26 GEOLOGY OF SW. IDAHO AND SE, OREGON. [bill. 217. 
stration. The reasons for predicting the presence of subsurface water 
under pressure are the basin-like structure the rocks exhibit and the 
presence within the basin of strong springs of warm water. The area 
throughout which it is probable that artesian water can be had is in 
the neighborhood of 20 square miles. 
The Harney artesian basin embraces the extensive region draining 
Malheur and Harney lakes, and as shown by its geological struc- 
ture may be expected to yield flowing wells throughout an area of 
perhaps 1,000 square miles. Two drill holes, one near Harney and 
the other near Burns, have been put down and have demonstrated 
the existence of subsurface water under sufficient pressure to force it 
to the surface where wells are drilled to the requisite depth and prop- 
erly cased. The artesian head, as indicated by these wells, has an 
elevation of about 4,100 feet. The thickness of rocks involved in the 
formation of the basin, however, probably exceeds 10,000 feet, and 
water-bearing horizons at a greater depth than those now known may 
reasonably be expected to be present. Several warm and hot springs in 
the Harney basin, as already mentioned, lend support to the prediction 
that success will follow a careful exploration of the basin with the drill 
where the surface elevation is less than that of Harney or Burns. 
The Whitehorse artesian basin is located about 20 or 25 miles east 
of the higher portion of Stein Mountain, and includes the valley in 
which the former military post known as Whitehorse was located. 
Here again the geological structure and the presence of warm springs 
are sufficiently strong indications to warrant a careful exploration 
with the drill witli the hope of obtaining a surface flow of water. The 
artesian head, as shown by the warm springs about 6 miles south of 
Whitehorse ranch, is well above the flat lands of the valley's bottom. 
The area throughout which one is seemingly justified in predicting 
success in case wells are drilled is not less than 30 square miles. 
The four artesian basins briefly described above contain about 2,000 
square miles of rich agricultural land, throughout which the condi- 
tions justify the opinion that flowing water may be obtained. It does 
not follow from this that all or even the greater part of the tracts 
referred to can be irrigated, as it is to be presumed that the water 
supply will not be adequate to meet all the demands that will be 
made upon it. The expense involved in drilling a well, and the 
certainty that the water supply even under the most sanguine 
expectations which may seem warrantable is not inexhaustible, make 
it imperative that there should be the strictest economy in the use 
of the water and rigid restrictions with reference to its waste. Sug- 
gestions in this direction have been offered in the Preliminary Report 
on Artesian Conditions, to which the reader is referred for a more 
detailed record of the facts available concerning the artesian basins 
of the region under review and the best means to be employed in the 
development and care of their water resources. 
