IMPROVED REGIONAL MAPPING OF DEVELOPED LAND FOR SURFACE WATER APPLICATIONS, NASHVILLE METROPOLITAN STATISTICAL AREA, TENNESSEE

Developed land in a 3.4 million acre region around Nashville, TN was mapped by combining Landsat and U.S Census Bureau data. Spectral characteristics, proximity to roads, population density, and employment density were used to classify land, and the amount of development within each class was estimated by interpreting land cover at 1,054 random points on digital orthophotos. This procedure showed that areas within 120 m of rural roads contain about 48% of all developed land in the region, and that urban areas comprising 8% of the map area contain the rest. In contrast, about 53% of developed land falls within agricultural (e.g., cropland) and natural (e.g., evergreen forest) classes on the National Land Cover Dataset in this region. Implications for impervious surface estimation and surface water quality are the focus of an ongoing investigation.