Aspects & Impacts of Porous Pavements Essay -- Pavement Driving Surfac

Short Memo: Aspects & Impacts of Porous Pavements The purpose of this short memo is to discuss aspects of use, applicability, and environmental impacts of porous pavements as gleaned from practical findings and pertinent examples. A porous pavement is one with high enough porosity and permeability to allow rain and snowmelt to pass through it, thereby reducing the runoff from a site and surrounding areas. In intensely built up areas, pavements account for more than half of all the land, and for about two-thirds of total built cover (Ferguson, 2005, 2-3). Parking lots, in particular, account for the majority of paved areas. Pervious paving materials have the capability of providing a dual purpose in parking and other areas with low to moderate traffic; they serve both as a parking/traffic area and to manage stormwater. Components & Function There are several types of porous pavements, namely porous asphalt, porous concrete, and numerous modular paver systems. Both a construction material and a design technique, systems may be used individually or enhanced through a combination of types. Porous asphalt consists of an open-graded coarse aggregate bonded together by asphalt cement. The mixture contains fewer fines than traditional asphalt and sufficient void space between aggregate particles allows water to drain through quickly. Porous concrete also consists of an open-graded coarse aggregate, formulated with Portland cement and water. Modular porous pavers are structural units, such as concrete blocks or reinforced plastic mats, with void areas that are filled with pervious materials, to achieve a load-bearing permeable surface. The pervious fill materials include sand, grass turf, and gravel. Each of these surfaces is typical... ...rent purposes. Residential streets and interstate shoulders have been constructed of porous systems, and more extensive weight-bearing roads are functioning in Europe. More research and site study of porous paving techniques and specifications are needed to continue to increase knowledge and implementation of these systems, and to further their capacity for use. Works Cited Adams, Michele (May/June 2003). â€Å"Porous Asphalt Pavement With Recharge Beds,† Stormwater Magazine. www.forester.net/sw_0305_porous.html Ferguson, Bruce (2005). Porous Pavements. FL: CRC Press. Georgia Stormwater Management Manual (2001). â€Å"Porous Concrete.† Vol. 2, 3.3-33 - 3.3-40. Georgia Stormwater Management Manual (2001). â€Å"Modular Porous Paver Systems.† Vol. 2, 3.3-41 – 3.3-46. U.S. EPA (September 1999). Stormwater Technology Factsheet: Porous Pavement. Washington, DC: EPA 832-F-99-023.