Where did you come from? Where did you go?
You’ve finally done it! You threw a Ping-Pong ball into the fish bowl at a grimy carnival and with a “splash” you know you’ve won a pet. After about a week of good memories and weird smelling fish food, tragedy strikes. Sir Gillington goes belly up without even saying goodbye. So to the porcelain cemetery he goes, never to be seen again. But what happens after you give Sir Gillington his final ride? What happens after he passes through the Great Spirit in the Bowl?
Well if you aren’t living somewhere with a septic tank, most likely he travels down pipes to your local wastewater treatment facility. After getting there, the first obstacle in his journey is normally a screen that keeps out large debris -- ya know, trees, animals, dead bodies, etc. But after that, his journey ends rather quickly at another screen used to filter out rags, other pet fish, and anything else that someone may have flushed.
What happens next? Whelp, the inflowing wastewater is slowed down to allow sand and dirt to settle out of the system. From there, it goes to the clarifiers. There the *ahem* solids are separated from the liquids. The solids go off to a place where they are digested, processed, and can be used for fertilizer later. Yum!
After that, the wastewater flows into another tank where air is pumped in and the bacteria feast on the remaining sludge. The bacteria go to town and after they die and settle out, the water is almost clean.
Depending on where you live, sometimes chlorine, ultraviolet light, or ozone is added to the water for disinfection. From there, it goes back into a river ready to be taken up for drinking water downstream. Yes, you read that right. If your drinking water facility is located downstream from a wastewater treatment plant, there is a good chance that the water you use to fill the tank of your new fish friend (or for drinking) has been through a human system before.
While this is a generally safe process that has been going on for as long as you have been alive, some problems more recently have arisen. One of the more serious problems is that pharmaceuticals aren’t filtered out completely during the wastewater treatment process and can go into the natural water systems and impact the surrounding ecosystem, including your drinking water. While the amount of drugs in our drinking water is at very low concentrations, our fish and frog friends suffer the most and have problems with reproduction because there are no formal regulations to remove pharmaceuticals from wastewater or drinking water. While you can urge your senator for governmental action, the easiest way to help is to not flush your leftover prescriptions down the toilet.
So whether it's a dead fish or something more "man-made," you now know what happens when you flush the toilet. The next time you wave goodbye to whatever is in your wiz palace, know that it's about to go on the journey of a few people's lifetimes.