184 SNAKE RIVER PLAINS OF IDAHO. [bull. 199. 
there is no evidence of the presence of an artesian basin. While the 
surface is essentially level, the few measurements of elevation avail- 
able indicate that there is a descent of approximately 25 feet to a mile 
from the region of Big Butte southwestward. Under favorable sub- 
surface conditions this would produce an artesian slope which might 
yield flowing water on drilling. 
The presence of such an artesian slope has been tested in part by 
wells along the line of the Oregon Short Line Railroad at Wapi (250 
feet), Minidoka (425 feet), and Kimama (325 feet), which fail to furnish 
flowing water, but yield a supply that is raised by pumping. 
As may be judged by the statements of probabilities made above, it 
is almost impossible to obtain data by means of which a judgment can 
be formed in reference to the chances of obtaining water in the region 
referred to. The evidence is negative and so far as it permits one to 
form an opinion does not favor the hope that flowing wells can be 
obtained. While there is but little if any hope of obtaining artesian 
water, it is probable that " rock wells," that is, wells in the solid rock 
but not flowing wells, drilled to a depth of from 300 to 500 feet, would 
reach water. As there is an immense tract of excellent grazing coun- 
try in this portion of the Snake River Plains, it is probable that it will 
be found practicable to establish cattle ranches there, the necessary 
water supply being obtained by pumping from rock wells. There is 
a report current among stockmen and sheep herders who visit the 
region lying southwest of Big Butte in winter to the effect that 
flowing water comes to the surface at one locality. This report is 
well worth investigating, for the reason that a single watering place 
in such an immense pasture would be of great value. 
COXCTATSION. 
My reconnaissance led to the following general conclusions in refer- 
ence to the future development of southern Idaho: 
1. The surface water supply at present available is largely wasted, 
and can by proper economy be made to yield two or three times the 
service now obtained from it. 
2. Every effort should be made to divert and utilize surface streams. 
In this connection, it is evident from the work of the State engineer 
and from personal inspection that it is practicable to use for irrigation 
the entire summer flow of all the streams reaching the Snake River 
Plains. 
3. The next largest source of water supply after the flow of the 
streams in summer has been fully employed is by means of storage 
reservoirs. The sites of such reservoirs have in part been indicated by 
the State engineer and the hydrographic division of the United States 
Geological Survey. 
4. Drill holes should be put down at the localities suggested on a 
