Try not to think about this the next time you go swimming in a public pool. According to one Canadian study, there’s an average of eight gallons of urine in a typical 110,000-gallon public pool. Considering the general size of the human bladder, which averages about .3 liters per pee, that must mean the urine came from about 100 people!
And what about that strong, chlorine pool smell? That eye-watering chemical odor must mean they’re clean, right? Sorry, but that’s not chlorine you’re smelling. The smell is trichloramine, which is a gas created when chlorine reacts with the chemicals in your urine or other biological matter in the water. The stronger the “chlorine” smell, the more urine and other biological matter like pee, sweat, skin cells, etc. are breaking down in the pool.
So, what happens to all that pee in the pool? The answer depends on whether the pool is ever totally drained. Everyone treats their pool differently: Public pools sometimes change their water twice a year; others do it every five years; and some never do it at all, because of the price of water, maintenance costs, pool shut-downs for residents, and the potential for pool “popping” out of the ground. These can all cost an HOA money, which can be passed on to the residents in that community.
But let’s say a pool isn’t immediately drained. Then the chlorine changes the urine into different chemicals. Some of it turns into a gas and blows away with the wind, but it also turns into nitrates. And while nitrates make good plant and algae fertilizers, it does nothing for humans — except accumulate in a swimming pool until the water is completely replaced. They can also be removed by treating the water with phosphate remover which bond to all the nitrites and phosphates and allow them to be captured in the pool filter. They can then be sprayed off of the filters or chemically removed from the filter. Of course replacing the filter is arguably the best way to start fresh.
Not surprisingly, pee is far from the only unwanted substance in the average public pool, so let’s rank them in order, from “harmless” to “maybe just relax on the pool deck for the afternoon”…
Realistically, unless you’re in a tiny, plastic, backyard kiddie pool, the amount of adult beverage that might end up in a pool is infinitesimal compared to the amount of water diluting it, so it’s nothing to worry about.
Sweat, Hair, Skin Cells, Etc.
This is one reason those signs by the pool that nobody ever reads tell everyone to “shower before getting in.” Sweat, skin cells, and whatever else is on your body could turn into disinfectant byproducts when they mix with the pool-cleaning solution. Not much you can do about this, though, aside from forcing everyone to shower.
It’s in there, whether it’s from someone’s wound, an erupted zit or menstruation. And blood can certainly cause nasty disinfectant byproducts. But let’s be real: We’re not talking about “horror film” levels of blood here. And if we are, maybe go swim somewhere else?
These also mix with disinfectants, and according to science, can create some nasty toxic precursors. We already know that sunscreen contains a bunch of mysterious chemicals. The state of Hawaii recently banned sunscreens containing two kinds of chemicals because the pale folks who slathered or sprayed them on and went snorkeling were unwittingly killing all the coral. If you can see a bunch of sunscreen slime skimming on the surface of a pool (kiddie pools often have this), that’s not a good sign.
If you see a child wearing a diaper in the pool, you should probably get out. That stuff can make anyone sick. Specifically, it’s the bacteria in fecal matter, like e. coli, that’s bad for you. The really bad news is, it is highly likely that there is some fecal matter and bacteria present in the last pool you last swam in. According to the Centers for Disease Control and Prevention, people have about 0.14 grams of feces on their bottoms, which likely dislodges in a swimming pool. Here’s where chlorine — that not-so-sweet-anymore smell — comes to the rescue, although the CDC says it could take up to a day to kill today’s stronger, more highly evolved germs. In the meantime, your exposure could possibly cause itchy hot-tub rash, or even respiratory illness.
Although all of this is revolting, in the grand scheme of pool life, there are far more important things to worry about: Drowning, diving into shallow water, running on the pool deck, and margaritas are all way more dangerous. So long as you’re not deliberately drinking the pool water, you’ll probably be okay. And if you are planning on drinking the pool water after reading this, you might want to consider professional help.
Questions or comments?
Give me a call or send me an email.
We would be happy to work with our Gateway neighbors and surrounding areas to help in any way possible.
Sincerely your neighborhood Pool Professional,
Advantage Pool Services, Inc.