Data requirements for seasonal discharge programs: An application of a regionalized sensitivity analysis

Abstract

The design of seasonal water quality management programs that allow different waste discharge rates during different periods of the year may require reliable long‐term records of stream conditions. A modified regionalized sensitivity analysis (RSA) is applied for assessing the effect of unreliable stream records on the design of such programs. This approach is demonstrated for a seasonal waste discharge program that controls biochemical oxygen demand in a typical river basin. Here the uncertain input parameters include flow and temperature data at different times in the year and at different locations in the stream. An RSA is conducted for waste management scenarios that have different season length combinations and dissolved oxygen goals. Results indicate that the design of a seasonal waste discharge program for this case study is generally more sensitive to uncertainty in summer flow and temperature data than to uncertainty in winter data. Downstream flow data are shown to be more important than upstream data in low‐flow periods, while upstream flows are also important in high‐flow periods. In addition, the degree to which uncertain stream conditions affect the management model outcome depends on the water quality goals of the governing agency and the length of the seasons examined.

Comparing sensitivity analysis methods to advance lumped watershed model identification and evaluation

“…These sensitivity analysis methods were selected for comparison due to their popularity and their common application in a variety of scientific domains (Doherty, 2003;Doherty and Johnston, 2003;Moore and Doherty, 2005;Wagener et al, 2003;Lence and Takyi, 1992;Freer et al, 1996;Pappenberger et al, 2005;Mokhtari and Frey, 2005;Sobol', 1993Sobol', , 2001Fieberg and Jenkins, 2005;Hall et al, 2005). The sensitivity analysis methods tested in this study range from local to global and capture a broad range of analysis methodologies (differential analysis, RSA, and variancebased analysis).…”

“…RSA (Young, 1978;Hornberger and Spear, 1981) is also called generalized sensitivity analysis (GSA) (Freer et al, 1996) and has been widely used in hydrology (e.g., Lence and Takyi, 1992;Spear et al, 1994;Freer et al, 1996;Pappenberger et al, 2005;Sieber and Uhlenbrook, 2005;Ratto et al, 2006). Monte Carlo sampling and "behavioral/nonbehavioral" partitioning are the two major components of this method.…”

Global sensitivity analysis in hydrological modeling: Review of concepts, methods, theoretical framework, and applications

“…The larger the distance, the more sensitive the parameter is (Yang, 2011). RSA has been widely used in hydrological models (e.g., Lence and Takyi, 1992;Freer et al, 1996;Pappenberger et al, 2006;Sieber and Uhlenbrook, 2005;Ratto et al, 2007;Tang et al, 2007a;Pappenberger et al, 2008;Yang, 2011;Massmann and Holzmann, 2012). From these studies, we can see that its advantage is conceptually simple and easy to implement.…”

The uncertainty effects of design flow on water quality management

“…The uncertainty of design flow can be summarized as two parts: flow variability and calculation error. Flow variability has been discussed more than calculation error of design flow and has been well documented by hydrologists (Lence and Takyi 1992;Salas and Obeysekera 1992;Hakanson 1996;Kao and Bau 1996;Chaleeraktrakoon 1999;McCuen and Beighley 2003). Although the uncertainty related to other model parameters has received much concern and even sampling plans and management approaches have been designed to deal with the uncertainty, the uncertainty of design flow has rarely been discussed in water quality control policy.…”