The Effects of Land Cover Change: Increasing Watershed Imperviousness in Kentucky - Geotechnologies and the Environment - page 111

Chapter 8
The Effects of Land Cover Change: Increasing
Watershed Imperviousness in Kentucky

Demetrio P. Zourarakis and Brian D. Lee

Abstract Imperviousness is recognized as a leading and trailing indicator of water-
shed health and one of critical importance in watershed management and planning.
Quantitative evidence points to a close correlation between the increase in imper-
viousness and temporal land cover change. Drawing from baseline and temporal
land cover change datasets generated for the state of Kentucky, U.S.A, this chap-
ter presents two examples of geotechnology usage: remote sensing and geographic
information systems (GIS) based modeling. Two methods are presented for calcu-
lating the increase in total impervious area (TIA) for a given watershed, by using a
baseline imperviousness dataset and updates to the spatial distribution of land cover
over time. Since as a spatial variable TIA can represent both categorical and contin-
uous variation, considerations regarding data handling methods (i.e. resampling) to
maintain original data accuracy while making the publically available data compati-
ble to existing and planned datasets are considered. TIA increase and its implications
for watersheds experiencing changes in urbanized areas, is explored in two temporal
directions; the first, retrospective, and the second prospective, or updating. Finally,
the potential consequences as a result of the findings are examined in the context of
their impact on watershed based policies and management with a specific example
relevant to an ongoing stormwater management conundrum.

Keywords Watershed imperviousness · Land cover · Change detection · Remote

sensing · Landsat · Reprojection · GIS