Although it is sometimes difficult to balance development with protecting natural resources, utilizing pervious concrete on parking lots and walkways is a step in the right direction.


Although it is sometimes difficult to balance development with protecting natural resources, utilizing pervious concrete on parking lots and walkways is a step in the right direction.

May 22 the Pike County Conservation District and Kiley Associates, LLC hosted a pervious concrete workshop led by Ken Crank, director of Concrete Promotion for the Pennsylvania Aggregates and Concrete Association. The event was held at the PPL Environmental Learning Center in Hawley with 65 participants including design professionals, contractors, community association members and municipal officials.

Crank explained that one of the ways to manage stormwater on a construction project is by utilizing pervious concrete. Pervious concrete is a mix of coarse aggregate, cement, water and little to no sand. This mixture creates pores that allow rainwater to filter through to underlying geotextile and aggregate stone layers that allow for percolation of water back into the ground.

On traditional parking lots, rainwater hits the surface, increasing the temperature and rate of flow of the water, which is carried off the parking lot rather than seeping into the ground. This stormwater runoff then enters streams and lakes carrying with it pollutants that have been captured on the pavement.

Pervious concrete can help meet the environmental demands of reducing storm water runoff, recharging groundwater, and more efficiently using land by reducing the need for large retention basins and other management devices. Use of this and other stormwater Best Management Practices (BMPs) are recommended by both the US EPA and the PA DEP.

One of the myths regarding pervious concrete is that it cannot be used in locations with regular freeze-thaw climates. Pervious concrete has been placed in freeze-thaw climates for over 15 years including projects in the Poconos, New Jersey and Maryland. These surfaces include parking lots, driveways, sidewalks and nature paths.

Justin Hoffmann, P.E. of Kiley Associates, LLC reviewed some of the design considerations for using pervious concrete to meet NPDES permit requirements and protect water quality. He gave examples of how the product was used in designs of land development projects in Pike County.

After the classroom discussion, participants joined the speakers in the lower parking area of the PPL Environmental Learning Center for a demonstration of the infiltration properties of a pervious concrete parking area that had been cured the day before. Mercereau Masonry, Inc. demonstrated the steps involved in installing pervious concrete, including the construction of the subsurface and the pouring, compaction and jointing of the mixture. Wayne County Ready Mix Concrete Company supplied the pervious concrete for the demonstration.

To view the demonstration area you can visit the PPL Environmental Learning Center lower parking lot. For more information on pervious concrete visit www.pacaweb.org or www.perviouspavement.org.