Author(s): M. Pourreza-Bilondi; S. Zahra Samadi
Linked Author(s):
Keywords: Uncertainty Analysis; GLUE; HEC-HMS; Coastal Plain Watershed
Abstract: This paper examines the effects of hydrologic model parameterization uncertainty, where multiple unique hydrologic model parameters sets can result in adequate calibration metrics, on hydrologic modeling of the Waccamaw watershed (3116 km 2). HEC-HMS is linked to the generalized likelihood uncertainty estimation (GLUE) and is calibrated for daily streamflow at two USGS gauging stations during 2003–2005 period. A standard conceptual HEC-HMS's soil moisture accounting (SMA) approach is applied in this study that represents a sub-basin with well-linked storage layers/buckets accounting for canopy interception, surface depression storage, infiltration, evapotranspiration, as well as soil water and groundwater percolation. Analysis demonstrated that 95 prediction uncertainty bracketed most high and medium flows while slightly overestimated the magnitude and direction of low flow events. Since a large portion of the runoff-producing in the coastal plain watershed is groundwater dependent, hydrologic model parameterization may lead to statistically significant differences in streamflow prediction during different timescales.
Year: 2016