Abstract: A process for the desalinization of sea water which includes a barrier buried to a depth below the low tide water level in a sandy beach, and a collector vault or well buried in the beach behind the barrier, the well having an opening in its side for receiving water passing through the barrier. The barrier is filled with selected filter materials, and the sand in the area between the barrier and the well is treated with a selected material. The barrier extends through a water-permeable layer of crushed or fossilized shells naturally occurring beneath the sandy beach. The well opening is positioned within this shell layer. After a period of pumping, desalinated water will appear in the well and may be pumped out of the well. Whenever the water in the well is pumped below a particular level, a new supply of desalinated water will flow in through the opening in its side from the barrier.