THE WILTSHIRE LANDSLIDE ROAD !!!

[Michael Grove]

Join us as here as we explore The Epic Landslide, that

has totally destroyed a very busy through road in the

Wiltshire countryside, near Lyneham.

A ripped up road likened to being hit by an earthquake could take up to a year to fix and cost millions of pounds, a council has said. The B4069 near Lyneham in Wiltshire has buckled in places, leaving huge cracks in the road, due to subsidence. An emergency road closure was put in place on 17 February but police said some drivers were ignoring it, putting themselves and workers in danger.

Wiltshire Council said it was awaiting a report from geotechnical specialists. Local residents claim the subsidence has been getting worse over the last year and that a landslip was inevitable. An investigation is under way into the cause.

[Michael Grove]

Geotechnical specialist Clive Edmonds told NCE that images of the damage - which show the road surface "heaved and then falling away in level" - suggest that "mass movement of the slope has been triggered probably by locally increased pore water pressure build-up in the slope profile leading to renewed landslide activity". He added: "This sort of movement would account for the highly irregular switch-back look along the road alignment and cracking of the surface.” Edmonds explained that the road “coincides geologically with an area where the Jurassic age Stanford Formation (limestone) appears to overlie/overstep the Hazelbury Bryan Formation (sandstone)”. Both of these are underlain by the Oxford Clay Formation.

"The road appears to run along and down the contact between the sandstone and limestone above the clay stratum going downhill away from Lyneham," he said.

“This kind of geological contact tends to be prone to past periglacial weathering effects like cambering and mass movement so is likely to have been affected in the geological past by downslope mass movement of the sandstone/limestone strata over the clay."