The Japanese industrial and engineering firm, Hitachi Zosen Corp., has designed a desalination system that uses heat from waste incineration.^[1]  Hitachi Zosen developed this desalination system with a view towards promoting its use in the Middle East.   The system desalinates water through reverse osmosis and distillation.  The burned waste enables the production of water, either by turning a turbine to generate electricity for the reverse osmosis process; or, by directly providing heat for a distillation process.  There is an efficient correlation between the amount of waste that is burned and the amount of water produced: one ton of garbage produces roughly 100 tons of water (i.e. 600 kilowatt-hours of electricity).^[2]

The commercial operations of the Carlsbad desalination plant may soon ease mandatory water restrictions for residents of San Diego County.  Last week, the California Water Resources Control Board adopted a new regulation that permits the San Diego region “to receive drought-resiliency benefits” from the desalination plant that would enable the region to reduce its water conservation efforts.^[3]

The San Diego County Water Authority is currently working with California state regulators to ease water-reduction targets by 8 percentage points.^[4]  In June 2015, state regulators ordered the member agencies of the Water Authority to reduce water use by 12 to 36 percent through February 2016 (compared to baseline levels in 2013).  Between June and December, water use in San Diego County reduced by 24 percent (greater than the 20 percent target set by state authorities).^[5]  Since May 2015, the conserved water has been stored in the newly expanded San Vicente Reservoir.^[6] 

The State Board first has to consult with the Water Authority about the Carlsbad plant’s water supply; and it must also assess the result of snow conditions in the Sierra Nevada that are revealed each April (in normal years, snowfall supplies about 70 percent of California’s annual precipitation, and provides ample runoff for California’s reservoirs).^[7]  The existing emergency legislation requires every local water agency to reduce water use by a minimum of 8 percent (compared to 2013 baseline levels); and it is expected that the San Diego region will have to meet higher conservation targets.^[8]

Meanwhile, in Tobruk, Libya, a leak in the main pipeline that supplies water to the coastal city may lead to the shutdown of its only water source.  Fathallah Saleem, Director of the Tobruk Water Desalination Plant, has reported that if the leak in the pipeline is not repaired, they will have to shut down the plant’s operations because they are financially unable to purchase the materials to maintain the line.^[9]  Saleem also reported that three months ago, a water leak affected the same pipeline; the government assured desalination plant officials that they would resolve the problem—but they have not yet made an effort to do so.^[10]