Sewers and drains are more vital to civilization than many people in the modern world realize. Before the advent of widespread sanitation, waste and grime were often hurled out of windows onto streets—or even onto the heads of unsuspecting passersby.
Today we simply press a lever and never really think about where our unwanted leftovers travel. Yet these underground arteries collect far more than just sewage, often swallowing the odd and unexpected. Below are the 10 strangest things ever uncovered beneath our feet.
10 Strangest Things Found in Sewers
10 A Rave
Imagine a midnight rave hidden in a concrete tunnel—who could resist the allure of dancing under the city’s veins?
Now picture that party taking place inside a sewer!
Back in 2017, more than two hundred thrill‑seekers in Newcastle, England, waded through grimy water to discover a dry alcove within the storm‑drain that feeds the River Ouseburn. The gathering was coordinated on Facebook, with participants meeting at a local pub before plunging into the underground channel.
Inside, they found a full‑blown light and sound rig already set up, and the festivities kicked off. At around 4 a.m., one reveler began to feel the cramped, damp environment getting too oppressive. Concerned for everyone’s safety, they dialed the police.
Authorities arrived, shut down the impromptu concert, and escorted the crowd out, issuing a stern reminder about the hazards of mixing alcohol with confined, flood‑prone tunnels.
9 Fatberg
When we flush away the unsavory bits of daily life, we hope they’ll never resurface to haunt us. For the brave souls who maintain our underground networks, however, our careless disposals can combine into true monsters.
The 2017 London fatberg stretched over 250 metres (820 ft) and resembled a rotting, congealed serpent. Inside the city’s sewers, stubborn items such as diapers, wet wipes and condoms tangled with solidifying fats, creating a blockage that threatened to spill raw sewage onto the streets above.
Weighing as much as nineteen African elephants, the beast was finally broken apart by workers wielding spades and high‑pressure water jets. Yet the fatberg proved more than a nuisance; it became a piece of urban history.
The Museum of London managed to acquire a chunk for posterity. Curators had to X‑ray the greasy mass for hidden hypodermic needles and don bio‑hazard gear. After stabilising the sample to halt decay and fly‑hatching, it now stars in the museum’s dedicated fatberg display.
8 An Alligator
One of New York’s most persistent urban legends claims that the city’s sewers are teeming with alligators. Supposedly, people bought baby gators as novelty pets, soon discovered they’re terrible companions, and flushed them down the toilet.
Folks say the reptiles now prowl the underground waterways. In reality, there’s no solid evidence of a thriving alligator colony beneath Manhattan, and experts agree the climate is far too cold for long‑term survival. Nonetheless, a 2.4‑metre (8‑ft) alligator was recovered from an East Harlem manhole in 1935, leaving the mystery of its arrival unsolved.
In regions where alligators naturally belong, sightings in drains are less odd. If you peer into a dark pipe and glimpse gleaming eyes, it might be a gator, not a mythic monster.
In Florida, rain‑driven floods have forced alligators into storm drains, where they are later hooked out. In Louisiana, a 3‑metre (10‑ft) alligator was spotted waddling out of a drain before taking a nap on a suburban porch.
7 A Cow
Not every subterranean visitor is a fearsome predator. When a bovine was discovered in a British sewer, it was already deceased and rather placid, yet live cows have been found underground as well.
In China’s Fujian Province, a farmer searched for a missing cow for four days. Just as hope waned, a strange moo echoed from beneath the village. Lifting a manhole cover revealed the bewildered animal poking its head out. Villagers rigged a makeshift winch and hauled the cow to the surface, where it emerged unharmed, though its underground escapade remained a mystery.
Across the world in India, a calf slipped into an open sewer and was carried away by the flow. A brave passerby dove into the foul water to rescue the youngster. Both animal and rescuer survived, albeit with a lingering scent of sewage.
6 A Sewer Monster
In 2009, a video purported to show an alien‑like monster pulsating on a North Carolina sewer wall went viral. The eerie pink mass seemed to pulse and writhe, sparking wild speculation about extraterrestrials targeting our drainage systems.
Scientists quickly identified the source: a dense colony of Tubifex worms, common segmented worms that thrive in moist soils. The apparent throbbing was likely caused by the camera’s hot light, which can make the worms’ bodies contract rhythmically.
While the worms themselves are ordinary, their sudden appearance in a sewer was unexpected, baffling even seasoned workers who had never seen such a gathering of these slimy creatures.
5 A Baby
In China, a frantic woman heard a baby’s cries emanating from a drain beneath a toilet. She called emergency services, and rescuers spent two harrowing hours extracting the infant—still alive—from the pipe where it had become wedged.
Police soon realised the woman who raised the alarm was also the mother. Overcome with labor while using the toilet, she delivered the child herself, only to watch the newborn slip down the sewer line.
The tragedy stemmed from an absent father who refused to support the baby, leaving the mother to face the ordeal alone. A similar incident occurred in South Africa, where a newborn, aged between one and three days, was found screaming in a storm drain. After four grueling hours of drilling and chiselling, rescuers pulled the child out, and she was later named Sibanisethu—“Our Ray of Light”—by the local community.
4 A Community
Las Vegas is a city of extremes, famed for its neon lights and relentless gambling. When the desert climate is bone‑dry, the city is parched; when rain arrives, torrents can flood the streets.
To combat flooding, the municipality built roughly 1,600 kilometres (1,000 mi) of storm‑drain tunnels to channel rainwater away. Over time, these conduits began to serve another purpose: shelter for the city’s homeless population, giving rise to the “tunnel people” of Las Vegas.
The cramped, dimly lit passages are home to scorpions, graffiti, and those down on their luck. When heavy rain strikes, the tunnel dwellers risk losing everything—including their lives—to sudden floodwaters. Estimates suggest hundreds of people may be living beneath the Strip, though the exact number remains unknown.
Some tunnel residents hold low‑wage jobs and retreat to the sewers only to sleep, while others spend most of their days in the shadowy corridors, forming a hidden community beneath the city’s glittering façade.
3 Gold
Beyond the occasional accidental loss of valuables, sewers might actually be a hidden treasure trove. Scientists estimate that nearly $2 million worth of gold—and a similar amount of silver—flows through Switzerland’s sewage system each year.
Much of this precious metal likely originates from tiny flakes shed by the country’s renowned jewelry and watchmaking industries. In locales dense with goldsmiths, sifting through sludge could yield more glimmer than a traditional mine.
In Japan’s Suwa, researchers have already extracted gold from sewage sludge. By incinerating the waste, they produced ash containing roughly 2 kilograms (4.4 lb) of gold per ton—an ore grade richer than many conventional gold mines.
2 Drugs
Everything that passes through a human body eventually finds its way into the sewer network, and that includes pharmaceuticals and illicit substances. These chemicals can cause serious environmental issues. For instance, contraceptive hormones from birth‑control pills enter waterways, disrupting fish reproduction and leading to population declines.
Researchers also analyse sewage to gauge community drug use. By testing wastewater at treatment plants, scientists have uncovered patterns showing spikes in marijuana, cocaine, and methamphetamine consumption during festivals and holidays.
Occasionally, the sewers hide more than just waste. In Palermo, police uncovered 77 thriving marijuana plants growing clandestinely beneath the city’s underground tunnels.
1 Snakes
Few moments are as vulnerable as when we’re perched on the toilet. In that brief pause, the phone may ring, the doorbell may buzz, or—if you’re unlucky—a snake might decide to bite you right where you’re sitting.
Snakes turning up in toilets is a genuine phenomenon. In Australia, a woman startled a carpet python that had slipped into her bathroom, earning her several puncture marks on her backside.
These reptiles often infiltrate homes by following rats that use sewers as escape routes. Once inside the bowl, a snake may linger, treating the porcelain throne as a temporary hideout until an unsuspecting occupant arrives.
The menace isn’t confined to the Land Down Under. Reports of snakes emerging from toilets have surfaced across the globe—from Texas to Seattle, South Africa to the UK’s Southend. So next time nature calls, you might want to glance under the seat before you sit.