The “Maximum tidal current speeds for mean spring tides” product provides information on the maximum speeds reached by tidal currents on mainland French coasts (English Channel and the Atlantic). These data can be used to identify areas subject to the strongest surface tidal currents and to characterize the maximum current intensity reached during a tidal cycle under mean spring tide conditions. The data are provided in shapefile format, with polygons associated with maximum current speed values, without any temporal or directional information. The values are expressed in knots.

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.

The update of the coastal topo-bathymetric DEM of the Pertuis charentais at a resolution of 0.0002° (~ 20 m) was carried out in the third phase of the HOMONIM project. The DEM extends from the terrestrial domain to about 60 meters depth over all the pertuis (pertuis Breton, pertuis d’Antioche and pertuis of Maumusson). 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.