When I was at the Green Summit a couple weeks ago I saw some
vendors demonstrating pervious concrete which is porous concrete
that water can flow through to the ground. Turns out this is
quite a useful characteristic for some applications where
traditional non-pervious concrete is usually used such as
parking lots, drive ways, and paths. It reduces the heat island
effect, helps recharge aquifers, saves space, and reduces toxic
runoff. Probably one of the greatest benefits of this is that it
reduces the heat island effect. Concrete already reflects more
heat than asphalt because of its light color, but pervious
concrete goes a step further. Since it is porous it allows
moisture from below to evaporate which acts to cool the
concrete. One of the vendors also said that since it has less
thermal mass it doesn’t absorb as much heat. Another benefit is
that pervious concrete can help recharge aquifers. Instead of
rainwater being diverted into storm drains or water retention
basins the water goes straight down to th