Porous asphalt looks and acts much the same as traditional asphalt with one difference. Porous Asphalt allows the water to drain through it at up to 100 inches per hour, making it able to withstand the inflow from the largest of storms. It is typically placed over an open graded base aggregate that is designed to collect the storm water and hold it in a reservoir below the asphalt surface where it slowly filters back through the soils and into the Earth’s aquifer. This can be a very useful application in many commercial projects where drainage is a potential problem or storm systems are prohibitively costly. This is also environmentally friendly as it reduces or eliminates surface runoff into stream and rivers as the storm water is retained and treated naturally on site by filtering through the soil, as nature intended.