Figure 1. Pervious pavers are designed to promote vehicular and pedestrian traffic in land areas that would otherwise be unusable due to stormwater retention. Impervious pavement systems, such as asphalt, promote heat and stormwater runoff. Pervious pavers provide a natural way to let water percolate to the ground, while still offering a durable and aesthetically pleasing pavement surface. http://pavermodule.com/prod_enviro.asp.
Credit: Hanson Paver Products, Inc., Environmental Pavers, 2006.