How Well Do the Rosgen Classification and Associated ''Natural Channel Design'' Methods Integrate and Quantify Fluvial Processes and Channel Response?

ZeroFlow: A PUB (Prediction in Ungauged Basins) Workshop on Temporary Streams Summary of Workshop Discussions and Future Directions

“…Rosgen (1994) produced a classification system for natural streams based on morphological arrangement that perhaps could be adapted to the Canadian context. However, others have criticized that system (Miller and Ritter, 1996;Simon et al, 2005). Building on the notion that the river classification organizes data on stream features into discrete combinations (Rosgen, 1994), a number of approaches were proposed at the workshop.…”

Reply to Discussion1 by Dave Rosgen2

“…A focus on the true limitations of any method…may lead to improvements in design and application…Critical review and discussion can only improve the methods …” (Rosgen, 2006b). In response to criticisms that the NCD approach largely ignores the process dynamics of unstable stream systems (Simon et al. , 2005), Rosgen writes that the authors were essentially unqualified to make such a judgment because “ A two‐week course is required to teach professionals (including individuals who have graduated from college with advanced degrees in engineering, geology, hydrology, fisheries, etc.)…”

“… Multiple stream‐type succession end points for a given initial type (Miller and Ritter, 1996; Simon et al. , 2005, 2007).…”

“…, 2007). Inability to predict stable morphologies within a currently unstable system (Miller and Ritter, 1996; Juracek and Fitzpatrick, 2003; Simon et al. , 2005, 2007).…”

“…, 2008). Mixing of bed and bank‐material properties (Kuhnle and Simon, 2000; Simon et al. , 2005, 2007).…”