Impervious Surface Areas

Impervious surfaces are those areas which prevent or impede the infiltration and absorption of water into the soil. These surfaces are typically artificial structures such as roads and pavements that include but are not limited to rooftops, concrete, asphalt sidewalks, walkways, patio areas, driveways, parking lots or storage areas and gravel. As water travels over these impervious surfaces, it picks up many types of pollutants in the process carrying them into nearby storm drains and waterways.

The size and area of these impervious surfaces are used by the Department of Public Utilities to determine the Stormwater Utility rate for each property. The Impervious Surface Map

Impervious Surface (arcgis.com)