Pervious concrete
Description:
Concrete is made from rock, sand and Portland cement. Think of the
cement as the glue that holds everything together. If you leave out the
sand, you end up with something that looks like a big rice crispy
treat. Because there is no sand to fill in all the little holes, this
type of concrete allows water to go right through it.
Advantage to user:
Pervious concrete allows great freedom in landscape design. You can
plant trees right next to the pervious, making for very attractive
parking areas and walkways.
Savings to pocketbook:
Since water drains right through pervious concrete, you don’t need to
engineer for drainage or build costly retention ponds.
Savings to the planet:
Pervious concrete is much cooler than asphalt, reducing the “heat
island effect.” Pervious concrete allows natural groundwater recharge
instead of going into storm drains.