Multi-site evaluation of hydrology component of SWAT in the coastal plain of southwest Georgia
Article first published online: 11 MAY 2012
Copyright © 2012 John Wiley & Sons, Ltd.
Volume 27, Issue 12, pages 1691–1700, 15 June 2013
How to Cite
Cho, J., Bosch, D., Vellidis, G., Lowrance, R. and Strickland, T. (2013), Multi-site evaluation of hydrology component of SWAT in the coastal plain of southwest Georgia. Hydrol. Process., 27: 1691–1700. doi: 10.1002/hyp.9341
- Issue published online: 4 JUN 2013
- Article first published online: 11 MAY 2012
- Accepted manuscript online: 17 APR 2012 06:24AM EST
- Manuscript Accepted: 10 APR 2012
- Manuscript Received: 22 JUL 2011
- multi-site evaluation;
- ungauged watershed;
- parameter extrapolation;
- spatial distribution;
Simulation of watershed scale hydrologic and water quality processes is important for watershed assessments. Proper characterization of the accuracy of these simulations, particularly in cases with limited observed data, is critical. The Soil & Water Assessment Tool (SWAT) is frequently used for watershed scale simulation. The accuracy of the model was assessed by extrapolating calibration results from a well studied Coastal Plain watershed in Southwest Georgia, USA, to watersheds within the same geographic region without further calibration. SWAT was calibrated and validated on a 16.7-km2 subwatershed within the Little River Experimental Watershed by varying six model parameters. The optimized parameter set was then applied to a watershed of similar land use and soils, a smaller watershed with different land use and soils and three larger watersheds within the same drainage system without further calibration. Simulation results with percent bias (PB) ±15% ≤ PB < ±25% and Nash–Sutcliffe efficiency (NSE) 0.50 < NSE ≤ 0.65 were considered to be satisfactory, whereas those with PB < ±10% and 0.75 < NSE ≤ 1.00 were considered very good. With these criteria, simulation results for the five non-calibration watersheds were satisfactory to very good. Differences across watersheds were attributed to differences in soils, land use, and surficial aquifer characteristics. These results indicate that SWAT can be a useful tool for predicting streamflow for ungauged watersheds with similar physical characteristics to the calibration watershed studied here and provide an indication of the accuracy of hydrologic simulations for ungauged watersheds. Copyright © 2012 John Wiley & Sons, Ltd.