Purifying Water With Nanotech - IEEE - The Institute

Graphene membranes, the tiniest thing, could be a very big thing. Pure water is a limited quantity in the western US, and especially here in San Diego where it costs $Billions as we have to import all our water. It was only a hundred years ago in December 1913 that engineering on a very big scale brought water to Los Angeles, making possible its rapid growth. It is frustrating when you consider we're sitting next to the Pacific Ocean. RO plants have been proposed, but are very energy intensive and expensive. This problem needs to be solved to avoid the predicted water crisis in the book below. 

The West without Water - B. Lynn Ingram, Frances Malamud-Roam - Hardcover - University of California Press
Book Review: Scientific American

Purifying Water With Nanotech - IEEE - The Institute

Jeffrey C. Grossman, MIT associate professor of power engineering, and his graduate students David Cohen-Tanugi and Shreya Dave are developing a filtration material made of a sheet of nanoporous graphene. The holes in the graphene—a one-atom thick form of carbon—are small enough to block salt ions while letting water molecules through. Smithsonian magazine called this nanoporous form of carbon one of the top five surprising scientific milestones of 2012.
Cohen-Tanugi presented their paper, “Water Desalination Across Nanoporous Graphene,” at the IEEE Conference on Technology for Sustainability, held in August, in Portland, Ore.
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100 Years Ago: Engineering Brings Water to Los Angeles, 1913: Scientific American
Water for a City

“The new Los Angeles Aqueduct is designed to bring 265 million gallons of water daily over a distance of 234 miles from the Sierras to Los Angeles. This new aqueduct was dedicated and opened to use on November 5th, and on our front page of this week's issue we present a view taken at the moment when the gates were opened to start the flow of water down the cascade formed below the exit of the tunnel through the Santa Susana Range, 25 miles northwest of the city of Los Angeles. This cascade fulfills a double function—it was designed partly on esthetic grounds, but also for the purpose of assisting in the purification of the water by aeration.”
LA Aqueduct Centennial | Los Angeles Department of Water and Power
History of the LA Aqueduct