In many places, the biggest obstacles the new approaches face are regulatory, not technological. Only one state, Texas, now allows distribution of treated wastewater directly into potable water systems. As a result, two Texas cities, Wichita Falls and Big Spring, operate the only “direct potable reuse” systems in the country. Eleven states allow “indirect potable reuse” — the process that the Orange County Water District uses, in which treated wastewater is stored in aquifers before being distributed as drinking water.
Some non-potable reuse systems take advantage of lower purification requirements to provide water for industry, agriculture, and recreational facilities such as golf courses. But the cheaper cost of treatment is counterbalanced by the need to install separate piping systems for non-potable water. As a result, potable reuse, which doesn’t need additional pipes, is likely to flourish as the so-called “yuck factor” diminishes. Though California doesn’t allow direct potable reuse now, legislation passed last year requires state officials to issue enabling regulations by 2023. Those regulations are likely to serve as templates for other states, spurring adoption of direct potable reuse.
