↑ Reverse osmosis membranes at the Orange County Water District’s Groundwater Replenishment System, the world’s largest indirect potable reuse system.
The National Rise of Reuse BY ALLEN BEST
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rought was pinching the North Texas city of Wichita Falls badly enough that by May 2014 it needed 40 inches of precipitation to catch up. Soon after, a direct potable reuse system began sending treated wastewater through an additional five-stage treatment process approved by the Texas Commission on Environmental Quality. The water was then blended with treated water from two fast-declining reservoirs for delivery to kitchen faucets
Courtesy Orange County Water District
and shower stalls in the city of 104,000 people. T-shirt vendors had fun: “Wee Recycle,” said the lettering on one. City and state officials heard no complaints, although sales of bottled water at Walmart stores increased 9 percent before rains returned. As originally planned, Wichita Falls then modified the direct potable system after 11 months of operation with an environmental buffer, creating indirect potable reuse.
Indirect potable and non-potable reuse have been increasing rapidly in the United States. A 2015 report by Bluefield Research estimated that reuse of wastewater by municipalities would increase 61 percent by 2025. One-third of California’s wastewater could be reused by 2020, according to another 2014 report by the WateReuse Research Foundation, now called the Water Research Foundation. In other places, reuse is just a fact of life and a reflection of
geography. A third of Houston’s water, for example, comes from a reservoir on the Trinity River—half of whose water over the course of a year consists of wastewater originating upstream around Dallas-Fort Worth. Direct potable reuse, permanent and not temporary, is still a frontier. Just a few locations are fully embracing direct potable reuse as of fall 2018, yet the technology has been around for decades—first used in Africa. In Namibia, the City of
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