Paving success with stormwater: ecological paving systems can grow green profits for producers

Concrete Producer, The, Feb, 2005 by Rick Yelton

Chuck Taylor lives for rain. Sure, he's heard the comments about not having enough sense about his habit of standing outside during a downpour. His preference for rain isn't that this contractor enjoys the smell of wet clothing, Taylor's fascination with inclement weather comes from the satisfaction while seeing his company's workmanship perform.

Evidence is today's shower at The Morton Arboretum. Even after this heavy daylong rain in late fall, the parking lot constructed in late 2003 looks dry. Every puddle-free parking space is testimony to the important, increasing acceptance of pervious interlocking pavement. This is especially true when the venue is an influential ecological setting.

The Morton Arboretum, located in Lisle, Ill., 35 miles west of Chicago, is a 1700-acre expanse of carefully designed landscaped projects. Nature conservators and landscape architects worldwide come to view trees and plants in carefully sculptured settings. About three years ago, the director decided to use a planned parking lot expansion as a test of pervious systems he had seen in Germany.

The paving project has been a watershed for Advanced Pavement Technology (APT), Taylor's recently formed pervious pavement design/build firm in Oswego, Ill. An APT-certified contractor was the installer on this high-profile project. Pervious pavers were selected for their ecological advantages. Late last year, the nature conservators, the paver manufacturer, installer, and others, hosted a symposium to acquaint architects and city and building officials with the system.

Taylor believes this market has much growth potential. And the industry seems positioned for more growth even with a strong overall paver market. The Interlocking Concrete Pavement Institute (ICPI) recently reported their annual concrete paver sales in North America for 2003. (See graph on page 32.)

Paver sales in North America totaled 615 million square feet in 2003, with the United States accounting for 530 million square feet. The market is growing at more than an 8% annually.

"This growth shows the continued strength of the segmental concrete pavement market in North America, especially in the residential and municipal markets," says Steve Berry, ICPI's chairman. The residential market continues to account for almost 75% of total paver sales, with commercial at 18%, and municipal at 3%. Unfortunately, ICPI was not able to supply any current information on the size of the pervious pavement market.

Green lights ahead

Land developers, architectural engineers, and building owners are recognizing ecological paving systems as important elements to their new projects, according to Taylor. They find these systems ecological, as they improve a site's water quality because they allow rainwater infiltration and natural groundwater recharge.

Property owners are finding flexible pervious paving systems to be economical. Since these systems often comply with the EPA's Phase II Rule, zoning officials who are aware of the benefits may waive the requirement for retention or detention ponds. For less than the additional cost of a flexible pervious paved parking lot, developers quite often discover they can reduce construction costs by eliminating or reducing the size of drainage and retention systems. "But most owners focus on the benefit they receive from the greater efficiency in land-use," says Taylor.

Another factor in the increasing focus on flexible pervious paving systems is its inclusion in the United States Green Building Council's Leadership in Energy and Environmental Design (LEED) rating system for new commercial construction. The committee responsible for overseeing the nation's fastest-growing building ecological rating system has made stormwater containment a high priority when assessing a site's environmental performance.

Designers usually can receive LEED credits for selecting pervious paving systems in several categories. Reviewers can award credits for using pervious paving systems in stormwater management if it reduces runoff (SS credit 6.2). Designers also can be rewarded when they use a pervious system to help treat water before release (SS credit 6.2). In some cases, using a pervious paver system can earn a credit because some pervious service designs also help reduce potential soil loss and contain the release of suspended solids.

Public work officials also are recognizing the ecological benefits, as reported in the December 2004 issue of PUBLIC WORKS, THE CONCRETE PRODUCER's sister magazine. The movement is spreading from large communities to small towns.

"The use of permeable pavers is increasing all across the United States," said Donna DeNinno, director of marketing for UNI-GROUP U.S.A., an association of UNI Paver manufacturers. "Areas such as the Chesapeake Bay, Minnesota Lakes region, Pacific Northwest, New England, Florida, and California are at the forefront, as they have increasingly restrictive guidelines regarding construction and pollution impact on surrounding surface waters." In 1995, the city of Wilton Manors, Fla., installed UNI-GROUP's UNI Eco-Stone concrete pavers on more than 30,000 square feet of a parking lot serving a recreational facility.