Groundwater is a source of drinking water for many people worldwide. It also nourishes deep-rooted plants and trees. Replenished by rain and melting snow, groundwater has become an endangered resource, partly because of the impermeable materials used in new developments in and around cities and towns. Roofs, roadways and runways, parking lots, driveways, sidewalks, patios, and paved tennis courts prevent surface water from seeping into the ground.

You can do your part in addressing these problems by installing permeable materials when building patios, walkways, parking spaces, and driveways. There are many attractive options that will permit water to drain into the ground. Some even help reduce heat accumulation around buildings.

What Are Your Options?

For patios or walkways, consider installing permeable concrete pavers. The pavers themselves are solid, but if they’re spaced correctly, water drains between them. Pavers are placed over a bed of sand or gravel, which filters the water before it percolates into the soil. Permeable pavers come in several attractive styles and are made from concrete or cut stone.

When replacing or creating a new driveway or parking area, consider porous pavers or open-cell concrete blocks. These blocks are designed to support vehicles, but are sufficiently open to allow water to drain through them easily. The spaces are filled with gravel or sand. You can even grow grass in the open spaces, reducing heat buildup.

Another product that can be used for driveways is pervious concrete. As its name implies, this is a highly porous concrete. It is made from aggregate (small stones) and cement, which binds the aggregate together. However, unlike conventional concrete, pervious concrete contains very little, if any, sand. This results in a substantial void content.Pervious concrete is recommended by the US Environmental Protection Agency and geotechnical engineers across the country to help manage stormwater run-off.

What Will It Cost?

Porous and permeable paving products cost more than standard paving materials, such as asphalt and concrete, but they can add value to your project, when compared to asphalt or conventional concrete. Permeable paving is a green feature—and pavers can boost curb appeal.

Dan Chiras, Ph.D., author of this article, is Director of The Evergreen Institute and President of the consulting firm, Sustainable Systems Design, Inc. Dan is the author of Green Home Improvement, from which this article is excerpted, and 23 other books on green building, residential renewable energy, and sustainability.