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Are We Running Out of Water?

Photo: Dry river near Darcha in India
A dry river near Darcha in India. Ankit Solanki, Flickr Creative Commons

 

Early in 2001, the Rio Grande River failed to reach the Gulf of Mexico for the first time.

With that nefarious event the Rio Grande joined a growing list of once-mighty rivers that are running dry from overuse:  the Colorado River in the U.S., the Yaqui in Mexico, the Indus in Pakistan, the Ganges in Bangladesh, the Yellow and Tarim in China, and the Murray in Australia, along with many other rivers large and small.

Not surprisingly, fisheries in these once-bountiful rivers have crashed.  After all, fish do need water.

We’ve tapped underground water sources pretty heavily as well.  The water level in the Ogallala Aquifer in the Midwestern U.S. has dropped more than 150 feet in some places, leaving many farmers’ wells bone dry.

As water is sucked out of aquifers, the overlying soil and rock can compact or collapse into the dewatered void, causing tall buildings to teeter in Mexico City, automobiles to tumble into sinkholes in Florida, or swallowing tourists on the fringes of the shriveling Dead Sea in Israel and Jordan.

With so many rivers, lakes and aquifers going dry, we have to ask:  Are we running out of water?

The Big Picture

 The glass-half-full answer is no……. at least not at the planetary level.  Today there is just as much water on the planet as there was when the first signs of life appeared.

Every year, about 110,000 billion cubic meters of water falls on the land surface of our planet as rain or snow.  That annual endowment of water would cover all land to nearly a meter deep if it was spread evenly.

More than half of all of that water evaporates quickly or gets taken up by trees, shrubs, and grass.

More than a third flows out to the coasts, where it helps to maintain the delicate salt- and freshwater balance of estuaries, without which much of our seafood industry would collapse.

Of all the water falling on land, we’re consuming less than 10% to grow our crops, supply our homes, keep our industries running, and generate electricity.

Every bit of the water that falls on land or in the ocean or is used for human endeavors is eventually evaporated back up into the sky as water vapor, replenishing our planet’s never-ending freshwater cycle.  No water is actually ‘lost’ in that global cycle.

So what’s the problem?  Surely we can’t be in trouble if we’re depleting less than 10% of the Earth’s naturally renewable water, and the water cycle keeps bringing that water back year after year?

Here’s the catch:  the water that falls from the sky isn’t evenly distributed around the globe, and our needs for that water aren’t the same everywhere.

So why can’t we just move water from places of abundance to places of shortage?  Why can’t we take the fresh water flowing to the Arctic Circle and redirect it to the parched cities of the American Southwest?

Such plans have been on the drawing boards of big water dreamers for decades.  In truth, the only thing that has stopped these initiatives is the fact that far less costly alternatives usually exist for meeting our water needs in the near term.  We only have to look to the South-North Water Transfer Project in China for a bellwether of what may come.  The Chinese will invest $62 billion to build a pipe-and-canal system to move water over hundreds of kilometers from the Yangtze River to parched cities and farms in the north.  As the New York Times reported last year, “It would be like channeling water from the Mississippi River to meet the drinking needs of Boston, New York and Washington.”

But here’s another catch:  Even if we could move water over great distances in a cost-effective manner, it takes a tremendous amount of energy to do so.  Nearly 20% of all electricity used in California – whose statewide plumbing system is reminiscent of a Rube Goldberg design – is spent moving water around.  The energy required to move water – and its associated carbon emissions — is not inconsequential in the efforts to arrest climate change.  Until we have abundant clean energy sources to power such re-plumbing of the planet’s water sources, we should not be investing in them.

And yet one more important consideration:  We should be careful about ‘robbing Peter to pay Paul.’ As we dry up a river or lake to harvest or export its water, the health of fish populations and natural freshwater ecosystems plummet.  In virtually all of the large rivers that have begun to go dry, fisheries have been decimated, leading to severe hardship for local people that depend upon that food source for their subsistence and livelihoods.  Last year, I published a journal paper with colleagues at The Nature Conservancy that suggested that depletion of a freshwater source by more than 20% will likely have harmful ecological and social consequences.

The conclusion that should be drawn from all of this:  we need to take stock of our local water sources and manage them wisely.  As my water colleagues like to say, that “All politics — and water — are local.”

 

This map portrays the number of months each year in which the depletion of water for human uses is greater than 20% of the naturally-renewable water supply in rivers, lakes and aquifers (based on averages from 1996-2005). More than half of the more than 400 water basins analyzed are experiencing water scarcity during some part of the year. From Hoekstra et al. 2012

Taking Stock of the World’s Local Water Accounts

 Nearly half of all the water that falls on land ends up in a river, lake, or aquifer before being used or flowing out to sea.   We can think of these freshwater sources as individual water accounts.  Some examples: the Colorado River basin, the Great Lakes basin, and the Ogallala Aquifer.

But unlike money accounts, it is untenable to move large volumes of water from account to account.  Therefore, it only makes sense to pay close attention to the balance in our local water accounts.

When managing these water accounts, it is quite helpful to think of them in much the same way as you think about your personal bank account: over the course of the year, you make some deposits and you take out some withdrawals.  If you continuously take out more than you deposit, you’re headed for trouble.

The bankruptcy of our unsustainable water use can be measured in the drying of rivers and the drawing down of aquifers.  In many river basins and aquifers we are taking out more than is deposited by rain or snow.

Until recently, we have not had a decent balance sheet or map to tell us how our water accounts were doing.

The map above is a good first measure of how much water is being depleted from our global water stocks.

This recently published map is a fruit of the labors of an Ethiopian PhD student named Mesfin Mekonnen and his mentor, Arjen Hoekstra at the University of Twente in The Netherlands. (disclosure: I was a small-bit co-author on the paper that included this map). To produce this map, Mekonnen and Hoekstra calculated how much of the water in each freshwater source was being depleted by agriculture, industry, and domestic uses.  They then compared the volume of water being depleted with the amount of water flowing into rivers, lakes, and aquifers each year.  For any month of the year in which the cumulative water depletion exceeds 20% of the water falling from the sky, they flagged as being “moderately water scarce.”  The map shows how many months are determined to be water scarce in each of more than 400 river basins globally.

An important conclusion from this study:  in nearly half of the water basins evaluated, more than 40% of the renewable water supply is already being depleted.

As with any map depicting global conditions, this one surely has its inaccuracies.  Better data are available in many locales, which can reveal a more accurate reading of the status of local rivers, lakes and aquifers.  But with this study, Mekonnen and Hoekstra have finally given us an initial answer to what may be the most pressing question of our time:

How much water is left?

Comments

  1. jay
    florida
    November 21, 6:07 pm

    google about china steeling our water from the great lakes from our aquifers , foot ball field size bags as long and wide 6 or 7 feet tall and as many as 5 or 6 of these containers at the same time dragging them back with a vessel to replenish there aquifers unreal if this is true please quote me if im right or wrong this must stop who authorized this

  2. Mark
    Massachusetts
    July 24, 4:03 pm

    It’s a simple solution if people would stop eating all meats and dairy. 70% of our water supply goes to raising animals for food. Instead of eating the cow to get protein you can eat many delicious veggies and beans and nuts and legumes. The key to tasty food is spicing. Try eating a piece of meat with nothing on it and it tastes bland, a vegan like me won’t eat a salad unless theirs a nice salad dressing on it. The point is is that until people go back to a simple natural way of eating, we will always have this problem and no amount of low flush toilets will solve the problem.

  3. h20
    houstone,tx
    June 24, 12:14 pm

    H20 is unique

  4. Kate
    Kemmerer Wyoming
    April 2, 4:54 pm

    It blows my mind as I watch billions and billions spent on transporting oil and gas in pipelines that crisscross this country but no water lines. Yes I takes power to push it through but if it is set up right it also produces power as it is pushed through. Equaling out the power problem. Why more and more old lake area’s are not dredged and rivers that have filled in with silt dredged, makes a person wonder. We have the knowledge, we have people who need work, apparently we just don’t have someone running the company who will do it.

  5. MeT
    North America, Louisiana
    October 27, 2013, 11:52 am

    We have lots of salt water and freshwater mixing down here, but if they take the melting snow from the Mississippi River before it reaches Louisiana we have more fresh water to spare and share. P.s. I’m under 12! I can even think of better things than government.

  6. siddharth
    india
    October 2, 2013, 4:44 am

    why do lakes now-a-days receives more water from sewage than natural water

  7. Are We Running Out of Water? | Orior
    September 29, 2013, 3:09 am

    [...] Are We Running Out of Water?. [...]

  8. [...] image: UNESCO. Other sources: National Geographic, NASA, New Scientist, New York Times, Places Journal, Water and [...]

  9. [...] [National Geographic, NASA, New Scientist, New York Times, Places Journal, Water and Power] [...]

  10. jonny
    Tennessee
    August 25, 2013, 4:33 pm

    Aquaponics is a good way to grow our food without using much water at all. Reducing mosquito pop and raise fish for eating. We could take that 10 percent and make it way less, while still feeding everyone well.

  11. Shahzeb
    Canada
    August 14, 2013, 5:35 pm

    Hey.. Yes we are running out of water but I have a question;
    Q. Can’t we purify the oceans water and make it clean for drinking?
    Another fact: they say: WW3 is going to be based on water and countries will fight over water. But We can get ourselves water from the ocean .. no?

  12. [...] (See "Are We Running Out of Water?") [...]

  13. [...] Earth’s population grows and global temperatures rise, we are rapidly and unsustainably depleting and polluting our water resources. The rate of groundwater withdrawals is unprecedentedly high [...]

  14. Alice
    Australia
    May 19, 2013, 12:47 am

    This article has been very useful, thanks. The article stated that the problem was that once water has evaporated, it doesn’t rain down again on to the same place it evaporated from. Is there any pattern as to where it precipitates? Could it be possible in the future for us to be able to change where it rains? Thank you!

    • Brian Richter
      May 20, 2013, 8:47 am

      Alice, considerable effort has been expended in trying to perfect the practice of “cloud seeding,” in which a substance — usually silver iodide, dry ice, or salt — is sprayed into the air in an effort to cause condensation of moisture and induce rain. The results have been mixed and inconclusive. One concern is that by inducing rainfall in one place we could be robbing some other place of the rainfall it would have received. All in all, not a practice that I’m betting on!

  15. Chris
    May 9, 2013, 10:29 am

    I don’t see how water is being wasted, it’s not like water is leaving earth. If you wash your car, that water evaporates and eventually becomes rain, which refills lakes & rivers. It all goes back to the earth. When we drink water, we eventually pee it back out.

  16. AL
    Dallas, Texas
    May 2, 2013, 12:31 am

    Study says Colorado River water supply to fall short of demand. Why not reduce demand by reducing water waste in the areas that depend on that water supply? The Water Select® valve reduces water used in the shower by 20% to 70%. It is a one of a kind product that was just released on the market. For more info go to water-select.com

  17. [...] Unbeknownst to many people, this is an age when grand rivers and long-time water sources like the Rio Grande and the Colorado River are running dry, which is pushing companies and state governments to look at other long-term alternatives for [...]

  18. Mark Antonio Trimble
    South Africa
    March 21, 2013, 8:26 am

    In Africa, India, Asia and most South American countries pollution of water through contamination by the Industrial sector who dumps toxic fumes and waste into our rivers, dams, ocean and underground water resources. The mining sector is another culprit in contaminating and depleting our water supply. Less than 5% of human waste that is annually dumped into our rivers and dams are by those villagers and rural communities who have no access to running water and toilet facilities.

  19. Ian Ferry
    Queensland Australia
    January 27, 2013, 5:32 am

    But what about the water re-entering the atmosphere as we burn fossil fuels ? About 1 litre of water for every kg burned if I recall High School science. Not just carbon dioxide is a by product of combustion, but water too. We have more water, not less.

    • Brian Richter
      January 30, 2013, 10:57 am

      Thanks for bringing this to my attention, Ian. I hadn’t realized that we are actually making “new” water when we burn fossil fuels. Apparently this results from the release of hydrogen from the fossil fuel, which combines with oxygen in our atmosphere to form water vapor. But it doesn’t amount to much in a relative sense. With help from Michael Webber at University of Texas and John Matthews at Conservation International, we estimate that the volume of new water created in this manner would amount to no more than 10 billion cubic meters (BCM) per year. By comparison, annual precipitation on land is estimated at 110,000 BCM per year, another 391,000 falls on the ocean, and another 45,000 BCM is moving through the atmosphere. So the new water created by fossil fuel is literally a drop in the bucket, and not much help for the water-scarce places on our planet.

  20. [...] a bit of context.  At the global scale, we are in no danger of running out of water.  We are presently using only about 4% of the water flowing through and into the rivers, lakes and [...]

  21. Mike Reality
    North America
    December 30, 2012, 2:18 pm

    Yes, we are running out of fresh water world-wide, and yes our consumption and emissions habits are a contributing factor to global warming but not to the degree most of the world thinks. To find the TRUTH behind what’s really causing all of this, all one has to do is google image HAARP WORLDWIDE LOCATIONS and exactly what HAARP is really used for (not the reason that the governments give), then pick up your bibles, read Revelation and pray for a easy departure. The Governments of this earth are not your friends!

  22. Alexis
    Canada
    December 8, 2012, 11:27 am

    I think we are running out of water and soon we will have none , Like right now i am doing a project on this particular thing. and how we can reduce our water consumption . this article plays out alot of infromation . And i think this is very helpful ,

  23. Eileen Carrillo
    Memphis, TN
    November 17, 2012, 5:27 pm

    how does the u.s store fresh water for drinking? and how is food stored in case of prolonged attack or a bad growing season?

  24. [...] another interesting article about water. About one-fifth of California’s energy use is to pipe water from one place to [...]

  25. wayne caddigan
    Logy Bay
    September 8, 2012, 10:40 am

    I believe the worlds supply of fresh drinking water is being

    deminished with each passing decade. The question is what

    is being done about it.

  26. [...] face ecological disasters of ever-greater magnitudes. Water depletion and desertification are not going away. The oceans are stressed to the point where scientists are [...]

  27. Sadat Mazhar
    Pakistan
    August 20, 2012, 10:19 am

    The only solution of that probldn is saving water and creating awareness , but the usa have the high litracy rate in the world, ,, but what about develop and devloping countries like, Pakistan ,how can we change the attitude of people about this serious matter , ?? Here 97 % water once people use that dnt utlize agdin ,ie water treatment etc, and no political intrest and we are very dangrous in condition right now so what,s the step tha take us far away this problem??’?

  28. Ian
    UK
    May 7, 2012, 3:26 am

    I so wish that people in the Uk took the issue of water more seriously?????????????????????????????????
    But everyone in my opinion is blind to the fact that it will run out unless drastic measures are taken now FACT 40 years ago Spain took it very very seriously FACT they now have over 900 desalination plants what is going on here because the day will come and as far as i can see its only a matter of time now till the day arrives and it gone !!! and all the government will say Oh lessons will be learned from this but it will be too lat action must be taken now to avert a disaster FACT IT WILL RUN OUT Thankyou Ian

  29. The Gates of Hell… « UKIAH BLOG
    April 27, 2012, 10:25 am

    [...] water, everywhere, but the world’s rivers are failing to make it all the way to the [...]

  30. [...] water, everywhere, but the world’s rivers are failing to make it all the way to the [...]

  31. Elly Rose Layson
    Philippines
    April 15, 2012, 7:17 am

    We should take care our water like what we care in ourselves. Not only the animals can be affected but also us, a human beings. Must be all countries should be having a program on how to manage our water system. When i was walking outside the house, there are lots of water wasted. From different households. They didn’t know what will be the change of all this. When we can move to protect our fresh water? When is it the end!!!But i know…..GOD will help us…

  32. [...] to the WorldWatch Institute, “some 20 percent of the increase in water scarcity in the coming decades will be caused by [...]

  33. The Cost of Affluence
    April 6, 2012, 10:31 am

    [...] Water, water, everywhere, but the world’s rivers are failing to make it all the way to the oceans [...]

  34. [...] Water, water, everywhere, but the world’s rivers are failing to make it all the way to the oceans [...]

  35. karen oborn
    australia
    March 22, 2012, 8:33 pm

    There are already too many people using too much fresh water for non essential things. Fresh water should be for drinking and medical use only, all other uses, agriculture, households, industry etc. should use recylced waste water or non potable sources without damaging natrual ecosystemsy no expections!

  36. Rob Riordan
    Arlington, Virginia
    March 22, 2012, 11:26 am

    Few of us living in areas that are “robbing” other basins for our daily water probably realize that this is so (thinking about places like southern California . . . when I lived there, I was only vaguely aware that my water was being piped in from hundreds of miles away, and that I was part of the reason that the Colorado River ran dry). Wouldn’t it be a great awareness tool to create and publicize a “water dashboard” for each water basin, to give people (and policymakers) in a single view an idea of where their water was coming from, how big the deficit was in their water account, and how sustainable / unsustainable the usage was?

  37. Ann
    Viet Nam
    March 21, 2012, 9:41 pm

    One day, I stood on the bank of Thu Bon river. I heard my father said that he had swum in this river when he was young. But now, he couldn’t do it any more. The river has been killing by people who bring sand from the river to cities. Water level has dropped, more and more sand are appeared. ” Are we running out of water?”

  38. David Ezell
    California, USA
    March 19, 2012, 3:08 pm

    The importance of the article, regardless, is people are waking up. As a species, we are still learning how the planet works. We have a lot of young science, lots of computer models with data/weighting/feedback issues. It is safe to state that there are huge draw downs of fossil water that is not being replaced. Cali water utilities can and will deliver water to new housing developments with the standard of: with current and projected usage for 75 years. Folly.

  39. Brian Richter
    Crozet VA
    March 19, 2012, 10:30 am

    Dear Abebo Watkins,
    I’m anxious to see that PNAS paper suggesting that there is 30% less water on the planet now. Your point about the balance between fresh and salt water in the global water cycle is a good one, although of course in the time frame of interest to modern society the real issue — which I tried to emphasize here — is the fact that we are seriously depleting the volume of water moving through the fresh water part of the global cycle. I used statistics pertaining only to the land portion of the hydrologic cycle quite intentionally — the point of the blog was to say that there is only so much water moving through the land portion of the water cycle at any given time, and that volume of water moving across the terrestrial landscape gathers in local “buckets” of river basins, lake basins, aquifers. If we deplete those buckets too heavily at any given time, we’re setting ourselves up for catastrophes.

  40. abebo watkins
    texas
    March 18, 2012, 5:31 pm

    there are some factual errors here. for instance, the total amount of water has changed over earth’s history — a recent PNAS paper suggests a decline of about 30 percent of the past few billion years (the paper says this amount is constant). also, what is more important than the amount of water in total is the amount of freshwater versus saltwater — this ratio changes quite a bit. for instance, as recently as 18,000 years ago, much of the the mid to high latitudes of north america, europe, and asia were covered in several miles/kilometers of ice and sea levels were hundreds of meters lower. there was much more freshwater then than now, though much of that water was frozen. we are in a relatively warm, dry period. and of course, climate change is altering this balance between fresh and salt water balances. finally, the stats about water falling on the earth’s surface is quite wrong, since the author assumes that this amount is falling on the terrestrial surface of the planet — most of the precip that falls is on the ocean, which occupies most of the surface of the planet.

    the biggest point the author seems to miss is that the water balance is changing as a result of both human use and climate change, and some of these changes are quite rapid and dramatic and more interesting, really, than just a loss of water. in some areas, there is too much water, or water at the wrong time. and in others, shifts in climate and human use are leading to very sudden drops in water.

  41. Colin Megson
    Leeds, West Yorkshire, United Kingdom
    March 18, 2012, 10:22 am

    Any State or region having to invest in power generation and considering coal-fired or nuclear (PWR) installations, will have to site them near a large source of fresh water, to condense the steam from the steam turbines. This waste heat is useless low temperature heat which is just dumped and, in the process, uses up significant quantities of fresh water.

    The powers that be, should be aware of a nuclear technology which uses gas turbines to drive the electricity generators. The ‘waste’ heat from gas turbines is high temperature and capable of producing potable water from desalination plants free-of-charge – you get twice as much bang for your bucks!

    See a couple of postings on this blog: http://lftrsuk.blogspot.co.uk/2012/03/water-water-every-where-nor-any-drop-to.html and http://lftrsuk.blogspot.co.uk/2012/03/more-potable-water-as-important-as-less.html

  42. Keith Malone
    United States
    March 18, 2012, 3:13 am

    The way I read the California Energy Commission report referred to in this article is that involves not just the transport of water, but the cleaning of water, too.

    http://www.energy.ca.gov/2005publications/CEC-700-2005-011/CEC-700-2005-011-SF.PDF

  43. Joan DeSimone
    Avoca Ny
    March 17, 2012, 9:09 pm

    The Natural Gas Industry is wasting over billions of gallons of fresh water daily to use for extracting gas. in The process commonly known as Fracking. There commercials speak of the clean green energy and its a total lie. It pollutes air, water, kills animals , poisons families. Destroys the natural environment. And most importantly is using up this precious natural resource that we cannot live without. Water…………..

  44. sprindleberry
    western australia
    March 17, 2012, 5:20 am

    For the last two years most of the Eastern States in Australia, including Queensland , NSW and SA have been suffering severe flooding, destroying much property and stock. Many people have been drowned in some areas. A new desalination plant is obsolete. So the map is out of date at this moment.

  45. [...] Are We Running Out of Water? [...]

  46. Rob
    Canada
    March 15, 2012, 8:52 pm

    Next time you buy a drink or worse, bottled water, ask yourself where did that water come from? We need to take more responsibility and quit buying water altogether.

  47. [...] Are We Running Out of Water? [...]

  48. Miles Amblish
    North America
    March 14, 2012, 3:35 pm

    A good article which askes an interesting question and provides additional information. However, it leaves the effects of human activity out of the equation. How is that water being used: people are using that water. Its not bad weather, climate change or aliens that’s consuming the water but a growing human populating in numbers larger than the can be sustained by the amount of available water in a region. The amount of available water can be increased through the use of energy (for things like de-salination plants) and technology (for things like water pipelines). When the population in those areas grow far beyond these measures to compensate then difficult decisions will have to be made.