Fresh Water from the Sea

Global Challenges/Chemistry Solutions

Water Desalination: Freshwater from the Sea

  Did You Know?

  • Ocean water contains about 35,000 parts per million of salt. Fresh water contains less than 1,000 parts per million.
  • The first scientific paper on desalting was published by Arab chemists in the eighth century.
  • Desalination/distillation is one of mankind's earliest forms of water treatment. In ancient times, many civilizations used this process on their ships to convert sea water into drinking water.
  • Today, desalination plants are used to convert sea water to drinking water on ships and in many arid regions of the world, and to treat water in other areas that is fouled by natural and unnatural contaminants.
  • The largest inland desalination plant in the world, the El Paso-Fort Bliss desalination plant, has a design capacity of approximately 27.5 MGD (30,800 acre-feet).
  • The average cost to produce 1 acre-foot of desalinated water from seawater ranges from approximately $800 to about $1,400.
  • The size of each reverse osmosis membrane pore used in the desalination process is about 1/100,000th the size of one human hair.
“Water, water, everywhere, nor any drop to drink.” So lamented Samuel Taylor Coleridge’s ancient mariner 210 years ago. Today’s scientific advances in water desalination promise to edit that script into “and every drop to drink,” dramatically increasing our ability to transform sea water into fresh water and quench the thirst of 1.2 billion people facing shortages of water.
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Chemical Abstracts Service (CAS®)

SciFinder®, a research tool produced by CAS (a division of the American Chemical Society), found 391 references in the CAS databases on the precise concept of "water desalination" that have been published so far this year. Among these references were 187 patents and 24 review articles. Included in the review articles was the already widely cited paper entitled "Science and technology for water purification in the coming decades". This article was co-authored by Dr. Mark Shannon and Dr. Menachem Elimelech, both of whom are featured in the podcast.

The CAS databases cover references from more than 10,000 major scientific journals and 57 patent authorities worldwide.

In the News


  • Baker M.N., Taras M.J., 1981, The quest for pure water – The history of the twentieth century, volume I and II, Denver: AWWA
  • Crittenden J.C., Rhodes Trussell R., Hand D.W., Howe K.J., Tchobanoglous G., 2005, Water treatment: Principles and design, 2nd edition, John Wiley & Sons, Inc.
  • Diodorus Siculus, 1939, Library of history, volume III, Loeb Classical Library, Harvard University Press, Cambridge, UK
  • EPA, 2000, The history of drinking water treatment, Environmental Protection Agency, Office of Water (4606), Fact Sheet EPA-816-F-00-006, United States
  • K.S. Speigler, Y.M. El-Sayed, 1994, A Desalination Primer Balaban Publishers
  • Outwater A., 1996, Water: A natural history, Basic Books, New York, USA
  • Water Science and Technology Board (WSTB), 2008, Desalination: A National Perspective, the National Academies Press

Sources for this podcast

Other Resources

The waterCAMPWS
The Center of Advanced Materials for the Purification of Water with Systems

Dow Water Solutions
The largest desalination plant in the Southern Hemisphere

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