Pervious Pavement

Pervious Pavement

We have all seen water from a recent rain shower that has pooled on a road or in the corner of the parking lot. We have all seen the oil slick or shinny substance on lot of that pool. But did you know that there is a pavement product out there called pervious pavement that can help with both of these problems? I am not only going to tell you what pervious pavement is, I am also going to talk about the benefits of pervious pavements. Though I am going to be focusing on concrete and asphalt, I will finish up with some of the different types and uses for pervious pavement. So let us start at the beginning with what pervious pavement is.

Pervious pavement is used in many applications ranging from paving roads and sidewalks to your back patio at your house. It is made of either pervious asphalt or pervious concrete and resembles conventional asphalt or concrete. The difference is the pervious material has more air spaces that allow water to pass through the pavement into a reservoir base of crushed aggregate, then infiltrate into the ground. This is accomplished by removing small stone and fine particulate matter and in the case of asphalt reducing the quantity of tar. By removing the small stone and fine particulate there are voids in the material that allow the water to pass through to the crushed aggregate base. Sealants to waterproof new surfaces are also not applied. In many cases standard paving machinery and equipment is used. As with any building material there are several benefits and disadvantages to using pervious pavement.

The environmental, economic, and structural benefits of the pervious pavement are many being recognized as a best practice by the U.S. Environmental Protection Agency. The environmental benefits are many providing a valuable stormwater management tool. The pervious pavement surface first allows the water to pass through recharging groundwater levels and then acts as a pollutant filter keeping many harmful substances such as automobile oil and antifreeze out of the stormwater systems. The economic advantage is in the overall life span of the project due to the fact that pervious asphalt and concrete on average costs 15-25% more than traditional materials. But studies are indicating the maintenance costs are less due to the fact that pervious material is less prone to cracking or buckling from freezing and thawing, and less frequent repair and patching. Another economic benefit is less need for an underground storm drain system or a gutter system. Requires less land set aside and cost in the development of runoff retention ponds or areas. The structural benefits as mentioned previously require less maintenance through the 20-40 year projected life span of the project. The permeable surface also provides increased safety for drivers reducing the night time glare of water on the surface and the risk of hydroplaning. There are many