32 BULLETIN 852, U. S. DEPARTMENT OF AGRICULTURE. 



the foot of a low range of hills and delivering water to the intakes of 

 the cement-pipe laterals. This delivery consists of an iron head 

 gate at the canal end of a tube thro ugli the canal bank. Water is 

 discharged through the tube into a rectangular sand and pressure 

 regulating box 4 by 5 feet and 4h feet deep. 1 The water leaves this 

 concrete box over a weir crest and falls to the intake chamber of the 

 pipe line. At the head of lateral C the weir is of heavy sheet iron, 

 rectangular in form, 3.02 feet long, without immediate end con- 

 tractions, but with a bottom contraction of 39 inches. In addition 

 to the flow over the weir there was a small constant leak through the 

 drain gate near the bottom of the weir wall. This leak was measured 

 and added to the flow over the weir for any particular run of water. 

 A reach of pipe 1,116 feet long was chosen for test between a stand- 

 pipe located 99 feet from the intake and a division box. The pipe 

 was straight in horizontal alignment but wavy in the vertical plane, 

 having two summits, each protected by standpipes. At low points 

 of the profile the pipe is provided with blow-off valves. The maxi- 

 mum pressure on this pipe is due to a head of about 15 feet at the low 

 points. Water columns attached to piezometer tubes of type A 

 were used for both gauges. Tube No. 1 was dropped down a stand- 

 pipe and allowed to be carried 3 feet down the pipeline. Tube No. 2 

 was thrust 1 foot upstream into the pipe line from the wall of the 

 division box. The internal size of the pipe was determined by meas- 

 uring two diameters on each of 10 pipe units remaining from the 

 original construction. The mean area of these units was accepted 

 as the internal area of the pipe line. Each unit was 2 feet in length. 

 They were made by the " dry mixture" process and afterwards washed 

 with cement grout. The writer was informed that extreme haste 

 was used in laying the pipe and that the joints are very rough 

 internally. This would account for the heavy friction loss in this 

 pipe. Examination of both inlet and outlet indicated that this pipe 

 was free from gravel or other debris. At the time of these tests the 

 water was murky from recent rainstorms and the spring thaw, but 

 during most of the irrigation season the water is clear. The value 

 of C s is about 0.255. 



No. 17, Experiment $-46. — 20-inch jointed concrete pipe, Bishop 

 Literal, British Columbia Fruitlands Co., Kamloops, Britisn Columbia, 

 Canada. — Irrigation water is diverted from the main concrete-lined 

 canal by a tube through the canal bank, discharging into the sand 

 and weir box shown on Plate II, figure 1. From this weir the Bishop 

 lateral, an underground pipe line, leads down a steep hillside to a 

 point near the bank of Thompson River, thence paralleling the river. 

 A reach of pipe between a vertical air pipe and a turnout box was 

 chosen for experiment. The airpipe was located about three-eighths 

 mile from the weir shown in the plate, while the turnout was 

 777. 1 feet beyond the air pipe. Water columns attached to piezom- 

 eters of type A were used at both ends of the reach, No. 1 being set 4 

 feet down the pipe line from the air pipe and No. 2 being thrust 1.3 feet 

 upstream into the pipe line from the turnout. The pipe is gently 

 curving in horizontal alignment and appears to follow the river 

 grade in profile. If there is a sag in the profile it is too small to be 

 noticeable to the eye. Examination of the line when no water was 

 flowing showed the interior to be clean of deposit, but typically 



i Described in "Irrigation Practiceand Engineering," Vol. Ill, p. 368, B. A. Etcheverry, New York, 1916. 



