A team of “sewer heroes” are destroying a 100-metre “concreteberg” beneath the streets of Islington – and they’ve been at it for three weeks.
Four Thames Water workers are down the 4ft 6in high and 2ft 6in wide hole under Goswell Road and Hall Street, with four more at pavement level.
One goes at the blockage with a pneumatic drill, another shovels rubble into a bucket, and the others run buckets toward the manhole on a bogie trolley, before its emptied into a "one tonne bag".
James O'Donoghue, fields operation manager, told the Gazette: "We have a family of rats down there enjoying our company. Every day they are getting closer and closer.
"I was the shoveller last week. It's really tough concrete. We started with a hammer and chisel and realised we weren't going to move it , so now we're using a pneumatic drill."
The bags are hoisted up by a crane, before being weighed and taken to the depot.
The team estimate they've cleared 25 bags in three weeks. One weighed in front of the Gazette came in at 784kg.
The drilling is the hardest job and a foghorn blares every 20 minutes, indicating it's time to swap. Each worker does two shifts on the drill a day, while those shovelling or running the buckets can expect to be in the sewer for 80 minute stints. One person on the pavement is constantly monitoring the decibel readings from the drill.
"There is soap discharged into this one," James said, "It's the cleanest sewer I have smelt: there must be a laundrette around here - but people's waste is coming in while we are down there."
James said one colleague got soaked with the contents of a flushed toilet. But they deal with such hazards on a daily basis.
"It's hot and stuffy," added Martin Codling. "It's about 27 degrees down there, even when the temperature was hot up here, it felt like a breath of fresh air. It can be scary. It's claustrophobic. It's pitch black."
This isn't a typical job for James and the team. But they care about their Victorian sewer systems so much they actively lobbied for the job over a third party contractor. One supervisor is said to have a London cab driver's knowledge of the city's sewer system.
"This is the most fascinating job I've ever had," said James. "It's like another city under the streets of London. I love it, the guys love it. There's camaraderie and it's a job to be proud of."
Thames Water found the "concreteberg", which bosses claim is the biggest they've ever encountered, in April.
It's blocking three sewers and an investigation into how it got there is ongoing.
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