Key tests after Lancashire reservoir road collapse

Lancashire County Council is investigating the safest ways to repair a wall near Lower Rivington Reservoir which was damaged during a major storm earlier this year.

Temporary traffic lights have been in place on Bolton Road, Anderton, since part of a retaining wall which supports a steep slope on the opposite side of the road to the reservoir collapsed during Storm Ciara in February.

One lane of the road remains closed for safety because the foundations supporting a section of the roadside safety barriers have been undermined, and heavy vehicles need to be kept away from the slope while assessments to ensure its stability are completed.

A geotechnical assessment is underway, with boreholes having been drilled to monitor any movement of the slope, and soil samples being analysed to give more information about its strength.

The results will inform the design of a scheme to repair the retaining wall towards the end of this year or in early 2021.

County Coun Keith Iddon, cabinet member for highways and transport, said: “I’m sorry for the inconvenience to road users in this area over recent months due to the temporary lights on Bolton Road, and I know it must be frustrating for people who live in this area.

“The lights are going to be in place for some time yet, however I wanted to let people know why they are needed and what we’re doing to repair the wall so we can fully reopen the road.

“It is difficult to fully see from the road, however, there is a steep slope of around 10 metres directly beside it, and a section of the retaining wall which supports the road has completely collapsed.

“The partial closure of the road is needed as the safety barrier system has been damaged, and the road is not supported as it should be without the wall in place.

“Repairing the wall is not a simple task as it is an old structure which is located in an awkward position on top of the dam. Before work can begin we need to check whether any further action may first be needed to stabilise the slope, and some time is needed to carry out this monitoring.

“We will have this information in the coming weeks, and if the slope can support them, we may be able to install temporary barriers allowing us to remove the temporary lights, with some less disruptive traffic safety measures.

“This information will also allow our engineers to begin designing a repair scheme for the wall, and a drainage system which was contained within it.

“Our aim is to carry out the repairs towards the end of this year, or early in 2021, and I’m grateful for people’s continued patience while the temporary lights are still needed.”