Flat Cliffs, Filey, UK

Scarborough Borough Council

A community of approximately 30 houses is located on a landslide in glacial deposits that moves periodically due to a combination of toe erosion by the sea and intervals of heavy rainfall.

The houses are not in danger of being destroyed, but small movements of the landslide can cause the access road, water supply and sewage pipes to become distressed.

Working for Scarborough Borough Council, the landslide has been instrumented by Jacobs (previously CH2M and Halcrow) with a range of traditional geotechnical instruments such as inclinometers and piezometers. The aim is to help understand the geometry of the landslide and the factors that result in movements.

Progress and impact

An active waveguide with a Slope ALARMS sensor was installed through the landslide in September 2011, and continuous monitoring of acoustic emission is ongoing.

The rates of acoustic emission generated over time are being compared with measurements of deformation made using an adjacent inclinometer casing.

A period of movement that occurred after the 2013-14 winter revealed the shear surface to be at approximately 14m below ground level. This period of movement was also detected by the Slope ALARMS system.

Published papers

Dixon N, Moore R, Spriggs MP, Smith A, Meldrum P and Siddle R (2014) Performance of an acoustic emission monitoring system to detect subsurface ground movement at Flat Cliffs, North Yorkshire, UK. IAEG XII Congress, 2, 117-120, Turin.