Mr. Justice Burnett
delivered the opinion of the court.
The Umatilla River is an unnavigable stream which takes its rise in the Blue Mountains near the eastern boundary of the county bearing its name, and, after receiving various affluents, flows in a general north to northwest course in passing the lands mentioned in this suit. The holdings of the plaintiffs are on the west side and premises of the defendants are on the east side of the river. After the fall rains have set in and until the melting snows of the mountains are gone in the early summer, there is enough water for all purposes; but by July the river gets low, and, until some time in September, there is a scarcity of water for late crops, such as the second and third crops of alfalfa, and not enough to operate defendants’ mill to its full capacity.
1. The pleadings cannot be construed into a suit to ascertain and declare the respective rights and priorities of the parties in the use of the waters of the river. The plaintiffs pray for the utter demolition of the defendants’ dam, so that the whole river may flow without hindrance to the intake of the Allen ditch; while the defendants, by the erection of a concrete dam entirely across the river *144above the diversion plant of plaintiffs, coupled with their avowed purpose to continue that policy, evidently intend to keep the water entirely away from the plaintiffs when their need is the sorest. In brief, each party wants all the water.
2. Both plaintiffs and defendants claim as appropriators, and not as riparian owners. The defendants argue that at the time the plaintiffs diverted the water in the first instance the stream was not one from which water could be appropriated, in the legal sense of the word, because the riparian ownership of the lands below the point of diversion had passed from the general government into private hands prior to the act of Congress of March 3, 1877, c. 107, 19 Stat. 377 (U. S. Comp. St. 1901, p. 1548), known as the “Desert Land Act,” and prior also to the diversion upon which plaintiffs found the inception of their claims. The defendants construe the act mentioned to mean that, whereas, before its enactment, appropriation could only be made where all the lands adversely affected were in the public domain, now, since its passage, the first appropriator may lawfully take the water of a stream, without regard to whether the lower riparian owners are private individuals or the general government; but that plaintiffs cannot claim the benefit of that act, because they diverted the water before its passage. But we think that neither the plaintiffs nor the defendants are in a position to raise this objection to appropriation as against each other, because none of them is a riparian owner, and the claim on both sides is that of appropriation. No one can claim both as a riparian owner and as an appropriator at the same time. While he may be one or the other of those characters, he cannot be both: Davis v. Chamberlain, 51 Or. 304 (98 Pac. 154). Some riparian owner defending or attacking as such might, in a proper case, raise that question, but no such party is before the court in this *145proceeding. We conclude that, as between the parties and on the record before us, the waters of the Umatilla River at all the times mentioned in the pleadings were the subject of appropriation in the legal sense of the word.
3. The plaintiffs assert title to the use of 1,080 inches of water, and offer as proof of that amount the decree of this court in the case of the Oregon Land & Construction Co. v. Allen Ditch Co., a plaintiff in this suit. The case is reported in 41 Or. 209 (69 Pac. 455: 93 Am. St. Rep. 701). The plaintiff there as a lower riparian proprietor sought to enjoin the Allen Ditch Company from diverting the water of the river in question away from the downstream lands of the plaintiff; but that suit was successfully defended on the ground that the defendant had acquired title by prescription to the use of 1,080 inches of water as against the plaintiff, having used the water adversely for more than ten years continuously. But the conclusion reached in that litigation bound only the parties to that suit, and hence cannot be used by the successful contestant there as evidence in its favor against the defendants here, who are strangers to that proceeding. Excluding that decree from the evidence here, as we ought, no definite testimony remains even as to the aggregate amount of water diverted or needed by the plaintiffs, much less as to the particular amount required or useful for the separate tracts owned by the several individual plaintiffs.
4. Equally indefinite is the testimony on behalf of the defendants relating to the actual amount of water originally appropriated by their predecessors in title to the mill property, or requisite for the purposes in contemplation at that time. In 1883, Mr. Koontz, the founder of the milling industry there, built a flouring mill having a capacity of 50 barrels every 24 hours. After it had been in operation for about two years, it was destroyed by fire, and he afterwards built a new mill with the *146enlarged capacity of 150 barrels per day, requiring greater water power. Machinery for manufacturing alfalfa meal has also been added to the milling plant since the first appropriation on the east side of the river.
The defendants seem to count upon the deeds from the former riparian owners to Koontz as giving the present owners of the mill unlimited and exclusive right to take the water of the stream in quantities ever increasing in proportion as their milling plant is enlarged, even to the diversion of the whole river into the millrace. We do not so construe the terms of those deeds, nor give them the effect desired by the defendants. The deeds conveyed to Koontz the right to divert from its natural channel and away from the land of the grantors, through the millrace, “such portions of the water of the Umatilla River as may be necessary for irrigating purposes along the line of said mill race and also to propel by water power any flouring or other mill which may hereafter be constructed by the said James H. Koontz, his heirs or assigns at or near the town of Echo.” This language of those deeds clearly indicates only a partial, and not a total, diversion of the stream as contemplated by the parties. It amounted to a license to the grantee to appropriate water sufficient for the enterprise then in view. He had the right to make one appropriation and to follow it up by actual application to the useful purpose designed within a reasonable time; but that would determine his right as of that date, if, indeed, it did not exhaust his privilege under that license. At any rate, each new enterprise or material enlargement of the old one requiring additional water would call for a new appropriation.
5. The parties to the deeds by their subsequent conduct put upon those writings a construction in consonance with the idea that the mill was to have only a part of the water. Without dispute, it appears in the testimony that *147after the mill had commenced operations its then owner, Mr. Koontz, joined with his grantors in those deeds, and other parties, plaintiffs’ predecessors, in building head gates and dams, and reconstructing the ditch now owned by plaintiffs, whereby the water was taken upon and made an appurtenance, not only to their lands, but also to his own land on the west side of the river, which he after-wards conveyed to plaintiff Andrews “with all the tenements, hereditaments or appurtenances thereunto belonging or any wise appertaining.” There was then water for users on both sides of the river. Mr. Koontz could not in equity and good conscience avail himself of the assistance of his then co-workers to reclaim his land and make the water appurtenant thereto, as well as to their holdings, and destroy the appurtenance after he had conveyed the land to one who bought on the faith of the then situation created by Koontz himself. His grantees stand in no better condition. They also took with knowledge of the situation as it then stood and were put upon their inquiry.
6. Before the country was so thickly settled at it is now, the practice for the appropriator of water “to keep all you get and get all you can” was in many cases tolerated; but, yielding to reason and justice to all, the later authorities have established a different rule. We conceive it to be the law, except as modified by statute, that the right of a prior appropriator is paramount, but the right is limited to such an amount of water as is reasonably necessary for such useful purpose and project as may be fairly within contemplation at the time the appropriation is made. Following the appropriation, the appropriator is entitled to a reasonable time within which, by ordinary diligence, he may complete the project and actually apply the water to the useful purpose intended. What is reasonable, both as to the amount of water and as to the time any given project may be completed, must *148depend upon the facts and circumstances of each particular case: Ison v. Sturgill, 57 Or. 109 (109 Pac. 579), and Porter v. Pettengill, 57 Or. 247 (110 Pac. 393), are instructive cases on these matters.
Under the principle already noticed that any material enlargement of an original project or the inauguration of a new enterprise requiring additional water would call for a new appropriation which must be in subordination to the rights of others as then existing, the testimony on the part of the plaintiffs is not clear as to the scope of the undertaking in which they and their predecessors in interest at first engaged. We are unable to determine whether either plaintiffs or defendants have merely carried out their original designs, or whether they have gone on into new and enlarged ventures, demanding more and more water, until, as appears by the pleadings, they both want all the water.
7. We are satisfied from the evidence that plaintiffs and their predecessors were using the water for domestic purposes, watering live stock and irrigating on the west side of the river, before the diversion of water to the mill on the east side; but to what extent, either in the aggregate or as to any particular tract, is not disclosed by the record before us. Both plaintiffs and defendants have devoted their energies in this litigation, in the main to the establishment of mere priorities, without reference to what is a reasonable amount of water to be used, or what amount was in fact appropriated in the first instance. Under such circumstances, while we are satisfied that all the parties have rights in the water as against their opponents here, the record does not furnish us sufficient data upon which to declare or to define those rights with that certainty necessary to support the extraordinary remedy of injunction. To authorize an injunction, the rights which it is designed to protect should be established with certainty, and to that end all persons *149interested in the thing about which the dispute has arisen should be brought before the court. This was done in Hough v. Porter, 51 Or. 318 (95 Pac. 732: 98 Pac. 1083: 102 Pac. 728), where Justice King points out the futility and waste of effort in attempting to settle such a controversy by piecemeal.
We conclude that the decree of the circuit court should be reversed and the suit dismissed without costs or disbursements to either party, and without prejudice to any other suit either may deem it advisable to institute concerning the matters in dispute.
Reversed : Suit Dismissed.