Bentonite waterproofing system used for waterproofing groundwater (constant, fluctuating or percolating) of underground concrete structures (slabs and foundation walls against diaphragms, piles, Berliners, existing foundations or disposable formworks) and buildings such as garages, cellars , warehouses, vaults, taverns, depots, car silos, underpasses and tunnels. This process, combined with the exceptional self-confinement, keeps its waterproofing power unchanged.