![]() Collectively, these maps can set bounds and provide realistic guidance for river rehabilitation, design and implementation efforts. Specifically, we (1) assessed river diversity (character and behavior) and patterns of reach types (and their controls) (2) evaluated the geomorphic condition of the streams (3) interpreted their geomorphic recovery potential and (4) synthesized the above into a hypothetical, strategic management plan. However, at the watershed scale, patterns derived from mapping confinement are not fundamentally different, making this a reasonably accurate and rapid technique for analysis and measurement of confinement across broad spatial extents.Ī geomorphic assessment of the Middle Fork John Day Watershed, Oregon, USA, was used to generate a hierarchical, map-based understanding of watershed impairments and potential opportunities for improvements. This is particularly important when differentiating rivers in the partly confined valley setting. Confinement accuracy can be improved (circa 4% to 17% gains) using a more accurately mapped valley bottom and channel position (i.e., with higher‐resolution model inputs). A sensitivity analysis found that a 500 m reach segmentation length produced reasonable agreement with manual, categorical, expert‐derived analysis of confinement. Comparison of manually digitized and mapped with modelled calculations of confinement revealed that roughly 1/3 of reaches were equivalent and about 2/3 of the sites differ by less than ☑5%. To test the reliability of calculating confinement across entire networks, we applied our geoprocessing scripts across four physiographically distinct watersheds of the Pacific Northwest, USA using freely available national datasets. The valley bottom is occupied by the contemporary floodplain and/or its channel(s) confining margins can be any landform or feature that makes up the valley bottom margin, such as bedrock hillslopes, terraces, fans, or anthropogenic features such as stopbanks or constructed levees. At the reach scale, valley bottom confinement is measured and quantified as the ratio of the length of channel confined on either bank by a confining margin divided by the reach length. Confinement is a useful metric for characterizing and discriminating valley setting. In this paper, we demonstrate the application of a continuous confinement metric across entire river networks. ![]()
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