STRUCTURE OF UNDERGROUND STORAGE PERMEATION LAYING

PURPOSE:To provide an underground storage permeation laying structure which is large in the storage capacity of rain water, and possible in the effective utilization of the upper face of a permeation pond, and moreover inexpensive in earthwork cost. CONSTITUTION:A benching section 8 which has a depth of the extent of not collapsing of the earth and sand of the wall face 4a of a storage section 4, and is excavated in a stairs-shape is formed, and the benching section 8 is sprayed with cement mortar to prevent the collapse of a side wall. A permeable or water interruptive sheet 10 is spreadingly provided on the bottom and wall face of the benching section 8. After filler 11 such as a broken stone having excellent permeability and sand are spreadingly provided on the sheet 10 on the bottom of the storage section 4 and flattened, a plastic honeycomb block 12 is piled up on the filler 11 in plural layers so as to correspond to the form of the wall face of the benching section 8, and plurality of polyvinyl chloride porous water catching pipes 5a connecting to a water catching pipe 5 through buried material 13 such as the broken stone are provided on the honeycomb block. The porous water catching pipes 5a are covered by a permeable sheet 14, and back filling material 15 such as earth and sand is piled up on the permeable sheet 14 for back-filling.