Patent ID: 8555586

Claim:
A structure for drainage and water-retention a plurality of structural modules arranged adjacent each other, each module comprising a load bearing base unit having a peripheral wall, a top wall and a bottom wall spaced therefrom by at least one supporting element so as to define a volume between the top and bottom walls, the base unit being provided with apertures through the peripheral wall and the top wall to permit the flow of liquid into and out of the volume, and wherein at least a first plurality of the modules each contains a porous foamed polymeric material which occupies a substantial portion of the volume within the base unit and absorbs and retains substantial quantities of water that pass into the enclosed volume through the apertures; and further comprising a second plurality of the structural modules in which the volume is free space so as to permit the free passage of substantial quantities of water that pass into the enclosed volume through the apertures; wherein the structural modules of the first plurality and the structural modules of the second plurality are arranged adjacent each other in alternating fashion so as to provide alternating portions of polymeric material and free space.