Work has started on a £250,000 sinkhole repair project in West Dunbartonshire.

A section of the Kilbowie Road in Clydebank collapsed last month due to a mineshaft under the route which was not recorded on any historical maps of the area.

Experts from the Coal Authority have taken responsibility for the site and repair works, which will take between six – eight weeks to complete.

While the six-metre deep hole is visible from the road surface, further investigations revealed a shaft stretching down 56 metres to a total depth of 62 metres – the equivalent of 14 double decker buses.

Repair works got underway last week, with stone, pressurised grouting and a concrete plug needed to be poured down the hole to stabilise the surface. Once the shaft is filled and capped, work can begin on filling the gap above the shaft and the road reconstruction. This phase could take up to 16 weeks to complete due to complicated significant infrastructure underneath the road such as pipes, drains and power and utility cables.


Tim Marples, Head of Public Safety and Subsidence for the Coal Authority, said: "The unrecorded shaft at Kilbowie Road is one of our top operational priorities and our prime concern is the safety of the public.

"Our engineers have designed a solution to safely fill the shaft and repair the road and we are working with West Dunbartonshire Council and the utility companies on our proposals.

"This particular repair is complicated by the exposed utility services within the 62 metre deep void, which we are working to protect.

"From our experience, the work will take between six to eight weeks to complete and cost in the region of £250,000.

"Our aim is get the road re-opened as soon as possible to minimise the impact on local residents and traffic."

(LM)