Closure of "Theoretical Analysis of Wing Dike Impact on River Flood Stages"

In this article a response is given to a discussion on the article “Theoretical Analysis of Wing Dike Impact on River Flood Stages”. The discussers criticize the analytical approach in the original paper, repeatedly characterizing it as “oversimplified” and “simplistic.” However, The analytical approach was designed explicitly as a “simplified theoretical analysis,” and “a first step to better understand the connections between navigation structures and flood levels on the Middle Mississippi River (MMR).” Such calculations were needed in order to test the previous assertion, much repeated but based on presumed theory alone, that flood stage increases linked to wing-dike construction were “counterintuitive, and contrary to established models of hydraulic behavior” [U.S. Government Accountability Office (USGAO) 2011]. The investigation in the original paper indicates that wing dikes can increase flood levels, and that this effect can be understood from basic hydraulic theory. To accurately quantify flood level effects as related to wing dikes more rigorous follow-up studies are needed.