What the is the difference between permeable and porous asphalt pavement? While there are differences in the technical definitions of permeable and porous, these terms are interchangeable regarding asphalt pavement. It is especially well-suited for parking lots, walkways, and sidewalks in a variety of commercial developments resulting in a high return on investment, years of durability, potential grants or tax breaks.  All while simultaneously helping the environment.

Permeable asphalt pavement provides the structural support of conventional pavement, but allows stormwater to drain directly through the surface, which is load-bearing, into the underlying surface, consisting of stone base and soils. This technology intercepts and reduces stormwater runoff. During a rain event, stormwater flows through the porous surface, drains into the crushed stone sub-base beneath the pavement, and then remains stored temporarily. The storage time depends on the soil properties. The stormwater can infiltrate into the soil or outlet through the underdrain.

How long can this sustainable paving solution last? Is it too good to be true?  The truth is porous asphalt pavement can last up to twenty years before showing cracks or potholes! From playgrounds to high-volume highways that carry heavy trucks, it is certainly an attractive alternative to traditional impervious asphalt paving.

-Hanna Casswell