NEW YORK (AP) 鈥� It wasn鈥檛 the rats. Or the smells. Or the germs.
No, the most unpleasant part of descending into New York City’s vast sewer system, according to former urban explorer Steve Duncan, was the cockroaches.
鈥淭hey鈥檙e all over the place, crawling on walls, dropping down on you,鈥� Duncan recalled this week. 鈥淭hey were the worst.鈥�
Duncan, 48, who now lives in Maryland, reflected on his years documenting the muck-filled tunnels running under New York after captured small groups of people mysteriously entering and exiting the sewer system in Brooklyn and Queens in recent days.
Police say they鈥檙e still investigating the three incidents but don鈥檛 believe there鈥檚 any threat to the public. Officials stress that it is both illegal and dangerous to enter the city鈥檚 (12,000 kilometers) of sewer pipes.
Duncan believes the groups were likely explorers like him, traversing the large, 19th century sewer mains that run underneath parts of the city.
These relatively cavernous spaces can exceed 6 feet (1.8 meters) in diameter 鈥� tall enough for most people to comfortably walk upright 鈥� and can feature handmade bricks and elegant arches, he said.
A number, including one near where one of the groups was spotted, trace the paths of naturally occurring waterways that once sustained New York, before industrialization fouled them and forced city builders to convert them to sewers, Duncan said.
鈥淭hese old streams, they get put underground as cities grow up around them,鈥� he explained. 鈥淚t鈥檚 amazing how much this old natural environment is part of the city today.鈥�
Going underground requires planning
The videos suggest that some of the groups spent up to three hours underground, a length of time that may seem unimaginable, but Duncan said passes quickly as sewer journeys require navigating slippery, humid environments and flowing water that could be a foot (30 centimeters) or deeper in places.
Duncan credits the groups with picking an optimal time for their excursions.
Heavy rainfall days earlier would have mostly cleared the system, and venturing into the tunnels in the early morning hours would mean waste flow would be noticeably less than during peak daytime hours.
鈥淭hey did their research,鈥� Duncan said.
But invisible dangers lurk in these pathogen-rich environments, he said, recounting how he’d landed in the hospital with badly infected extremities on two separate occasions, which eventually pushed him to retire.
Seasoned explorers will generally bring gas meters to check for dangerous levels of fumes, including potentially flammable hydrogen sulfide, which is produced by decomposition, Duncan said.
As to the smell of all that effluent, it鈥檚 not as overpowering as you鈥檇 think, Duncan said.
鈥淚f it鈥檚 a well-functioning sewer, it鈥檚 more like a barnyard, or compost pile smell,鈥� he said. 鈥淏ut when it鈥檚 bad, it can smell like death.鈥�
Subterranean explorers’ motivation raises questions
Some residents have worried the mysterious explorers captured on video were up to something nefarious. Many were dressed in waterproof hip waders and equipped with headlamps and what appeared to be shovels and other tools.
鈥淪ewers can serve as entry or exit points to buildings, and we have all seen movies in which criminals escape jail through a sewer,鈥� offered Magued Iskander, an engineering professor at New York University. 鈥淭here must be a reason beyond mere thrill to enter a dirty place like a sewer.鈥�
Others have noted that police have nabbed underground treasure seekers from time to time.
Three men were charged just last year with burglary and other counts after they went searching for gold, jewelry and other valuables in a Brooklyn sewer. A decade earlier, police caught three others as they , including a worker with the city Department of Environmental Protection, which manages the sewer system.
If anything, the viral videos underscore just how vulnerable some of the city鈥檚 vital infrastructure is, said David Sarni, a retired New York Police Department detective and professor at the John Jay College of Criminal Justice in Manhattan.
鈥淚s this something that could be exploited by people who look to do harm?鈥� he said. 鈥淵ou have to really take nothing for granted and always think, unfortunately, on that negative side.鈥�
Duncan, who now works in real estate, said neither riches nor malice motivated him and many others of his generation of urban explorers.
On his trips into underground passages in New York, London, Paris and elsewhere during the early 2000s, he rarely found anything of value, save for the odd credit card or tattered wallet.
鈥淭hese are terrifying places that take a lot of planning and dedication to explore safely,鈥� Duncan said. 鈥淵ou don鈥檛 do all of these things for the tiny chance of finding a diamond earring.鈥�
鈥淭he real reason is to see something new, or experience the city in a different way,鈥� he continued. 鈥淭hat鈥檚 the real lure.鈥�
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Associated Press video journalist Joseph Frederick in New York contributed to this story.
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