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Published online 19 March 2008 | Nature | doi:10.1038/news.2008.678
News: Briefing
Enough water to go around?
Nature checks out the state of usable water on our planet.
How much water is there on the planet?
If our planet were perfectly flat and its water covered all the surface, it would create a layer 2.
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The numbers in the MORE WATER FACTS appear to be wrong. 2500 tons per year per person in america means 6,8 tons per day, which are 6800 liters per day. The number for China still comes to 1900 liters per day. However, these source [1,2] claim that europeans consumption of water vary in the range from 100 to 200 liters per day and americans are at 300 liters per day. These numbers fit to common sense experience. Even when including industrial use, the numbers do not reach the magnitude mentioned in the article. So, what is included in these numbers? As much as I understand it, the higher number are the result of including the water necessary to grow food. However, there is a wide variation, whether this water is simply rain or has to be delivered by irrigation. I find that without this information the numbers are barely useful. [1] http://www.rwe.com/generator.aspx/online-special-wasser/wasser-wissen/daten-und-fakten/wasserdargebot/language=de/id=312260/wasserdargebot.html [2] http://www.destatis.de/jetspeed/portal/cms/Sites/destatis/Internet/DE/Grafiken/Umwelt/Diagramme/Wasser.psml
Perhaps the above commetor has failed to take into account the various ways in which the average citizen, who is uneducated in the current water situation, wastes water on a daily basis. For example, small personal things like leaving the faucet running while brushing your teeth/shaving, taking long showers, leaving the hose running while washing a car. Or, worse, the way businesses waste water on a daily basis and a larger scale. For example, I have worked in the restaurant business, and witnessed running faucets over frozen food to thaw, or into pots/pans, both just overflowing into the drain. Also, many leaking hoses/connections contribute to the gallons wasted on a daily basis. This is just a couple of isolated examples in one type of business among scores of businesses who waste water on a daily basis. These abominable & blatent wastes will also need to be addressed in the coming years. So, maybe before adding comments that discredit an article concerning a topic that is already not being taken seriously by to many, one should take into account the unknowns such as these untrackable yet significant wastes.
Scott's points are well taken. Talking about businesses, if every business were to conduct a water audit of all the processes that use and waste water, it would add up significantly. This may be mandated in the near future. If you take the practices of individuals who don't practice limits, whether in business or in their domestic lives, again it will add up greatly and show that the majority of Americans still don't practice conservation methods. It just may come down to imposing quotas by our municipal water departments, especially in drought-prone areas. The aquifers out west are drying up, global warming is on the rise. What have we learned from our native Americans. Everyone should watch the movie, Koyanaskatsi - Life out of Balance.
I agree whole-heartedly that potable water supplies will continue to become a more serious problem. But I also believe we take excess in our 'requirements' for granted. I have traveled for several summer months, with daytime temperatures well over 100 F, along the Sea of Cortez with access to only the fresh water carried in my sea kayak, which could only be replenished at local wells every few weeks. My brother and I were fine with less than two liters per day, though of course we used it only for drinking and sea water for everything else. My point is that I suspect in all aspects of water consumption there could be vast reductions of what is deemed necessary.