Peacehaven & Telscombe Cliffs Project

Coastal cliff recession represents a significant risk to both people and infrastructure. It is important that we are able to effectively monitor these environments to inform future decisions regarding the management of the coastline and to forecast future erosion rates, in order to support the resiliency of the UK’s coastal communities.

Approximately 3,300 km of the coastline of England and Wales is formed of sea cliffs, with only 6% currently defended. Within the UK, the Environment Agency and the Department for the Environment, Food and Rural Affairs (DEFRA) have a statutory responsibility to mitigate coastal hazards through shoreline management plans. These plans rely on reliable estimates of coastal erosion and its consequences over the next 100 years.

However, in many cases, shoreline management plans are based on coastal erosion data derived from historical maps and aerial photographs. Positional errors in these maps and photographs (the difference between location as represented in a map or a photograph and the actual location of the coastline) are often comparable to erosion rates, which makes producing reliable information about the rate of coastal cliff recession difficult.

Below: A) formation of a wave cut notch along the base of cliff relative to 16/09. B) Standard deviation of measured erosion with elevation for the period 16/09 to 20/09. Dates given in yy/mm.

Geomorphologists at the University of Sussex, who study the evolution of the coastline, are conducting research involving new technologies to achieve high-precision monitoring of sea cliffs. This has allowed for much more accurate estimates of erosion and for more robust predictions of coastal change. High-precision monitoring undertaken at Telscombe, East Sussex has produced the first quantitative estimate of coastal cliff recession that incorporates climate change predictions. Ongoing work has also demonstrated the formation of a wave cut notch at the base of cliff. For the first time, these data link the rate of notch formation to amount of wave energy delivered.

The use of Unmanned Aerial Vehicles (commonly known as drones) to undertake this high precision monitoring offers a relatively low-cost method for generating more accurate erosion data for long sections of the coast, which can then be used to inform the management of any risks posed by future cliff recession more effectively. We recommend that DEFRA and the Environment Agency explore the potential to make increased use of these new technologies to facilitate more accurate monitoring of coastal erosion across the UK.

  DJI S1000 Octocoptor drone