2006-06-12_REVISION - M1982015 (23)

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• • r1 L_J Page 1 of 3 T e of Channel and escri lion Minimum Normal Maximu A. Natural Streams 1. Main Channels a. Clean, straight, full, no rifts or deep pools 0.025 0.030 0.033 b. Same as above, but more stones and weeds 0.030 0.035 0.040 c. Clean, winding, some pools and shoals 0.033 0.040 0.045 d. Same as above, but some weeds and stones 0.035 0.045 0.050 e. Same as above, lower stages, more ineffective 0.040 0.048 0.055 slopes and sections f. Same as "d" but more stones 0.045 0.050 0.060 g. Sluggish reaches, weedy. deep pools 0.050 0.070 0.080 h. Very weedy reaches, deep pools, or floodways 0.070 0.100 0.150 with heavy stands of timber and brush 2. Flood Plains a. Pasture no brush 1. Short grass 0.025 0.030 0.03 2. High grass 0.030 0.035 0.050 b. Cultivated areas 1. No crop 0.020 0.030 0.040 2. Mature row crops 0.025 0.035 0.045 3. Mature field crops 0.030 0.040 0.050 c. Brush 1. Scattered brush, heavy weeds 0.035 0.050 0.070 2. Light brush and trees, in winter 0.035 0.050 0.060 3. Light brush and trees, in summer 0.040 0.060 0.080 4. Medium to dense brush, in winter 0.045 0.070 0.110 5. Medium to dense brush, in summer 0.070 0.100 0.160 d. Trees 1. Cleared land with tree stumps, no sprouts 0.030 0.040 0.050 2. Same as above, but heavy sprouts 0.050 0.060 0.080 3. Heavy stand of timber, few down trees, little 0.080 0.100 0.120 undergrowth, flow below branches 4. Same as above, but with flow into branches 0.100 0.120 0.160 5. Dense willows, summer, straight 0.110 0.150 0.200 3. Mountain Streams, no vegetation in channel, banks usually steep, with trees and brush on banks submerged a. Bottom: gravels, cobbles, and few boulders 0.030 0.040 0.050 b. Bottom: cobbles with large boulders 0.040 0.050 0.070 B. Lined or Built-U Channels 1. Concrete a. Trowel finish 0.011 0.013 0.015 b. Float Finish 0.013 0.015 0.016 c. Finished, with gravel bottom 0.015 0.017 0.020 d. Unfinished 0.014 0.017 0.020 e. Gunite, good section 0.016 0.019 0.023 f. Gunite, wavy section 0.018 0.022 0.025 file://C:\I IEC\I-IEC-RAS\3.1.3\HelpTable_Mann.htm Si. tlra,y Rr~Jrf /rla~'n ~~~~,~~e -orrae~ba,ak5 11 pT ;hiP/OU PO it X,i f,'~ La k..s r`ea~:~ ouei 6+r~ kS eF <_~ Jrc*~~+ F~;c1e f 4/24/2006