• Underwater foundations - Submerged earthworks, rock excavation, explosives - Rockfill, gabions - Inspection of sewers, cleaning of grids - Sewage treatment plant - Tunnel work, Repair - maintenance : Drilling, injection - Underpinning - Anchoring, formwork - Weir reinforcement - Cavity lining - Renovation of lock gates - Music note joints Special techniques: Video - Thermal lance cutting - Underwater welding - Descaling of 700 bar drains - Needle cofferdams