Assessment of two Carolina watersheds using land and stream habitat quality indices

ABSTRACT:

The US Department of Agriculture (USDA) Natural Resources Conservation Service (NRCS) has been directed to assist local landowners and communities to implement watershed improvement practices. The purpose of this study was to document current conditions in the Rocky River Watershed in North Carolina and the Saluda River Watershed in South Carolina. A variety of watershed assessment tools, including the NRCS Visual Stream Assessment (VSA), Stream Habitat Assessment (SHA), Riparian Vegetation Index (RVI), Index of Biotic Integrity (IBI), and Land Quality Index (LQI) were used on a statistically representative portion of both watersheds. Overall, the SHA, VSA, and RVI rated the watersheds' condition as good, whereas the IBI rated them as fair. Correlations between IBI and the other indices were poor, perhaps indicating these indices measure different features within the watersheds. The LQI emphasized the need for better characterization of urban Land and riparian corridors. Inclusion of suburban lawns with the urban land indicator improved correlations between IBI and LQI by 20%. This pilot study suggests further scrutiny in applying quantitative stream physical habitat measures to assess watershed conditions. It also indicates additional study of the IBI by NRCS. Resources devoted to statistical design were valuable and should provide the NRCS with a framework for conducting future watershed studies.