There are three types of Concrete Block Permeable Pavement:
System A: total infiltration All water falling onto the pavement filters down through the joints or voids between the concrete blocks, passing through the constructed layers below and eventually into the sub-grade. The sub-base layer may act as a temporary storage device.
System B: partial infi ltration Similar to System A but with a series of perforated pipes or fin drains at the formation level to allow the remaining water to be drained to other systems such as sewers, swales or watercourses.
System C: no infiltration Allows for the complete capture or attenuation of the water using an impermeable flexible membrane placed on top of the formation level. Pipes or fin drains transmit the water away as with System B.