Q&A on the News

Q: While I was in Saudi Arabia, I learned that Riyadh, which is 700 miles from the sea, is totally supported by water desalination facilities. Why can’t Georgia build a plant or plants on the coast and provide an endless source of fresh water for the entire state and possibly north Florida?

—Frank Walker, Marietta

A: Desalination works in certain situations, but is unsuitable or too costly for others, Aris Georgakakos, director of the Georgia Water Resources Institute at Georgia Tech, told Q&A on the News in an email. "Desalination would work well for domestic water supply for communities along the coast," he said. "This is because the amount of water needed and the cost of its transport to the places of demand are fairly low. As the amount of water needed and/or the transport costs increase, desalination becomes increasingly costly." It would be uneconomical to construct plants on the coast to supply Atlanta, he said, because of the cost of moving millions gallons of water a day from the coast to north Georgia. "The actual cost would be in the billions per year," Georgakakos said. He said desalination also produces an "environmentally undesirable effluent." A 2008 AJC article stated that the process takes a large amount of energy, and "the power needed for purification goes up with the salt content of the source water." Georgia's rivers also dump a high amount of sediment into the ocean, which can foul the filtering process, the article stated.