ForConstructionPros.com

Pervious concrete. No doubt you've heard of it and its "green" possibilities. But how much do you know about pervious concrete and its presence in today's concrete industry?

Pervious concrete is similar to conventional concrete but manufactured without most or all of the sand in order to create voids allowing water to flow through the concrete and drain through the subgrade for filtration, ground water recharge and reduction in overall stormwater runoff, says Dan Huffman, vice president of national resources for the National Ready Mixed Concrete Association (NRMCA). Pervious concrete has been in limited use in Europe for over 100 years but took hold in the United States about 30 years ago, Huffman adds.

Pervious concrete started in Florida on small projects but since then has spread across the states and applications have grown in size. Pervious concrete has gone from "experimental" projects to larger installations, say Scott Erickson of Evolution Paving Resources, a company in Salem, Ore., that is dedicated to improving the quality of pervious concrete.

"Five or 10 years ago we were talking driveways and sidewalks. Now, while those are still happening all over the place, we're also talking large commercial and multi-acre facilities with pervious concrete," Huffman adds.

The need for pervious has also grown, and today the proper use of pervious concrete is among the recommended Best Management Practices (BMPs) of the US Environmental Protection Agency (EPA) for compliance with federal stormwater law requirements and is otherwise accepted for use by many local stormwater management agencies across the country. Pervious allows for increased site optimization because in most cases its use should totally limit the need for detention and retention ponds, swales and other more traditional stormwater management devices that are otherwise required for compliance with federal stormwater regulations on commercial sites of one acre or more, Huffman says.