Impervious surface means those disturbed or hard-surfaced areas that either prevent or restrict the natural entry of water into the soil. Rooftops, buildings, streets, parking lots, sidewalks, asphalt, concrete, other paving, driveways, gravel, patios, artificial turf, and storage areas are all examples of impervious surfaces. Impervious areas affect natural infiltration, creates more runoff, increases the rate of runoff, and alters runoff patterns of stormwater that drains from an area.