Use of Thematic Mapper data to update the land cover layer in a data base for electric power generation facilities.

The Pennsylvania Power and Light Company (PP&L) maintains a georeferenced Environmental and Land-Use Data System (ELUDS) for management and planning of electrical power generation and distribution facilities in central eastern Pennsylvania. The ORSER digital image processing system was used to perform preprocessing, analysis and display of the Landsat 4 digital data. Signatures for vegetation and land cover features were developed using a combination of unsupervised (CLUS) and supervised (STATS) techniques. A Euclidean distance classifier (CLASS) was applied to selected signatures to produce final classified maps. A modification of the DISPLAY program was developed to create hard copy map products at a scale of 1:24 000 on a Versatec 8222 electrostatic printer. A composite map was created using the classified maps with USGS 7-1/2 minute quadrangle mylar base maps. The composite maps were then compared to existing aerial photographs and ELUDS maps of land use, slope, and residential customer locations. -from Authors