How Wastewater Treatment Works

Have you done anything really weird in the last two weeks? Uh? I think a more legit question would be, what have I not done that's that's weird? What's the weirdest thing you've done? I'm trying to think like I shouldn't have said anything, because I really haven't done anything that weird. Have just been more like, um, I've developed this weird kind of I guess it's indigestion, which I don't get.

I have like an iron constitution, but I don't know if it's because I've been pounding vitamins lately and they keep lodging in this one spot in my esophagus. I think there's a weird bend in there somewhere um, and so I constantly feel like I've got some throw up just sitting in the middle of my chest. That's a new development. And I've noticed that when I don't take vitamins it still happens. So I'm I'm kind of up

the creek on that respect. And I know that's not doing anything weird, but um, I mean, I guess that aside from that and setting out box traps for coyotes and then eating the coyotes when I catch them, those are the two weirdest things, right, It's not bad. What about you. I haven't really done anything weird. I shaved. I shaved my head, but that was just because I was bored and hot. Nice Britney spears. Yeah, I mean

I haven't. You know, usually do that once a year, and I haven't done it in a few years for some reason. So, yeah, it has been a little while you've been rocking the grown out stuff. I know. I thought about shaving my beard too, just for funzies, but oh, I don't know. I think now is the time to try these weird things where no one's gonna see you for six weeks. Yeah. As a matter of fact, after we get done recording, I have a date with you me to go cut my hair because I've got the

COVID hair. It is really long, real, it's just out of control. You know that point where when you grow your finger nails out too far and they just turn that corner. Well, you wouldn't know it because you bite your fingernails, right. I quit biting my fingernails a while ago. Okay, so so maybe you've experienced this. There's a point, and it can It can happen within an hour where they're just too close to being too long, and then all of a sudden they turn this corner and you can't

go like another minute with them being unclipped. They just feel so gross all of a sudden. That's how my hair feels right now. I think the corner of your fingernails turn is called the tip of your finger start wrapping around. Yeah, man, so, um, I guess we're talking wastewater treatment then obviously with all this fingernail talk. Yeah, and I gotta say, um, who did this one? Did

Ed put this together for us? Ed did this with a high fever from what I understand, right, non non COVID related, we should point out, Yeah, he was just sick. He came through. He's doing Okay, he's on the mend um but yeah, he he turned this in. He's like, I I had a fever when I wrote this, So it might not make that much sense, but it did. I think it did, But I do we should say

if you work in wastewater treatment. What I did find out doing supplementary research was that there are clearly a lot of like there are almost fifteen thousand treatment plants in the United States, and they're clearly a bunch of different ways to do it. Because I saw a bunch of other different stuff. So let's just say what we're going to talk about is one way that it can go. Yeah, and we'll probably touch on some of the other ones that you know people use, but there's just no way

we could cover everything. And the other thing that I saw too, is there's a UM there's a real sentiment that the United States, in particulars infrastructure for treating wastewater UM is aging really rapidly, like we need to do something about it soon. I saw some some some watched all groups that we need to spend about two billion

dollars to upgrade our wastewater treatment around the country. Somebody else has six billion, but everybody's saying, wait, wait, wait, okay, that's great because we're using really antiquated methods that work. They work pretty well, but they're having a lot of trouble keeping up with um. The jones with the Jones is yes, because the jones is now. Because we live amongst like plastic everywhere they poop and pee plastic, they

throw stuff in antibiotics into their toilets. There's like a different world than the wastewater treatment plants where built to to handle like in the in the early and mid twentieth century. This is like a real opportunity to update our infrastructure as we rebuild it. So hopefully we'll be doing that hopefully. And you know what, two billion doesn't sound like a lot of money. I thought I was going to hear a number like one trillion. That's what

I would have thought too. I was actually kind of surprised. I went back and looked, and now they were talking about the wastewater treatment. So I don't know if it's I know that some of the technologies are very expensive, and maybe they're saying to rebuild as is, it would be two hundred and forty two six hundred billion, but maybe to to implement some of them more high tech stuff that that has come along in the last few years,

maybe that would be a little more high dollar. All right, well let's talk about low dollar, okay, by way of history, because at the beginning of wastewater treatment, well you can't even call it wastewater treatment, it was just calling It was basically like how we dealt with wastewater. We weren't

treating it at all. The very most rudimentary thing that you still can see in places our outhouses and latrines, which trine is just an outhouse or an outhouse is just a little trine with a little a little bit of privacy involved. Yeah, and you know what, I was looking up out houses. They're still around. There's like composting toilets and urine diverters and all sorts of like hippie stuff you can get into if you want. But one thing I kept seeing was, you know, like there's always

like a crescent moon cut out on the outhouse. Uh, yeah, I've seen those. It's like almost synonymous with an outous. It looks weird without one to me. So I looked it up and it turns out that back in colonial times, when um, there was a preliterate population. The crescent moon indicated that the outhouse was for women, and a star cutout indicated it was for men. The mystery from never had any any idea. Yeah, I learned that visiting Mount Vernon. That would be a good place to learn that for sure.

And George Washington's just had a big cutout of a marijuana leaf. He is only for him. Yeah, he'd come home from working in the fields and Martha would have a big bowl, big fat bowl waiting for him at the end of the day. Very nice. Uh So if you're talking about twentieth century, you would think like, yeah, but surely when we got to the twentieth century they

were really handling the sewage properly, not so at all. Um, just you know, it was well into the twentieth century when we still had suburbs with people living them in them with no sewer connections and outhouses and this was this is kind of hard to believe, but I guess in more rural areas. But that even says suburbs. Yeah, he made it sound like basically if you went into like um, I don't know, uh, Dunwoodie or something like that,

which is a suburb of Atlanta. Okay, you would have found out houses in the fifties, which maybe that's true. I don't know. I mean, if you think about it, a septic tank is really just kind of a fancy ladrine pit. Yeah. But it's interesting too because in uh like six b C. There were places that, you know, it's funny because it seems like there's a lot of advanced thinking in ancient times that goes by the wayside for just thousands of years and then it comes back.

But in what is now modern Syria, they actually had drainage pipes and stuff that fed wastewater from the outhouses, uh basically to the streets and rivers. So it's not like it was great, but it at least got it out of there. They didn't have a lot of follow through on their ideas. Great first idea, and then they were like, I just forget it after that pretty much. But hey, have you ever heard why things were like possibly more advanced or very advanced early on and then

they went dark for a little while. I feel like we talked about this before. It must have been the Enlightenment episode, because it's them. It was the Dark Ages the Middle Ages when the Church took over and basically said science can can burn hell. Amazing, that works. Yeah, it's crazy. And then the Enlightenment came along and said, no, science is back everybody, and we started to have like sewage treatment again, which I mean not coincidentally, that's around

the time we started taking sewage treatment seriously. And it wasn't just that we like got a lot smarter all of a sudden from the Enlightenment, which definitely was partially the case, but there were way more people, and so things like digging a hole in the ground, pooping and peeing into it and then once it got full, you know, burying it and digging another hole. UM methods like that

just became unsustainable. Or putting all of your sewage out into the street, it became unsustainable just because there were so many people. Yeah, and there was poop and p literally everywhere in the streets and the rivers and the lakes. And the first um sort of pushed towards treating the sewage was literally just because the smell. Eventually they were like,

this is terrible to live amongst. Maybe we could do something, Maybe we could throw some time or some charcoal or some sawdust on this stuff, and at least and it won't be safe, but we won't be like walking around gagging. Right, They're like, at least there are some sawdust on there. Some do something for God's sake. Sure, so they did do that, right, Um, But that's still it still wasn't enough.

I mean, people were still just they they I think in our Great Stink episode, Joseph basil Get was um just revered as a saint basically for saving people by you know, diverting um sewage into sewers away from people's drinking water and stuff. But even still, I think he was also responsible for helping design some of the earliest

wastewater treatment plants. But um still around the time and into the twentieth century, like there it was basically like here's a sewer, and then we're just gonna make the sewer come out downstream of our of our drinking water supply, and then problem solved. Sorry for Shelbyville, but exactly chew on it, Shelby Bill chew on our fecal matter. But but that was kind of exactly what happened if you were down river, downstream or you know, on the other

side of the lake from this area. You know, you got their poop in your backyard and you didn't want that. So eventually people started realizing that there are things that you can do to make water better and then put it into rivers and lakes and streams and even the ocean and seas. And that is basically where we're at right now with wastewater treatment, which is we poop and pee and we flushed stuff into the sewer, and then

the stuff goes into a wastewater treatment plant. We do some stuff to it, and then we put out slightly better than sewage water into the rivers and lakes and streams and and hope for the best. Yeah, that's right. Um. Some of the early things they also did was like fled afield with wastewater. Uh. This allowed sedimentation, which is the you know, the the feces basically settling, and then

actually the plants can help out. The plants take up all that gross stuff as water that they used to grow and it kind of traps it in there, which is nice, But then you sell those plants to Shelbyville. That's right, But it still didn't change, It didn't make anything less harmful. Uh. As far as bacteria goes. So that's why typhoid and cholera and everything was a huge problem.

And that's why wastewater maybe the biggest advancement in life saving device like that in penicillin our neck, neck and neck. I think, yeah, really, I mean, like just not being around water that contains all sorts of harmful bacteria that people pooped out. That's definitely going to improve your lifespan for sure. And that that whole thing about putting sewage onto a field and letting the plants deal with it

that's actually still around. That's like a that's a a sensible way to treat sewage because not only do the plan ants you know, take care of it, but as it trickles down through the soil to the groundwater, there's all sorts of microbes and minerals and all sorts of ions that pick up that harmful stuff and that actually

purifies the water. The problem is is once you get too many people, which can happen really quickly, that that soil and those plants get overwhelmed and a lot of bad stuff gets through and then you're polluting the groundwater. So as more and more people came along, we realized we had to come up with technology. We couldn't just rely on soil anymore. Yeah. Um, Massachusetts was a little forward thinking in a Woosta, mass in eighty nine, they

actually treated sewage with chemicals. Uh. And this is one of the first chemical treatments for sewage in America, I think. And that would cause these solids to clump together and then settle out like obviously the fecal matter. Uh. And that was good because bacteria is more uh more apt to cling to the poop than it will to stay

in the water. So that helped for a little while, and then for a long time after that they would just sort of dilute the water with uh, with clean water and say, well, it's this is as good as we can do basically, yeah, which I mean again, that's kind of what we're doing now. Whi's just the stuff we're putting out now is way better, um, way less harmful, and has way more stuff taken out than it did in the nineteenth century. But that's ultimately, that's what I'm

saying that we're still working mostly on those premises. One is that you, um, you you allow sedimentation to happen, which is like putting sewage over a field and letting the sediment settle, and then um, you use chemical or biological treatments to filter out stuff that is left over even after sedimentation. And that's again that's that's where we're at today. It's just the techniques were using are much

more advanced. Yeah. And I don't think we even said what wastewater is because I think a lot of people might think that wastewater is just something that goes down your toilet. Um. But wastewater is any kind of water affected by human use at all period. So there's uh, there's storm runoff. You know, rainwater is is wastewater. Um. And you might think like rainwater is beautiful, it falls from the sky and it's so clean. But this stuff

is running through cities. It's running, uh and especially in cities because there's not enough dirt and grass to soak it all up. So it's it's taking everything on every urban city street in America and collecting that and taking it with it. So fertilizer, pesticides, any kind of agricultural grossness, road kill, I mean, just think about every disgusting thing on the ground. And that's what stormwater is. And that's why stormwater is treated just like it is, which is wastewater,

whole possums, tons of possums. Guns Apparently what I saw one wastewater treatment explainer video and apparently a lot of guns end up getting filtered out in that first big filter. Oh my gosh, because I think people like, I don't know if they're just murder weapons that people throw down a sewer drain. I mean I would guess so, or at least crime weapons. You know, it's kind of scared. Yeah, you'd like to think like that happened one time somewhere,

not like that's a regular occurrence. That's nuts. Well, I mean, I say a lot of guns. I don't know how many guns, but it was enough for them to mention that guns show up quite often, right. Um, the one you were talking about, which is like all that that wastewater that goes down toilet's the poop and the b water that's actually called black water. I love that term. Man, I'm gonna make some black water. Yeah, that sounds like a like a hardcore cocktail that would involve Yeager Moister

and the Doodie Brothers. Let's work it out here, So Yeager Meister okay, um, a little bit of simple surah, very simple syrup, orange juice, fresh squeeze orange juice. How would that be with a beta? Be awful with the ager moister, of course, everything's gonna be off with you, ager MOISTERA um and then a little um, freshly muddled basil, little star and ease. Perhaps that's the black water cocktail. Oh my god, that's terrible. Gray water is not as

gross as that by any stretch. This is all the water. And we've talked about gray water in our eco friendly episodes because a lot of households will reuse their gray water, the water that goes down your sink or your shower. Um, a lot of individual households try to recycle their own gray water. If you're uh, you know, one of those four thinking hippie dippie types. Sure, if you've got a

composting toilet out house in your backyard. Yeah, but generally there aren't like big cities with huge gray water recycling systems yet to predict that in the next many years we will see those rise pretty pretty commonly. Yeah. I hope so I do too. I mean, it's definitely about time, like we waste water, like like it's nothing. Yeah, it's crazy how cheap our water is, especially in the States. You know. UM, there's also a couple of other things that if you're a waste I think they actually they

don't call them waste water any longer. They call it UM water resource reclamation plants, which I really kind of drives home what we're talking about a little more like this is this is something you don't want to just pe away, you know what I'm saying, Like, this is important stuff UM, And so they're they're starting to use like that kind of nomenclature to to indicate how important it is. But if you run one of these plants where you work at them, UM, a couple of other

things you're gonna be on the lookout for. UM is the um amount of pollutants that you're you have in your your water at any given time, the amount that comes through. And then in addition to storm runoff, black water, and gray water, you're also on the lookout for industrial affluent. And we should probably say real quick, um iffluent is what most people call wastewater all forms going into the

treatment plant. Yes, not affluent, no, no, UM effluent UH is is all wastewater if you're not in the know. If you are in the know, Effluent is what a water reclamation treatment plant puts out. The treated water is effluent. The all the untreated stuff that comes in is influent. That's right. But I think if we say effluent, we're probably just gonna be talking about it in general throughout

this episode. Yeah, and you know you mentioned industrial processes. Um, we should probably point out to that if you have an industrial plant manufacturing something, you probably have your own uh wastewater treatment system on site. You don't just dump all that stuff and say here, county or city deal with it. You have to clean that stuff first. Just in that really gross still gross water to the city. Probably depends on your mayor if he's spineless or she's spineless.

That's true, Mayor Quimby, he wouldn't. He wouldn't let it happen because he was spineless. He'd let it happen because he was getting kickbacks for it. Oh man, my favorite. I don't know even know if I can say this on the air. Okay, should I? Do? You know the line? My favorite? No? No, I wait to hear it. We'll

edit it out if you can't. All right, I can't remember which episode, but it was when everyone was freaking out about something and Quinby came up to the podium and said, calm down, everyone, I know, well, all we're all frightened and hawny. Yeah, that's right. I think that was the comment episode where the comment was headed towards Springfield. We're all frightened and horny, so funny. And then he introduces Professor Frank, and Professor Frank goes a good evening everyone,

and somebody stands up. He goes quit stalling what he goes, Okay, alright, sit down. Oh man, I missed that show. I do too. Um, you want to take a break, Yeah, let's take a break and we'll talk about how this stuff is treated. Okay. So we've basically we've talked a lot about wastewater up to this point, Chuck, and I feel like we should talk about it some more. Yeah, And uh, let me point something out too real quick, because Ed said in here that, um, wastewater treatment plants is not water that

you're going to end up drinking. That is not fully true. Um, in in water challenged places in the world. Uh, they don't like to call it this, but there are treatment facilities where they can go toilet to tap um places like Australia, Singapore, Namibia and then New Mexico, Virginia and California. Uh, they convert this stuff back into potable water. And it's pretty great actually because they've said, uh, it's shown that it actually has fewer containments contaminants than existing just like

what you and I are drinking in Atlanta. Let's say, yeah for sure, because they put it through such a rigorous process that from what I saw, Singapore actually has to remix it with rain water so that it'll get some of like the local minerals in in tar War basically because they strip it. They strip everything out. It's just like water molecules and that's it from what they do with it. And the one in Singapore I was

reading about. Did you read about that one? They seem to be like the leaders of the pack with this stuff. I think Singapore is especially challenge with water supplies. Yeah. So they actually, um, they came up with something called new water any W water and any W is capitalized. It is just a great great little like word and and spelling and everything. Um. But they also in addition to just coming up with like a bang up water filtration system or water reclamation system. They also had a

bang up PR campaign and got everybody behind it. You totally do. There was a town I can't remember in um I can't remember the name of it in Australia where like they needed to do this and it got sunk because some people started speaking out against it. All of a sudden, the city council started turning changing their minds. Um. I think Malcolm Turnbull forced a referendum to try to gain favor with some of the residents there and it

was just a big mess. But this paper was basically demonstrating side by side, you know, how bad it could be and how good it could be, but a big port of talking people into drinking water that somebody else peet out at some point or was contained poop at some point. Like you really have to be committed to it and have a united front and basically show the science saying this is harmless, there's nothing wrong with it. It's it's more pure than anything we're feeding you now,

So just try and Singapore was apparently very successful with it. Yeah, you really have to do that. Um I saw other places where they say they try not to make a too big of a show of it. But sure, I think the opposite. I think you really got to like educate people so they know that this this water is safe and taste fine, and I mean it's it's a miracle of of modern technology. You know, it really is.

It totally is. And um, I'm with you, Like, I think that's one of the things you need to be upfront and and transparent about not letting people find out the hard way. Yeah, a new water is you know, that's a great way to go because if you notice, new water sounds nothing like fecal water. No, no, it

sounds like new coke. Right that hit. Yeah, So um, all right, let's follow this uh this stuff like if you um, let's say it's raining one day, we're standing in a sewer now chuck, Okay, you don't have it. By the way, what we're about to describe takes about thirty six hours, depending on cool. So we're standing right outside of a sewage treatment plant, a water reclamation plant, and we are knee deep, our glosses are on and we're standing there and all this water is coming through.

It's raining, so there's um stormwater runoff. I'm sorry, I only have the one pair for him that's so gross. Um, and there's a possum floating by because because there's a stormwater runoff, maybe there's a gun over there. Um. People are pooping and peek, so there's black water all around us as well. People are taking showers, so there's gray water coming through. I could not stop thinking about corn when I was researching this. Yeah, like, what at what

point does corn get filtered out? So about we're about at that point. One of the first things that all this water is going to do is go through a um, a pretty good sized fence, right, and that's gonna hold

back all of the big stuff, the possums. The tree branch is probably a gun unless it's a real tiny little you know, old gambler's derringer, right, and all this stuff is gonna get caught up on a fence and eventually somebody's gonna come along and scrape it off, sell the gun, eat the possum, um, who do who knows what with the tree branch, and then um just basically

keep it clean for other stuff. That's that's the very first step that really before the water ever even goes into the plant, it's going to pass through one of these grates. Yeah, or there may be like a vertical conveyor system. So some so, some unlucky individual doesn't have to scoop pop poop possums and poop guns out of water. Right, A clean possum is bad enough, But one that's been bathed in black water, that's not good. Man. We're making jokes,

but God bless those people who do this work. You know. Oh yeah, for sure, for sure, hats off to them because again they're keeping all of us safe and healthy. It's right right, So well, no I'm keeping money. Um, So we've gone through that first grade. Now there's another series of screens that are gonna pick out smaller stuff like you know, bits of tire or little um car accident pieces that run off with the storm water. You know I'm talking about were like, you know, there's this

all sorts of glittery stuff in the road. All that stuff gets picked up and course saying that kind of thing. And now you're talking. Now you've got some water that's ready to be treated. Yeah. There there's uh something called a grit chamber. Uh. They can be horizontal rated or vortex um. The vortex ones are kind of cool ed called it a hydrocyclone. I think it's the same thing, and it basically just spins the water and slings all that grit and stuff, I guess a car accident stuff

right out to the side where it's filtered out. Do you remember at like the County Fair or whatever, that that ride that was like that? Yeah, Six Flags had. Yeah, God, it was called the what was it called? But yeah, it's spun and then the floor dropped out from under you. Yeah right, it was probably called the Black Water. I can't remember. I did not like it, though, so I loved it. Six Flags had one of those times. Yeah, they got rid of it pretty quickly, and of course,

you know, you always get these Six Flags rumors. The rumor was that some child didn't get slung out and like got trapped when the floor came back up, which may have been true for all I know, but I just I don't like a dizzying things. Yeah. The trick was to just keep your focus on something inside in the middle, like the person across from you who was moving relative to you, and that kept you from getting dizzy. Um. Okay, so yes, so, but you can if you were so inclined.

And also I have to say, like reading all of these different steps, I'm like, this would be kind of a fun ride actually, to like slide through here. If you're small, it's like you were just a little piece of car headlight. To take it all the way through, that would be pretty fun. So, um, now you've got water that's ready to be treated. It's been um, the grit's been taken out, the big pieces have been taken out,

but there's still plenty of stuff in it. And the water is very turbid, right, there's a lot of suspended particulate matter just kind of floating around making the water murky. And this is where it enters what's known as primary treatment, where basically, if there's any water reclamation plant anywhere in the world, it's going to go through this stage at

least the primary treatment. Yeah, and um, I think it's uh, you know, you think about during the daytime, there's a lot more activity, so uh, these facilities aren't meant to, um like, operate at full board during the day and then be cool at night. Like they depend on a

very steady flow. And you know, pollution can't all bum rush it when everyone goes and takes their morning poop so they have these um, these holding tanks basically where they can hold this stuff during the day that's coming in and just sort of balance it out and distribute it over a twenty four hour period so it's not

the system's never overwhelmed basically. Yeah, it's called flow equalization, where if you imagine this is a river running through they keep very tight control over the volume and the speed and the flow of the wastewater that's going through the plant, and so when that flow is exceeded, whatever is exceeded gets diverted off to one of these holding basins so that when the flow goes down, they can move some from the from the holding basin into that

flow to make it so it's steady basically twenty four hours a day. That's pretty ingenious stuff. If you ask me, I didn't know that it is. Uh. And then one more gross thing that we should mention. Yeah, we forgot this. Yeah, grease and fat um. You know, restaurants use grease traps, but there's still so much um industrial and consumer like, you know, think about anytime someone pours grease down their drain or oil down their drain in their house, which

you shouldn't be doing it. That stuff ends up in the wastewater treatment facility, and it all loves to hang out with each other and congeal up together. And there's something called fat bergs that form, and remember the one from London. Oh god, yeah, they're they're horrid. It's a it's a huge, sometime multi ton ball of fat and grease. And apparently they're really good at attracting um uh, flushable wipes.

Although you're gonna say the ladies, right, the ones that have like gold medallions and chest hair stuck to them, Yes, but the normal fat birds, the ones with glasses and buck teeth, they don't. So disco stew versus cletus a slight joke, exactly exactly. And I didn't know there's gonna

be so Simpsons heavy. I had no idea either, but but yeah, I remember learning about fatberg's back in I think it was two thousand and eleven something like that, where London had one and and they were like, everybody stopped flushing wipes, and um everyone said, no, you can just get the fat bergs out every once in a while. But yeah, that's that's horrid. But they have to get those out, not just because the fat brigs are so gross.

But like you were saying, that can really screw with the machinery in the UM in the water reclamation plant. So I guess that would be after grit potentially. Yeah. They go into these aeration basins and they basically just inject a bunch of air in the bottom of the tanks or not even tanks. A lot of these are

open air that you know, we'll mention that later. It uh, it just creates bubbles and it aerates the water and that kind of just works everything free where it can float to the top so you can just skim it right on off and slap it on a roll and go to town. Yep. It's a great Mayo substitute. UM. Okay, So now we finally enter this primary treatment. Although I would I would argue that removing grease and fat or I think the acronym is fog, fat, oil and grease UM,

that's part of primary treatment. But we'll say that it's step negative point five. We finally reached step one, which is where this turbid um uh water with all of this kind of suspended particulate matter in it is going to be dumped into a tank. Usually UM well, I can't say usually, but there's like two main versions that

I've seen. One is a big round one, um, where the water just flows into the middle and then just kind of um slows down as it reaches the outside of the tank the or the edges of the tank. The other is a makes a little more since it's almost like a big swimming pool where the water comes in one end and slows down as it makes its

way towards the other. Either way, the point of this is slowing the water down so that it continues to flow, but flows so slowly that all those suspended particles have a chance to settle to the bottom under gravity and that sedimentation like we talked about, you know, way back in the day, where they used to take sewer water and put it over a field as it was trickling through that soil under the force of gravity, that sedimentation. We do the same thing today, except we usually do

it in a tank rather than a field. And then we also may use some agents to speed it up, like flocculating agents, which is one of my favorite words, maybe a good band name, I'm not sure. Um. There's also coalgulating agents, which is a terrible band name, and they'll actually do what um, what they were trying to do with the grease, which is kind of fluff it up or make it attracted to one another and and form larger solids that are way easier to get out

of there. And after this primary treatment, the water looks pretty good, but you would not drink it because you would die almost immediately of a horrible, terrible death. Yeah. And the the key with these primary clarifiers, which are these main tanks that they go into it first, is there's something called settling velocity, and that's the speed at which the particulate is going to settle. And we mentioned

earlier the flow rate coming in. The reason they have to be just manic about how much stuff is coming in there is because your flow rate of the time can never exceed that settling velocity. So, in other words, the stuff coming in can't be coming in faster than all that nasty stuff can settle, right, right, And but that nasty stuff does settle, and it forms what everybody calls sludge. But what I saw, Chuck, is that it is not the term of art these days. The current

term is raw primary bio solids, formerly sludge. That's the full name of it r P B s are p B f s s Oh that those are different words, like formerly sludge is part of the name. Like they changed the name of sludge to raw raw primary bioa solids formerly sludge like Prince basically yeah, right exactly, the aret just formerly known as Frits oh man lright b yeah for real, Oh my gosh. So uh, things are gonna stink. There's no way to get around it. If

you've been to a wastewater treatment plant, it's gonna smell. Um. That's why they're usually not close to residential areas, although there is one in Atlanta or on the West Side that's just kind of right there. Yeah, I've never smelled it. I haven't either. Um, it may be capped. Like if you get complaints of odors, then basically, if you get enough of them, then the city says, all right, we gotta do something here. Yeah, maybe we need to put a put a roof on this thing. It can't be

open air any longer, or maybe we need it. And this is probably what they do. And the one on the west side is they they treat that air. They ducked it out and treat it. Uh you know, old school. Uh, they basically take a bunch of toilet paper rolls and stuff them with dryer sheets, like the old dorm trick. Oh, I remember we talked about that recently. I don't remember what episode though, how did we Yeah, yeah, um, yeah, I can't remember what it was, but yeah, yes we did.

But if you work in one of these plants, it's it's not gonna It's not like working at a tulip farm in Holland. You know, it would be a nice smell, although I don't think tulips actually smell, but yeah, I'm sure it's still better than whatever everybody at these reclamation plants are smelling. But you know what, tulip farmers and Holland smell great, right they do. They have a musky, earthy odor. So um, okay, so yes it smells. I thought that was a cute, hilarious little like sidetrack included

in this for us UM. But this water, though, chuck right. Once it's treated, primarily it looks fine, but it's not fine. And for a very long time, like that was the extent of water reclamation, you would scoop out the sludge send that that primary um primary treated water out to lakes and rivers, and then you go, jeez, why are

all these fish dying off? What's the problem? And the problem it turned out was that we really needed to add a second stage of treatment that even though you couldn't see the bad stuff in there anymore because you've taken it out, there was still plenty of microscopic material that could cause all sorts of havoc on the body

of water that you release this out to. And they're they're described by a term called um biochemical oxygen demand, which is the amount of basically living aerobic bacteria in this treated water and how much oxygen it will suck out of that body of water, growing like forming an

algae bloom. And then as the algae bloom uses up all the oxygen dies off, um the the bacteria that eats those use up the rest of the oxygen and kill off a lot of fish and a lot of other wildlife in that body of water that you dump that sewage into. And so as they kind of figured out that there's this this this stuff you can't see in there, that's still a real problem, We've added a

secondary form of water treatment and that's really improved things tremendously. Yeah, so let's take another break and we'll talk about secondary treatment and then eventually tertiary treatment right after this. All right, So where we left off was uh and and we should also say too that like there are probably out of the fifteen thousand treatment plants in the country, I'm sure there's are still some that stopped at the primary treatment. Yeah,

I'm I'm positive too. But which is like, you can't like that's that to me is an ecological crime. It's an environmental crime. Oh absolutely, because it's so damaging to two water resources. It's just and in wildlife resources too. It's just it should be a crime. It's not yet, but hopefully it will be soon. Oh absolutely. Um. So secondary treatment is key and if you're if you're working at a modern wastewater treatment facility, then you're definitely gonna

go with secondary treatment. I'm not sure the what year they started coming around it, um And actually I can tell you something. So yeah, they're the main process of secondary treatment is called activated sludge and it was developed starting in nineteen twelve. Okay, so there are still some that are behind the nineteen twelve barrier. Wow. Yeah, So in the secondary treatment This is where, um, it gets

kind of interesting in a chemical way. You talked about the algae blooms, which are no good, so to prevent stuff like that from happening. Um, what's going on in this water is they're all these uh what's basically going on is aerobic digestion. They're putting things in there that can eat this stuff. Right, it's crazy like that. It's beneficial bacteria to the rescue, which is just wonderful. Like

they're using. This is that biological treatment we referred to earlier where they're saying, hey, there's all this bacteria and all these other terrible um like little by products and things that we don't on and they're everything from like gasoline molecules to whatever um. And there are different types of bacteria, protozoa, even tiny tiny, tiny little invertebrates um that live in the water most most of the time

are microscopic and they'll eat this stuff. And if we feed them this treated sewage, they'll make it even even pure. And that's that's the secondary treatment, which I just love. And we've been doing it for over a hundred years now, well most of us have been, I should say, yeah, And it's crazy to think about. When you look at a wastewater treatment plant, they have about these cool mechanical processes going on, but they're also growing, essentially and uh,

living things there that are their little work buddies. They're their little cohorts that do part two. And they have to, uh, they have to foster life for these micro organisms, I assume on site. Right, Yeah, but from what I saw it, it's kind of like a self aiming thing. Right. Well, there probably are a few sea monkeys mixed in there. I wouldn't be surprised. But from what I saw, with activated sledge, you're actually taking bacteria that's already alive and

eating the stuff in the sewage. You're just fostering it by pumping air and more specifically oxygen into the mix, which mixes the stuff up but also gives them oxygen to like really kind of be powered by. And so

they really go to town eating this. So not only do they break down during this activated sledge process, these these beneficial bacteria not only break down the stuff you're trying to get out of the water, they also multiply and create more and more bacteria, so that part of the activated sledge processes after being treated for several hours, you move that treated secondary treated water out and then you take the sludge that you let settle to the

bottom and pump it back through for another round, because you've got all new bacteria that was produced in that last round. And so it's kind of like this nice circular closed system that is so effective. I saw that. Um. Usually at night they have to skim off some of the bacteria that's been produced that day because it's usually so successful. Yeah, and I think they even pay someone to stand there and go, what do you think of that?

How about one more round? It's a miracle. Every every six hours after treatment process goes through, they just shout, it's a miracle. So we're talking about like bacterial membranes, like a sheet of bacteria that might churn through this one of these basins, or maybe an algae sheet or something like that. And you know, you gotta, like you said, you gotta keep this stuff alive. So the pH is important, oxygen eating like you were talking about. The temperature has

got to be regulated. Um, you just have to make sure these these little uh, these little booger state healthy and happy. You want them to be happy as can be and as long as you're pumping oxygen there and making the pH the way that you want it or the way that they wanted, they're they're going to be happy and reproduce and multiply and go forth and spread

the gospel. All right, So that is secondary treatment, and that is apparently it gets to the point where the United States has said, fine, dump it in a lake, dump it in a river, dump it in the ocean. It's perfectly. But then if you're if you really want to kick things up a notch, you can go for a tertiary treatment. This is just showing off. It really is, isn't it. Another word for it is uh disinfection or

polishing um. And this is pretty interesting because you wouldn't know it, but there are tiny little things ranging from parasites to antibiotics, and we'll talk about all these a little more detail. To microplastics, like there are microplastics and some soaps or just larger plastics that break down and some of that stuff gets through these first two processes and there's actually plastic in the water. Yeah, I'm guessing Emily doesn't use plastics in the soap she makes for

Love Your Mama, Plastics, No, Um. But I had no idea until I read this that that was the thing. But it makes sense so like that that I guess the exfoliating stuff. It's not all crushed walnuts, shells or anything like that. Like it would make a lot of sense to use all of this waste plastic or it

makes sense, and I guess the strictly business sense. But these plastics that they can be filtered out, but they can also be broken down to this point where they're they're microscopic as well, and so if you're just doing primary treatment, you're sending a lot of those microplastics right out the other side, and that's allowed them to kind of spread throughout the entire food chain. I saw this, Um, I think it was a front line just the other night on plastics, and man, it was eye opening, Like

we need to do an episode on plastics. I've been wanting to for a while, but this one kind of lit a fire under my butt. Um. But it I mean, it's it's just everywhere, and so much so that not just washing up on beaches, but it's in the water we drink, right. So one of the things they figured out is there are types of bacteria that eat plastics. So now they're trying to figure out how to cultivate those bacteria. And that's another thing to what what we

were saying with that secondary treatment like activated sledge. It's not just one kind of bacteria. It's a huge microbiome of bacteria that eat all sorts of different things, specialize in all these different things. But when you have a big, huge, diverse colony, you can get that much more stuff out. And so there are some bacteria that eat my microplastics. Then I also saw and this to me is the future.

It's um ozone oh three, three oxygen atoms put together, and that's that from what I saw, Chuck, it handles every single thing that you would possibly want to get out of water. Yeah, so with ozone, what they'll do is they'll send it in a tetrical charge through the water and these O two molecules disassociate from one another and then recombined to form ozone oh three. And it's just a kind of a superhero occident that does a great,

great job killing bacteria. I saw it as more like a coked up John Belushi just running through a room or something like that. That's how I saw it, because it's like it just goes in there and and messes stuff up. Like anything it touches, it just starts to break down. UM. Because it's so reactive that it basically says, give me an electron, baby, and that whatever it just took an electron from starts to fall apart. Yeah. You can also chlorinate the wastewater. UM. You know we've talked

about chlorination before. Uh. It works pretty well, but it's not like a disinfectant. UM, and the chlorine itself can break down into toxic substances, which is not good because then you gotta go treat that other tertiary methods and that's no good either. That's right, like chloroform I think is a byproduct of it. And then there's UV radiation, which takes a ton of energy. Uh, it can be effective, but it's really expensive. Yeah it is, UM, but it does work. I mean most things do not stand up

very well the UV radiation or UV light. UM. We have one of those phone um cleaners, a UV phone cleaner. You have you seen those? Yeah? I saw those on Shark Tank many years ago. Oh yeah, So, UM, I can't tell if it works or not, but I think it's does. I realized it's kind of a matter of faith here, but it makes me feel good. Um. And then there's another one called reverse os moses, which I think deserves its own episode, or at least needs to

figure in like a desalination episode or something. But it is um basically using a membrane that is so small only water can pass through it. So when you push sewage or treated water or anything um through this membrane on the other side, water comes out. Everything else is

left behind. And what I saw about Singapore's new water is not only do they use that very expensive, very effective UV radiation, they also use reverse osmosis in addition to microfiltering to produce this new water, which is why it's like so pure that they have to add it back with you know, rain water to get some of the minerals back into it. Yeah, reverse osmosis works rejects I think nine percent of bacteria. Los Angeles and some other cities are using this, like we said, cities that

have water shortages. Generally, it really depends on not only this membrane but tons of pressure UM up to six hundred pounds per square inch, very highly pressurized, and if you want to get what they're calling i p R Indirect potable reuse, which is eventually you can drink this stuff. I seen all kinds of problem. I mean, I guess

this new water, that's what their aim is. But you you take your tertiary tertiary tertiary tertiary treated water, you hold that in a reservoir for a while, then it goes through osmosis, then it's treated with either UV or ozone or both. Then it goes back to a reservoir for about six months for just natural processes to go to go to work, and then it gets sent just through the regular standard water treatment that everyone else's water

goes through. Wow, that's like l A's doing that. I think if if you're doing i PR right, then you're doing many of these steps in concert with one another and then sending it through the regular system in the end. I'm sure there are different ways in different places, but uh, it's pretty amazing that you can you can drink water that goes down your toilet eventually, and it's probably better

than a lot of city water. Yeah, oh for sure. Um. One of the things that that got me chuck um was that we still do that thing where we take that sludge and spread it over um farmland, create those sewage farms. So everything's kind of come back full circle again. Um. And we also use semi semi treated water for like, um,

like like you're getting parks and stuff like that. So there's like a there's there's um a lot of good uses for for water that's not quite indirect potable reuse quality, but can it is still like good enough you just wouldn't want to drink it, yeah, or you can just dump it back into your local river lake or something

like that. Yeah, that's always great. And then the just lastly, real quick, UM, the future of this stuff that I saw is that they're getting so good at filtering stuff out that they're like, well, wait a minute, we're accumulating a lot of this plastic um, so let's start collecting it and selling it for reuse, right, which is which is wonderful because I mean, otherwise they're just diverting this

stuff to a landfill. Or they're getting so good at getting like phosphorus or nitrogen out, well, let's make a sideline of selling fertilizer to farmers or something like that. Um. Rather than adding more to the water supply, will just reuse the stuff that didn't get used the first time. And then um, they're also reusing cellulose fiber from used

toilet paper, and that amazing is amazing. So they're filtering out cellulose that was part of toilet paper at one point, and they're using it for everything from insulation to roadways I believe, which I didn't know they used cellulos and roadways, but by god they do now. So that's wastewater treatment. Everybody, one of those great engineering episodes that we do from time to time. I hope you enjoyed it. Yeah, I

got one more. We always like to think of our friends in New York because that's sort of the gold standard of huge city doing amazing things. And there are fourteen plants in New York City alone, and they how many gallons of water per day? Do you think they treat? Just take a stab? One point three billion gallons of water per day? Wow? I was apparently the statistic I saw said, if you that is enough over eight years to fill the entire Dead Sea with toilet water. Wow,

which you should not do. Don't do it the dead Sea special. Do you got anything else? They've got nothing else? Uh, Well, if you want to know more about wastewater, just show up at your local wastewater treatment plan or you're sorry, your water recap water resource reclamation plant and they'll probably

give you a tour, especially if they're friendly types. And since I said that, it's time for the listener, mayo, Yeah, show up and say I want to see the artists formerly known as sludge, right but also doing a really like kind a hostile demanding way. Yeah. Absolutely, Um, all right, I'm gonna call this from a teacher. We love hearing from our teachers here during the worldwide lockdown. Now that

Georgia is finally on board. Yeah, they just found out that you could be a contagious and not show symptoms yesterday. I'm so angry about that. It's nuts. My daughter literally knew that before our governor said he did. Yeah, for probably a good month, I would guess. Probably. Yeah, you should listen to our show. We talked about it last week, well in real time, weeks ago by the time this comes out. All right, So this is from a teacher named j Alexander in the mathematics department at l h S.

Good morning, guys. I wanted to thank you for the distraction episodes. As a teacher working from home, I've been helping my one and thirty plus students and their parents navigate this challenge while also making sure my two biological kiddos are doing their work as well. With the governor closing schools for the rest of the year, I woke up pretty sad this morning. I'm sad for my seniors. We didn't know the last time we were together would

truly be the last time. I was thinking about that the other day too, man, Like, that's just it's all sad. But seniors and prom and last day's school and all that fun stuff is just to to miss that as it just sucks. Yeah, it really does. Do you know what they're gonna do? Is it like you're just gonna continue on the rest of the year from home and still graduate on time. I think everyone's just trying to

figure this out in real time. Man, My own daughter is graduating from her preschool, so she's not going to see a lot of these kids ever. Again, just super sad. That's sad, but also congratulations. Yeah, well they're they're doing these uh two times a week, these zoom meetings, which is kind of fun to see all these kids on there, I'll bet just crawling around not paying attention. They're actually

pretty locked in. It's it's very impressive. Oh really, Yeah, their teachers are on there and they kind of are in a rhythm. It's it's kind of cool to see. That's cool, all right, so let's just continue here. I'm sad for my own kids who won't see their friends and teachers for the rest of the school year. I'm sad for all my coworkers who are retiring this year. They didn't plan for it to end this way, although quite frankly, they may be pretty stumped early retirement. Uh,

they're definitely silver lining, zough. I'm seven months pregnant and don't mind working in my pajamas. The weather is great in your podcast is keeping me sane. So thank you all so much for being my normal in this twilight zone world. I pray that you and your families are safe and healthy. And again, that is J Alexander the letter J from the Mathematics department at l h S and right back at you two from us to you, um, thank you very much, and thanks to everybody out there

sending us good vibes. We're sending them right back out to the entire world. It's basically like a d light concert in here. That's right. If you want to get in touch with us during this weird time or any time, you can send us an email, wrap it up, spank it on the bottom, hit it with the lysol wipe, and send it to Stuff Podcasts at iHeart radio dot com m H. Stuff You Should Know is a production

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