2 2 LOSSES FROM CANALS BY SEEPAGE. 
action of the water and comparatively little washing takes 
place. In the course of years, however, the washing is suf- 
ficient to deepen the channel several feet below the sur- 
rounding country. As the water comes from a reservoir, it 
is clear except for the turbidity due to a slight amount of 
organic matter. The water retains its clearness for the 
greater length of the canal, but at the lower end contains 
some sediment from the scour of the channel. The soil is 
probably underlaid with sand and gravel at a depth of 8 or 
10 feet — true of most of the surrounding countrv — but no 
opportunity to test was afforded along this line. 
For the first three miles the seepage would be to the 
west; for the remainder of the distance it might take place 
both to the right and left of the channel. Some seepage 
showed near the northeast corner of section 8 where an 
area of a few acres gave evidence of water-logging. Be- 
cause of the sand carried by the rapid fall at the lower end, 
the space in front of the lower weir is filled with sediment. 
This increases the discharge by increasing the velocity of 
approach. Near the lower end of the canal a small lateral 
irrigating about lo acres of land conveyed water to the 
;north. When water was running in this lateral notes were 
laken and this time was not taken into account. 
