Green Ink Copywriting: County materials collaborates in permeable paver test plot project

Wisconsin engineers will soon have another arrow in their quivers when it comes to designing storm water control projects that qualify for environmental credit, thanks to a new permeable paver test plot project supported by County Materials Corporation.

The permeable paver project will begin construction April 1, 2014 at the Sycamore Dog Park, Madison, WI. The plot will enable researchers to accurately assess the effectiveness of permeable pavers in diverting and filtering storm water runoff. While not the first permeable paver research facility, this one is unique in its comprehensiveness. By request from the WDNR and WDOT the plot includes three cells, one for permeable pavers, one for permeable concrete and one for permeable asphalt. In addition, it is lined on the bottom, and includes separate equipment for measuring influx, outflow, and overflow. The design will enable researchers to measure the quality and amount of all water entering and exiting the system.

Permeable pavers are widely recognized as an effective solution for reducing total suspended solids (TSS) levels in storm water to EPA-mandated standards. Permeable pavers are often the preferred system where space is at a premium; they can also help avoid potential liability associated with retention and detention ponds that are open bodies of water in areas where children and adults may be present. However, the State of Wisconsin has not yet developed technical standards for permeable pavers due to a lack of data detailing the technology’s performance in the field.

“Without technical standards in place, engineers often hesitate to specify permeable pavers, even in cases when they may otherwise be the best option for a particular project,” comments Bob Roehrig, an architectural sales representative at County Materials and one of the driving forces behind the project. Roehrig also serves on the Wisconsin DNR’s Standards Oversight Council to represent permeable pavers. He notes the importance of obtaining data from the test plot to ensure engineers have up-to-date standards for viable storm water management options.

Data from the test plot will help alleviate this problem. “One of the keys to doing these technical standards is having good data,” says Roger Bannerman, an environmental specialist with the Wisconsin DNR and member of the Standards Committee for permeable pavers. Road salt has become a serious issue for Wisconsin’s environmental quality, Bannerman adds. “Permeable pavers can significantly reduce the amount of salt that ends up in the water supply – some say by up to 70%. (Having standards in place) will make it easier for people to use permeable pavers.”

Although Bannerman says the first draft of the standards for permeable pavers will likely be ready before testing on the Madison project begins, he feels the results gained will prove invaluable in the future. “A standard like this is a living document. New research will often change our recommendations. Every time we improve them it makes them easier to implement. The bottom line is to do the most cost effective thing possible and make sure we spend our money wisely in Wisconsin.” The data is also likely to affect best practice recommendations in other areas of the country and the world, says Bannerman.

County Materials provided funding and permeable pavers for the test plot, and the company has been instrumental in identifying additional supporting partners, including manufacturers, engineers and contractors. The Wisconsin DNR is contributing $45,000 to maintaining the project over two years. Also helping to fund the test project is the WDOT with $90,000 and the U.S. Geological Survey who are contributing $10,000 and $38,700, respectively. Overall cost of the test plot will be $225,000 in the first two years.

The test plot is expected to be ready for use by June of 2014, with initial results coming in by late summer. Per project requirements, test data will be collected for up to two years, or approximately 18-21 storms, to validate information studied by the USGS and WDNR.

County Materials Corporation is a family-owned, American-based manufacturing company and leading source for construction and landscape products. Its headquarters are in Marathon, WI, where it was founded in 1946. The company has grown into a diversified organization that supplies products for growing communities at more than 44 locations across the Midwest. For more information visit