NPR’s Living on Earth ran an interesting story this Saturday about porous pavements such as Ecocreto. In places where a good deal of the land surface area is made of impervious materials like regular concrete or pavement, rainwater can sometimes go unused, be discharged to the sea (think Los Angeles or Mexico City), and contribute to flash floods along the way. By absorbing the water and slowly releasing it, permeable concrete is designed to alleviate these issues.
Also available on their website is an interview [mp3] with Bruce K. Ferguson, director of the School of Enivironmental Design at the University of Georgia, on the same subject.The story was particularly interesting to me since I’m spending this summer outside of Baltimore in one of the “flashiest” (which has nothing to do with this) watersheds in the country, the Dead Run watershed. It literally takes minutes for any rain from summer thunderstorms to shoot through the tributaries and be discharged because of all the impervious surfaces.