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55 chapter four Capital Conflicts I’d like to make this sound simple, but it’s not simple. It is doable, but you’re going to have to spend a lot of time in the field, in measurement and observation. —dr. david rosgen, Wildland Hydrology The simplest question about Natural Channel Design turns out to be the hardest to answer: does it work or not? Despite the fact that ncd has been in use since the mid-1980s, there is shockingly little solid evidence with which to answer that question. Instead, we have decades of claims and counterclaims. Critics have repeatedly raised a whole slate of objections to which ncd supporters respond with their own broken-record set of refutations. Critics argue that use of the ncd approach actually harms streams, while supporters say they use Rosgen’s restoration approach because it succeeds. They can’t both be right. Yet the debate has persisted with great intensity and no visible change in content for almost two decades, like some demented scientific version of the movie Groundhog Day. In this chapter I sort out the basic content of the debate. Because of the lack of definitive evidence, I draw on fluvial geomorphological theory, evaluations of restoration projects, and qualitative data to explain and assess ncd critics’ and supporters’ primary claims and to see whether we can in fact explain the vehemence of Rosgen’s critics on purely substantive grounds. the substance of the rosgen wars: claim versus counterclaim Rosgen’s opponents raise an exhaustive list of concerns about Rosgen’s classification system, design approach, recommended structures, and short courses as well as about his scientific practice and the scientific content of his work. This section attempts to explain and evaluate eight of the most common and substantive critiques.1 56 • chapter four Despite the fact that claims and counterclaims about ncd have preoccupied the stream restoration community since the mid-1990s, there are remarkably few data available to resolve the substantive issues I will describe below. In the years since Rosgen first published his classification system in 1994, no one has mounted the kind of broad-based study of project outcomes that might be capable of resolving the debate. The complexity of fluvial systems and the high level of uncertainty of restoration science make the production of such conclusive data a considerable challenge. At the most basic level, it is not clear how researchers would establish equivalency between projects in different watersheds and hydrophysiographic provinces. Establishing comparability between practitioners is another thorny issue, given the wide variety of paths people travel to become successful restoration practitioners. Simply determining criteria for success is also complicated, given that for Rosgen and his supporters a successful project does not move, while for his opponents the goal is a dynamic channel. For all of these reasons a definitive, geographically broad, comparative study of restoration approaches would be difficult to carry out, but it is surprising that neither Rosgen nor his critics have attempted such a study, and only one paper has even suggested it (Juracek and Fitzpatrick 2003).2 Good case studies could provide useful, if not definitive, data. But here, too, we come up short. While critics have conducted powerful case studies of particular restoration projects (most notably, Soar 2000; Kondolf, Smeltzer, and Railsback 2001; and Smith and Prestegaard 2005), these studies have at best limited relevance, as the designers of the projects reviewed did not follow anything near the complete ncd approach. Rosgen’s supporters, for their part, have not conducted the type of detailed , published case studies necessary to meet scientific standards of evidence . Instead, they refute their critics with nearly twenty years of anecdotal evidence about ncd projects, typically claiming success rates of 80 percent and above.3 Given that Rosgen’s supporters are just as committed to healing riparian systems as their critics, their claims for project success should not be dismissed out of hand. Indeed, some of them are very convincing. For example, Buck Engineering (now a subsidiary of Michael Baker Corporation), a North Carolina firm with extensive experience implementing ncd projects, offers clients warranties on their projects that cover the costs of repairing or replacing any structure that moves for a set number of years after project completion. Those warranties are a net source of revenue for the company: once in place, the Rosgen structures Buck Engineering installs rarely move.4 Still, the informal presentation of these and other claims limits their plausibility with Rosgen’s critics. Without...

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