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Mannings N: table 2
2. float finish to 2. planed, creosoted
Manning's n roughness coefficients for open channels and closed conduits — used in hydraulic flow calculations
| section | description | n max (dimensionless) | n min (dimensionless) | n normal (dimensionless) | subcategory |
|---|---|---|---|---|---|
| table 2 | 2. float finish | 0.016 | 0.013 | 0.015 | c. Concrete |
| table 2 | 2. grass, some weeds | 0.033 | 0.025 | 0.03 | b. Earth winding and sluggish |
| table 2 | 2. high grass | 0.05 | 0.03 | 0.035 | a. Pasture, no brush |
| table 2 | 2. in cement mortar | 0.018 | 0.012 | 0.015 | f. Brick |
| table 2 | 2. jagged and irregular | 0.05 | 0.035 | 0.04 | d. Rock cuts |
| table 2 | 2. light brush and trees, in winter | 0.06 | 0.035 | 0.05 | c. Brush |
| table 2 | 2. light brush on banks | 0.06 | 0.035 | 0.05 | c. Dragline-excavated or dredged |
| table 2 | 2. mature row crops | 0.045 | 0.025 | 0.035 | b. Cultivated areas |
| table 2 | 2. mortar | 0.015 | 0.011 | 0.013 | a. Cement |
| table 2 | 2. planed, creosoted | 0.015 | 0.011 | 0.012 | b. Wood |
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