ARS | Publication request: Assessment of Riparian Buffer Impacts Within the Little River Watershed in Georgia USA with the SWAT Model

Submitted to: Proceedings of the Watershed Technology Conference and Workshop, Improving Water Quality and the Environment
Publication Type: Proceedings
Publication Acceptance Date: December 15, 2009
Publication Date: February 21, 2010
Citation: Bosch, D.D., Cho, J., Lowrance, R.R., Vellidis, G., Strickland, T.C. 2010. Assessment of Riparian Buffer Impacts Within the Little River Watershed in Georgia USA with the SWAT Model. IN: Proceedings of the Watershed Technology, Improving Water Quality and Environment. 21st Century Watershed Technoogy: Improving Water Quality and the Environment Universidad EARTH, February 21-24, 2010, Costa Rica.

Technical Abstract: Computer based hydrologic and water quality models have proven to be useful tools for examining alternative management scenarios and their impact on the environment. This examination can be an important component of watershed-scale evaluations. The Soil and Water Assessment Tool (SWAT), is a watershed-scale model commonly used for these type evaluations. In many watersheds, riparian buffers play a dominant role in hydrologic and water quality functions. SWAT provides a simplified representation of these buffers. Simulations of riparian buffer processes within the Little River Experimental Watershed, Georgia were compared to observations made on the watershed. Long term observed trends in streamflow and sediment, nitrogen, and phosphorous in-stream loads were compared to simulated values and assessments of the impact of the buffers made. Accurate representations of streamflow were obtained for the watershed. Simulated monthly sediment and nutrient loads were within acceptable ranges. The watershed and buffer configuration were found to have a limited impact upon watershed hydrology, but a dramatic impact upon sediment and nutrient dynamics. Sediment and nutrient load simulations were found to be sensitive to selected critical source area and filter width within the model. This analysis provides guidance to more accurately determine watershed configurations and to represent riparian buffers within SWAT. Recommendations are made on optimum watershed and buffer configurations as a function of stream network.