Sample Sites Near a major river confluence with a history of flooding, the site of interest is located within the red circle. Protected by a bund bounding the river, LiDAR revealed that a road forms a second, informal line of defence. A cross-section located across the LiDAR confirms this interpretation. A site is shown by Natural Resources Wales’ mapping to be in the flood zone. LiDAR mapping shows the site to be raised over a metre above the river channel and floodplain, on the site’s eastern margin. Hydraulic modelling later demonstrated that the site would be flood free. Environment Agency mapping shows an existing office block to be in the flood zone but hydraulic modelling shows that even the 1:1,000 year flood would not quite reach 6.0 mAOD. LiDAR shows the site to be a little over that level, while showing a safe evacuation route.