There may be, and there must be, of that which is common to all, a reasonable use. The true test of the principle and extent of the use is, whether it is to the injury of the other proprietors or not. There may be diminution in quantity, or a retardation or acceleration of the natural current, indispensable for the general and valuable use of the water, perfectly consistent with the use of the common right. The diminution, retardation, or acceleration, not positively and sensibly injurious, by diminishing the value of the common right, is an implied element in the right of using the stream at all. The law here, as in many other cases, acts with a reasonable reference to public convenience and general good, and is not betrayed into a narrow strictness, subversive of common use, nor into an extravagant looseness, which would destroy private rights. That of a thing common by nature, there may be an appropriation by general consent or grant. Mere priority of appropriation of running water, without such consent or grant, confers no exclusive right.
Plaintiff bought land and built a steam mill, which depends on the water for running the engine. Defendant then bought a mill downstream from Plaintiff's. At first there was enough water for both, but after a drought occurred, one of Plaintiff's employees made a dam across the water and diverted all the water into Plaintiff's well. As a consequence of this, Defendant's mill could not run. Defendant brought this suit as to the rights to the water.
Can riparian proprietors use as much water as they want from a stream on their land?
The Court held that without a contract or a grant, neither owner has a right to use all the water, because all have a right to participate in its benefits. Because of this, the upstream owner may only use as much as is necessary to satisfy his natural needs, and has to leave enough for the downstream owner's natural needs. This is because while manufactures promote the prosperity and comfort of mankind, it is not considered absolutely necessary to his existence, nor is the machinery which would be used from the water power.