Recycled wastewater is not only as safe to drink as conventional potable water, it may even be less toxic than many sources of water we already drink daily, researchers say.

“We expected that potable reuse waters would be cleaner, in some cases, than conventional drinking water due to the fact that much more extensive treatment is conducted for them,” says William Mitch, senior author of the study in Nature Sustainability comparing conventional drinking water samples to wastewater purified as a drinking water, also known as potable reuse water.

“But we were surprised that in some cases the quality of the reuse water, particularly the reverse-osmosis-treated waters, was comparable to groundwater, which is traditionally considered the highest quality water.”

As drinking water sources become more scarce, the discovery is promising news for a thirsty public and utility companies struggling to keep up with demand.

Several potable reuse systems are up and running around the United States. The Orange County Water District has run the world’s largest water recycling plant since the 1970s. Water providers in Atlanta, Georgia, and Aurora, Colorado, also use potable reuse water as part of their drinking water supplies. Los Angeles plans to recycle all of its wastewater by 2035.

But decades of drought have intensified the urgency to make recycling wastewater as common as recycling an empty can of La Croix.

Water utilities, particularly those in the drought-stricken western US, are scrambling to find reliable water supplies. Traditional water sources from places such as the Colorado River and Sierra Nevada snowmelt have dried up. Instead, utilities have set their sights on potable reuse as a dependable water supply—one that utilities already conveniently manage and own.

“There are additional benefits beyond a secure water supply. If you’re not relying on importing water, that means there’s more water for ecosystems in northern California or Colorado,” says Mitch, a professor of civil and environmental engineering in Stanford Engineering and the Stanford Doerr School of Sustainability.

“You’re cleaning up the wastewater, and therefore you’re not discharging wastewater and potential contaminants to California’s beaches.”

Cleaning up recycled water is also known to cost a lot less and require less energy than plucking the salt out of seawater.

Read the full article about clean drinking water at Futurity.