Imperial Irr. District, along with several other major water districts in Southern California, agreed last week to a 75 year plan to reduce that dependance on the river. However, there are some concerns that water quality in the Salton Sea may suffer because of the reduction in flow.

As far as making up the difference, maybe the ag users will actually have to begin conserving water! Up to now, they have not had much pressure - the cost was low and availibility was good, why conserve? Most will say that you need to reduce development, however, most urban development uses less water than agriculture.

How about switching to more low water use crops? They are growing rice and cotton which are water hogs. Maybe genetically engineered crops can be produced to use less water.

 

[jheidt2543]

This has really been a mix of ideas! I'm not picking on cvg, but the farmers are using the water to produce FOOD. If, they switch to other crops, then the food chain changes. If they continue to produce the same food crops, but pay more for the water, then the cost of food goes up. These topics are a LOT more complex than the simple enviormental move proponets are willing to admit (again this is not a jab at you cvg).

There was a PBS show on last night, Tuesday, 10/7/03, that discussed this drought topic from an interesting perspective -- tree rings. Someone studied the rainy and drought years by using the width of tree rings and of course there is a natural cycle to these droughts. But, as the population artifically increases in the arid areas, the demand for water is increased so even if the water cycle returns to a wet one, there is bound to be less water.

It is all trade offs and someone has to give up something sometime. Without good science, economics and ENGINEERING the public just keeps talking about it without finding a balanced solution. That's my nickel (prices keep going up too <G>)

 

[cvg]

I would suggest that more appropriate crops be grown in what is basically a desert. And they (the farmers) really won't have any choice, because the water faucet will be shut off.

As far as population increases in arid regions, that might possibly reduce the water usage. Agriculture (even with more drought tolerant crops) still uses more water per acre of development than residential, commercial or most industrial land uses. So, in the short term, increases in urban development can balance the decreases in agricultural use. I say decreases, because many of these agricultural water users will be persuaded to sell their water rights to the domestic water districts for use in the potable water system and this results in a corresponding decrease in irrigated acreage.

One method being used quite extensively in my area to increase the supply of water is reuse. Treated wastewater can be used for agricultural and turf irrigation and for groundwater exchange.

 

[Focht3]

We all use recycled water; it's just recycled in different ways.


Reduced consumption, reduced irrigation, etc. will all help. But as populations grow, so goes both water and food demands...

<[blue]Focht3[/blue] ducks behind his desk as he types...>

Technology may one day save our collective posteriors, that is, until the new technology begins to create new problems. To me, the biggest paradigm shift will come when/if someone figures out how to create room temperature superconductors. That technology has the potential to make desalination plants very practical, even commonplace. It will be disruptive, but will also have many beneficial side benefits. I hope to see it in my lifetime -



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[jheidt2543]

Focht3, come out from under your desk! You have hit the nail on the head! Technology has already saved our collective posteriors and will continue to do so in the future. In fact, it is our only hope.

Just look at the average human life span since 1900 when it was under 50 and now it is around 75 (in developed countries). Look at the third world to see what life would be like without technology - disease, famine, gruling manual labor.

No matter how much we conserve of anything, it won't be enough, populations and standards of living are rising too fast. Only the continuing increase in the developement and use of technology will help us. The sad part is we are not transfering it quickly enough to the third world countries.

Samuel Florman makes the case much stronger than I do. His books should be required reading in every engineering school, IMHO.

 

[Focht3]

[blue]jheidt2543[/blue]:

Okay, okay - I'm back in my chair. Wireless keyboards are great, but reading my dual monitors in a hand mirror was a real pain!


You're right, of course - a lot has changed in less that 100+ years. My great-grandmother was born in 1875, died in 1976. She didn't take a ride in a &quot;horseless carriage&quot; until she was 40, and never learned to drive. Born in a sod house in Missouri, travelled to Texas in a covered wagon, and lived to see Neil Armstrong walk on the moon - via TV broadcast. What a change!

And the pace of change is increasing...

Hope I live to be 101! Yeah, baby!



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[4tuna]

Oh no! Technology will save us??!??!!??

Take a lesson from biology. For all species that for one reason or another find themselves in an environment without predators, the cycle of life is the same: they expand exponentially until they reach the point where the available resources can no longer sustain them, then the population crashes catastrophically. Humans are no different.

Technology has not slowed this process for us, it has accelerated it. Technology allows us to use 30 times as much energy and natural resources per capita as those in undeveloped countries. Longer lifespans mean greater population and demand on resources. For the majority of our natural resources, we don't have enough to make it the next 30 years given current consumption trends. As underdeveloped countries advance, the picture gets even bleaker.

In terms of water, conservation only goes so far. Desalinization will help, but there are bigger issues: if you desalinize contaminated salt water you end up with contaminated fresh water. How will we get rid of the PCBs and methyl mercury?

The root of the problem is exponential expansion of our population. Until people no longer find it fashionable to have large families, our situation will continue to get worse. Future wars wont be fought over oil, religion, or politics. They will be over fresh water. These wars are already fought in the courts. It's only a matter of time before the US will need Canada's vast freshwater resources. If Canada doesn't give it up willingly, well.....what do you think George Bush III or IV will do?

In Summary: THE END IS COMING! THE END IS COMING!

 

[jheidt2543]

4tuna,

Humans are different than Springtails (Snow Fleas). Snow fleas are a perfect example of the population explosion problem. However, humans have intelligence (at least some of the time) and can correct past or future percieved mistakes. Just recalling the book, Population Explosion should be proof enough. If I'm not mistaken, that book predicted our demise by now. As the standard of living in a country goes up, its population growth goes down.

The thought that we should use less technology would doom all of humankind to poverty, famine and disease. To revert to the level of the stoneage and live in the bush would not solve anything, we would only relive the missery we have escaped.

It was technology that cleaned up Lake Erie, which was said to be dead and never to be able to support fish again. It was technology that purified our water, produces our food, developes our medicines, muliplies our workforce.

The sky is not falling, I'll admit to some low clouds now and then, but it is not falling. Technology is society's only hope. The major problem is that technology is not transfered quickly enough throughout all of society. Yes, there are problems to resolve, but it is our technological abilities that will solve them.

 

[4tuna]

jheidt2543,

I agree that we are different from snow fleas; my post was only half-serious, especially in regard to the end being near. I am neither a Luddite nor environmental zealot, and I certainly recognize and respect the importance of technology in our society. However,I pose the following arguments for your consideration:

The position that technology alone can solve any problem we create is erroneous. In order for technology to &quot;save&quot; us, it needs to be accompanied by global realization of the impacts our day to day actions have on our resources, environment, and long-term viability as a species, before we reach a point of no return. Lake Erie is an isolated example (and yes, there are more), but there many are larger scale, more complex global problems that are not so easily fixed. Where will we put our radioactive waste? How will we reestablish balance in the marine food chain once killer whales become extinct due to PCB contamination? How will we produce food in the midwest when the Ogalla aquifer is completely dry?Show me the technology!

Your observation that humans have intelligence is offset by our strong tendancy and desire for self advancement and personal conveinience, regardless of the impact on the overall population (present or future). For example, even though we know it burns lots of nonrenewable energy and creates air pollution when we drive our big SUV to work, we do it rather than take the train becasue it's more convienient or pleasureable. Not intelligent.

Consider as an analogy the case of lilly pads in a pond. Lilly pads, like population, grow exponentially. It starts as one pad in a pond. A day later there are two, then four, etc. Pretty soon the pond is half full, but if you look at the pond it looks like there is a lot of open water. In reality, you are on the verge of crisis, because the next day the pond will be full. Such is the nature of exponential growth.

In terms of population, our pond is half-full, and soon we will be overwhelmed, but everyone looks around and only sees the open water. Do you think technology will be enough to sustain 15 billion people on this planet? Think hard, because you will have the chance to find out in your lifetime.