Permeable pavements allow water to pass through them to an underground storage area to help it infiltrate into the soil, unlike traditional impervious pavements that cause stormwater runoff. The top layer has openings that allow water to percolate to a gravel storage layer of variable thickness, which lets water infiltrate into the soil beneath. An underdrain system of perforated pipes allow water to flow out in the event of high influx.
Four different kinds of permeable pavements will be constructed and evaluated under the current project. These are grass pavers, interlocking block pavers, porous concrete, and porous asphalt. A newly constructed parking lot to serve the Texas Agrilife Center at Dallas will incorporate each of these pavements as well as one made of impervious concrete to serve as control.
Three parking stalls of each pavement will be replicated three times for a total of 45 experimental stalls. The parking stalls will include sub-grade and sub-base designs, and perforated pipes as recommended by the literature. The design will include provisions to hydrologically separate the varied parking stalls from each other.
The experimental parking stalls will be part of a larger parking lot intended to hold approximately 110 stalls. The remaining stalls will be constructed of pervious concrete. With the data collected from the experimental stalls, a representation of runoff and pollutant reduction will be estimated for the total parking lot.