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Table 1-5.7 "n" and "k" Values Used in Time Calculations for Hydrographs <br />Flow (initia1300 feet of travel) <br />Surface <br />Smooth surfaces (concrete, asphalt, gavel, compacted soil) <br />Fallow fields or loose soil <br />Short prairie grass and lawns <br />Dense grasses <br />IIermuda grass <br />Range (natural) <br />Woods or forest with light underbrush <br />Woc6s or forest with dense underbrush <br />Shallow Concentr'ed Flow (After the initia1300 teet of sheet llow; R= 0.1) <br />Surface <br />Forest with heavy ground litter and meadows (n = 0.10) <br />Brushy ground with some trees (n = 0.060) <br />Faflow or minirtum tillage cultivation (n = 0.040) <br />High grass (n = 0.035) <br />Short grass, pasture and lawns (n = Q.030) <br />Nearly bare ground (n = 0.25) <br />Paved and gravelareas(n = 0.012) <br />Intermittent Chunnel Flow (At the beginning ot visible channels, R= 0.2) • <br />Channel TyFa <br />Forested swale with heavy ground litter (n = 0.10) <br />Forested drainage course/ravine with defined channel bed (n = 0.050) <br />Rock-lined waterway (n = 0.035) <br />�rassed waterway (n = 0.030) <br />Earth-lined watenvay (n = 0.025) <br />CIviP pipe (n = 0.024) <br />ConcretP pipe (n = 0.012) <br />Other watenvays and pipe <br />Coatinuous Stream Channel Flow (R = 0.4) <br />Channel Type <br />Meandering stream with some pools (n = 0.040) <br />Rock-lined stream (n = 0.035) <br />Grass-lined stream (n = 0.0301 <br />Other strcams, man-made channels, and pipe <br />1-5-34 <br />n <br />0.011 <br />0.05 <br />0.17 <br />0.15 <br />0.24 <br />0.41 <br />0.13 <br />0.40 <br />k <br />3 <br />5 <br />8 <br />9 <br />11 <br />]3 <br />27 <br />k <br />5 <br />10 <br />15 <br />17 <br />20 <br />21 <br />42 <br />0.508/n <br />k <br />20 <br />23 <br />27 <br />0.807/n <br />C <br />� <br />l <br />