Estimation of Daily Streamflow of Southeastern Coastal Plain Watersheds by Combining Estimated Magnitude and Sequence

Abstract

Commonly used methods to predict streamflow at ungauged watersheds implicitly predict streamflow magnitude and temporal sequence concurrently. An alternative approach that has not been fully explored is the conceptualization of streamflow as a composite of two separable components of magnitude and sequence, where each component is estimated separately and then combined. Magnitude is modeled using the flow duration curve (FDC), whereas sequence is modeled by transferring streamflow sequence of gauged watershed(s). This study tests the applicability of the approach on watersheds ranging in size from about 25‐7,226 km2 in Southeastern Coastal Plain (U.S.) with substantial surface storage of wetlands. A 19‐point regionalized FDC is developed to estimate streamflow magnitude using the three most selected variables (drainage area, hydrologic soil index, and maximum 24‐h precipitation with a recurrence interval of 100 years) by a greedy‐heuristic search process. The results of validation on four watersheds (Trent River, North Carolina: 02092500; Satilla River, Georgia: 02226500; Black River, South Carolina: 02136000; and Coosawhatchie River, South Carolina: 02176500) yielded Nash‐Sutcliffe efficiency values of 0.86‐0.98 for the predicted magnitude and 0.09‐0.84 for the predicted daily streamflow over a simulation period of 1960‐2010. The prediction accuracy of the method on two headwater watersheds at Santee Experimental Forest in coastal South Carolina was weak, but comparable to simulations by MIKE‐SHE.

Organized variability of surface runoff responses across neighboring hillslopes in Iowa

“…At the large scale (i.e., the catchment scale ranging from tens to thousands of square kilometers), hydrologic similarity between neighboring catchments has been frequently used for many purposes. Many studies use this idea for regionalization of models and parameters (e.g., Merz and Blöschl, 2004;Oudin et al, 2008Oudin et al, , 2010; some use this concept to predict streamflows for ungauged basins (e.g., Hirsch, 1979;Hortness, 2006;Archfield and Vogel, 2010;Ssegane et al, 2013); and others use it for creating hydrologic models (Andréassian et al, 2012). At the extreme case of small scale, i.e., the grid scale, the widely applied TOPMODEL assumes that all locations within the catchment that have the same topographic index respond similarly to similar inputs.…”

Application of LiDAR Data for Hydrologic Assessments of Low-Gradient Coastal Watershed Drainage Characteristics

“…and engineering designs for water resources structures involving Rational Method (Equation (1)), USGS regional flood discharge formula (Equation (2)) [55], peak discharge estimates (Equation (3)) [56], pollutant export coefficients, estimating flow rates using empirical approaches for ungauged basins (Equation (4)) [57], designing the best management practices, and nutrient loading estimates (Equation (5)) [58,59] generally used in Total Maximum Daily Load (TMDL) developments. …”

A functional framework for flow-duration-curve and daily streamflow estimation at ungauged sites

“…Once the FDC is estimated at the ungauged site, it may be incorporated into a transfer procedure through which the daily streamflow series is obtained (e.g. Mohamoud 2008;Ssegane et al 2013).…”

“…Over the literature, many studies presented and evaluated methods for estimating FDC at ungauged sites (e.g. Castellarin et al 2007;Mendicino and Senatore 2013;Li et al 2010;Ssegane et al 2013;Zhang et al 2015). According to Castellarin et al (2004), these methods may be classified into: i) statistical approaches based on probability distributions (e.g Fennessey and Vogel 1990); ii) parametric approaches based on analytical expressions (e.g.…”