Desalination:

It is possible to remove salt, or anything else, from seawater using distillation or reverse osmosis filtration. Both of these are expensive, with high capital costs, maintenance costs, and energy requirements. The process also produces at least one gallon of wastewater for every gallon of freshwater produced. We are using more than half of the available freshwater now. Thus when the population doubles, we will need to reduce per capita use or find other sources. In some areas, the western US, the middle east, and parts of Africa, demand already exceeds supply. We can make freshwater, but rain is still much cheaper.

• A good overview from the California Ocean Resources Program
  http://resources.ca.gov/ocean/97Agenda/Chap5Desal.html
• Seawater Desalination in California by the California Coastal Commission
  http://www.coastal.ca.gov/desalrpt/dtitle.html
• The Desalination Directory Online by Miriam Balaban
  http://www.desline.com/
• The US Department of the Interior's Desalination and Water Purification R & D program
  http://www.usbr.gov/water/desal.html
• The Middle East Desalination Research Center
  http://www.medrc.org.om/

Anthony G Benoit  abenoit@trcc.commnet.edu
(860) 885-2386

Revised