November 24, 2017
The Most Valuable
Information Free To All

How California Is Learning to Love Drinking Recycled Water

It wasn’t too long ago that the so-called “yuck factor” associated with recycled water was a deal breaker for many communities. But new research shows that Californians are warming to the concept.

By Tara Lohan, News Deeply


WOULD YOU RATHER drink a cup of recycled wastewater or advanced purified water?

Samples of the water purification process at the Silicon Valley Advanced Water Purification Center in San Jose, Calif.Tara Lohan

Samples of the water purification process at the Silicon Valley Advanced Water Purification Center in San Jose, Calif.Tara Lohan

Actually, that’s a trick question – both terms are often used to talk about the same thing. But when it comes to public acceptance of the practice, the language you use makes a big difference. And so does education about how the process works.

Those are some of the things that have helped shift attitudes in California around potable reuse (drinking wastewater that has been purified for drinking). But it’s been a long road to get there and a few bumps remain.

Decades ago, the idea of treating wastewater to drinking water standards was met with resistance and it earned the unfortunate moniker of “toilet to tap” in 1995, which became widely touted in defeating proposals to purify recycled water for drinking in Southern California in the 1990s.

But Orange County paved a different way forward for California by using indirect potable reuse – treating wastewater to drinking water standards and then putting it back underground to mingle with water in the aquifer before being pumped back out for drinking.

Add to the equation another multi-year drought (just entering year six) and increased pressure on water sources from climate change and competing interests, and many Californians now seem ready to welcome recycled water into their homes. San Diego and Silicon Valley are both on their way.

In January, the water technology company Xylem conducted a survey of 3,000 Californians to gauge their support of water recycling. Water recycling can mean water treated for non-potable purposes, such as industrial uses and irrigation, but in this survey it was defined to mean wastewater that had been treated and purified for drinking.

Of those surveyed, 42 percent were very willing to use recycled water in their everyday lives and 41 percent were somewhat willing. The numbers increase with more information. The survey found that 89 percent of people were willing to use recycled water after receiving information about how the treatment process works.

The findings are similar to what Santa Clara Valley Water District has found as they have tested their customers on the concept as well. The water district has a facility, the Silicon Valley Advanced Water Purification Center, that can treat wastewater to drinking water standards, but currently the water is only used to supplement recycled water for non-potable uses such as irrigation. In the near future (likely the next two to three years), the agency may be using the water for indirect potable reuse to supplement groundwater for drinking.

A view inside the Silicon Valley Advanced Water Purification Center in San Jose, Calif. (Tara Lohan)

A view inside the Silicon Valley Advanced Water Purification Center in San Jose, Calif. (Tara Lohan)

A survey the agency conducted in Santa Clara County in 2010 found that initially people were pretty opposed to the idea of one day drinking recycled water – only 31 percent were in favor of it. But after being read information about how the treatment and purification process works, 53 percent were supportive. And then after being given additional information about why it’s good for the environment and helps support groundwater supplies, support rose to 69 percent.

“What we learned from that is with enough information and education you can change people’s understanding and perception,” said Marta Lugo, a public information representative of Santa Clara Valley Water District. Since education is key, in 2014 when the water district opened their water purification center, they immediately kicked off a public tour program.

The results show that seeing is believing. Visitors are asked to take surveys before and after the tour. When asked how they feel about using advanced purified water to replenish groundwater to augment drinking water supplies, only 42 percent are strongly in favor of it before the tour. But that number jumps to more than 98 percent after the tour.

Similarly, before the tour only 52 percent feel the purified water is safe to drink, but after the tour 97 percent of respondents feel it’s safe. And the hardest thing to get people on board with — direct potable reuse (pumping treated water directly to their homes) – goes from only 36 percent strongly supporting before the tour to more than 98 percent after the tour.

If seeing is believing, then tasting usually seals the deal. Lugo said an open-house event last October drew 900 people from the community, and more than 90 percent took a taste test. “Many were surprised when they saw, smelled and tasted it,” said Lugo. “If people see their neighbors taking a taste, or their friends and peers, they get over a psychological barrier – it becomes normalized.”

The facility doesn’t offer taste tests on all their tours now, however, because it isn’t regularly treating the water all the way to drinking standards since it’s currently just used for non-potable purposes.

But the water agency is proactively taking their message out into the community since the majority of the county’s 2 million residents won’t be able to visit the purification center. Lugo said they set up tables at events like Earth Day and have launched a speakers bureau to pitch their recycled water to neighborhood, rotary and professional associations. And a bill written by area assembly member Rich Gordon was recently signed into lawthat would allow facilities like Santa Clara Valley Water District’s to bottle their purified drinking water and give it away for free for educational purposes.

“It’s great, we are very supportive of that,” said Lugo, but added, “It’s tricky because for us, we haven’t explored the idea of bottling water, we have a policy of not promoting bottled water for environmental reasons.”

She says that acceptance has also grown during California’s drought, and being in Silicon Valley they are aided by having many tech-minded residents. But, a 2014 survey found that the biggest reason driving public acceptance of drinking recycled water is actually concern for the environment and the fact that recycled water is good for rivers, streams, fish, plants and wildlife, she said.

The language is also important, said Lugo. People are more accepting when it is referred to as “highly” or “advanced purified water.” It’s not just semantics but an important distinction. Many Californians are already familiar with recycled water that is transported in purple pipes for irrigation and industrial uses. They are also repeatedly cautioned not to drink purple pipe water. “We had to find a way to disassociate from that, because even though we are recycling water it is not the same water in the purple pipes, it’s a step ahead of that recycled water.”

Water from the Silicon Valley Advanced Water Purification Center goes through three main processes – microfiltration, reverse osmosis and ultraviolet light. If it was to be used for drinking water, it would also receive advanced oxidation.

Next year, the California legislature is likely to begin addressing regulations for direct potable reuse, which will give another boost to the idea of wastewater as part of the water supply. But it will likely be many more years before direct potable use is widespread.

Water agencies like Santa Clara Valley Water District are moving slowly. “It’s not an overnight process, it’s taken years of education,” said Lugo. “It has only been in the last year and a half that we have moved to aggressively talking about recycled water for drinking water supplies – either for groundwater replenishment or for direct use. It’s a process, but for the most part, the community has been very supportive.”