X-band radar as a tool for monitoring natural coastal behaviour and potential development impacts

Abstract

ABSTRACT This paper reports ongoing exploration of X-band radar as an operational monitoring tool for coastal infrastructure development. Data have been continually gathered since 2013, helping a major energy developer (EDF Energy) better understand shoreline processes at a proposed new nuclear power station at Sizewell, UK, to inform considerations of engineering design. The continual coverage provided by the radar enables greater confidence in defining natural variability and therefore enhanced assurance to regulators of the integrity or suitability of the site. Sizewell is located on a low-lying, soft coast with at least 1000 years of recorded (net) retreat. The commercial X-band system deployed calculates hydrodynamic data (suitable for managing navigation and vessel access), but this paper illustrates using radar images to establish the pre-construction baseline geomorphic behaviour of the nearshore, including a steep pebbly beach-face, two shore-parallel sub-tidal sandbars, and a large sandbank, 2 km offshore, which significantly affects nearshore hydrodynamics. Data illustrate baseline geomorphic behaviours that were previously unobserved, despite beach profiling records over 20 years. The temporal and spatial scales of natural changes are compared with the potential impacts of the development, including dredging (and spoil deposition) for navigation channel maintenance and the presence of nearshore structures, all of which would affect shoreline processes and so would need to be monitored (and any impacts managed) as development proceeds. Finally, the paper considers where the utility of X-band radar as an operational monitoring tool may surmount the barriers that have limited its uptake outside of academic/research circles.