Impervious Surface (English)
Superficio impermeable (Español)
Surfaces imperméables (Français)
Impervious surfaces are mainly artificial structures--such as pavements (roads, sidewalks, driveways and parking lots) that are covered by impenetrable materials such as asphalt, concrete, brick, and stone--and rooftops. Soils compacted by urban development are also highly impervious. Impervious surfaces prevent water and rainfall from absorbing into the ground naturally, causing the water to flow off the ground in the form of urban runoff or stormwater.