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On February 13, 2008, representatives from the Planning Department (2), Erosion Control (2), Inspections (1), Purchasing (1), and the County Manager's Office (1) met with a private resident to listen to a teleconference on practical applications of pervious pavement. Attached is a copy of the PowerPoint presentation from the February 13th session. While pervious pavement can take many forms, the example presented was a "no-fines" concrete. The material, when poured in place, resembles a Rice Krispies treat. The material has 15 to 25% void space with a porosity ranging from 150 to 400 inches per hour. The pervious pavement can be used in residential situations for driveways, sidewalks, and patios, and in commercial, industrial, and institutional applications as sidewalks, trails, sports courts in combination with plastic grids, parking surfaces, drive aisles, and roadways. For parking lot drive aisles and roadways, pervious pavement requires additional material strength. Increasing material strength reduces porosity. With a granular sub-base and a stormwater collection system, pervious concrete paving can provide innovative approaches to low-impact designs for residential and commercial development. The application can be cost effective and may result in more ecologically sensitive development. Issue: The North Carolina Department of Environment and Natural Resources (NCDENR) does not recognize typical pervious concrete pavement as a viable method to treat stormwater quantity and quality in the Piedmont region. The fine particles that make up the majority of Piedmont soils do not allow the stormwater that passes through pervious pavement to readily infiltrate into the ground. Additionally, fine particle sediment can clog permeable pavement if not maintained correctly. Therefore, porous pavement may still be considered impervious by NCDENR because of the nature of the tight clay soils found throughout Orange County. However, even with clay soils, pervious pavement can have benefits if engineered with a collection system below the pavement. Using pervious pavement in this manner may reduce the size or amount of stormwater management facilities required and can filter out many solid materials and pollutants suspended in stormwater runoff typically found in the "first flush" of any stormwater event. Oils and greases, heavy metals, sediments, fertilizers, and air-borne deposits typically pollute stormwater. With pervious pavement, the rainwater is spread more evenly over the entire parking lot and stormwater percolates through interconnected voids, rather than concentrating runoff into a pond. The presenter claims a 90% suspended solid removal from pervious concrete. The pervious concrete surface has good skid resistance and is easy to maintain. The surface is lighter in color and reflects sunlight better than a typical asphalt surface. This factor addresses the "heat island" effect of large asphalt parking lots. Pervious concrete paving can meet the US Green Building Council's Leadership in Energy and Environmental Design (LEED) standards because it can reduce stormwater runoff, it is composed of recycled materials, it can use regional materials, and it addresses urban heat island effects. Pervious concrete is five to ten percent more expensive per cubic feet than conventional paving; however, installation costs less because smaller crews are needed and the equipment is less costly. Further, site costs can be less because stormwater treatment facilities can be smaller. Tight Orange County clay soils do not allow credit for pervious paving. The watershed impervious cover standards do not need to change. However, pervious paving could be a key