Dave started his presentation by stating that a major concern today is the effect of covering land areas with non-permeable pavement. The affects on the environment have become increasingly harmful. An alternative is to use permeable paver systems. These installations are environmentally friendly, because they allow the water to drain through some or all of their covering, so it does not run off into the street.
There are three basic types permeable pavers:
- Porous concrete
- Interlocking concrete
Porous concrete is not good in areas of the country where freezing and thawing occurs. Therefore, it is not used in Central Pennsylvania. The other two choices are available in this area. Of those, the Interlocking concreate is the most popular here. The joints of the interlocking concrete are permeable, allowing the water to flow through. It is then treated in the substrate before being released underground.