With most of the drainage infrastructure in place, positive impacts on stormwater management will be accomplished by retrofitting rather than only through new construction. Highways and roads (as well as parking lots) comprise at least 25% of all impervious surfaces, and this percentage is often higher in urbanized areas. As these pavements age, they see rehabilitation, and this presents opportunities for stormwater retrofitting. Therefore, meaningful reduction of stormwater volumes and pollutant mass loading from such pavements requires some outside-the-box thinking. Permeable pavement—either in the road, as parking lanes, or as road shoulders—presents an efficient method of treating and infiltrating runoff at its source.
Local road and state highway agencies have stormwater management requirements, and such systems are external to the pavements. The technical challenge lies in making the pavements themselves part of the drainage system especially as pavements are rebuilt, whether as highways or parking lots. This challenge is heightened when traditionally water has been directed away from pavements because it can damage pavement bases and underlying soils. Permeable pavements challenge that notion by managing the extent to which water enters a pavement base and soil subgrade.Adapting the full-depth permeable pavement shoulder and road design is the focus of a forum on August 22 from 8 to 9:30 a.m. at the StormCon conference in Denver, CO. This forum includes five panel members representing Environmental Protection Agency, departments of transportation, pavement industries, consulting firms, and academic institutions. Each panel member will discuss key technical and institutional challenges, and ideas to overcome them. We expect some out-of-the box, yet technically, feasible ideas. The panel will then open the forum for public discussion and exchange of ideas. We encourage all conference participants to join us for this timely and stimulating forum.