Jeffrey Graham, marine biologist, Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography at UC San Diego
Scripps Institution of Oceanography marine biologist Jeffrey Graham has helped launch what could be a new era in solving California's recurring water shortages. Working with Scripps coastal engineer Scott Jenkins, Graham served as a consultant to Poseidon Resources, a private developer that in August cleared the final hurdle to build the largest seawater desalination plant in the United States.
Graham helped solve one of the dilemmas for commercial desalination plants -- how to deal with the extremely salty wastewater the process produces. For every gallon of freshwater produced, a gallon of wastewater, with roughly twice the concentration of salt as normal seawater, is produced. Dumping it back into the ocean can harm sea life.
Graham's research established maximum levels of salinity for the water returned to the ocean and found that if the wastewater stays within those limits, marine life will not be harmed.
With 20 desalination projects pending in California, his contribution to eco-friendly plant operation could set the stage for expanding California's scarce water resources.
"Ultimately, when permits are drafted for desal plants, there will be clauses that include the boundaries we have established for this company," Graham says. "This is how UC scientists are serving the needs of California. All the environmental problems with the discharge side go away if they use our calculations."
The Poseidon project, located at the Encina Power Plant in Carlsbad, will produce 50 million gallons of freshwater a day, enough to serve 300,000 people. To produce the water, the desalination plant will use reverse osmosis, a process UCLA researcher Sidney Loeb developed in the 1960s. Part of the water the power plant already uses for cooling will go through the reverse osmosis filtering to produce drinking water. The rest of the power plant's water will be used to dilute the salty wastewater, so it can be safely discharged back into the ocean.
Robert Warner, chair, Department of Ecology, Evolution and Marine Biology, UC Santa Barbara
Richard Seymour, head of the Ocean Engineering Research Group, Scripps Institution of Oceanography at UC San Diego
Harmful algal blooms threaten marine life
Mary Wilcox Silver, professor, Ocean Sciences Department, UC Santa Cruz; adjunct scientist, Monterey Bay Aquarium Research Institute