Going Green With Pervious Concrete
Pervious concrete as a paving material is experiencing "unbelievable growth," says Indiana Ready Mixed Concrete Association (IRMCA) Executive Director Pat Kiel. "Everyday people are calling and asking about it."
Gaining momentum in the Midwest, pervious concrete is viewed as an effective means to address key environmental issues and support green, sustainable growth. By capturing stormwater and allowing it to seep into the ground, pervious concrete is instrumental in recharging groundwater, reducing stormwater runoff, and meeting stormwater regulations.
Pervious concrete is a structural concrete pavement that "drinks" water. It has a porous structure allowing water to pass directly through the pavement, into a storage layer of stone underneath, then into the soil naturally. Pervious concrete allows water to soak through it rather than running off the surface, eliminating runoff that would ordinarily flow into stormwater sewers and carry oil and other pollutants with it.
In addition to reducing stormwater runoff, concrete industry officials report that pervious concrete eliminates the need for detention ponds and other costly stormwater management practices; replenishes water tables and aquifers; allows for more efficient land development; minimizes flash flooding and standing water; prevents warm and polluted water from entering streams; and mitigates surface pollutants.
Developers are using pervious concrete for parking lots to increase utilization of commercial properties. Placing pervious concrete pavement in parking lots can reduce the need for large detention ponds because the pavement acts as a detention area, says Jerry Larson, promotions manager for IRMCA's Northern Region. And a pervious concrete parking lot will help reduce demands upon sewer systems.
University Park Mall Project
In Mishawaka, Ind., the Simon Property Group recently installed pervious concrete at its University Park Mall property. This 10,000-square-foot test section will be monitored by Simon for performance and durability, and will become a model for design as Simon looks for stormwater management methods and green building practices for its shopping centers and commercial properties nationwide.
"It's a way for Simon to understand the environmental benefits of the product," says Curt Tappendorf, P.E., civil engineer, architecture & engineering for Simon Property Group. "We were very impressed with the installation and mix design."
Simon worked in conjunction with IRMCA to coordinate the University Park Mall project, which involved the placement of 6 inches of pervious concrete on top of 6 inches of aggregate base. After workers for Fort Wayne, Ind.-based Hagerman Construction Corp. poured the concrete, an environmentally safe soybean water-repellent, "THE BEAN," was applied to help protect the surface, especially during the curing period. THE BEAN is manufactured in Indiana from Indiana soybeans and is distributed by C2 Products Inc., Noblesville, Ind.
A new product — "JELLY BEAN," which C2 Products plans to announce at the 2008 World of Concrete — was also utilized on the project. According to C2 Products, this specially formulated pigment pack — when added to The BEAN — turns a sealer into a stain and seal.
"The JELLY BEAN adds a color pigment to the pavement," says Larson. "For this particular application, we used a white pigment because we want high reflectivity from the lights above — providing a much brighter, safer parking lot."