WATER POCKET USING A PERCOLATION WELL FOR THE IN-GROUND STORAGE OF PERCOLATED RAINWATER

摘要

The present invention relates to a water pocket capable of preventing the reverse flow of rainwater from a drain by reducing the rate of water outflow, by percolating a portion of the rainwater, which concentrates at a sump of the drain during flooding when the water level suddenly swells, deep underground through the water pocket. In order to achieve the above aim, a water pocket for preventing the reverse flow of rainwater from a drain according to the present invention comprises: a rainwater inlet tank connected to a side of a drain sump via a connecting pipe, into which rainwater collected at the sump is admitted through the connecting pipe; a percolation well formed in-ground below the floor of the rainwater inlet tank; a first perforated pipe having a cylindrical shape and a plurality of through-holes defined in the periphery thereof, and which is inserted within the percolation well to define a space between the walls of the percolation well; a second perforated pipe having a cylindrical shape and a plurality of through-holes defined in the periphery thereof, which is inserted within the first perforated pipe and has a non-woven fabric coupled tightly to an outer portion thereof to filter impurities; a filter layer filled with aggregate in a space between the percolation well and the first perforated pipe; and a filter mesh fastened so as to block the top of the first perforated pipe, wherein rainwater is discharged through only the outlet of the sump during normal flow conditions, and during abnormal flow conditions, rainwater that flows into the rainwater inlet tank through the connecting pipe is percolated and stored in the ground through the first and second perforated pipes and the filter layer.