Permeable paving has the benefit of allowing water to infiltrate and recharge the ground water rather than run off into surface waters. Some permeable paving is compatible with turf or other groundcovers, and thus can be cooler in the summer than traditional paved surfaces.
Permeable pavers may have rainwater collections systems installed underneath, as in the RainXchange(TM) system demonstrated at Aquascape headquarters in St. Charles, Illinois. (http://www.aquascapeinc.com/why_rainxchange
Permeable paving comes in various styles. It may consist of pavers that have an opening in the center which can be filled with gravel or plants.
Poured concrete that has a different composition than traditional concrete, giving it a more porous quality, is called pervious concrete pavement.
SOURCES AND FURTHER READING
Pervious Concrete Organization. http://www.perviouspavement.org/.