An accurate and easy-to-understand property-level, flood risk model which provides a high-resolution, 5-metre flood map consistently across the whole of Great Britain. Flood maps for Northern Ireland and the Channel Islands (Guernsey, Jersey) are also available and are licensed separately. UKFloodMap4™ is used to visualise, assess, and understand potential flood risk by insurers, government agencies, property developers, property owners and emergency responders.
UK FloodMap4™ considers multiple flooding sources, each modelled separately to provide flood footprints and flood depths (with flood-depth codes) for six return periods. The product models 30% more rivers than other products by modelling further up the catchment area. It uses Environment Agency LiDAR remote sensing data, supplemented by Bluesky’s Digital Terrain Model data. The LiDAR data covers the majority of the UK’s residential and commercial properties (82% of GB properties and 64% in Northern Ireland).
UK FloodMap4™ makes use of Ordnance Survey VectorMap District building outlines and land cover to model infiltration and drainage rates. The modelling approach is guided by the UK Centre for Ecology and Hydrology methodology to simulate complex river (fluvial) flood flows, tidal storm/surge, and intense rainfall-driven (pluvial) urban flood events, taking into account distribution of rainfall intensity over time, land cover types (roughness), and varying drainage and infiltration characteristics.