1998 Impervious Surface Data

Land Use/Land Cover and Impervious Surface

About Data Attributes

To compute the area represented by each percentage of impervious surface, a raster attribute was added in which the acreage of the class value was multiplied by the class value.

Hence, the acreage of a 1% impervious surface Class Value is 1% of the total surface area of that class. Specifically, areas were calculated using the following formulae:

· Acres = Histogram * 247.105

where Histogram is the total number of pixels in each class respectively 247.105 is a constant representing the number of acres contained within each 1000 m x 1000 m pixel.

· IS_acres = Acres * (Class_value/100)

· IS_hectares = Histogram * (Class_value)

Impervious Percentage

Impervious Acres

Acres with a portion IS