SJ plant turns bathroom wastewater into drinking water

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ByDavid Louie KGO logo
Thursday, November 20, 2014
SJ plant turns bathroom wastewater into drinking water
A plant in San Jose is turning wastewater from sinks, toilets, and washing machines into purified drinking water. But are residents ready to drink it?

SAN JOSE, Calif. (KGO) -- To help with California's drought, San Diego just gave the green light to spend more than $2 billion to turn wastewater into drinking water. In San Jose, a purification plant is already proving the concept works.

The Valley Water District, along with the cities of San Jose and Santa Clara, are already producing eight million gallons of purified water a day at the plant. That's water that originated in residents' kitchen sinks, washers, and bathrooms.

The $72 million advanced water purification plant went online eight months ago. It takes in wastewater that has already gone through two steps of treatment at another facility.

Then at the San Jose plant it goes through three more steps -- microfiltration that removes particles 1/300 the size of a strand of hair. After that, the water undergoes reverse osmosis. And the final step is exposure to ultraviolet light, a disinfection process.

"The water coming out of this treatment plant is already drinkable," said recycled water unit manager Hossein Ashktorab. "However, there's no regulation to drink it right from the treatment plant here."

But this demonstration project, like ones in San Diego and Orange County, hope to lead to widespread use of purified wastewater some day for drinking.

"It takes some getting over some hurdles in your mind to feel comfortable that this water is pure or maybe even purer than the water we're drinking from our tap today," Marty Grimes with the Santa Clara Valley Water District said.

Water customers confirm they're not ready to drink purified wastewater.

"Yuck, yes I do. I have a problem with that, the lack of confidence in how pure it would be," said San Jose resident Barbara Young.

It might be 10 to 15 years before we see widespread purified wastewater in our drinking supply system, but the people at this plant are so confident about the progress they've made, they say the water coming out today is drinkable.

For now, the eight million gallons purified each day are pumped through separate purple pipes to irrigate turf at Levi's Stadium and landscaping at office parks.

The hope is that once state standards are set later this decade, purified wastewater can help to make up for drought.

"Because it's drought-proof, it's going to be here for us in the driest periods," Grimes said. "Other water supplies may be more expensive, or they may not be available in those drought years."