Sewers and drainage systems play a far more essential role in modern society than many realize. In the past, before sanitation systems became widespread, human waste and other refuse were often simply discarded from windows or tossed onto the streets—sometimes even landing on the heads of unsuspecting pedestrians below.
Today, with the push of a button or a pull of a lever, we rarely consider where our waste ends up. While sewers are efficient at handling waste, they also tend to collect some rather surprising objects. Here are 10 of the strangest things ever found in these underground channels.
10. A Rave

What could be more thrilling than gathering for a late-night dance at a secret spot and letting loose?
How about doing it in a sewer!
Once they arrived, the partygoers discovered a full light-and-sound setup, and the celebration kicked off. But by around 4:00 AM, one of the revelers began to feel the oppressive atmosphere of the underground space. Concerned for everyone's safety, they contacted the authorities.
When the police arrived, they shut down the event, allowing the attendees to leave with a stern warning about the hazards of combining alcohol with the risks of confined, easily flooded tunnels.
9. Fatberg

When we flush unpleasant things away, we hope they vanish without a trace. For sewer workers, though, our discarded items can create real-life monsters.
The 2017 London fatberg was an enormous, decaying mass stretching over 250 meters (820 feet). In the city's sewers, disposable items like diapers, wet wipes, and condoms had become entangled in congealing fats, creating a clog that could have blocked the sewer and caused raw sewage to flood the streets above.
Weighing as much as 19 African elephants, the fatberg was dismantled by sewer workers using spades and high-pressure water jets. However, for some, the fatberg represented more than just an example of human wastefulness—it was a historical treasure.
The Museum of London acquired a piece of the fatberg for future generations. To ensure its preservation, curators had to X-ray it for hidden hypodermic needles and wear biohazard suits. Eventually, a portion of the mass was stabilized (to prevent further decay or fly hatching) and became a centerpiece of the museum's fatberg exhibit.
8. An Alligator

One of New York's most famous urban legends is that the city's sewer system is teeming with alligators. According to the story, people would buy baby alligators, only to realize that hissing reptiles with sharp teeth don't make great pets. As a result, they'd flush the gators down the toilet.
The legend suggests that in the sewers, these alligators now roam and thrive. However, there is no solid evidence of an alligator colony in the city's sewers, and most experts agree that the temperature is too cold for the animals to survive for long. Interestingly, in 1935, a 2.4-meter (8-foot) alligator was discovered in East Harlem, emerging from a manhole, but how it ended up there remains a mystery.
In areas where gators are more at home, it's not so strange for them to appear in sewers and drains. So if you peer into a drain and spot a pair of cold, relentless eyes staring back, it might not be Pennywise preparing to strike.
In Florida, alligators often end up being pulled out of sewers after getting swept in by rainstorms or chasing after prey that ends up in the drains. In Louisiana, a 3-meter (10-foot) alligator was seen waddling out of a storm drain and then settling down for a nap on a suburban porch.
7. A Cow

Not all creatures found in drains are as dangerous. When a dead cow was discovered in a sewer in Britain, it was fairly tame. However, there have been reports of live cows being found underground.
In Fujian Province, China, a farmer spent four days searching for a missing cow. Just as the farmer was about to give up, a strange mooing sound was heard coming from beneath the village.
A manhole cover was removed, and the missing cow's head appeared from the depths. A makeshift winch was then used to lift the cow back into the fresh air, seemingly no worse for the wear after its underground escapade. However, the mystery of how it ended up in the sewer remained unsolved.
In India, where cows are deeply revered by Hindus, a calf was seen slipping into an open sewer, carried away by the current. Witnessing this, a man climbed into the sewage and dove in to rescue the animal. Both the cow and the man emerged unharmed, if not exactly fresh-smelling.
6. A Sewer Monster

In 2009, a video showing an unexplained and supposedly alien creature in a North Carolina sewer went viral. The footage depicted a pulsating, wriggling pink mass clinging to the sewer wall. Were the aliens done exploring human orifices and now targeting our drainage systems?
Not exactly.
Experts quickly identified the creature as a group of Tubifex worms. These common segmented worms are typically found in moist soils.
The apparent pulsing motion of the so-called 'monster' was likely caused by the camera’s light, which may have been overly hot. While these worms are not rare, it is unusual for them to appear in a sewer. This is why even experienced workers were initially unable to recognize this fascinating, albeit repulsive, congregation of worms.
5. A Baby

When a woman in China heard a baby crying from a drain beneath a toilet, she immediately raised the alarm. Rescue services soon arrived, and after two hours of effort, they successfully extracted the baby—alive—from the pipe it had become stuck in.
The police began searching for the baby's mother. Soon, they realized that the woman who had initially called for help was the person they had been looking for. In labor in the toilet, she had unexpectedly delivered her baby and watched it slip down the drain.
Her story was a tragic one. The child's father had refused to provide support, and she was overwhelmed with uncertainty about raising the baby on her own. This caused her to panic when the baby began to arrive.
In a case from South Africa, a baby estimated to be between one and three days old was discovered in a storm drain after passersby heard her cries. Over the course of four hours, drills and chisels were used to break into the drain and rescue the child. The baby was in relatively good health and was named Sibanisethu ('Our Ray of Light') by the locals.
4. A Community

Las Vegas is a city known for extremes, not just in terms of gambling. When it's dry and hot, it’s unbearably dry and hot, but when it rains, the storms can be torrential. To prevent the city from flooding, 1,600 kilometers (1,000 miles) of storm drains were built to direct rainwater away from the streets.
Soon, other residents began to inhabit the tunnels. Homeless individuals, excluded from the sparkle and extravagance of the Strip above, made the drains their home, and thus, the tunnel people of Las Vegas came into existence.
The narrow tunnels of Las Vegas are home to scorpions, graffiti, and people struggling through tough times. During rainfall, the tunnel dwellers face the risk of losing everything they own, including their lives, to the rising floodwaters. While no one knows the exact number of people living beneath the city, it’s believed to be in the hundreds.
Some tunnel residents manage to hold down menial jobs, returning to the tunnels only to sleep. Others, however, spend the majority of their time in the dimly lit underground passages beneath the neon lights of the city.
3. Snakes

Humans are at their most vulnerable when sitting on the toilet. Just as you settle in, the phone rings, the doorbell rings, or a snake strikes your backside.
Yes, there are places where encountering a snake in your toilet is a common occurrence. In Australia, a woman startled a carpet python in her toilet, leaving several puncture marks on her backside.
The snake might have sought refuge in the toilet to escape a heatwave, but there are numerous reports of snakes emerging from sewers through toilets. Often, they are following rats who have used the toilet as an escape route into homes. Once in the toilet, the snake may find it a cozy resting place—until someone sits down.
Don’t assume it’s only in the infamous Land Down Under where you might get bitten in an awkward spot. Snake sightings in toilets have been reported everywhere from Texas to Seattle, South Africa to Southend in the UK. Perhaps it’s worth checking under the seat the next time you answer nature’s call.
2. Drugs

Anything that passes through the human body eventually makes its way into the sewer system, and drugs are no exception. In fact, they can create significant issues. For example, contraceptive pills contain hormones that regulate women’s reproductive cycles. However, when these hormones end up in rivers and waterways, they can lead to disturbing changes in freshwater fish, affecting their reproductive abilities and potentially causing population declines.
One method of monitoring recreational drug use involves examining the contents of sewers. By analyzing the waste collected at sewage treatment plants, researchers have found that drug consumption is far more widespread than commonly believed. For example, one study found spikes in the use of marijuana, cocaine, and methamphetamine during periods of celebration.
Sometimes, it’s not only drug waste that surfaces in the sewers. In Palermo, police discovered 77 marijuana plants thriving in the city’s sewer system.
1. Gold

While it’s not common to find anything worth recovering in a sewer, aside from the occasional accident where something valuable is flushed away, there may be millions of dollars in precious metals being washed down each year.
Researchers have estimated that nearly $2 million worth of gold, along with an equal value of silver, pass through Switzerland’s sewers annually. This is largely due to the tiny metal flakes that are lost in the jewelry and watchmaking industries. In areas where gold is worked on a large scale, it might just be worth sifting through quite a bit of waste in search of a glittering find.
In Suwa, Japan, a town aptly named for its gold extraction efforts, gold has already been recovered from sewers. By burning the waste sludge left after sewage treatment, they discovered that the remaining ash contained 2 kilograms (4.4 lb) of gold for every ton—a richer source than even some gold mines provide.
