California Program Makes Toilet Water Drinkable
STEVE INSKEEP, host:
You just heard a reference to people going two days without water. That touches on one of the major issues of our time. And in this country, Southern California faces a water shortage. There's a ribbon-cutting ceremony there this morning for a project that could provide some relief, a massive new water purification system. It is cause for a celebration, although it sounds a bit unsavory to some outsiders because this half-billion-dollar project gets drinking water from the toilet.
RENEE MONTAGNE, host:
Yes, this plant is transforming millions of gallons of sewage into pure turquoise water on its way to the taps of Orange County. The program manager of the county, is more neutrally named Groundwater Replenishment System, is Shivaji Deshmukh.
Mr. SHIVAJI DESHMUKH (Program Manager, Orange County Groundwater Replenishment System): Good morning, Renee.
MONTAGNE: Now, before I get into this new plant that you've got there and what it exactly does, was all that sewage water being sent out to the ocean before?
Mr. DESHMUKH: That's correct. It actually was being sent to the Orange County Sanitation District, our partner in this project. And they were treating it and discharging it out into the ocean.
MONTAGNE: So, lost, really, in a sense.
Mr. DESHMUKH: That's how we view it. We view waste waters as valuable resource. And by us purifying it, we're able to create a new drinking water supply that's reliable and drought-proof.
MONTAGNE: Now, it's been dubbed toilet to tap - this project - but, thankfully, it isn't that straightforward at all. What, in fact, is the journey that this sewage water takes before anyone can put it in a glass and drink it?
Mr. DESHMUKH: Starting from the Orange County Sanitation District side, they treat it twice. That water, then, is discharged to the ocean. This is where we step in. The Orange County Water District takes a large amount of that water enough to produce 70 million gallons a day. And we send it through three processes: microfiltration, reverse osmosis and ultraviolet light with hydrogen peroxide. This is the same technology that bottled water companies use.
After that, this water doesn't actually go to the taps, as the toilet to tap implies. It actually goes in the ground where it'll stay for at least six months to a year before being pumped out of the ground by the cities and agencies for our customers.
MONTAGNE: So it sounds like, by your description, sparkling water.
Mr. DESHMUKH: It is, to the eyes. It's very pretty. It reflects a lot of the light but has a very tropical feel to it. But that's just the view; the actual water quality is superb.
MONTAGNE: Still, how do you know, for certain - for certain, for certain, for sure - that the water is safe?
Mr. DESHMUKH: We have a rigorous testing program. The heart of this process is reverse osmosis. You're actually taking the dissolved salts or minerals out of the water. It's the same technology used to desalt ocean water. So if you're taking out that small amount of constituents in the water, you are taking out all the other organics, the pharmaceuticals, anything else that's in the water.
But we have a third step, which is ultraviolet light with hydrogen peroxide, which is designed - if we did find anything that was able to get through, this step would be able to address it. And we're not saying that anything is getting through our treatment process right now.
MONTAGNE: Now, all this is very convincing in this conversation. I'm wondering if this is the sort of arguments that you use to convince folks in Orange County to get over the ick factor.
Mr. DESHMUKH: If you explain to them that they're drinking waste water, of course they're going to be concerned. But if you explain to them the natural water cycle where we get our water from, and then you explain this treatment process, many people understand why we're doing it. So I believe people have gotten over that ick factor.
MONTAGNE: Well, there is one criticism that has been leveled at this project, and projects that might follow like this. And that's that dry regions should be looking more towards conservation efforts because it seems like trying to treat water so one can use more water can really add up.
Mr. DESHMUKH: We agree, conservation is an important part of your water supply portfolio. But that can only do so much for you. And we need to make sure that this water supply is available, but at the same time, get out there and promote conservation as much as we can.
MONTAGNE: Thank you very much for talking with us.
Mr. DESHMUKH: Thank you, Renee.
MONTAGNE: Shivaji Deshmukh is the program manager of the Groundwater Replenishment System for Orange County.
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