Orthomosaics of the study area were generated by drones on 19 September 2024 and 18 September 2025. They were created from 895 images (2024) and 1,282 images (2025), captured at altitudes of 120 meters (2024) and 100 meters (2025) using the DJI Mavic 3E RTK (2024) and Mavic 3M RTK (2025) drones. The ground resolutions were 3.19 cm/pixel (2024) and 2.63 cm/pixel (2025). The surveyed area covers approximately 1 km², and the orthomosaics were resampled to a resolution of 10 cm/pixel.

Digital Surface Models (DSMs) of the study area were generated by drones on 19 September 2024 and 18 September 2025. Each pixel represents the elevation value of the terrain at the time of the survey. These DSMs were generated from 895 (2024) and 1,282 images (2025), captured at an altitude of 120 (2024) and 100 meters (2025) using the DJI Mavic 3E RTK and Mavic 3M RTK drones, with ground resolutions of 3.19 (2024) and 2.63 cm/pixel (2025). The surveyed area covers approximately 1 km². The DSMs were resampled to a resolution of 20 cm. The vertical coordinate system used is NGF IGN69.

The bathymetric DEM of the atlantic facade with a resolution of 0.001° (~ 100 m) was prepared as part of the HOMONIM project. It encompasses part of the North Sea, the Channel and the Bay of Biscay. Offshore, this DTM extends beyond the slope to approximately 4800 m depth. The DEM is designed to be used in hydrodynamic models in order to produce high-precision forecasts for coastal water levels and sea conditions and therefore improve the pertinence of the Waves-Submersion monitoring programme. This product is available with the Lowest Astronomic Tide (LAT) or the Mean Sea Level (MSL) as a vertical datum.

The update of the coastal topo-bathymetric DEM of the Gironde estuary - upstream with a resolution of 0.0002° (~ 20 m) was carried out in the third phase of the HOMONIM project. This DEM covers the upstream part of the Gironde estuary, from Pauillac to Bordeaux on the Garonne and to Libourne on the Dordogne. It is complementary to the DEM covering the downstream estuary (between Pauillac and the mouth of the Gironde). The DEM is intended to be implemented in hydrodynamic models in order to produce forecasts as accurate as possible of water heights and sea states at the coast to improve the relevance of the Wave-Submergence Vigilance. This product is available with either the Lowest Astronomic Tide (LAT) or the Mean Sea Level (MSL) as a vertical reference.