Autonomous monitoring of nearshore geomorphology and hydrodynamics to assist decision making in coastal management, using shore-based radar systems: A case study on the Fylde peninsula, UK

Nearshore areas can be incredibly dynamic and therefore are difficult to monitor using traditional survey methods that typically provide only a snapshot of the physical conditions at the time of survey. These snapshot data are often re-used in the design of coastal defence interventions at a later date due to the high cost of data reacquisition over large areas. In this paper, a novel solution to large-area, continuous coastal monitoring is demonstrated. A shore-based radar station has been designed to collect image data within a 6 km range and derive a number of datasets including intertidal topography, subtidal bathymetry and surface currents. These data are then used in the development of beach management options to inform the Wyre Beach Management Outline Business Case which is currently being developed by Jacobs UK. At the time of writing, 10 weeks of data have been processed and have revealed the migration of sedimentary features along Rossall beach. Results derived using the radar system support anecdotal, previous scientific observations and modelled indications of sediment migration vectors, while revealing more detail on typical sediment fluxes along with system responses and recovery due to storm events. It is anticipated that this system will be the first of many permanent stations around the UK coastline, allowing a near-real time digital twin of the nearshore zone to be created and constantly updated. These datasets will form a crucial long-term evidence base for planning the most cost-effective coastal defence interventions and monitoring their effectiveness in response to variations in storminess, erosion and coastal squeeze being seen in the close vicinity of many vulnerable coastal areas.