Paper No. JAWRA-10-0149-P of the Journal of the American Water Resources Association (JAWRA). Discussions are open until six months from print publication.
Incorporating Variable Source Area Hydrology into a Spatially Distributed Direct Runoff Model1
Version of Record online: 21 OCT 2011
© 2011 American Water Resources Association
JAWRA Journal of the American Water Resources Association
Volume 48, Issue 1, pages 43–60, February 2012
How to Cite
Buchanan, B., Easton, Z. M., Schneider, R. and Walter, M. T. (2012), Incorporating Variable Source Area Hydrology into a Spatially Distributed Direct Runoff Model. JAWRA Journal of the American Water Resources Association, 48: 43–60. doi: 10.1111/j.1752-1688.2011.00594.x
- Issue online: 1 FEB 2012
- Version of Record online: 21 OCT 2011
- Received September 14, 2010; accepted July 6, 2011.
- watershed management;
- open channel flow;
- surface water hydrology;
- surface/groundwater interactions
Buchanan, Brian, Zachary M. Easton, Rebecca Schneider, and M. Todd Walter, 2011. Incorporating Variable Source Area Hydrology Into a Spatially Distributed Direct Runoff Model. Journal of the American Water Resources Association (JAWRA) 48(1): 43-60. DOI: 10.1111/j.1752-1688.2011.00594.x
Abstract: Few hydrologic models simulate both variable source area (VSA) hydrology, and runoff-routing at high enough spatial resolutions to capture fine-scale hydrologic pathways connecting VSA to the stream network. This paper describes a geographic information system-based operational model that simulates the spatio-temporal dynamics of VSA runoff generation and distributed runoff-routing, including through complex artificial drainage networks. The model combines the Natural Resource Conservation Service’s Curve Number (CN) equation for estimating storm runoff with the topographic index concept for predicting the locations of VSA and a runoff-routing algorithm into a new spatially distributed direct hydrograph (SDDH) model (SDDH-VSA). Using a small agricultural watershed in central New York, SDDH-VSA results were compared to those from a SDDH model using the traditional land use assumptions for the CN (SDDH-CN). The SDDH-VSA model generally agreed better with observed discharge than the SDDH-CN model (average, Nash-Sutcliffe efficiency of 0.69 vs. 0.58, respectively) and resulted in more realistic spatial patterns of runoff-generating areas. The SDDH approach did not correctly capture the timing of runoff from small storms in dry periods. Despite this type of limitation, SDDH-VSA extends the applicability of the SDDH technique to VSA conditions, providing a basis for new tools to help identify critical management areas and assess water quality risks due to landscape alterations.