Who’s Climbing Into New York’s Sewers at Night — and Why?

New York is a city that has already seen just about everything.

But even in a city that never stops surprising people, this phenomenon has raised plenty of questions:  In recent weeks, unusual videos have been spreading across social media, showing groups of people arriving late at night at city sewer manholes, removing the heavy iron covers, and descending into the underground tunnel system. 

When do they come back out? According to security cameras that captured the whole thing, the groups stay down there for long hours and only return to the street near dawn. 

In one video, seven people can be seen emerging one after another from a manhole in the middle of an intersection in Williamsburg. Some wore headlamps and carried gear that looked like tools, but a police investigation has so far produced no significant results — and the public is concerned, understandably so. 

Who are these people, and what are they doing beneath the feet of millions of sleeping Americans while no one is watching? Even more troubling is the fact that the incidents were documented in several different locations, in Brooklyn and Queens.

Treasure Hunters — or Something Else?

Another video shows people dressed in tall boots and special suits as they climb down into a manhole in Queens and close the cover behind them. After the videos went viral, the New York Police Department (NYPD) stepped in, and a special rescue unit, together with staff from the city’s Department of Environmental Protection, began trying to solve the mystery. 

The teams went down into the sewer systems themselves to check whether any hazardous materials, suspicious equipment, or signs of criminal or terrorist activity had been left behind. 

According to the authorities, no damage to the sewer system has been found so far, and no threats to the public have been identified. No arrests have been made either. So what are they looking for down there? That’s where the story becomes truly mysterious, because despite the investigation, no one knows for certain what the purpose of these descents into the underground system was.

One theory investigators are considering is that these are urban treasure hunters. According to that assessment, some people enter the sewer system searching for coins, jewelry, wallets, and valuable items that were lost over the years and washed into the drainage system. As much as the story sounds like something out of a movie, it turns out there is precedent for it.

For decades, stories have circulated in New York about people entering the city’s tunnels in search of lost treasure. In the past, people have even been arrested after being caught searching for gold, coins, and weapons in underground systems. Some experts believe the recent incidents are connected to the culture of “urban exploration” — a hobby in which people investigate closed-off, abandoned, or otherwise inaccessible places, including tunnels, old train stations, and sewer systems.

Why Is It So Dangerous?

Even if these are just curious adventurers, authorities stress that entering the sewer system is prohibited and extremely dangerous. Beneath New York’s streets stretches a vast network of more than 12,000 kilometers of pipes and tunnels. In many places there are toxic gases, the danger of sudden flooding, electrical wires, and conditions that can be life-threatening.

Police officials compared the risk to walking in the middle of a highway and warned that even experienced people can get hurt.

And what do residents think? On social media, countless theories have already surfaced. Some claim they’re treasure hunters, others are convinced they’re tunnel explorers. And of course, some haven’t given up their sense of humor and have compared the mysterious figures to various familiar characters from the world of superheroes. 

Police are continuing to investigate the cases, and the whole city is waiting for an answer to the simple question: What exactly are these people searching for deep beneath the streets of New York?