Work is under way on ‘spring cleaning’ the ageing Victorian water mains network under the streets of London.

Contractors have been brought in by Thames Water to spruce-up the brick-lined tunnels by clearing out sand and silt and check any damage.

They also do repairs where needed in the transfer ducts that carry untreated water from reservoirs and rivers to waterworks to be processed before being pumped into the mains.

“Inspecting the tunnels is a risky job,” explained Thames Water’s Jason Aldred. “We need to isolate the tunnel so there is no water coming in.

“We never know what we’re going to find till we get down there. It can take up to three weeks on each repair, working in tunnels anything from 5ft in diameter to 7ft.

“Sometimes the nearest exit is two miles away—so it’s not a job for the faint-hearted.”

It takes elbow Greece, Thames Water has found, to shift the gunk that builds up over time.

“There is nothing as effective as a shovel and wheelbarrow,” Jason added. “It may sound basic, but it’s the best way to get them cleaned down and checked.”

Contractors have so far inspected eight miles and have also gone through the main tunnel carrying water across east London between the Walthamstow reservoirs and the New River, ready to start cleaning up.

[Picture: Charlotte Snowden]