New clues over massive Surrey sinkhole after network of tunnels discovered near street

Independent

2 days ago

Months after a massive sinkhole sparked a major incident in Surrey, a network of underground Victorian tunnels have been discovered close to the site.
Residents of quiet Surrey village of Godstone were told to 'get out as quickly as possible' after a huge crater swallowed a street overnight on February 17.
More than 30 homes were evacuated as the sinkhole grew to up 19 metres in length, before a second one opened up days later.
Engineers working to repair the hole have now confirmed the discovery of abandoned sand mining tunnels around the site, which may 'provide a clue' into what caused the havoc.
Lloyd Allen, infrastructure manager at Surrey County Council, told the BBC: "Currently, we're investigating the Victorian tunnels, plotting them to see the extent of them and where they go.
"We'll likely be finished by the early part of December, but there's a lot of reconnecting services and redoing water mains, gas mains and electric cables."
He told the broadcaster that the discovery of the eight-metre deep tunnels "puts one of the pieces into place' over why the hole opened up, but added there were 'several scenarios that could have happened that led to this collapse".
In February, an expert suggested the incident could be related to the collapse of a nearby abandoned sand mine.
Andrew Farrant, the British Geological Survey (BGS) regional geologist for southeast England, said how old maps of the area, published in 1872, appeared to show an entrance to a sand mine very close to the crater.
'It is possible other unrecorded sand mines occurred in this area,' Farrant said. 'It is also possible that a leaking pipe has weakened the rock and led to the failure of a putative mine, assuming it exists and extended under the road. Equally, it is possible that gradual failure of a mine roof caused the water main to fail, triggering further subsidence.'
While engineers say they hope the repairs to be finished by December, local businesses told the BBC they have been 'left in the dark' over the repair plans.
One businesses owner said his income had been slashed to a third of what it once was due to the sinkhole.
"They said they would keep us up to date, but this hasn't happened," Shane Fry, who runs DD Services, a garage on the high street said.
"We need to know. It will benefit everyone in the area."
Will McLean, the owner of a residential windows and doors company described how the sinkhole had 'reduced footfall to virtually zero'.
"Financially it has been massive,' he said."In terms of business, we are down 60% to 70%, which is huge - devastating in fact."
Matt Furniss, Cabinet Member Highways, Transport and Economic Growth at Surrey County Council, said, 'This continues to be a highly complex incident involving a number of investigations led by our Highways Officers and other agencies, including specialist teams and utility companies.
'We are continuing to update local residents and businesses as we progress through each stage of the process. We're also looking at how we can minimise the impact on local businesses while the necessary road closures are in place.
'Thorough investigations need to continue to understand the cause of the collapse and subsequently how we fully and effectively repair the area. We hope to have the road re-opened during December this year, but our focus will be on ensuring the road is safe to use so the exact date will be confirmed once we are fully assured of this.'