FLOW OF WATER IN IRRIGATION DITCHES 



239 



Group No. 2 

 w = o.oi94 to 0.0213 

 The cross-sections for this group were lacking in uniformity. The bed was usually of 

 small cobblestones or fine gravel. Some of the ditches had been in use thirty years. 



Character of Channel 



Clayey loam lined with sediment. Footprints of 

 stock. No vegetation 



Compact clay, some rock fragments. One side 

 smooth; willow roots projecting on other 

 side 



Clay covered with fine sand; $ of perimeter 

 covered with vegetation 



Small pebbles imbedded in sand 



No vegetation. Bottom smooth, composed of 

 fine gravel 



Bed smooth, free from vegetation, composed of 

 clayey loam 



Well-packed coarse gravel, weeds at edge 



Dis- 

 charge 



2 -5 



22.3 



23.6 



4.0 



0.6 



68.6 

 5i-4 



Area 

 Water 

 Section 



H-5 



21.8 

 4.0 



32.0 

 20.6 



Mean 

 Vel. 



1. 14 



I.94 



1.08 

 1 .00 



0-54 



2.14 

 2.49 



Slope 



. 00068 



. 00062 



.00015 

 .00056 



•00135 



. 00046 

 .00077 



.0194 



.0195 



.0197 

 .0201 



.0204 



.0211 

 .0213 



Group No. 3 

 M = o.o2i8 to 0.0238 

 The ditches in this group usually were designed for a greater flow than they were 

 carrying at the time of the experiments. 



Character of Channel 



Volume carried was small in proportion to 

 capacity. Clayey loam lined with sedi- 

 ment 



Partly full. Bed composed of well-packed 

 smooth gravel lined with sediment 



One-fourth full. Channel of clay; £ of peri- 

 meter covered with "frog moss" 



Well-packed gravel; lined with sediment; no 

 vegetation 



Clayey loam lined with sediment. Some "horse 

 tail moss " 



Same as above with no moss 



Partly full. Clayey loam; channel partly 

 stopped with irrigators' dams 



Fine gravel; no vegetation 



Dis- 

 charge 



87-3 



i-55 



3 2 



Area 

 Water 

 Section 



58.9 

 2.6 



Mean 

 Vel. 



O.61 



1. 19 



O.71 



1. 19 

 I.38 



I .01 

 1 .90 



Slope 



00027 



00040 



00020 



00043 



00075 

 00088 



00012 

 00175 



.0218 



•0223 



.0224 



.0229 



.0230 

 .0230 



.0232 

 .0238 



