with whom RAPER, Justice, joins, dissenting.
I do not disagree with many of the basic legal propositions stated by the majority. I accept their interpretation of the change-of-use statute1 as one intended to restrict the extent of a water right which can be transferred to a new use to that quantity'of water which historically has been consump-tively used under the right sought to be transferred. However, I deny that the legislature may constitutionally so limit a pre-19092 right which, as I read the decision of this court in Johnston v. Little Horse Creek Irrigating Co., 13 Wyo. 208, 79 P. 22 (1904), constituted a property right to the full extent that the same had been actually and beneficially used, the only limitation upon the transfer being that it should “not injuriously affect the rights of other appropriators.” 13 Wyo. at 228, 79 P. at 24. While I would concede the right of the legislature to impose any restrictions it saw fit upon the transfer of water rights initiated after the enactment of the 1973 law and probably would agree that that restriction would be applicable to water rights which had their inception after enactment of Ch. 68, S.L. of Wyoming 1909,3 I believe that to apply the present change-of-use statute to rights which accrued before 1909, whether state or territorial, is an unwarranted and undue interference with and deprivation of property without due process of law, in violation both of the 14th Amendment to the Federal Constitution4 and § 6 of Art. I of the Wyoming Constitution.5 I would therefore hold this new restriction in change of use to be unconstitutional and void as to pre-1909 rights, which include the right here in question.
As I read Johnston — and I think consistently with the majority — the mere allowance of a water right for a designated quantity of water per second of time for a described number of acres of land did not vest the appropriator with the full and unrestricted right to take as much water from *572the stream as he saw fit within that allowance. As pointed out by the majority and as set forth in Johnston,
“As an appropriator of water obtains by his appropriation that only of which he makes a beneficial use, it necessarily follows that he cannot sell surplus water which he does not need, while retaining the original appropriation.” (Emphasis added) 13 .Wyo. at 227, 79 P. at 24.6
But within that limitation, and also as quoted by the majority,
“ * * * [t]he only limitation upon the right of sale of a water right separate from the land to which it was first applied, and to which it has become appurtenant, laid down bv any of the authorities, is that it shall not injuriously affect the rights of other appropriators. * * ” 13 Wyo. at 228, 79 P. at 24.7
To the best of my knowledge, it has been a fact of irrigation practice from its very inception that all water applied to a given tract of land for the irrigation of crops or grass thereon is not totally consumed in the process and some of that water so applied, however careful the irrigator may be, will find its way back to the stream. Under the circumstances that have usually prevailed, the first appropriator took water for irrigation, others came along and made similar appropriations, and due to the fact that none of them would require the full amount of their nominal appropriations at all times and the further fact that a certain amount of the water used by them usually returns to the stream, the total nominal appropriations from the stream can substantially exceed the amount of water that is flowing in the stream at any one time and actually available for use. The junior appropriators are said to acquire a vested right in the continuance of conditions as of the time of their appropriations.8
These vested rights of junior appropriators as recognized and declared in Johnston and other decisions9 represent a material limitation upon the property right of the *573senior appropriator. Since he cannot change or transfer his use to the injury of even a junior appropriator and since return flow is a fact of irrigation and of substantial importance to other appropriators, it follows that the senior user will usually not be allowed to transfer or change use to the extent of the water which has been actually spread upon his land, even without waste in the ordinary sense of the word, and his transfer will be reduced by some percentage because of the loss of return flow resulting from the change. As I see it, the effect of such deduction from the amount transferred is to leave the stream in the same condition that it would have been had the change not been effected; instead of receiving that quantity of water through return, a part of the original right is left in the stream to perform the same office for other appropriators as was formerly done by return flow.
Where I part company with the majority is in my disinclination to accept their equation of “beneficial use” with “consumptive use,” which permits them to classify as waste any diversion and application of water over and above the amount of water which is actually consumed in crop absorption or evaporation. I would say that applying their definition of “duty of water,” as
“ * * * that measure of water, which, by careful management and use, without wastage, is reasonably required to be applied to any given tract of land for such period of time as may be adequate to produce therefrom a maximum amount of such crops as ordinarily are grown thereon. * * * ” Farmers Highline Canal & Reservoir Co. v. City of Golden, 129 Colo. 575, 272 P.2d 629, 634, reh. den. 272 P.2d 636 (1954),
then the amount which the ordinary and careful irrigator applies to his land represents beneficial use. Neither the definition of duty of water nor of beneficial use requires that the water be applied without return flow resulting therefrom; it does not require that the irrigator shall, by exercise of consummate labor and skill and far exceeding the present standards of irrigation, apply only that amount of water which will be absorbed by whatever plant system is present upon the irrigated tract. I am neither an irrigation engineer nor experienced in irrigation practices, but as I read the cases, texts, monographs and other documents that have come to my attention,10 it is impossible under the present state of the art to effect such a precise and total use of water in irrigation as to permit us to say that beneficial use and consumptive use are the same thing. It may be true that the practice of flood irrigation is wasteful in the sense that much more water is put upon and passes over the land than can be consumed by the crops thereon, thus exposing the water to evaporation and other loss, but I know of no court or other authority which condemns as wasteful per se the use of water in flood irrigation.11
*574I therefore conclude that beneficial use and consumptive use are not the same thing, and that the average appropriator of water for irrigation purposes, limited as his legal appropriation is to the amount which he can and does beneficially use, is not guilty of waste when he applies more water to the land than can be absorbed without return flow therefrom. I then conclude that under Johnston, so long as other appropriated from the stream are not injured by the transfer, the owner of a pre-1909 water right used for irrigation may dispose of that right in any manner he sees fit, to the full extent that with careful management and use he has reasonably applied water to the land, subject only to the limitation that he cannot injure other appropriators from the stream.
In Green v. Chaffee Ditch Company, 150 Colo. 191, 371 P.2d 775 (1962), reh. den., the court was confronted with the attempted transfer of what appeared to be a grossly excessive right, that is, much more water had been granted in the decree than was necessary for the irrigation of the lands in question. The opinion sets forth the very careful findings and conclusions of the trial court: That there was substantial return of water; that the consumptive use was some 25% of the amount applied; that 90 acre feet of water were consumed by the use in the course of an irrigating season; and (this particularly interesting finding):
“ ‘ * * * That the efficiency of water on this particular land is 25%, requiring the application to this land of 360 acre feet of water during each irrigating season to produce maximum crops. That in addition to the 90 acre feet of water consumed on this land, five acre feet are lost by evaporation and seepage while the water is in transit from the headgate of the Coy Ditch to the Hoffman-Morrison farm, making a total consumptive use of 95 acre feet of water each year. * * ’ ” (Emphasis added)
The court then found that the irrigating season had been from April 15 to October 15 but also that the City of Fort Collins has an average return flow through its sewerage and other systems of 50% of the water taken in its intake pipeline. Finding that only 8 c.f.s. had been beneficially used by the sellers, and that any diversions by petitioners or others in excess of that amount “were a subterfuge and not in good faith,” the court then concluded that the city should be allowed to divert 190 acre feet at a rate of not to exceed 8 c.f.s. and only during the irrigation season from April to October.
The real pertinence of this case, to me, lies in the fact that it clearly recognized that in the exercise of good irrigation practice more water had to be taken from the stream and put on the land than could be actually consumed. The use of the term “efficiency of water” in the findings indicates that the Colorado court was convinced that there is no irrigation method that permits application to the land of exactly that quantity of water which will be absorbed by the plant life and therefore the water necessary to be applied, although not consumed, was being beneficially used. Since the water which was not consumed returned to the stream and not to a different drainage, as here, the result was the same as though beneficial and consumptive use are the same, but denial of the change on the basis of injury is a far different concept from that advanced by the majority, namely, that the difference between the water applied and the water consumed represents waste so that the appropriator has no property right therein. The Colorado court’s reference to the efficiency of water is consistent with its own definition of the duty of water, accepted by the majority, as the quantity of water which with careful management and use, without wastage, is rea*575sonably required to be applied to any given tract.
The board of control has made no determination that more water was being used for the purpose of getting water to the roots of. the plants than was necessary. Without such a finding the board’s conclusion that “the waters leaving the irrigated lands as return flow below the Topographic Divide, and entering Long Lake, are not being beneficially, consumptively used for the purposes for which the subject rights were acquired” is without factual foundation and indicates confusion on the part of the board. The question is not whether the return flow to Long Lake represents a beneficial use; the question is whether the water has been beneficially used in the irrigation of lands before commencing its flow into this lake. There is no prohibition in our law against diversion of water to another watershed, Moyer v. Preston, 6 Wyo. 308, 321, 44 P. 845, 848 (1896); Willey v. Decker, 11 Wyo. 496, 530, 73 P. 210, 220 (1903); State of Wyoming v. State of Colorado, 259 U.S. 419, 466, 42 S.Ct. 552, 66 L.Ed. 999 (1922), reh. den. 260 U.S. 1, 43 S.Ct. 2, 66 L.Ed. 1026. The use upon the lands draining into Long Lake was legal; it was beneficial. To me, there is no basis upon which the board could use the two terms in one connection.
I readily concede that in the ordinary case, where the return flow is to the same stream from which the appropriation is made, my distinction between beneficial and consumptive use would not benefit the appropriator seeking to change or transfer his right, since he must leave in the stream that amount of water which represented the return flow. But this limitation is imposed because of injury to other appropriators whose rights have vested and is an inherent limitation upon the water right vested in the senior appropriator. In the case at bar, without the presence of injury to other appropriators12 and merely by declaring the two uses to be synonymous, this court effects an arbitrary reduction of the amount of water transferred.
Engineering experts for Basin in this case tried very hard and, I think, effectively, to take into consideration all reasonable limitations upon the extent of the irrigation right. They determined that a considerable portion of the water rights sought to be transferred had not been used at all and no attempt was made to transfer that water. Intensive and less intensive uses were distinguished and a formula for determining the amount of return flow from both these uses was made. Due account was given to the irrigation season. As to those water rights used on land where the return flow was to the Laramie River, a proper deduction was made for that loss of return flow; in other words, that amount of water was left in the stream to prevent injury to other appropriations. But for many years and throughout the history of the water right the water now in dispute has been removed from the Laramie River drainage so that historically and before the rights of other appropriators had attached, all of the appropriation had been lost to the Laramie and its appropriators. Basin made no deduction for return flow as to this water because it was not necessary to prevent injury. The board’s denial of this transfer clearly gives a windfall to users on the Laramie and at the same time effects a substantial diminution of the transferrable water right. Such diminution can only operate to reduce the value of the right so that in my judgment the refusal to permit the change represents a material interference with the property right as defined in *576Johnston. This interference cannot be justified on the basis of some overriding state or public interest as original owner of the water or in the exercise of any police power, and upon the facts of this case it is improper and unjustified deprivation of interference with property which therefore is prohibited by both the federal and state constitutions.
Declarations that a statute is unconstitutional as applied to a particular situation are recognized by the jurisprudence of this state. In Addison v. Fleenor, 65 Wyo. 119, 196 P.2d 991, 993 (1948) this court held a so-called curative act constitutionally invalid in its application to one type of notice in probate matters while holding it valid as to other types of notice therein considered. It was said:
“ * * * However, a statute may be constitutional in part and unconstitutional in part. It is said in Alberts v. Town of Danforth, 281 Ill. 521,118 N.E. 33, that a law which is enacted in such general terms as to apply to all conditions of fact, both those prohibited by the constitution and those concerning which the legislature has the power to legislate, will be held valid to the extent of the legislative power. In State ex reí. v. Ross, 31 Wyo. 500, 512, 228 P. 636, 639, this court stated: “ ‘A statute clearly unconstitutional as to certain persons or things, but constitutional as to others, may be sustained as to the persons or things to which it may be applied without conflict with the Constitution, if it be believed that the Legislature would have enacted the statute with the unconstitutional parts eliminated.’ “And see the review of our cases and those of other states in the case of Har-son v. Town of Greybull [63 Wyo. 467] 183 P.2d 393. In view of the fact that the legislature of this state undertook to legislate as to all notices in probate proceedings, there is no reason to think that it would not have validated proceedings in so far as they are non-jurisdictional.”
This was in effect what the federal district court for the district of Wyoming did in Hughes v. Lincoln Land Co., 27 F.Supp. 972, 973-974 (1939). The land company had without previous authority from the board of control or otherwise commenced using water on a different section of land from that for which it had been acquired. The right had its inception prior to 1909 and in sustaining the appropriator’s right to make this change, Judge Kennedy said:
“ * * * [Considering the fact that in Johnston v. Little Horse Creek Irrigating Co., supra, it is held that the right to the use of water based upon a prior appropriation for beneficial purposes is a property right, it would seem that no statute which the State might subsequently pass could abridge that property right or reduce its value without intrenching upon the constitutional right of the owner.”
The statement of the Supreme Court of Nebraska in Enterprise Irr. Dist. v. Willis, 135 Neb. 827, 284 N.W. 326, 330 (1939) is pertinent:
“ * * * While vested water rights may be interfered with within reasonable limits under the police power of the state to secure a proper regulation and supervision of them for the public good, any interference that limits the quantity of water or changes the date of its priority to the material injury of its holder is more than regulation and supervision and extends into the field generally referred to as a deprivation of a vested right.”
I would therefore hold that the consumptive-use restriction cannot be applied to the transfer of water rights which had their inception prior to enactment of Ch. 68, S.L. of Wyoming 1909. I do this only within the narrow confines of this case and with full realization that in most instances where a change is sought, disposition of the question of injury to other appropriators will require limitation of the transfer to the amount which has been consumptively used. But in the absence of a showing of injury through deprivation of water to which junior appropriators have become entitled, I do not believe that the clause in question can properly be applied to old rights.
. Ch. 170, § 1, S.L. of Wyoming 1973, as amended by Ch. 23, § 1, S.L. of Wyoming 1974; now codified as § 41-3-104, W.S.1977.
. Following Johnston the legislature enacted Ch. 97, S.L. of Wyoming 1905, which consistent with the language in that opinion declared invalid any transfer of water rights from the lands for which acquired “which shall be injurious to any prior or subsequent appropriator.” The Johnston case came under attack from the then State Engineer as being based on an erroneous understanding of the facts and Elwood Mead, Wyoming’s first State Engineer and considered the father of the irrigation law in Wyoming, went so far as to express the wish that the legislature “will overcome the mischievous tendencies of the Supreme Court decision in Johnston v. The Little Horse Creek Ditch Company * * * (See Ninth Biennial Report of the State Engineer 1907-1908, pp. 73-74, 76). Ch. 68, § 1, S.L. of Wyoming 1909 provides in part that
“ * * * Water being always the property of the State, rights to its use shall attach to the land for irrigation, or to such other purpose or object for which acquired in accordance with the beneficial use made and for which the right receives public recognition, under the law and the administration provided thereby. Water rights cannot be detached from the lands, place or purpose for which they are acquired, without loss of priority." (Emphasis added)
The history of the Wyoming law with respect to changes of use, limitations thereon, and exceptions to the limitations is well set forth in Priority and Progress — Case Studies in the Transfer of Water Rights, by Frank J. Trelease and Dellas W. Lee in 1 Land and Water Law Review 1 (1966). The matter is further explored in a comment, Changing Manner and Place of Use of Water Rights in Wyoming, 10 Land and Water Law Review 455 (1975) by Dan B. Riggs. It is clear that the year 1909 marks an important division point in water law in this respect.
. See n.2, supra.
. “ * * * nor shall any State deprive any person of life, liberty, or property, without due process of law; * * *
. “No person shall be deprived of life, liberty or property without due process of law.”
. The concept of beneficial use has been a part of the Wyoming law from its inception. See Trelease, The Concept of Reasonable Beneficial Use in the Law of Surface Streams, 12 Wyoming Law Journal 1 (1957-58). Section 14, Ch. 55', S.L. of Wyoming 1888 directed that the priority of right to use water should be limited to “so much thereof as may be necessarily used and appropriated for irrigation or other beneficial purposes * * * It is said in Quinn v. John Whitaker Ranch Co., 54 Wyo. 367, 378, 92 P.2d 568, 571 (1939):
“The waters belong to the public or the state, and an appropriator cannot acquire a right that permits him to use more than is reasonably necessary for beneficial purposes.”
. I do not entirely understand the majority’s distinction of Johnston on the basis that it involved a change in place óf use while the case at bar is concerned with a change from agricultural to industrial use. That this court intended its ruling to be a broad one is indicated by its statement that although the water right was not to be considered a “floating right”, the opinion permits change to other land to which the right becomes appurtenant or “to other equally beneficial uses." Rejecting the argument that an irrigation right should be inseparably attached to the land for which acquired “and cannot be separated therefrom in any manner by sale, by any other equally beneficial use, or otherwise,” the court indicated that much injustice could thereby result. (All emphasis added)
. See Trelease and Lee, supra n.2, 1 Land and Water Law Review at 26. As pointed out by the authors, and notwithstanding the existence of the 1909 statute declaring inseparability, changes of use have been permitted as to pre-1909 rights and the administrative practice has been to determine the time that the appropriation has been actually and customarily used, the quantity of water that has been taken from the stream and the amount which has been returned thereto after use. Usually, the quantity so historically taken, less the amount which returns to the stream, being the consumptive use under the right, is the limit of the quantity which may be transferred, whether to a similar use in the same watershed (Pioneer Canal Co. case, 1 Land and Water Law Review at 34) or into another watershed (Wheatland Irr. Dist. case, id. at 40). The reduction in the amount of water which may be transferred eliminates any possibility of injury to junior appropriators and the rule of Johnston is applied. I note in passing that except for the clause limiting the transfer to the amount consumptively used, the 1973 statute appears merely declarative of this historical practice.
. Pertinent Colorado cases so holding are summed up in City of Westminster v. Church, 167 Colo. 1, 445 P.2d 52, 56 (1968). See also East Bench Irr. Co. v. Desert Irr. Co., 2 Utah 2d 170, 271 P.2d 449, 455 (1954).
. For example, see 2d Annual Report of the Territorial Engineer, 1889, in which there is an extensive section on the duty of water. Mr. Mead, the then territorial engineer, referred to duty of water to “mean the area of land upon which a definite volume of water will successfully produce crops.” Nowhere in this report do I find any contention that using more water than can be absorbed is a harmful practice which should be prohibited. Bulletin No. 81 of the U. S. Department of Agriculture on the Use of Water in Irrigation in Wyoming, by B. C. Buffum (1900), refers to extensive experiments in irrigation and points out the difficulties in arriving at any fixed measurement of the allowance of water that should be made to the irrigator. These reports are referred to in a comment by Alan W. Peryam, Determining Quantity in Irrigation Appropriations, 4 Land and Water Law Review 501, 508 (1969).
. While Kinney, writing in 1912, was of the opinion that irrigation practices could be vastly improved, he also considered that the “final test in all cases is whether all of the water diverted is actually applied to some useful or beneficial purpose.” 2 Kinney on Irrigation and Water Rights, 2d Ed., § 916, p. 1622. In an earlier section, 912, p. 1614, he makes this further observation:
“ * * * But, as can be readily seen, at best, as to what constitutes the actual wasting of water depends upon the facts surrounding each particular case * *
It is said in 1 Hutchins, Water Rights Laws in the Nineteen Western States 12 (1971):
*574“The strictures [against waste of water] apply essentially to unnecessary waste. — In the operation of diversion and distribution systems, it is impracticable to save every acre-foot of water. Some so-called waste is inevitable, depending quantitatively on the surrounding circumstances. Because of practical considerations, therefore, the inhibition against waste of water means unnecessary waste, which is not tolerated in the State policies relating to beneficial use of water.”
. With reference to this particular use, the board found that
“ * * * return flow from said lands entered Long Lake which constitutes a closed basin, and none of the flows return to the Laramie River.”
Notwithstanding this finding, the board made the further finding (I would call it a conclusion) that
“ * * * return flows are not consumptively used below the divide and that such return flows are credited to the Laramie River system as hereinafter set forth in the Order.”
The plain effect of this is that junior appropriators on the Laramie have available to them a certain quantity of water that was never available before.