There is no reason why vast parking lots must be covered entirely by pavement. Besides being a heat-trap, paved surfaces disrupt local ecology and cause serious problems with rainwater runoff. Fortunately there is a sensible alternative. Known as grass pavers, these honeycomb-shaped connected pavers (which can be made from recycled plastic), provide the foundation of your driveway or parking lot, allowing grass to grow through and water to be absorbed.
The primary advantage to having a permeable surface is the absorption of rainwater and a reduced need for sophisticated storm water runoff management. Throughout the country, runoff from suburban and urban development unnaturally accumulates and negatively alters stream geography and flow. The millions of gallons that cannot penetrate the ground due to the presence of concrete structures and endless areas of asphalt can not only overwhelm drainage areas, but they also bring considerable pollution into our wetlands.
While the recycled plastic pavers are a good bet, there are countless other permeable surface materials to help you lessen your building’s environmental impact. Usually loose gravel can be added to the spaces in between pavers, or used by itself to complete the driveway. You can also use regular hexagon-shaped concrete pavers, which mean more surface area, but still allows for permeation. An equally effective yet slightly more complex and costly option is Pervious Concrete, which looks like a traditional concrete surface but with small holes and cracks to allow water infiltration.
One of the most recent and comprehensive examples of a permeable surface installation is the Chicago White Sox stadium, U.S. Cellular Field, which includes roughly 265,000 square feet of permeable paving, completed in 2008.
The up-front cost for pavers (concrete or recycled plastic) is higher than a traditional asphalt installation. Generally, permeable driveway or parking lot requires slightly more maintenance (mowing, snow removal), yet there are considerable cost reductions when extensive underground drainage systems are eliminated, and the long-term environmental benefits should make it worth anyone’s consideration!
