Abstract: The paving system has a perforated pavement covering a deep substrate of mainly hard nodules or shells, the whole being surrounded by impervious walls to provide temporary storage in the interstices for chemical spillage or flood water, wherein liquids may be chemically treated or biologically decomposed, and from whence the rate of outflow may be regulated, the pavement consisting of preformed pavings of brick, concrete or other material, laid edge to edge without mortar or cement, and these pavings can be perforated or notched to allow liquids to run down into the substrate. The pavings are laid on a screen which filters out solid particles to reduce clogging. The system allows biological substances to grow, or be introduced, with or without additional nutrients, and allows chemical treatments to be introduced, from above, when needed. The whole pavement system can be lifted out for cleaning or, substitution, and relaid as new.