8 BULLETIN 913, U. S. DEPARTMENT OE AGRICULTURE. 



mentary and the physical evidence of the value of the right to be 

 purchased, giving, perhaps, more attention to the latter than to the 

 former. 



RIGHTS TO UNDERGROUND WATERS. 2 



Though most farmers who settle on irrigated land obtain rights 

 through organizations of some kind rather than direct from streams, 

 there is large opportunity for individuals to obtain independent sup- 

 plies of water from underground sources through wells. 



With relation to the nature of rights to their use, underground 

 waters are divided into four classes: (1) Underground streams 

 flowing in known and defined channels; (2) underground streams 

 flowing in unknown and undefined channels ; (3) artesian waters ; and 

 (4) percolating waters. While these classes are distinct in law, it is 

 not always easy to tell to which class a particular supply belongs. 

 In fact, water which has long been considered in one class may be 

 found to be in another class, and thus subject to a different law. 



Subterranean streams flowing in known and defined channels are 

 subject to the same laws as surface streams — that is, in most States, 

 to appropriation rights — and one may not take water from such 

 a stream by means of wells or other means if it interferes with the 

 rights of prior appropriators. Ownership of the land on which a 

 well is located does not give any right if the water is, in fact, a part 

 of the stream. 



But if a well draws water from an underground stream whose 

 channel is unknown and undefined, the ownership of land carries 

 with it the right to take the water. It is clear that the channel of 

 such a stream may become known as a result of investigation, in 

 which case the stream will become subject to the law of appropria- 

 tion, and the j^rior users may stop the use by later appropriators. 



Artesian water — that which is under pressure within the ground, 

 so that it will rise in the well to or toward the ground surface — is 

 held to belong to all the land overlying the artesian basin, and each 

 owner of such land is permitted to make any reasonable use of the 

 water which will not interfere with a like use by all the other land- 

 owners. In this respect rights to artesian waters are similar to 

 riparian rights on streams — they are not fixed and definite, but 

 depend upon the total supply and the total demand by all owners 

 of land overlying an artesian basin. Since the water is the common 

 property of many owners, it is subject to public control, and most 

 of the States have more or less legislation on the subject. 



Percolating water — that is, water moving through the soil, but not 

 under pressure and not confined to a known and defined channel — 



2 This discussion is based on Kinney's " Law of Irrigation and Water Rights," second 

 edition, San Francisco, 1912. 



