Water. Desalination + reuse
Issue link: https://fhpublishing.uberflip.com/i/1056083
ENERGY CONSCIOUS • Plant serves 30 per cent of City of Santa Barbara daily water demand • Desalination considered a vital part of portfolio of water resources • IDE Americas has a five-year operations and maintenance contract The City of Santa Barbara Charles E. Meyer Desalination Plant was originally built during the early 1990s as a response to drought. The plant operated from March to June 1992, and then went into standby mode. The drought of the early 2010s led Santa Barbara City Council to vote unanimously in favour of reactivating the plant, in 2015. The capital cost of the project was $27 million, including a $10 million grant from the California Department of Water Resources. A design, build, and operate contract was awarded to IDE Americas, which has a five-year operations and maintenance contract. The plant was designed with a view to minimising energy use and environmental impacts. Seawater is drawn from the Pacific Ocean through wire screens into an intake pipe half a mile (805 metres) offshore, at a depth of 40 feet (12 metres). The pre-treatment system doses ferric chloride for coagulation and flocculation, and separates particles from the water through media filters. The cleaned-up seawater then goes to the reverse osmosis (RO) system. The RO consists of three lots of 30 pressure vessels, each having eight RO membranes (that's 720 membranes). Each module incorporates three energy recovery devices, reducing the 18 On Site December 2018 Water.desalination+reuse The City of Santa Barbara is set be- tween the Santa Ynez Mountains and the Pacific Ocean. The re-activated Charles E. Meyer Desalina- tion Plant project has proved so popular that residents want to know if supplies from the plant are pumped to their own street specifically. City of Santa Barbara diversifies with desal amount of energy required to run the RO by 40 per cent. The waste brine produced by the RO is pumped to a large mixing chamber at El Estero Wastewater Treatment Plant, a facility located across the street. There it's combined with treated wastewater to reduce its salinity before discharge to the ocean through diffuser pipes. The permeate is treated with ultraviolet light and chlorination for disinfection. Finally, it is remineralised: powdered limestone and carbon dioxide are added to adjust the pH and alkalinity, helping to prevent corrosion of the city's drinking water pipes. The plant produces three million US gallons a day (11,356 m3/d) of drinking water, or about 30 per cent of city residents' demand. The remainder is sourced from reservoirs, groundwater, the State Water Project, recycled water, and through conservation efforts. The City of Santa Barbara Charles E. Meyer Desalination Plant is located between the Pacific Ocean and the city, across the street from El Estero Wastewater Treatment Plant. Brine from the reverse osmosis (RO) modules is mixed with treated wastewater before discharge into the ocean. The plant's modular design consists of three RO units, each operating with three energy recovery devices to reduce energy use.