What happens to our poo? My incredible visit to the wastewater treatment plant.
When I was sixteen years old, I was one of about ten students that chose to take a class called Biotopics at my conservative Christian high school in Pennsylvania.
By that time, I had completed one year of earth science and a standard biology class. Earth science was okay, but there was a lot of chemistry involved, and I just didn’t have any chemistry with chemistry. (See what I did there?)
Despite rumors of inordinate numbers of quizzes, tests, and memorization, I still thought I’d be better off dissecting a cat than doing… well… whatever it is they do in chemistry.
Biotopics was fascinating. We dissected a cat, a shark, a fetal pig (of course), a fetal cow (wow), and the most fascinating thing ever: the pregnant uterus of a pig. I was one of a few students given the opportunity to carefully trim back the outer covering of the mother pig’s womb to expose partially developed fetal pigs inside their amniotic sacs. I was floored. I thought it was the best classroom experience I’d ever had.
Until we went on a field trip.
In the spring, our biotopics teacher, Mr. MacQueen, announced that he was taking us to the Bethlehem Wastewater Treatment Plant.
It sounded boring, but then again, I was the kind of kid who’d be happy to visit the local morgue if it would get me out of class for a day. I had my parents sign the permission slip and turned it in.
Soon enough, we embarked upon our trip.
On the bus, it was obvious that the students (including yours truly) had no idea what a wastewater treatment plant actually did. Imagine our surprise when our teacher told us we were going to see what happens to our poo after we flush it down.
Some people went quiet and looked at each other. I made a face.
“It’s interesting,” said Mr. MacQueen, looking straight at me, his Breathe Right Nose Strip pinched onto the end of his nose. “Trust me.”
When we arrived and pulled into the open gates of the Bethlehem, Pennsylvania plant, I was surprised to detect no smell of human excrement in the air. The parking lot and buildings were clean and there was no filth anywhere that I could see. I had expected to see groups of people dressed in coveralls, shoveling gigantic, stinky piles of poo from one section of an open lot to another, or burying it for it to rot into fertilizer, or whatever poo is good for. My expectations were not just wrong — they were absurd.
The director of the wastewater treatment plant emerged and met us at the gate — a nerd in a plaid shirt, khakis, and loafers. He welcomed us warmly, and I noted that although he had an unusually long nose, he was impeccably clean.
The director explained that a long time ago, wastewater would be pushed out into the ocean, rivers, and streams, and it would be cleaned by nature — flow, bacteria, etc. — and be clean enough for drinking, washing, and yes, flushing our poo. Today, we need our water cleaned and ready for its next purpose more quickly, hence the reason for the wastewater treatment plant. Basically, all of the processes that would happen in nature — filtering, breaking down materials, and having bacteria “cleaning” the water for us — is imitated at the plant, and further, the processes are sped up.
As the director toured us through different sections of the facility, he showed us where the sewage was pumped over screens and filters that pulled out anything that might clog up the works further down the line. “People flush a lot of stuff that won’t break down during our process, he explained.” I remember wanting to ask how many dead goldfish were pulled out each year, but I can’t remember if I actually did. This is the only part of the tour I could remember smelling bad… but it was never noxious.
Next, the sewage went into a grit chamber, which gave the material the chance to settle, and the heavier things — such as sand and small stones — would sink to the bottom. I remember the director saying that sand would not break down, and rocks… well, they’re rocks.
There was a final tank where the rest of the smaller sediment would fall, and then the wastewater — now called “effluent” — would move into the second treatment process.
Next we went to see these enormous holding tanks full of sludge, which was dark in color. The surface was not smooth; there were bubbles and glop on top and there was some kind of movement happening beneath. The director explained that in this tank the naturally occurring bacteria was working to eat away every piece of waste that was left over from the first treatment process. Under the surface there were machines that cycled the sludge to give the bacteria fresh material to digest.
After the bacteria had its way with the sludge, the sludge was no longer sludge. It was sort of the color and consistency of iced tea. The next process was to disinfect the material with chlorine bleach, which killed the bacteria off (So long, suckers — thanks for the free labor!) and resulted in clean, clear water. Then the water was pumped back out into a nearby stream, which fed back into the water supply.
Voila — clean, pure drinking water.
Anything that comes out of the material during the screenings is handled as efficiently as possible. Inorganic waste (things people flush down the toilet ) is pulled out during the screening process and taken out with the trash. The organic stuff is set aside and used for a million different purposes, including fertilizer and mulch. At that wastewater treatment plant, that material sits in a silo until it is put to good use.
In the end, what impressed me the most about the wastewater treatment plant was the coupling of the industrial and naturally occurring processes for a common goal. Until then, I had seen nature and industry perpetually at odds with each other. This was something new.
At the end of the tour, our little group was bused back to the school, and most of us spent the rest of the school day spacing out, as is typical of teenagers. In my mind I kept thinking how much happens around me that I know nothing about. My visit to the wastewater treatment plant humbled me, because I realized I never given a single thought or care to how our water gets recycled for many different purposes. Even as a teenager, I knew that I had been naive.
For every amazing life-sustaining process we know about, thousands more are hidden from view, which is why we tend to ignore vital infrastructure. We turn on the tap and clean water flows out. We flip a switch and our hall light comes on. We adjust the thermostat and the heat goes off. But when those functions fail, we have to deal with the reality of life. Real infrastructure failures in Puerto Rico and Flint, Michigan left people without basic life necessities. Without a doubt, they know the value of what they lost and had to rebuild… or now have to live without.
My visit to the wastewater treatment plant instilled a sense of respect in me that hadn’t been there before. A respect for resources, for processes, and for the people smarter than I will ever be who built incredible facilities that operate under the radar, ultimately improving our lives.
Esther Hofknecht Curtis, MSM-HCA is an independent writer living in Dover, Delaware. Follow her on Facebook at https://www.facebook.com/TheArdentReader19977/.
Did you like this article? Check out some of my others, below!