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to average inflection point data. Method A was the mean of the inflection points <br />identified for each cross section. Method B was the inflection point of the means. <br />The six parameters are defined as: <br />a) Top width: width of the stream at the water surface. <br />b) Percent wetted perimeter: The distance along the stream bed in contact with <br />the water divided by the distance along the stream bed between the grassline <br />of each bank. <br />c) Depth: The vertical distance between the water surface and some point on <br />the streambed. <br />d) Rise in stage: The difference in the vertical distance from the water surface <br />elevation at a flow of 1 cfs to the water surface elevation at a higher flow. <br />e) Width/depth ratio: An index of cross - sectional shape, where top width is <br />divided by average depth. <br />f) Velocity: Distance water moves per second. <br />g) Bankfull stage: Discharge at which channel maintenance is the most <br />effective, that is, the discharge at which moving sediment, forming or <br />removing bars, forming or changing bends and meanders, and generally doing <br />work that results in the average morphologic characteristics of a channel <br />(Dunne and Leopold (1978). <br />The cross section analysis resulted in a description of channel morphology and the <br />inflection point analysis identified a flow where habitat parameters began to be impacted <br />at an increased rate. Stream wetted width was regarded as the most important of the six <br />variables, since changes in mean depths and velocities are related to the width. Riffles <br />were considered to be the habitat most vulnerable to impacts of low flows because of <br />their steeper gradients. Also since riffle habitats are required by macroinvertebrates and <br />10 <br />