Is Toilet Water Clean?

If you were stranded on a desert island, what three things would you bring?

We’ve all played similar hypothetical questions games, flexing our brains to validate our choices. Here’s a good one for you: Would you drink toilet water? What if you were stranded, not on a desert island, but in your home after a natural disaster?

Sounds pretty gross, but desperate times call for desperate measures. It’s worth asking an expert: Is toilet water clean? Like, clean enough to drink? Let’s get to the bottom of this theoretical scenario with Tap Score water quality engineer Johnny Pujol.

Is Toilet Tank Water Clean?

No. It starts out clean, but that’s only before it actually hits the tank.

“The water destined for your toilet is coming from the same source as the water heading towards your tap,” Pujol says. “It’s the same water that comes out of your sink.”

After that, things get murky. For one thing, Pujol says, “It is likely that your toilet tank is very rarely cleaned.”

Be honest: When was the last time you drained and scrubbed the inside of your toilet tank? If that answer is never (raises hand), the tank’s probably not pristine. After all, it is in the bathroom.

“[B]ecause of this,” Pujol says, “the water in the tank could be contaminated, and it would then contaminate any clean water entering the tank.” Once the clean water meets the dirty tank, it’s game over.

As far as the bowl goes, come on now. You know the answer to this one: “Because the toilet bowl is exposed to feces,” Pujol says, “there are likely bacteria living in and around your toilet bowl that can contaminate the water.”

So the water from the pipe to the tank is (theoretically) clean, but the bowl water is definitely not. Even clean freaks who scrub the toilet bowl every day will miss something.

Is Toilet Water Safe To Drink?

It depends, but let’s make one thing clear: “[W]e don’t recommend drinking water from your toilet tank or bowl if it can be avoided,” Pujol says.

If? Is that a caveat I see? Let’s say you were desperate — natural disaster, zombie apocalypse — and there was no potable water. That toilet tank would look pretty good. Could you make it work?

Well, sure. But you’d definitely have to treat it. “If you treated your toilet tank or bowl water with the intent to drink it,” Pujol says, “you’d want to focus on disinfection for bacteria.”

Water purifiers could theoretically clean toilet water, if you really were dying of thirst. We’re not talking about a regular Brita, though. Find one that works on bacteria.

Safe Uses for Toilet Water

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Safe uses for toilet water include:

• Flushing toilets;
• That’s it.

Seriously, folks: There are just not that many things you can do with toilet water. At least not in your home.

After it leaves your house? That’s a different story. Once flushed, toilet water heads to the wastewater treatment plant, where it’s cleaned and released into our rivers and streams or diverted to farms for irrigation.

Pujol says it probably wouldn’t hurt anything if you watered your plants with toilet water, but why would you want to?

What If My Dog Drinks Toilet Water?

It’s generally OK. But Pujol says it depends on how long the water has been in the bowl, and if the bowl is clean.

Dogs have different digestive systems than we do, and they’re typically more resistant to bacterial infections. Dogs eat trash, roadkill and random chicken bones on the sidewalk, so a little toilet water is unlikely to do much harm.

“Even if the toilet bowl is contaminated,” Pujol adds, “your dog might not get sick because it takes exposure to a pathogenic strain at a high enough concentration to cause illness.”

If you’re worried or don’t want a slobbery mess, keep the toilet lid down. “We still can’t recommend giving your dog toilet bowl water on purpose,” Pujol says. “But if it happens, it’s not guaranteed to be an issue.”