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<br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />I. N-VALUE SELECTION FACTORS <br /> <br />FACTOR <br /> <br />EFFECT <br /> <br />1. SURFACE ROUGHNESS <br /> <br />Increasing the size of the grains <br />of the material forming the <br />wetted perimeter generally <br />increases the n-values. <br /> <br />2. VEGETATION <br /> <br />Increasing the height and density <br />of the vegetation increases the <br />n-values. <br /> <br />3. CHANNEL IRREGULARITY <br /> <br />Abrupt irregularities in cross <br /> <br />section size and shape increases <br /> <br />the n-values. <br /> <br />4. CHANNEL ALIGNMENT <br /> <br />Sharp bends and severe meandering <br />increases the n-values. <br /> <br />5. OBSTRUCTIONS <br /> <br />Items that block the flow <br />log jams and bridge <br />increase the n-values. <br /> <br />such as <br /> <br />piers <br /> <br />6. STAGE <br /> <br />N-values generally decrease with <br />increasing depth. <br /> <br />7. SEASONAL CHANGE <br /> <br />N-values were selected for normal <br />maximum height and density of <br />vegetation during the flooding <br />season. <br />