LIFE'S LITTLE MYSTERIES: Has all the water on Earth been peed before? & Making wastewater drinkable is a growing trend as water resources become more strained 13JUN&11MAR26

Was your water once peed out by an animal?

(Image credit: Monica Murphy via Getty Images)

 HERE in Virginia, Maryland and D.C., depending on where you are, we are experiencing moderate, severe and extreme drought conditions for the second year running. It looks like 3/4ths of the country is experiencing some sort of drought per the U.S. Drought Monitor Map as of  9 JUNE 26. A lot of these areas have been experiencing drought for 3, 4, and 5+ years. Some cities are considering recycling their sewer water back into their drinking water systems. One American city has. That just gives a lot of people the heebie-geebies and they don't believe it can be done safely. The article from NPR (have you donated to NPR and PBS since drumpf/trump and the gop / greed over people-republican party controlled congress stopped federal funding for them?) is about how this is already happening in Altamonte Springs, Florida. And the article from Live Science discusses if all the water on Earth has been peed at least once or not.....

Has all the water on Earth been peed before?

Water, water, everywhere … has all of it been peed out at least once?

By Madeline Shaw

13 June 2026

As water molecules move around the planet through the water cycle, they take on many forms, moving from solid to liquid to gas and back again. They can make up snowpacks melting in the spring, a river rushing to the ocean, clouds carried on sea breezes, and even pee flushed down the toilet.

But with this complex cycle of evaporation, condensation and precipitation continuing over and over, has the water coming out of your faucet been inside a dinosaur or a mammoth at some point? And does that mean all the water on Earth has been peed before?

The answer depends on how you approach the question.

For Neil Donahue, director of the Steinbrenner Institute for Environmental Education and Research and a professor of chemistry and chemical engineering at Carnegie Mellon University, the answer should be "emphatically yes," based on a back-of-the-envelope calculation. But this math is based on a few assumptions, Donahue told Live Science over email.

The first is that the average person weighs about 110 pounds (50 kilograms) and pees about 0.26 gallons (1 liter) per day, which is roughly equivalent to 2.2 pounds (1 kg). Then, Donahue made a "WILD assumption" that all animals pee roughly the same proportion — 1% of their body weight — which he said is "probably wrong" but helpful for a ballpark estimate.

Next, if the total mass of all chordates (the taxonomic group that includes mammals, birds, fish,) is approximately 2.2 billion tons of water and carbon (2 billion metric tons), this equates to around 0.2 gigatonnes — or 80,000 Olympic-sized swimming pools — of pee every day, Donahue said. For the sake of the calculation, he assumed that the weight of chordates has remained constant over time.

Pee is one of many stages that make up the water cycle.

(Image credit: Vicki Jauron, Babylon and Beyond Photography via Getty Images)

On the water side of the equation, the U.S. Geological Survey estimates that Earth has about 1.4 billion gigatons of water, including that in oceans, ice caps, glaciers, lakes, rivers, groundwater and vapor.

If you divide the weight of the world's water by 0.2 gigatonnes of pee each day, it would take around 7 billion days, or about 19 million years, "to pee out the whole ocean," Donahue said. Given that the asteroid that "smacked the Yucatan" and wiped out the nonavian dinosaurs struck 66 million years ago, "even mammals have probably peed more than an ocean since we took over," he said.

David Kreamer, a professor of hydrology at the University of Nevada, Las Vegas, agreed that when "you go back in history to the dinosaurs and things like that, that's a lot of pee." But he also said calculations that depend on assumptions and generalizations have a large margin of error.

Instead, when it comes to whether every last drop of water on Earth has been peed at one time or another, Kreamer said the answer is no.

For one, water does not move through the water cycle at a constant speed, he noted; water can be trapped as glacial ice for hundreds of thousands of years, and "there is some deep groundwater that's been underground for tens of thousands of years."

What's more, some water hasn't ever been in the water cycle, he said. This water, known as juvenile water, is trapped deep below the planet's surface and "hasn't really emerged from the depths of the Earth ever in Earth's history," Kreamer told Live Science.

Over time, juvenile water can be brought to the surface through volcanic activity in the form of steam or lava. Trapped deep in Earth's crust, "it's released when magma dissolves it, and when a volcano blows up into the atmosphere," Kreamer explained, noting that during eruptions, "there's a certain amount of water or moisture that's released" alongside ash and rock. This water would then enter the water cycle and could eventually find its way into and out of an animal.

Ultimately, at any given time, at sites of volcanic activity around the world, there are streams of new water reaching the surface for the first time. That water "hasn't been peed," Kreamer said ‪—‬ at least, not yet.

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Making wastewater drinkable is a growing trend as water resources become more strained

March 11, 20263:57 PM ET

Heard on All Things Considered

From

By 

Molly Duerig

Making waste water drinkable is a growing technology trend, especially in areas where limited water resources are restricting development.

AILSA CHANG, HOST:

The country's water supply is coming under increasing strain. But as groundwater resources dwindle, another water supply strategy is gaining momentum. Molly Duerig with Central Florida Public Media in Orlando reports on the rise of recycled water, meaning recycled treated wastewater - that's right, for drinking.

(SOUNDBITE OF SPRINKLER SPRAYING)

MOLLY DUERIG, BYLINE: The idea of reusing treated wastewater is nothing new. Here in Florida, more than 300 million gallons a day gets used to irrigate people's lawns.

(SOUNDBITE OF WATER BUBBLING)

DUERIG: What's newer is an idea that's growing, and for some, much harder to digest - drinking treated wastewater.

FRANK MARTZ: It's really just recycled water.

DUERIG: That's Frank Martz, city manager at Altamonte Springs, just about 10 miles north of Orlando.

MARTZ: You know, 40 years ago, 30 years ago, 20 years ago, just the notion of taking stormwater and sewage and turning it into drinking water sounded ridiculous to many and scary to many.

DUERIG: And here at the city's pilot facility, I'm about to try some. There's no sink here, so Martz turns a knob on one of the pipes and out flows the water, clear and odorless.

(SOUNDBITE OF WATER SPLASHING)

DUERIG: It's water. I'm about to drink. Yeah, it tastes completely normal.

If you hadn't told me this was recycled wastewater, I wouldn't have known. Since I do know where this water ultimately comes from, drinking it still feels a little strange. But Martz plus many water engineers and scientists say it's perfectly safe.

MARTZ: It is chemically clean. It is biologically clean.

DUERIG: Florida is now one of four U.S. states where regulations allow for recycled wastewater to be treated and distributed for drinking, what's called direct potable reuse. The others are Arizona, California and Colorado, where similar pilot projects are underway. Bruno Pigott, a former senior official with the Environmental Protection Agency, now heads up the WateReuse Association, a trade group that lobbies for using what they call recycled water, including for drinking.

BRUNO PIGOTT: It's easy for me to say I'm excited about it. But I've got to make sure that the public is understanding it, that it's pure and safe, and understands the complex nature of water and that every drop of water's been used before.

DUERIG: Pigott says it's a challenge, but he's confident drinking treated wastewater will only keep growing in the U.S.

PIGOTT: It's spreading across the country.

DUERIG: And in Florida, rapid growth is driving the state to encourage it. There are skeptics, though, like Daytona Beach resident Greg Gimbert. He's been mobilizing people against direct potable reuse. Here's Gimbert speaking at a recent county council meeting.

(SOUNDBITE OF ARCHIVED RECORDING)

GREG GIMBERT: Today, you should put forward a version of our ban on toilet-to-tap.

DUERIG: Critics call it toilet-to-tap. In reality, this water goes through many steps of treatment after the toilet before people can drink it. Gimbert says he still doesn't trust the process and sees it as a ploy to allow for Florida's unlimited growth.

(SOUNDBITE OF ARCHIVED RECORDING)

GIMBERT: Maybe cut back on new development until you can cut over to a safe water supply.

DUERIG: Back in Altamonte Springs, Frank Martz says the technology here is the way of the future.

MARTZ: The water itself is ready. The question is, are the users ready?

DUERIG: Maybe not quite yet. These treatment plants are costly, and it will take a while for local utilities to build them.

For NPR News, I'm Molly Duerig in Orlando.

(SOUNDBITE OF MUSIC)

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