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Things you didn’t know about water

Fully 97 percent of the Earth’s total water supply is the salt variety found in oceans and seas. Find out other interesting facts related to this precious resource.
Wei Yan/Masterfile
Wei Yan/Masterfile

Comedian W.C. Fields famously rejected it as the medium in which fish conduct their reproductive activities, but he couldn’t escape it entirely.

After all, it comprised more than 60 percent of his body, 70 percent of his brain, 80 percent of his blood and nearly 90 percent of his lungs.

What “it” is, is water.

Every living thing needs water to live — humans, who can go a month without food, die after just a week without their H2O — and every living thing contains it to a significant degree. Water makes up 75 percent of the average chicken and tree, for example, and 80 percent of a pineapple.

To the extent that it exists outside of us, it is very, very old. The same amount of water exists today on Earth as existed 3 billion years ago, and, thanks to the “water cycle,” it’s the same water, moving unendingly from sea to clouds to rain to earth and back again.

Could the raindrops that tomorrow run the mascara of a fashionable New Yorker be the same drops that once bathed the unruly hair of a Neanderthal man? Well, yes.

Water, water, everywhere ...
Water is also ubiquitous and abundant. Consider:

  • About 70 percent of the Earth is covered by water.  
  • The total water supply of the planet is estimated at 326 million cubic miles. (One cubic mile of water equals more than 1 trillion gallons.)
  • If all of the planet's water was poured in the United States, it would cover all the land in an ocean with a depth of 90 miles.
  • An estimated 3,100 cubic miles of water is in the planet's atmosphere at any one time, mostly in the form of vapor.  If it were all dumped in the form of rain, the entire surface of the earth would be covered in one inch of water. (In the “Did you know?” category: Water is the only natural substance that can exist in all three states — liquid, solid and gas.)
  • The continental United States receives anywhere from 3.5 to 4 cubic miles — 12 trillion gallons — of precipitation each day. 

That’s a lot of water to be sure. However, when it comes to the fresh water needed by humans and other creatures to survive, Samuel Taylor Coleridge seems to have got it about right when he wrote, “Water, water, everywhere, but not a drop to drink.”

Fully 97 percent of the Earth’s total water supply is the salt variety found in oceans and seas. As for the fresh 3 percent, most is stored in the 7 million cubic miles found frozen in glaciers and ice caps; another 2 million cubic miles is underground, most within one-half mile of the surface. The most available fresh water supply — in lakes, inland seas and rivers — accounts for only 60,000 cubic miles.

Humankind’s great thirst
Still, this relative lack of freshwater does not prevent the human race, and especially its U.S. denizens, from using water with scant regard for conservation.

Americans use more than 400 billion gallons per day of both surface and ground water, much of it consumed in and around the home. Some facts to consider, courtesy of the Environmental Protection Agency, next time you’re brushing your teeth or listening to a leaky faucet in the middle of the night:

  • The average American uses about 160 gallons of water a day at a cost of 27 cents.
  • Two-thirds of the water used in an average home is used in the bathroom, much of it consumed by the toilet, which requires four to six gallons per flush.
  • The average person uses 2 gallons of water per day to brush his teeth.
  • A 10-minute shower uses about 55 gallons of water.
  • Lawn watering accounts for at least 50 percent of a typical household’s water consumption.
  • Automatic dishwashers require approximately 9 to 12 gallons of water per load of dishes, compared with the 20 gallons required to do the same dishes by hand.
  • If every household in America had a faucet that dripped once each second, 928 million gallons of water a day would leak away.

Industry, too, likes its water, expending 39,000 gallons to manufacture the average domestic automobile and 300 million gallons to provide American newspapers with the newsprint they need for a single day. And the next time you enjoy a Quarter Pounder at McDonald’s, realize that it took about a gallon of water to process your burger.

Though the water supply is static, the demands on it are increasing with population and all the associated human activities. But as long as an 8-ounce glass of water can be refilled 15,000 times for what it costs to buy a six-pack of soda, don’t expect anyone to voluntarily go without it.

Philipp Harper is a freelance writer living in south Georgia.