This is an action to enjoin the appellants from diverting water from the South Fork of the American river at a point immediately above the dam of the respondent, and the principal question involved in the case may be stated as follows: If a prior appropriator of water constructs a dam across the bed of a stream for the purpose of raising its surface to a level which will cause it to flow into the head of his ditch, does he thereby acquire such an exclusive right in the bed and banks of the stream as far as the slack water extends above his dam that he can enjoin a subsequent appropriator of the surplus from tapping the stream, and diverting such surplus at any point above the dam and below the head of the slack water?
The decree of the superior court, from which the defendants appeal, cannot be sustained without affirming this proposition, as will clearly appear from a statement of the case.
The South Fork of the American river is a considerable stream heading in the high Sierras, and like other mountain streams varies greatly in volume from year to year, and from season to season. It reaches its lowest stage in each year towards the end of the dry season, and when the rains begin (usually in the fall) its flow increases in proportion to the amount of precipitation. Ordinarily it reaches its highest stages during the winter and early spring, at which period it is subject to heavy floods. After the rains cease in the spring its volume subsides, but its flow is maintained by the melting snows at a comparatively high stage until the latter part of the summer. These are features common to all the streams flowing from the Sierras to the Sacramento valley and are matters of universal notoriety. Such being the case, *44it is evident that an appropriation covering the entire flow of the stream at its lowest stages may leave a large surplus of water at flood, or even ordinary stages.
The plaintiff in this case in the year 1851 gave notice of its intention to divert and appropriate, for the purpose of placer mining and irrigation, enough of the waters of the South Fork to fill at all times a canal eight feet wide and four feet deep, with a current running ten miles per hour. In pursuance of this notice it proceeded to construct a canal ten or fifteen miles in length, but not of the capacity mentioned in its notice. Its present capacity, as found by the court, is six feet wide at the bottom, eight feet wide at the top, three feet deep, and with a grade or fall of four feet to the mile. In seasons when the water has been unusually low in the dry summer months, the capacity of the canal was sufficient to take all the water of the river, but ordinarily, at the lowest stages of the stream, considerable quantities of water are discharged over the dam after the canal is filled.
The system of headworks by which the plaintiff diverts water from the river is of the ordinary type. The upper section of the canal, for a distance of about three hundred yards, is of considerably greater capacity than the canal proper, and is furnished with waste-gates and sand-gates for the discharge of silt and surplus water. At the lower end of this larger section, and at the head of the canal proper, is a gate by which the influx of the water is controlled. By means of a dam across the stream, a short distance below the head of the canal, the water is raised to the proper level to fill it. This dam, which is of stone, is about three hundred feet long on its crest. Neither the findings nor the evidence show what its height is; but, according to the only testimony on the point, it sets back the water about three-quarters of a mile—say three thousand feet, or ten times the width of the dam, and twenty times the mean width of what plaintiff calls its pond. The crest of the dam is about ten inches lower than the level at which the *45water must be held in order to turn a full supply into the head of the plaintiff’s canal, and it appears from the evidence that the dam cannot be made permanently higher without endangering the head of the canal and its banks in times of flood. Ordinarily the amount of water flowing in the stream is so large that the permanent dam holds it at a sufficient height for plaintiff’s purposes; but as the water falls with the advance of the dry season, and especially during years of extraordinary scarcity, it is necessary to add a false crest of lumber, or riprap and gunnysacks, by which the dam is raised so as to prevent any water from passing over it.
Disregarding some minor facts and some qualifications which it will be more convenient to state in connection with another branch of the case, it may be said that the foregoing statement applies to the whole period of time from the completion of the plaintiff’s dam and ditch in 1852 or 1853 down to the trial of this action. The plaintiff has at all times diverted water to the full capacity of its canal, and applied the whole of it to beneficial uses for mining and irrigation. It still requires, for irrigation and other useful purposes, all the water so diverted, and, as against a subsequent appropriator, has an undoubted right to continue such diversion unmolested and undisturbed, except in so far as a lawful appropriation and diversion of the surplus at a point above its works may involve the necessity of altering and perfecting the appliances which have thus far proved sufficient to fill its ditch.
The question is, whether it is any infringement of this right of plaintiff for the defendants, in order to appropriate the surplus and divert it to an irrigating ditch on the opposite side of the river, to tap the stream above the dam and below the head of the slack water?
There can be no question as between the parties to this action that the defendants have a perfect right to appropriate such surplus by any lawful means of diversion; and the only question is whether the plaintiff can shut them out from access to the stream at all points *46between, the upper and lower ends of what counsel call its pond.
The plaintiff’s canal is on the south side of the river. The defendants, or some of them at least, are successors in interest to the owners of a mining and irrigating ditch on the north side which was originally constructed and used as early as 1854, and was known as the Boyd’s Bar ditch. In March, 1854, the plaintiff entered into a written agreement with the proprietors of the Boyd’s Bar ditch, by which it granted to them the right to “ put in, insert, and maintain in the dam of said Hatoma Water and Mining Company” a box of sufficient size to supply their ditch, reserving the right, in case of a deficiency of water to fill its own canal, to close the gate of the Boyd’s Bar ditch, and keep it closed while such deficiency continued.
In pursuance of this agreement the predecessors of defendants put in a box two feet square on the north side of the river, and a few feet above plaintiff’s dam, through which they have ever since drawn water to supply their ditch. In 1887 the defendants posted a notice of their intention to enlarge their ditch to a capacity of two thousand inches, the diversion to be made at the Hatoma dam. In accordance with this notice they had completed the proposed enlargement up to within a short distance of the dam when this action was commenced for the purpose of enjoining them from “ completing the construction of said ditch, and tapping the said South Fork of the American river at the plaintiff’s dam, and from taking water therefrom or from any point above said dam,” etc. The enlarged ditch of defendants was of sufficient capacity to carry all the water of the South Fork at its lowest stages in a dry year, and its level being some ten inches lower opposite the dam than that of plaintiff’s canal, it would have been in the power of the defendants, upon the completion of their ditch, to drain the stream, and deprive plaintiff of all or of a great part of the water to which it is entitled.
But they have at all times disclaimed any intention *47of taking any but the surplus water over and above the quantity to which the plaintiff is entitled by its prior appropriation. In their posted notice of intention they say nothing about surplus water, but by their answer to the complaint in this action, by their testimony at the trial, and by their declarations pending, and prior to the commencement of, the action, they have uniformly insisted that they have no intention to divert any but the surplus water.
There is no finding that they have any other intention, and no evidence upon which such a finding could be sustained. The court, however, does find that “ in order to draw the surplus from plaintiff’s dam without taking the water from plaintiff’s canal, it would be necessary to raise plaintiff’s dam from twenty-two to twenty-four inches higher, and also to raise the banks of plaintiff’s canal.” This finding, and the fact that defendants, upon completion of their ditch, would have the power to drain plaintiff’s canal, are the sole grounds upon which the superior court has enjoined the defendants from completing their ditch, and it only remains to consider whether they are sufficient to uphold the decree.
It is to be observed, in the first place, that the defendants are not in any worse position than they would be if they had not succeeded to the rights of the original owners of the Boyd’s Bar ditch under the contract of 1854. Claiming, as they do, the privilege granted by that contract, they must concede, as they do concede, the prior right of the plaintiff to all the water carried by its canal at the date of the contract, but as to the surplus, they stand upon the same footing as other citizens, and may, like others, appropriate it by any lawful means. This, indeed, is not disputed, and the contention of counsel here is for the identical proposition enunciated in the findings and conclusions of the superior court; that no subsequent appropriator can tap the stream above the dam and within the slack water, because if he did it would be in his power to drain plaintiff’s *48canal, and even if lie strictly limited his diversion to the actual surplus it would compel the plaintiff to raise its dam and the banks of its canal. As to this last finding, it is not sustained by the evidence, because, although there is some slight testimony to that effect, it is contrary to reason.
The findings, no less than the evidence, show that there are times when the river carries barely enough water to fill plaintiff’s canal. At such times it is necessary to raise the dam by means of a false crest of rip-rap and gunnysacks high enough, and to make it tight enough, to prevent any water from flowing over or leaking through. The diversion of the surplus at any stage of the river would impose upon the plaintiff the necessity of doing nothing beyond what it is accustomed to do when from natural causes the surplus gradually diminishes and fails. It would simply have to raise its dam by a false crest, and make it tight enough to prevent any waste. The diversion of a part of the surplus would require a proportionate addition to the crest of the dam, and the whole effect of any diversion above the dam would be to compel the plaintiff to commence the annual operation of building a false crest a little earlier in the season than it has been accustomed to do, and to make it high enough and tight enough to prevent any waste during some years, when, without such diversion, a less efficient crest would serve to fill its canal. This is as plain and self-evident as the proposition that two and two make four, and testimony to the contrary is not worthy of consideration.
The question to be decided, therefore, narrows itself to this: Must the defendants be enjoined from tapping the stream merely because they would thereby gain the power to drain plaintiff’s canal, though they disclaim any such intention; or must they be enjoined from diverting the surplus merely because such diversion would compel the plaintiff to perform its annual task of raising its dam earlierin the season every year, and of *49making it tight and efficient oftener than they have been accustomed to do ?
To answer either of these questions in the affirmative would be equivalent to holding that there never can be a lawful appropriation of the surplus at any point above the plaintiff’s dam. For it is self-evident that a di-tch heading in the stream above the slack water with a dam sufficient to fill it would give its proprietors the same, or even more complete, power to drain plaintiff’s canal, than a ditch heading in the slack water, and it is equally evident that a diversion of the surplus, or a portion of it, at any point above the head of plaintiff’s ditch would lower the head of water behind the dam to precisely the same extent that it would be lowered by a diversion of the same quantity from the slack water. It is apparent, therefore, that there is nothing in either of the two grounds upon which the injunction was sought and granted, and upon which it is defended here, that would not equally support a similar decree, if the defendants, instead of seeking to put the head of their new ditch in plaintiff’s so-called pond, had gone a mile above the head of the slack water for that purpose. But, as above remarked, there can be no question as to the right of any lawful appropriator to divert the surplus either above or below the plaintiff.
Suppose the defendants had headed their new and enlarged ditch from a point on the stream entirely above plaintiff’s slack water, and an injunction had been sought upon either or both of the grounds I have been discussing.
As to the control they would thereby acquire over the flow of the stream, and the mere power it would give them to drain plaintiff’s canal, the obvious answer would be: The defendants have as perfect a right to appropriate the surplus as you have to the quantity first appropriated. They can take it either above you or below you, as their interest or convenience may dictate. They choose to take it above. They cannot divert the *50surplus without putting in a dam and ditch, and, therefore, the right to the surplus involves the right to the dam and ditch. It may be true that their dam and ditch will put it in their power to take all the water when the stream is low, and thereby drain your canal; but it does not follow that they will make such unlawful use of their power. They disclaim any intention of doing so. Necessarily they will be compelled to provide their ditch with a proper head-gate, and other suitable appliances for controlling the influx of water, and when the stream falls they can readily limit or shut off the flow into their ditch so as always to leave you the quantity to which you are entitled. In the mean time they cannot be enjoined from using the means essential to the exercise of their undoubted right merely because they would thereby gain the power to infringe yours. It will be time enough to enjoin them when they threaten or attempt to injure you, and the powers of a court of equity are entirely adequate to the conservation and enforcement of the rights of both parties. If the defendants fail to provide their ditch with proper head-works and you are thereby deprived, or threatened with the deprivation, of any of the water by you first appropriated, an injunction specifically framed to meet the case will compel the defendants to provide suitable works, and to exercise their rights in such manner as to leave yours unimpaired.
As to the necessary lowering of your head of water by the diversion of the surplus, that will no doubt cause you some inconvenience and trouble which you have heretofore escaped, but it is damnum absque injuria. There is but a limited supply of water in this state available for irrigation and other useful purposes, and a paramount public policy requires a careful economy of that supply. So long as there is but a single appropriator of water on a stream it matters not how imperfect or wasteful may be the means by which he diverts the quantity of water to which he is entitled. No one else is affected, and there is no ground for complaint.
*51But when subsequent appropriators divert the entire surplus at points above him he is required to use all reasonable diligence to husband what is left, and if by such diligence and the use of ordinary means of diversion he can obtain all that he is entitled to he cannot complain on account of the trouble and expense which it may involve.
In the case of Barrows v. Fox, recently decided (98 Cal. 68), we had occasion to consider this policy of the law of appropriation and to apply its principle. There a riparian owner of lands below the point at which a portion of the stream had been diverted by a prior appropriator, sought and obtained an injunction which in effect required the appropriator to substitute an iron pipe in place of his ditch and flume in order that he might receive the quantity of water he could put to a beneficial use without diverting so large a quantity from the stream. We held that the decree was in this respect erroneous, because ditches and flumes are the usual and ordinary means of diverting water in this state, and parties who have made appropriations by such means cannot be compelled to substitute iron pipes, “ though they may be compelled to keep their flumes and ditches in good repair so as to prevent any unnecessary waste.” Accordingly, we decided that the appropriator had a right to divert from the stream water enough to yield at the place of use the quantity required after the loss by absorption and evaporation, of so much thereof as is necessarily so lost in a ditch and flume well constructed and kept in good condition.
This is but the latest of a long series of decisions recognizing and enforcing the same policy; and the soundness of the doctrine upon which they rest is unquestioned.
While the right of the prior appropriator is carefully protected, he is compelled to exercise it with due regard to the rights of others and the paramount interests of the public. The quantity of his lawful appropriation cannot be diminished, but he must return the surplus *52to the stream without unnecessary waste, and he must use reasonable diligence and reasonably efficient appliances in making his diversion in order that the surplus may not be rendered unavailable to those who are entitled to it. Upon the same principle it must be held that a prior appropriator' whose means of diversion become insufficient for his purposes, by reason of their inherent defects, when the surplus is diverted above him, must take the usual and reasonable measures to perfect such means. And it is no injustice to this plaintiff to allow the diversion of the surplus waters of the South Fork by a lawful appropriator, so long as a resort to the same means it is accustomed to employ in periods of scarcity will enable it to fill its canal.
Having thus, as I think, clearly shown that the doctrine upon which the decree of the superior court is expressly based, and upon which counsel seek to uphold it, involves the absurd conclusion that the surplus waters of the South Fork cannot be diverted by a qualified appropriator at any point above the heacl of plaintiff’s canal, I will next consider some of the more technical grounds upon which counsel base their further contention.
They seem to claim that, irrespective of any question of actual injury to the plaintiff by a diversion of the surplus, and conceding that it will cause no greater or other inconvenience to take it from the dam than would be occasioned by taking it from the stream above the dam, the plaintiff has, nevertheless, such an exclusive property in the bed and banks of what they call its pond or reservoir, that to take it from the dam would be an invasion of its strict legal rights—a trespass upon its property. Indeed, the argument of counsel is that they have the same right to the pond that they have to their canal, and if the defendants can put the head of their ditch in the former, they can with equal right put it into the latter. But clearly this is not so, for in the absence of any proof of title derived from a paramount source there is an obvious and radical difference *53between the canal and the river. The plaintiff made the canal, its bed, and banks; it did not ma>ke the channel of the river. It has been permitted for its convenience to obstruct the flow of the river; to raise its level, and, necessarily, to retard its current, and to widen and deepen it above the dam, but this change in its condition leaves it still a part of the river, and it is difficult to see how those who had a right of access to it . before plaintiff’s dam was erected have lost such right merely because, by the liberality of the government, the plaintiff has been permitted to raise its level and set back its current.
There is no finding as to the ownership of the soil covered by the dam or either of the ditches. Nor is there any evidence, so far as I can discover, touching the point. In the absence of proof to the contrary, it must be assumed that these lands are public lands of the United States, as they unquestionably were at, and long after, the time when plaintiff constructed its dam and canal and made its appropriation. The rights of plaintiffs are, therefore, such as have been conferred by the grant or license of the United States. The extent of this grant or license is clearly defined by the act of Congress of July 26, 1866. It confirms such rights to the use of water as have been recognized and acknowledged by local laws and customs and the decisions of courts, and grants a right of way for ditches and canals. (14 Stats, at Large, 253.) It does not grant any land whatever, but merely the right to divert and use the water, and a right of way—an easement. There is nothing in the letter of the statute, or the terms of the grant, which authorizes the erection of a dam across a natural stream, but assuming that the grant of the water right carries with it the right to employ this reasonable and usual means of forcing the water into the canal, it cannot be held to carry anything not necessary to the enjoyment of the right granted, nor to deprive •the government of such control of the stream as is essential to the protection of other equally deserving *54objects of its bounty. To say that the first appropriator gains an exclusive right of access to the river as far above his dam as it sets the water back, is to say that he takes as an incident to what is expressly granted, something that is in no way essential to the enjoyment of his rights, but is in the highest degree prejudicial to the government by whose liberality he profits, and to all other citizens who may desire to participate in its bounty upon fair and equal terms.
Suppose that the land covered by this dam has been granted, or shall hereafter be granted, by the United States to homestead or pre-emption claimants, will anyone contend that such grantees have taken, or will take, it subject to any right of plaintiff, except the mere easement to flow it? It does not seem possible that there can be but one answer to this question. As against the United States, and those who connect themselves with the United States, the plaintiff does not own a foot of land covered by its so-called pond, or bordering upon it. If the land still belongs to the United States the defendants are granted, by the same statute under which plaintiff claims, a right of way across it to the river for the purpose of making a lawful appropriation of any water not covered by a prior right, and the plaintiff, by raising the level of the river, has not sequestered one foot of its natural channel, except so much as is covered by the material structure of its dam, or is essential to its support.
To call this inclosure formed by the dam and the sides of the cañón a reservoir is an abuse of terms. A reservoir may be formed by damming a natural watercourse where the object is the storage of a large body of water; but the object of this dam is not the storage of water, and there can be no pretense that the plaintiff has any right of property in the body of water it holds back. The whole object of this'dam is to raise the level of the stream as a means of diverting a part of it into the canal, leaving the surplus to flow over the dam and down the canon. According to the testimony the slack *55water extends more than three thousand feet above the dam, and the so-called pond or reservoir has therefore a length more than ten times its greatest width at the daili, and more than twenty times its mean width. Through it there is at all times flowing all the water of the river, out of which the plaintiff has a right to divert a limited quantity, leaving the surplus to flow on. It is, therefore, vastly more like what nature made it—• a part of the river channel—than what counsel call it—a pond.
There is no analogy between the point involved in this controversy and the point decided in Rupley v. Welch, 23 Gal. 453. There the plaintiff had constructed a reservoir for impounding the waters flowing down a ravine, which he used for irrigating a garden and orchard. The defendants were not claiming the right to take the surplus, but, as miners, claimed the right to divert “ the water,” that is, all the water from plaintiff’s reservoir to their sluices, and had accordingly done so. The report of the case is very meager, but its meaning is perfectly plain to anyone who knows how the operation of sluice-washing was conducted at that date. The defendants were digging and sluicing above the reservoir, and, of course, could not draw water for that purpose from the reservoir. What they did was to turn the water into their sluice above the reservoir and discharge it below, thereby diverting it from the reservoir. The question as to their right to tap the slack water in order to appropriate the surplus could not possibly have arisen, and clearly was not decided. The point, and the only point, contended for by the defendants was that a prior appropriation of water for irrigation was of no avail against a subsequent appropriation for mining. The court merely decided that the appropriation for irrigation was good against miners as against others, and that the defendants could not prevent the water so appropriated from flowing into the reservior prepared for impounding it. This is a doctrine which, at the present day, no one disputes, but in early mining times the para*56mount right of the miner was strenuously insisted upon by the miners, and in the mining sections often exercised with a high hand, as it was by the defendants in Hupley v. Welch, 23 Cal. 453.
To recapitulate and to conclude upon this branch of the case:
The plaintiff has shown no right to the land above its-dam, or to the bed and banks of the stream, except such as it can base upon the act of Congress of July 26,1866,. above cited. By that act it has been expressly granted a right to use the water it has appropriated and a right-of way for its ditch. It can take nothing as incidental to what has been expressly granted, except what is reasonably necessary to its enjoyment. Conceding that, this includes the site of its dam, and the right to maintain it, and to flow the lands above it, it does not include-an exclusive right to the watercourse above the dam and below the head of slack water, because such right, is not only unnecessary to the enjoyment of that which is expressly granted, but it infringes the equal rights of others. If the land above the dam is public land the same act of Congress grants to defendants a right of way over it to th'e stream, and to all parts of the stream,, for the purpose of diverting the surplus. If the land belongs" to the defendants, or if they have the grant or license of the private owner, their right of access to the-stream is equally undoubted. They are bound only in appropriating the surplus, whether within or above the slack water, to provide proper head-works for their ditch to regulate the influx of the water, so that the plaintiff may, at all times, have the quantity by it first appropriated.
These conclusions necessarily involve a reversal of the judgment, but in remanding the cause it is proper to notice other errors assigned.
The defendants, for some reason not clearly apparent, set up in their answer the contract of March, 1854, granting to the owners of the Boyd’s Bar ditch a right to put a box in plaintiff’s dam, etc. They did not allege-*57any infraction or threatened infraction of their rights under that contract, and asked for no affirmative relief. It is not easy to see what bearing the facts connected with that contract have upon the case made by the complaint or the question which it presents. But at the trial evidence was taken as to those matters, and the court made findings—not very full or explicit— upon which are based certain provisions of the decree regulating the exercise by the parties of their contract rights. The effect of the decree is to limit the defendants to a box two feet square and eight feet long, set upon a level grade with the top of the box on a level with the surface of the pond, reserving to plaintiff the right to close this box at all times when there is not a full supply of water for plaintiff’s present ditch.
Neither the findings nor the evidence support this part of the decree. It clearly appears from the evidence, and partially from the findings, that the present capacity of the ditch is materially greater than it was at the date of the contract.
It is found that the canal was enlarged and its capacity increased “inplaces” in 1862, but it is said the evidence does not enable the court to determine how much. As to the expression “in places” we know what is meant when a ditch-owner enlarges his ditch and increases its capacity in places. He does not enlarge it in the large places, but in the small places, and by so doing increases its capacity throughout. The evidence in the record shows without contradiction that plaintiff’s ditch was widened to six feet on the bottom wherever it was of less width, as it was in many places. The only conflict is as to whether it was prior to the enlargement four feet or five feet wide on the bottom. But whichever it was the enlargement was material, and a finding as to its extent was absolutely essential to a decree settling the right of the parties under the contract.
On the hypothesis most favorable to the plaintiff the capacity of its ditch prior to 1862 is indicated by a section five feet wide at bottom, seven feet wide at top, and *58three and one-half feet deep, equal to twenty-one square feet. Its present capacity is measured by a section six feet wide at bottom, eight feet wide at top, and three and one-half feet deep, equal to twenty-four and one-half feet. Its capacity in miner’s inches is not found, and the testimony does not show, with any degree of certainty, what it is; but assuming that it is two thousand four hundred and fifty inches, each square foot of the section would represent one hundred inches, and the three and one-half added in 1862 would represent three hundred and fifty inches.
The right to this quantity of water perpetually, or to a half or a quarter of it, is too important to be decreed away without a finding and without evidence to support a finding.
But the superior court seems to have thought it unnecessary to consider the evidence on this point, because in its opinion the acquiescence of the defendants and their predecessors for nearly thirty years in the enlargement of plaintiff’s ditch raised an estoppel against them.
But the defendants were not complaining of the enlargement of the canal or of its increased capacity. They never had a right, either under their contract or independent of it, to complain of such enlargement. They could only object to the closing of their ditch or the box that supplied it when there was more than sufficient water to supply the canal according to its capacity at the date of the contract, but not sufficient to supply it as enlarged. And the evidence shows that their box never was closed by plaintiff after the enlargement of its canal. Nor is it found that the plaintiff ever did any other act adverse to the rights of defendants under the contract in such manner or for such time as to gain a prescriptive right.
The decree is also unsupported by any finding as to the dimensions and setting of the box through which the defendants are entitled to draw water from the dam under the contract. The contract does not specify a' box eight feet long, or of any length, nor at what level *59it shall be set. The evidence of all the witnesses, except one who does not pretend to have measured the box actually used by defendants, or to have had any occasion to observe it with attention, is that it was only three or four feet long, and this is material; for if a box is set level, the longer it is the less water it will deliver.
It is also an objection to the decree that the level at which the box is to be set is not definitely fixed. The level of the water behind the dam is not a practicable gauge, for the evidence shows that this varies greatly according to the stage of the river. If upon a retrial of the cause the rights of the parties under the contract are again submitted for decision and regulation, the court should find the extent to which the plaintiff’s canal was enlarged in 1862, and precisely and definitely the dimensions and setting of the box which the defendants and their predecessors put in and used in pursuance of plaintiff’s grant.
The judgment and order of the superior court are reversed, and the cause remanded for a new trial.
Harrison, J., and Fitzgerald, J., concurred.