| Publication | The integration of basin, streamflow and channel characteristics for channel condition analysis 11.7 MB PDF file by Orsborn et al. This report was prepared through a grant with Washington Trout using NW Forest Plan money. It evaluates the application of the "regional index of channel geometry" concept to assess stream channel condition. Stream channels reflect the cummulative effects of land uses with a given watershed, and therefore provide clues to how they balance flood flows and inputs of sediment and large woody debris. Land uses, such as timber harvesting, landslides, road construction and alteration of riparian zones associated with development, can significantly alter channel width, depth and gradient. How these channel components respond to changes in flow and sediment characteristics in large part determine the quality of salmon spawning and rearing habitats of rivers and streams of throughout the Pacific Northwest. To date, we have no reliable means to judge the "state" of channel dimensions from a regulatory perspective. The report attempts to address that need by examing the concept from a theoretical as well as a case study perspective.
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