Wastewater treated at one of El Paso's four treatment plants is undergoing further purification at a pilot facility meant to clean it to drinking water standards. (Mónica Ortiz Uribe)
The search for new water sources is never-ending for growing cities in the desert Southwest. Traditional sources like rivers and underground aquifers are proving insufficient, so cities are turning to options that were once unthinkable — like “toilet to tap” recycling. A handful of cities in Texas are leading the way.
From above, the naked desert surrounding El Paso looks like a moonscape. It’s a treeless land of sand and shrubs that on average gets less than nine inches of rain per year. A century ago, the Rio Grande used to flood just east of downtown. Today growing regional demand has sucked the river bed dry.
When nature isn’t enough, people turn to technology.
A new purification system is being tested at one of El Paso’s wastewater treatment plants. For 50 years the city has used recycled wastewater, also known as purple pipe water, to irrigate parks, school yards and farms. Now the city wants to clean this water further and add it directly to the drinking supply.
“Basically it’s wastewater coming from homes, sinks, dishwashers, showers, toilets,” said Christina Montoya, marketing manager for El Paso Water Utilities.
Skeptics gave it the name “toilet to tap,” a phrase intended to provoke your gag reflex. But severe drought and dwindling water supplies across the Southwest are making the idea more palatable.
“In our very hot summer months, when people are really running their air conditioners, that’s when we get our highest water use,” Montoya said. “What happens is we come very close to not being able to meet that demand.”
Recycled wastewater could provide a 10 million gallon boost, about 6 percent of the city’s peak daily demand.
If approved by state regulators, El Paso’s project would be the largest in the country. Smaller Texas cities like Big Spring and Midland already have similar systems in place.