캘리포니아 칼슨의 도시 용수 지구(West Basin)는 최근 재생 시설의 재생수의 총량이 1천500백억 gallons를 달성했다.

지금까지 주에 극심한 가뭄이 일어났을 때, 이 물을 일년 동안 대략 370만 사람들에게 제공했다.

West Basin은 1980년 후반~1990년 초반 가뭄 이후에 재생 수 사업을 시작했다.

West Basin이사회는 환경 보호 노력과 더불어 재생수를 다양하게 제공하는 프로그램을 시작했다. 

The West Basin Municipal Water District (West Basin) of Carson, Calif., recently reached 150 billion gallons of total recycled water at its Edward C. Little Water Recycling Facility located in the city of El Segundo -- a new milestone at a time when the state faces one of the worst droughts to date. This amount of water would serve approximately 3.7 million people for one year. 

West Basin began recycling water following the droughts of the late 1980s and early 1990s. At that time, the West Basin Board of Directors embarked on a program to diversify its water supplies by adding recycled water and conservation efforts. In 2007, the Board renamed the West Basin Water Recycling Facility to the Edward C. Little Water Recycling Facility in honor of Director Little's five-term commitment to West Basin and his leadership that resulted in the water recycling facility that now bears his name.

"This water recycling facility is unique; in fact, it is the only one in the world that makes five types of usable water out of wastewater," said Donald L. Dear, West Basin Board Vice President. "One of the five purified waters is injected along the west coast basin to form an underground wall of water that protects local groundwater from seawater intrusion. West Basin's protection of the seawater barrier has the additional benefit of bringing down the salinity of the groundwater by adding ultra-pure, near distilled quality water."

The five types of 'designer' waters the plant produces are: irrigation water (tertiary disinfected); cooling tower water (nitrified); low-pressure boiler feedwater (single pass reverse osmosis); high-pressure boiler feedwater (double pass reverse osmosis); and indirect drinking water (microfiltration, reverse osmosis and ultraviolet light with hydrogen peroxide). The indirect drinking water is highly pure -- minerals are added back to the water before it can be used. West Basin's recycled waters are developed to meet specific customer needs.

Customers of West Basin's recycled water include Chevron, ExxonMobil and Tesoro refineries, Goodyear Airship Station, StubHub Center, Toyota and Honda corporate headquarters, city parks, golf courses, and large landscapes. Approximately 50 percent of El Segundo's water use is recycled water.

The Edward C. Little Water Recycling Facility was recently expanded and increased 

its operational capacity from 30 to approximately 45 million gallons of recycled water per day. This means that 45 million gallons of wastewater is used and not sent to the ocean each day. By producing usable water locally, West Basin has reduced its carbon footprint by saving one billion kilowatt hours of electricity when compared to imported water from Northern California. In addition to water recycling production, the plant's solar-power installation provides 10 percent of the plant's power.

[출처 = Waterworld / 2014년 4월 2일]