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Melissa Harris-Perry: This is The Takeaway, I'm Melissa Harris-Perry. Right now, the American Southwest is experiencing one of the worst droughts on record. The past 22 years are considered the worst dry spell in 1200 years.

Speaker 2: Unprecedented water restrictions are being ordered for 6 million SoCal residents as the Metropolitan Water District declares a drought emergency.

Speaker 3: The state's reservoirs are alarmingly low.

Speaker 4: About 80% of New Mexico is facing extreme drought.

Speaker 5: Cuts in water delivery to both Arizona and Nevada will happen next year.

Melissa Harris-Perry: Since much of the west is experiencing this mega-drought and many Californians face water restrictions, conserving water is an important step, but while conservation may mitigate water shortage, it's not a permanent solution to the problem of limited sources of water, especially in Southern California. That means, we're going to have to get inventive.

One solution to creating new sources of drinking water could be using recycled wastewater. Yes, recycling the water from our sinks and showers and even our toilets to be used as drinking water. I get it, this might seem like an unsavory solution to the water rows, but this process is already being used around the world, and even in Orange County, California which has the world's largest wastewater recycling facility. Could this be the future of our drinking water? I spoke with Dr. Daniel McCurry, Assistant Professor of Civil and Environmental Engineering at the University of Southern California.

Dr. Daniel McCurry: Not all water that we treat and produce is necessarily potable. Especially on the West Coast, you may have seen purple pipes at some point especially next to a golf course or something like that. That's what we call non-potable recycled water, that's treated to a lower standard because it's only going to be used for watering grass and things like that, but contrast potable means it's safe for human consumption.

Melissa Harris-Perry: Are there the same standards everywhere for what constitutes potable water or is that a state-by-state thing?

Dr. Daniel McCurry: It depends. If you were talking about tap water, like ordinary tap water that we would make out of lakes or rivers or groundwater in most of the US, that's regulated by the federal government. The EPA has standards for more than 80 different chemicals and pathogens for instance and the plants will have to test for these things and make sure that they're below the regulatory thresholds.

For recycled water on the other hand, right now, it's really a state-by-state framework. There's not recycled water plants in every state so you probably wouldn't find regulations for it in North Dakota or something like that. Each state sets their own rules up. Although, a lot of them look to California. We have the largest water reuse plant in the world here and are seen as a leader in the area. I suspect that any future, let's say nationwide water reuse regulations might look like California's.

Melissa Harris-Perry: All right. Now, before we get to the wastewater, I want-- because I don't think people always know even where their tap water typically comes from. When you ask people, where does your water come from? They're like, "The tap."

Dr. Daniel McCurry: Of course.

Melissa Harris-Perry: It's like right there. Help us to understand, even if we're not talking about wastewater, if we're talking about maybe more what we'll call traditional sources, how much work has to be done to go from that source to potable?

Dr. Daniel McCurry: Quite a bit. In places like California, especially Southern California where we don't have a whole lot of water that naturally falls here, we use a lot more water than nature provides, first we have to bring it to ourselves. In Southern California, about 90% of our water is imported from hundreds of miles away through a huge, impressive system of aqueduct that's ultimately filled by snowmelt for the most part.

In maybe the eastern half of the country, that's not such a concern, but in much of the west, water has to travel a long way, that might involve pumping it. For instance, in Los Angeles, our water has to go over a 2000-foot mountain pass which consumes an enormous amount of energy.

Melissa Harris-Perry: After it's come that long way, after it's consumed this energy, then what does it take to get it to a drinkable tap water stage?

Dr. Daniel McCurry: Sure. There's a fairly standardized set of processes at this point that are used for tap water production from raw surface water in the US. First, we often add a chemical called a coagulant to make particles, it could be dirt, could be bacteria, anything that's a particle floating around in the water, we want to get rid of that first.

We add a chemical called a coagulant. It's often based on aluminum or iron and that causes the particles to stick together and become larger. Once they're large, they'll settle out more quickly if you just hold the water slow in a big tank. After a sedimentation step where those particles are allowed to settle out, there's typically then a filtration step after that. We filter out any remaining particles and then the last main step is disinfection. That's often done in the US, it's just chlorine bleach or sometimes things like ozone or UV light can be used as well.

Melissa Harris-Perry: Now, let's get to the one that everybody on my team since we've started talking about this, has been calling poop water. Help us understand what is wastewater and why in the world would we want to recycle it?

Dr. Daniel McCurry: Sure. Well, the reason we would want to recycle it is because it's there. We're simply running out of water in many parts of the country and world and when the well runs dry, you'll drink just about anything. To answer your question maybe more directly, what wastewater is, it's a polite term for sewage and it's what gets flushed down the toilet, but also what goes down the shower drain, what goes down the drain of businesses, and things like that.

When that enters what we call the wastewater treatment plant, the goal of that treatment is just to raise the quality of the water up to a level where we can safely put it in the environment. It goes through a few processes to remove a bunch of chemicals and things like that from the wastewater, and then at most wastewater plants that just get sent into the environment which would typically mean either a river or an ocean or something like that, maybe a lake if you're on The Great Lakes.

Then if you're interested in going from that then to making drinking water out of it, we have this middle step where we close the urban water cycle if you will. The classical paradigm is we have a river, we take the water out, we make tap water out of it, it becomes wastewater. That wastewater gets treated and discharged downstream into the river.

In closing that cycle, what we're doing is instead of just putting it back into the environment, we're going to take that treated wastewater effluent, which is again only treated to a level for safe ecological discharge, and then we subject it to some very, very intense treatment processes before it then goes essentially to the front of a drinking water plant, or in some cases is put into something like a groundwater aquifer, the wet dirt underneath the ground where groundwater lives so that can be pulled back out and treated as future groundwater.

Melissa Harris-Perry: Right now though, where we're sending wastewater, does it ever end up getting recycled one way or another?

Dr. Daniel McCurry: Absolutely. Nearly all water is recycled depending on your definition of it. For instance, there's a lot of good examples in the US of this. Pittsburgh, for instance, gets water out of a river, treats it, uses it, it becomes wastewater, they treat that wastewater and send it down into the Ohio River. Now, of course, downstream, there are more cities.

For instance, a couple miles down the river or a couple hundred miles rather, when Cincinnati gets its drinking water out of the Ohio River, a certain percentage of that is Pittsburgh's treated wastewater. We call this De facto reuse and has been happening essentially since the dawn of time. There are many other even more extreme examples.

For instance, in Texas, the Trinity River which flows from Dallas to Houston and supplies some of Houston's drinking water, before wide-scale human civilization, that river used to be dry during certain parts of the year, and now it's not because it's full of Dallas' treated wastewater. If you're living in Houston, you're doing quite a bit of drinking recycled wastewater whether that's acknowledged or not.

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Melissa Harris-Perry: We've got to take a quick break. We're on the future of drinking water in just a moment.

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Melissa Harris-Perry: This is The Takeaway, I'm Melissa Harris-Perry. Now, parts of the world including Southern California are running out of sources of drinkable water.

Speaker 6: My God.

Melissa Harris-Perry: But don't panic. One solution might be closer than you think, recycled wastewater. We ask you if you'd be willing to drink recycled wastewater if it were treated and safe and we got a mix of responses.

Steve: Steve in Phoenixville, PA. There's inevitably going to be a water shortage and if we can recycle water, then I'm all for it. I'll be first in line to take a big gulp.

Speaker 7: Heck no, not drinking that stuff ever.

Jodi: Hi, my name is Jodi and I'm calling from Burbank. I'm not sure how I feel about reclaimed wastewater, but I suppose if I was drinking it, I just wouldn't want to know about it.

Mary: Hi, my name is, Mary I'm calling from Oakland with feelings. The idea sounds disgusting. I also think that before we are having to drink our wastewater, we outlaw lawns, watering grass, and other non-native and non-edible plants.

Melissa Harris-Perry: Let's get back to my conversation with Dr. Daniel McCurry. He walked us through the environmental effects of what we've been calling poop water.

Dr. Daniel McCurry: Of course, most places would rather use a traditional water source if they can for all their water, a river or groundwater or something like that. Once that option is off the table, and in a place like LA, if we wanted more traditional water, we would have to go find it ourselves. We are already maxing out what is provided in these aqueducts.

We'd have to, I don't know, build an even longer aqueduct or something like that. Once we've exhausted our traditional water sources, the main two things that we can turn to are either seawater desalination or wastewater recycling and wastewater reuse is a much greener option for a couple of reasons.

One is that seawater desalination, meaning making ocean water into something drinkable into fresh water, consumes an enormous amount of energy. It just takes a lot of pressure to push salt water through those very tight reverse osmosis membranes to get fresh water on the other side. Recycled wastewater consumes a lot less energy to produce than desalinated seawater. The other reason why wastewater reuse is greener as an option is because when you desalinate seawater, people typically picture you're taking a gallon of seawater and turning it into a gallon of fresh water and a little pile of salt.

What actually happens is you take that gallon of seawater and you turn it into a half gallon of fresh water and a half gallon of double salty seawater that we call brine. Then that brine has to be disposed of. You might think in a place on the coast, you could just put it back in the ocean, but the organisms, the marine life in the ocean aren't used to double salty seawater. It can create dead zones if we discharge that brine in a careless manner.

Maybe a more extreme example if you're further inland and there's nowhere to put it in the ocean and so then you have to think really carefully about what to do with that brine. Wastewater reuse by contrast forms much less brine, just because there's a lot less salt to get out of it.

Melissa Harris-Perry: Yet, no matter how you say it, no matter how much science there is, there's also this human-discussed factor that wells up in us when we think about using tap water, maybe one thing to water the golf course with it, maybe one thing to use it to even to wash my clothes with. If you talk to me about drinking it, it feels icky. How do we get past that?

Dr. Daniel McCurry: One option is just public outreach campaigns to educate people that in a sense, all water is recycled. The De facto reuse example with the rivers I was talking about earlier can maybe change people's attitudes about this. Also, just recognizing all water used to be dinosaur pee. It's all been on the earth for millions of years. It's gone through somebody's body at some point in the past.

I really think that we need to start thinking less about where water came from and more about what's in it. I think the other option is for the water recycling plants, as they open, to be as public-facing as possible. They've done a really good job of this at Orange County Water District's Reuse Plant, which is the largest in the world. It's the cleanest water treatment plant I've ever been to. They have public tours pretty much every day. You can see all the treatment steps that go from wastewater to something that's drinkable.

At the very end of the plant, there's actually a tap with a big stack of cups right there. They almost dare you, just go for it. I think just seeing how it's made and where it comes from will do a lot for many people to alleviate those concerns.

Melissa Harris-Perry: For folks who have been following various water crises, whether it's the Flint water crisis, whether it is the realities of contamination, and this push for clean water, the notion of clean and drinkable water as being a human right, our acknowledgment of how difficult it is to get this kind of water in various parts of our own country and around the world. How then to convince me that wastewater recycling is moving me away from a Flint problem as opposed to towards it?

Dr. Daniel McCurry: Maybe one answer is that recycled wastewater is subject to much tighter scrutiny than just ordinary tap water production because of this problem of public perception that it's gross. California, for instance, they're in the middle of writing their regulations for so-called direct potable reuse right now, which is where the recycled wastewater goes directly to the drinking water plan. It doesn't go back in the environment first.

It is a very long public-facing process where these rules are made. You could Google the draft rules right now. They're still writing them and finalizing them but they're making a great effort to be transparent about it. The other thing is to recognize that part of the problem in Flint was technical because there are ways, relatively easy ones, that we can control something like lead corrosion.

That just wasn't done when the city switched from one source of water to a different one because they didn't have the right level of expertise, I suppose, or maybe deliberately ignored certain experts who told them how to control that lead. I think that the key takeaway there is through engineering and through technical expertise, as long as we take it seriously, we should be able to overcome any water quality challenge, as long as sufficient care is given to it.

Melissa Harris-Perry: If you were called by a municipal water board to help them think through how to be public-facing in this way, have you thought about what the name of your poop water campaign or wastewater recycling campaign would be? What would you call it?

Dr. Daniel McCurry: The term toilet to tap has been used for, I would say decades now, as a slander against water reuse. One starting point might be just reclaiming that. Maybe taking pride in the fact that we can take something like what gets flushed down the toilet and make it into something drinkable. I don't know. Again, people smarter than me at this problem have thought about it.

For instance, Singapore where a decent chunk of their water is recycled, they call it new water. That's maybe a way of removing the poop water connotation from it. Similarly, at Orange County, the plant I was talking about, they don't call that a water recycling plant, they call it the groundwater replenishment system. What they're saying is we're taking wastewater, making new groundwater to put back in the ground to replace all the groundwater that we took too much of many decades ago unsustainably. Maybe just through some clever terms or phrase like that, you can shift perceptions a bit.

Melissa Harris-Perry: I love this. Either you go with euphemisms or you go right for it, toilet to tap. Americans, we're so badass, we can take our water from toilet to task. I got to say--

Dr. Daniel McCurry: Exactly. They do it on the Space Station. That's one of the coolest things we've built.

Melissa Harris-Perry: Oh, pause. Say one more beat about that. What's happening? The astronauts are drinking this?

Dr. Daniel McCurry: For sure. Water's been recycled on the Space Station for, I suppose decades now.

Melissa Harris-Perry: I suppose it hadn't occurred to me where they get their water in space.

Dr. Daniel McCurry: There's no rivers on the Space Station or on the moon or anything. It has to go around in the same cycle many times.

Melissa Harris-Perry: Oh, that's actually very helpful. Because if there were rivers in space, we would just probably go colonize and then pollute another planet real quick.

Dr. Daniel McCurry: We would've built an aqueduct to space by now if there was a big river up there.

Melissa Harris-Perry: Definitely, there'd be a huge Mars to US pipeline that would be much harder to actually stop the construction hub. Dr. Daniel McCurry, Assistant Professor of Civil and Environmental Engineering at the University of Southern California. Thanks so much for joining us.

Dr. Daniel McCurry: Thanks for having me.

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