CalDesal Newsletter 2015 – Issue No.1

The proposed new rules for intakes and mitigation still find subsurface intakes the best available technology but leave the door open for open ocean intakes under certain conditions.  If subsurface intakes are shown to be infeasible, open ocean intakes could be utilized with a passive intake screen (“wedge wire screen”) that  must be sized at 1 millimeter or smaller, the intake velocity must not  exceed one half foot per second, and the screened ocean intake would require mitigation. As for Brine Disposal, mixing brine concentrate with wastewater is still viewed as the best available technology, but diffusers may be used under specified circumstances. Discharges shall not exceed a daily maximum of 2.0 parts per thousand (ppt) above natural background salinity measured no further than 100 meters horizontally from the discharge.

On the first of April, Governor Brown announced that he was going to call on California Urban Water users to cut their water use by 25% statewide from 2013 use in order to meet the challenges of a four-year drought emergency. While the first time ever mandatory water conservation emergency order is getting all of the attention in the press, there is more to the Governor’s Executive Order B-29-15 including streamlining government response for increasing local water supplies, such as water recycling facilities and desalination plants (Section 19). Indeed, the executive order calls for investment in new technologies including renewable energy-powered desalination (Section 17). Plan on seeing just as much press on these two sections in the future