When the Kentucky Transportation Cabinet (KTC) in 1999 unveiled possible routes for the section of Interstate 66 between London and Somerset, Kentucky, karst researchers became concerned. This proposed corridor traversed undeveloped woodlands inside and outside the Daniel Boone National Forest, crossed several high-quality watersheds, and threatened severe damage to cave and karst resources. In response, the I-66 Special Project of the National Speleological Society (NSS) in cooperation with the Sloans Valley Conservation Task Force, Kentucky Heartwood, Somerset Pulaski County Concerned Citizens, and dozens of other organizations initiated an extensive and cooperative karst data gathering campaign in the region.

The effort focused on collecting, maintaining, and presenting a GIS of karst resources in Pulaski County, Kentucky, using ArcView software. The first level of data included a point location database of cave entrances and associated karst features provided by locals and members of the caving community. A second layer of information included scanned and georeferenced (registered to real-world coordinates) cave maps. From these raster images, polygons outlining the passages were digitized to display regions in which surveyed caves were known to lie underneath the surface. A third layer of information included sinkhole polygons digitized from depression contours on 7.5-minute topographic quadrangles. The final layer of information in the GIS was vector representations of the corridor alternatives for the I-66 Special Project. This information was provided by KTC. All data was created using NAD83 datum and the Kentucky State Plane South 1983 coordinate system.

The data developed by this effort was used in several ways. Overlays of the corridor alternatives with a 1,000-foot buffer combined with conduit polygons, sinkholes, and cave entrance data were used to determine potential karst impacts for each alternative. Conduit polygons and sinkhole coverages for the area affected by the proposed corridors were provided to KTC and its consultants for incorporation in a second planning study (released in June 2000) to address the concerns raised by the first. Images produced using the data were presented in publications and at various presentations throughout the region to help others understand the concerns.

An example of one of the issues that KSS is addressing arose during the work in Pulaski County for the I-66 efforts. The interstate development problem illuminated the need for a detailed statewide sinkhole delineation. Following a review of the results of the I-66 Special Project, NSS, and considering the ongoing groundwater investigations occurring at the Kentucky Geological Survey (KGS), a decision was made to complete a sinkhole digitizing effort for all of Kentucky on a 1:24,000 scale.

The sinkhole digitization required that several data issues be addressed. These included the representation of complex uvalas (sinkholes with multiple sink points), differences in contour intervals between topographic quadrangles and their effects on data resolution, and manipulation of United States Geological Survey hypsography files.

The statistics generated by the KSS sinkhole digitization project are impressive. Nearing completion, more than 62,000 sinkholes have been digitized to date for Kentucky. The combined area of these polygons suggests that approximately 3 percent (more than 1,200 square miles) of the surface of Kentucky lies within a topographically mapped sinkhole. The sinkhole digitization effort has also helped KGS develop more effective dye tracing methods due to the recognition of regional sinkhole lineaments.

The completed statewide sinkhole coverage will be published through KSS and KGS and will include a descriptive folio and data CD-ROM. The coverage will be useful for many purposes including planning, resource management, cave and karst research, groundwater studies, and statistical analysis.