35 
DRAINAGE OF IRRIGATED SHALE LAND. 
deep (Pl. VII, fig. 1), illustrates very clearly that a drain improp- 
erly located may be absolutely worthless, no matter how deep. The 
project is also interesting owing to the extreme rapidity with which 
the seepage trouble developed. In the season of 1913 about 4 acres 
near the center of the tract, upon which a young pear orchard was 
Herght of Ground Surface 
above Datum......——74— 
—_— 
\ 
SS 
of drainage. 
showing plan 
200 
tract near Canon City, Colo., 
Fig. 9.—Forty-acre 
growing and which was seeded to alfalfa, became so wet that the 
first crop of hay was harvested with difficulty. By midsummer 
water had risen to the surface of the ground and was running off 
through the irrigation furrows and waste ditches, and by late fall 
many of the pear trees and most of the alfalfa were dead (Pl. VII, 
fig. 2). 
