ABSTRACT
Mostly used for walkways, trails, parking lots and low volume roads, porous pavements offer a process to manage storm water in an environmentally friendly way and are considered to be a multifunctional low impact development technology. In porous asphalt pavements (PAP) the subgrade is left uncompacted to maximize water infiltration. A geotextile fabric is placed between the subgrade and the stone recharge bed above it to prevent migration of fines from the subgrade to the storm recharge bed. A rooftop rainwater harvesting systems of the buildings adjacent to porous parking lots or streets can be integrated into the porous asphalt pavement. The water from the rooftop is carried directly to the stone water reservoir and dispersed there through a series of perforated water pipes. Hydrologic considerations for the design of PAP include layer thickness, subgrade permeability and precipitation intensity.
