We’ve all used them. Whether at festivals, campgrounds, construction sites, or even weddings, porta potties are an unavoidable—and often underappreciated—part of modern life. They’re the unsung heroes of moments when bathrooms are few and far between, faithfully answering nature’s call, one flushless visit at a time.
But how do porta potties work, exactly? They’re so commonplace—and so universally dreaded—that most people try to get in, do their business, and get out as quickly as possible, without giving much thought to what’s happening. But plug your nose, lift the lid, and brave a peek inside, and you’ll find a simple yet elegant system designed to reliably meet one of humanity’s most basic needs.
How do toilets work?
Conventional toilets rely on a combination of water, pressure, and gravity to do their job. When you flush, water rushes from the tank into the bowl, pushing waste down through a curved pipe called a trap and into the plumbing system.
From there, the wastewater travels through sewer pipes to a treatment plant or, in some instances, a septic system. A small amount of water remains behind in the trap, creating a seal that prevents sewer gases from wafting back into the bathroom.
Once the process is complete, the tank refills with clean water from the plumbing system, typically from a municipal water supply or private well, and the porcelain throne is ready for its next user.
How porta potties work differently
Portable toilets—also known as portaloos, portajohns, and a variety of other nicknames—use water, too. But that’s about where the similarities end. “There’s no plumbing, and it really doesn’t smell good,” says Walt Terry, director of operations for Metro Services, a family-owned portable toilet and dumpster rental company in Little Rock, Arkansas. “It’s not the most pleasant thing in the world.”
Modern porta potties come in a variety of shapes and sizes, from swanky multi-stall trailers to no-frills cubicles. The standard plastic model you see at events has a relatively simple design, one that traces its roots to George Hardig. Hardig filed a late-1960s patent for porta potties. Later he became a co-founder of PolyJohn Enterprises, still one of the leading portable toilet manufacturers today.
Made of large, rigid plastic panels, Hardig’s invention was designed to be weather- and insect-proof, simple to clean and maintain, and lightweight and easy to move. His model was cylindrical and featured a removable toilet tank, while today’s are usually rectangular and have the holding tank built-in. But other than that, not much has changed in porta potty design since Hardig first developed his portable toilet “cabana” nearly six decades ago.
Porta potties are designed to be easy to move. Image: Suiren2022 / CC BY-SA 4.0
These tall boxes have a large empty cavity at the back, topped by a toilet seat. When users do their business, waste simply drops down into the large, roomy hole beneath.
“It’s just a big void space,” says Katie Gossett, office manager for Tidy Tim’s, Inc., a portable restroom and septic service company her dad started more than 30 years ago in central Ohio.
“The holding tanks can vary a bit in size, but your average is like 25 to 30 gallons.”
What’s that blue liquid in porta potties?
The holding tank is filled with some amount of water, typically between five and 10 gallons, as well as a special, dark-blue chemical cocktail that serves numerous purposes. It helps keep the funky odors under control and starts to break down the waste and toilet paper, while also hiding the tank’s contents. The color is also a key indicator of a porta potty’s freshness.
“It will actually turn green once it’s not working anymore—when it gets there, it’s not a good sight,” says Terry. “The chemical goes in there and does as much as it can, until it can’t.”
Porta potties need ventilation
There’s another easily overlooked component that helps keep porta potties from getting too stinky: the vent pipe. The next time you use a portable toilet, look up at the roof. You’ll spot a small pipe protruding from the back corner, discreetly drawing foul gases out of the holding tank and venting them into the air.
Some models also have built-in urinals, which simply funnel urine into the holding tank for those who prefer to remain standing when they pee.
How porta potties get cleaned
When it’s time to service a porta potty, specially trained employees from the rental company arrive with a powerful vacuum truck. They use a hose to suck out the tank’s liquids and solids, transferring the waste into the truck for disposal.
Many vacuum trucks also have a separate compartment filled with clean water, which staffers then use to wash out the porta potty’s entire interior—the tank, as well as the walls, ceiling, and floors.
Sanitizing spray and a quick wipedown with a microfiber towel finishes the job—which is a lot less gross than you might imagine. “Our guys know what they’re doing,” says Gossett. “I’m not going to say accidents don’t happen, but most of the time, when they get [back to the office], they are exactly the way they left. They very rarely get dirty.”
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How often are porta potties cleaned?
Rental companies typically service their units on a regular schedule, going around to the various porta potties they own and sucking out all the waste. Once the vacuum truck is full, they drive to a local wastewater treatment facility and dump it.
“It’s like a city sewer plant that is able to add some to their load,” says Gossett. “Their treatment plant is big enough that they can take on that extra waste and process it for us.”
The servicing schedule varies, but a good rule of thumb is that one portable restroom can accommodate 10 people during a typical 40-hour workweek before it needs to be cleaned out.
And, no, unless you go totally crazy, your porta potty probably isn’t going to overflow.
“A lot of people worry that they’re going to fill up, but usually that’s not the case,” says Kade Jensen, the owner of Minty Pine Sanitation Solutions Ltd. in southern Alberta, Canada.
Porta potties are kind of going viral
Porta potties have gotten a bad rap over the years. Yet there’s an entire corner of the internet that’s apparently fascinated by what happens when they get cleaned out.
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A post shared by Minty Pine Cleans (@mintypinecleans)
Jensen, who is 23, found that out a few months ago, when he started posting regular point-of-view videos of his porta potty cleanouts on social media. Each one starts with a direct look into the full tank, but ends with the oddly satisfying payoff of a squeaky-clean unit.
Since then, he’s watched his company’s follower count skyrocket, and his views climb into the hundreds of millions. “A lot of people have always seen [porta potties] and used them, but they don’t know the exact process,” he says.
“It’s almost like people want to look away but they can’t look away at the same time. It’s something you’re not used to seeing.”
When he first started posting videos, Jensen says, he was simply having fun. But the response has given him a new perspective: He now sees the videos as a way to pull back the curtain on an industry that most people would rather not think about—and show that portable restrooms aren’t nearly as revolting as their reputation suggests.
“Our whole thing is that it really doesn’t have to be gross,” he says. “It’s really not as scary or gross as people make it out to be.”
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