What Are Impervious Surfaces and Why are They Important?

Impervious surfaces are any hardpacked surface (predominantly man-made) that impede the natural percolation of water from the surface of the terrestrial environment through the soil and substrate and into the groundwater. They prevent groundwater recharge and more importantly, significantly increase runoff.

Impervious surfaces alter the biota, ecology, hydrology, and overall environmental balance of a watershed.


What are considered impervious surfaces?