A LEADING geotechnical engineer has said sinkholes such as the one which opened up in Ripon last week should be filled as quickly as possible, while residents living in the area have been put on alert to further movements.

Ahead of inspecting the 15m diameter and 30ft deep sinkhole which led to properties being evacuated in Magdalen’s Road, Geotechnical Consulting Group Tony Bracegirdle said if rapid action was not taken the ground around the hole could “relax”, causing damage to nearby buildings.

Harrogate Borough Council said residents of four of the evacuated properties have been advised not to return to their homes on safety grounds.

The authority added some residents of the eight other properties affected by the sewerage issues have remained in their homes, but have been advised if they see any cracks or hear unexpected noises to vacate the building and contact emergency services.

It said contractors from an insurance company were on site examining options to stabilise the sinkhole and that a garage had been dismantled by hand to allow access to the area.

A Harrogate Borough Council spokesman said: “Our responsibility is to protect the public from any known danger.

“We will continue to liaise with the households’ insurance companies to ensure we are aware of any building control issues and will continue to provide advice and support for those affected by the sinkhole.”

Meanwhile, Yorkshire Water is continuing its investigations to devise a plan to repair the sewer system on Magdalens Road, which has been completely destroyed by the sinkhole. That work can not begin until the site is deemed safe.

While a much larger sinkhole which appeared on a main road in Fukuoka, Japan, was filled with concrete in just two days this week, engineer Mr Bracegirdle said repairing surface layer collapses in Britain often took much longer due to bureaucracy.

He said : “The engineering challenge is to get enough concrete into the hole as quickly as possible and that’s not very challenging at all. It’s a constant squabble about who takes responsibility. Local councils are strapped for cash, so they look to pass the buck to insurers.”

It is understood the work in Ripon could be undertaken in the coming weeks due to authorities’ experience at dealing with sinkholes in the city.

Close to the Magdalens Road sinkhole, previous collapses occurred in 2014, 1979 and 1980, and across Ripon as a whole a sinkhole appeared every two to three years in the 1980s and 1990s.