“We’ve just put out the parameters that tell the designer what we’re looking at in more specifics,” he says. “We haven’t had a lot of people take advantage of it yet.”

The other problem he sees is that designers and property owners – including homeowners – don’t yet have the knowledge and examples to inspire them. For instance, he talks about a recent project he reviewed where the homeowners wanted colored stamped concrete in their driveway.

Soil 6-17-07 010Click photo to enlarge“I said, ‘How about if you put a border around some of the flat areas in your driveway in pavers?’” Sholly relates. “They could have put a filtration system under the paving just by putting in a few extra stones, but they went with the stamped concrete and built a totally separate filtration system.”

He adds that many are still reluctant to go to products such as pervious pavers and design features such as rain gardens because they aren’t familiar with them.

However, down the road at Villanova University, Dr. Robert Traver, the head of the Villanova, Pa., school’s stormwater project, is doing his best to get students in the environmental engineering department thinking about stormwater options.

He explains that about 10 years ago, the issue of stormwater moved away from looking only at containing floodwaters and started looking at water quality and aquifer recharge.

“We figured that since nobody had ever done it before, we needed to do a lot of research in understanding how these things work,” Dr. Traver says. “That’s what we’ve been doing since then: building best-management-practices sites all over our campus and testing them.

“At the same time, they’re demonstration sites where, when municipal officials think all this stuff is nasty, we can show them it’s friendly and it looks great.”

The projects Villanova students are studying include a green roof, stormwater wetlands, bio-retention rain gardens, rain barrels, and multiple pervious concrete and porous asphalt applications.

“We also have an infiltration trench where the overflow is made of pavers,” says Traver. “There are some other things we’d like to do, but we’ll get there eventually.”

GROWING MARKET

For the designer or contractor faced with the need to put down some sort of pervious surface, the range of products is broad – and growing.

Andy Vander Woude, chief executive officer (CEO) of Minneapolis-based VAST Enterprises LLC, claims pervious paver uses have been growing at a rate of about 50 percent per year in recent years, although the material still constitutes only about two percent of the total paver market.