Assessing the Impact of Land Use Practices on Water Quality in the Kentucky River Drainage Basin

Recently, many publications have explored the utility of Geographic Information Systems (GIS) and remote-sensed imagery to approximate the regional causes of water pollution (Basnyat 1999; Basnyat 2000; Griffith 2002). In such studies, water pollution data is placed in a geographic context to see what generalizations can be made about the impact of regional land use practices on water quality. Such findings can be useful in the remediation of impaired watersheds, and in identifying unexamined watersheds with a high risk of impairment. These methods are particularly useful in evaluating the causes of non-point source (NPS) pollution, where the sources of pollution are diffuse and dependent on the health of an entire watershed. Of the nearly 200 waterways in the Kentucky River Watershed assessed by the Kentucky Division of Water, approximately half are considered "impaired", as documented in the 2002 303(d) report. The types of pollution responsible for these designations vary, with the most common impacts represented by organic enrichment, pathogens, nutrient loading, siltation, habitat modification and flow alterations. By framing these instances of pollution in the context of the land use practices in the immediate vicinity, we may find trends to point us in the direction of sustainable land management practices. Though studies in other regions have already demonstrated connections between some of these impact types and regional land use practices, it is imperative that these studies be widely repeated in multiple areas. This will allow policy makers and scientists alike to determine how universal, or case-specific, land management policies must be in order to preserve the integrity of freshwater resources. Combining previously collected water pollution data, land use coverages and watershed boundaries in a GIS interface, this study aims to see what connections between land use and water pollution can be demonstrated for the Kentucky River Drainage Basin.