bussell.] SURFACE STREAMS. 161 
reached, since water above a certain definite quantity skillfully applied 
is injurious to crops, and brings about cumulative difficulties in the 
way of concentrating" alkaline salts in the soils. 
Second. The canals and ditches, and in fact the entire practice of 
irrigation, should be under the control of a skilled and efficient engi- 
neer, in order that water ma} r be applied to the best land in proper 
quantity, all of the available supply utilized, and loss by evaporation 
and seepage reduced to a minimum. 
These conclusions, although sufficiently obvious in the abstract, 
become painfully apparent to one traveling through even the most 
productive portion of southern Idaho. It is safe to say that less than 
one-half of the service is obtained that the waters now flowing through 
canals and ditches might render under skillful management. Waste is 
everywhere conspicuous. The ignorance, carelessness, and greed of 
the people are disheartening to one who endeavors to point out addi- 
tional sources of water supply. Obviously the first and paramount 
duty of the people, not only in Idaho, but generally throughout the 
arid regions, is to employ economically the water now available in 
surface streams. 
An increase in the supply of water flowing through surface streams 
during the growing season, as has been pointed out by Ross and others, 
may be had by storing the water which runs to waste between the 
seasons when it is needed for irrigation. It is in this direction that 
the greatest addition to the amount obtainable by diverting streams is 
to be expected. For this purpose suitable reservoir sites must be 
available, situated where they can be filled during the winter season, 
and where desirable land exists at lower levels over which the water 
can be spread. This again is an engineering problem of high order, 
and one beset with difficulties and dangers. Some attempts have 
already been made in the direction of storing the winter flow of the 
streams, but not always wisely or well, and much more is to be expected. 
The cost of such enterprises is usually great, and it is evident that 
many favorable plans will have to wait until increase in population 
and greater demand for farm products justify the large initial expense. 
When all of the water furnished by streams during the growing 
season has been judiciously applied in irrigation, and all of the flood 
water that it is practicable to store in reservoirs is made available, 
there will still remain extensive tracts of excellent agricultural land 
unprovided for. Besides the need of water for irrigation, there is a 
great and constantly increasing demand for water for town and house- 
hold purposes. With the hope of supplementing the surface supply 
attention has been directed to subsurface waters. The chief purpose 
of the reconnaissance here reported on was to ascertain, so far as the time 
available would permit, what can be expected from this source. The 
Bull. 199—02 11 
