concurring in part and dissenting in part.
¶ 55 The essence of this dispute is Arizona Water’s position that the Groundwater Code’s conservation measures do not require it to change its operations in any significant way. Its position is that the Department can impose limits on the per capita water use of its customers, but that a private water company only has a limited role in implementing those limits.
¶56 I believe the Department properly implemented the Act by making providers the primary focus of the per capita water conservation measures. This recognizes that providers differ significantly in their sources and uses of water while allowing providers considerable latitude in developing conservation plans and programs suitable for their own customers and geographic areas. It also recognizes that providers ultimately control whether customers receive groundwater or water from other sources. Because the trial court never squarely addressed the essential issues of this ease, and because I disagree with its finding that the Second Management Plan (“SMP”) cannot be enforced against Arizona Water because the municipal conservation program fails to address water utilization by end users, I respectfully dissent.
¶ 57 After exhausting administrative remedies, Arizona Water challenged the applicability of the Department’s SMP to its Apache Junction water system in superior court. It argued the SMP improperly (1) regulated municipal providers under the provision of the Groundwater Code that applies solely to water users, (2) included Central Arizona Project (“CAP”) water in the calculation of its conservation requirements, (3) failed to regulate individual users, and (4) conflicted with the Arizona Corporation Commission’s jurisdiction to regulate private water companies.5 The trial court determined that the SMP must regulate end users and never squarely addressed the remaining issues.
¶ 58 The majority affirms the trial court on the end user issue, but goes on, correctly I believe, to decide the CAP issue. I concur in the portion of the opinion addressing the inclusion of CAP water in the GPCD calculation.
*544¶ 59 The majority also correctly resolves the issue of conflicting jurisdiction between the Department and the Corporation Commission by noting that the Commission does not see an irreconcilable conflict. The Department and the Commission regulate Arizona Water in different ways, with the Department’s focus being on the source and quantity of water' available. The Commission regulates a private water company’s relationship with its .customers. If sufficient water is not available to serve them all, the Commission will have to approve any curtailment plans. There is no inevitable conflict between the jurisdictions of the Department and the Commission, and we should not address a speculative conflict.
¶ 60 Although the majority agrees that the per capita water conservation provisions of the SMP apply to a municipal provider, see ¶ 27, it chooses not to fully address the issue because it thinks the issue was not raised in Arizona Water’s response or that the facts surrounding the GPCD limit may change upon remand. I believe the issue was squarely raised by Arizona Water, both in the trial court and here, and that the issue cannot be separated from the end user issue. Moreover, Arizona Water’s witness at the administrative hearing testified that the “crux-of the problem” of compliance with the GPCD requirement was the inclusion of CAP water in the calculation. Waiting for the numbers to be reworked upon remand will not change this, particularly in light of Arizona Water’s repeated statements that there is little potential for conservation by end users in its service area. Failure to definitively resolve this issue will needlessly prolong this litigation. Therefore, I address it in more detail.
¶ 61 Arizona Water argues in its answering brief that “A.R.S. § 45-565(A)(2) does not permit the Department to impose a GPCD requirement on providers who unthdraw and distribute groundwater. Rather, the statute mandates that conservation requirements shall be placed on those ‘individual users’ who use groundwater (i.e., end users or customers).” The trial court accepted the argument that the SMP must address end users, but never answered the more basic question whether the GPCD requirement may be imposed on Arizona Water.
¶ 62 Both this Court’s holding in Water Users and the majority’s holding regarding CAP water implicitly accept the fact that the per capita water conservation provisions of A.R.S. § 45-565(A)(2) apply to providers. The legislature’s intent to impose the obligation is further shown by the language of A.R.S. § 45-565.01, which allows a provider to comply with a non-per capita conservation program.6 Whether the SMP must directly regulate end users or not, Arizona Water must comply with the GPCD requirements of the SMP.
¶ 63 Arizona Water argues this is unfair because Apache Junction has experienced significant increases in demand by non-residential water users. The increase in nonresidential use increases actual demand without increasing the population factor used to compute compliance with the GPCD program. I believe the statutory requirement that the SMP include reductions in per capita water usage mandates a conservation plan based on population, not non-residential use, so the SMP is valid.
¶ 64 In the First Management Plan, the Apache Junction system was assigned a total GPCD requirement of 144 (gallons per capita per day). At that time groundwater was the system’s only source of water. In preparing the SMP the Department determined that the actual GPCD for 1984, 1985 and 1986 were 172, 141 and 171, respectively.7
¶ 65 The SMP’s target rate for Arizona Water’s Apache Junction system was also 144 GPCD, dropping to 141 GPCD in 1995 (141 GPCD was the minimum for any water system). The reduction from 144 to 141 was based on the Department’s determination *545that there was some conservation potential in interior water use by existing customers and in water use by new customers. When the SMP was promulgated in 1989 the Apache Junction service area’s population was estimated to be 20,557, and it pumped and used approximately 2,400 acre feet of groundwater. In 1988, Arizona Water also began to use its allocation of 6,000 acre feet of CAP water, using 1,466 acre feet in 1989. The Department determined that Arizona Water’s actual GPCD for 1989 was 167.
¶ 66 By 1997, the population of the system increased by approximately 50 percent, and the use of groundwater had increased to 3,920 acre feet. CAP deliveries were 4,496 acre feet. The Department calculated the actual GPCD as 271. At the 1998 administrative hearing Arizona Water’s witness testified that a GPCD of 290 would allow it to serve its existing customers, but that future growth could lead it to ask for additional increases.
¶ 67 There is no dispute that the increase in GPCD resulted mainly from increases in non-residential uses. Arizona Water describes the change as follows:
Perhaps most critically, the water use characteristics of AWC’s customers in its AJ System have changed dramatically since the enactment of the Groundwater Code. In the early 1980s, Apache Junction was a rural residential area. It has since experienced a dramatic increase in nonresidential uses. As a result, according to the Department, the water usage rate by utility customers served by the AJ System has increased from 141 gallons per capita per day (“GPCD”) in 1984 to 281 GPCD in 1997. AWC’s customers’ increasing demand for water for non-residential uses is the result of industrial facilities and golf courses being developed in AWC’s service area. For example, six full-size golf courses and one executive (9-hole) course • have opened in Apache Junction since the First Management Plan was adopted.
Five of these courses have been built since 1994. Notably, AWC supplies all of the full-size golf courses exclusively with a combination of imported Central Arizona Project (“CAP”) water and effluent, and the nine-hole executive golf course receives only a small portion of groundwater. (Citations omitted.)
Significantly, the use of CAP water by Arizona Water and its customers is not regulated by the Groundwater Code. In effect, Arizona Water has chosen to serve new nonresidential customers, such as golf courses, by delivering unregulated CAP water, while new residential customers are served by pumping more groundwater.8
¶ 68 Arizona Water argues that the Department must increase its GPCD to reflect this choice. The Department points out that the Groundwater Code requires “reasonable reductions in per capita use,” AR.S. § 45-565(A)(2), and management plans are directed to include a continuing mandatory conservation program “designed to achieve reductions in withdrawals of groundwater.” A.R.S. § 45-563(A)(emphasis added). As this Court recognized in Wafer Users, and the majority recognizes in its discussion of CAP water, reductions in groundwater use will not occur if non-groundwater sources of water are left out of the equation. See Water Users, 181 Ariz. at 143, 888 P.2d at 1330.
¶ 69 The requirement to achieve reductions in per capita use allows a provider to increase its water use as its population increases. Nevertheless, the provider is generally prevented from serving new large non-residential uses without a proportionate increase in population. Although this may prevent a provider from serving all the new non-residential uses it would like to serve, this does not result from any arbitrary decision by the Department, but from the legislature’s mandate that per capita water use should be reduced.
¶70 Imposing the GPCD requirement on providers, and including CAP water in the *546calculation, leads to reductions in groundwater use by requiring municipal providers with new non-groundwater sources, such as CAP water, to replace existing groundwater uses with non-groundwater instead of using the new water to serve large new non-residential uses such as golf courses. Arizona Water complains that this penalizes its service area for being undeveloped prior to the enactment of the Groundwater Code because non-residential water usage in areas previously developed would be built into those areas’ GPCD. For example, groundwater used to water a golf course built in 1979 will be included in the calculation of the GPCD limit but water used to serve golf courses built in the 1990s must fit within the previously determined limit. Arizona Water may have a valid complaint, but its conclusion that water usage limits cannot legally be imposed if they limit non-residential growth is erroneous. The concept of priority of earlier users is embodied in Arizona water law. See Arizona Copper Co. v. Gillespie, 12 Ariz. 190, 100 P. 465 (1909). The Groundwater Code follows this concept by allowing existing users to continue at the same level subject to the conservation programs established in the management plans. New uses, however, are limited. A.R.S. §§ 45-464 (limiting increases in non-irrigation uses of groundwater); 45-465 (limiting irrigation uses of groundwater).
¶ 71 The legislature has plainly enacted a policy of limiting groundwater use, and reducing per capita water usage as a means of meeting such limits. The Department’s policy of giving municipal providers a target GPCD that includes water from most sources is a rational way of implementing that policy. Arizona Water’s claim that the per capita limits do not apply to it, or should be increased, should be rejected.
¶ 72 Both parties extensively discuss the alternatives to the total GPCD program that are available to water providers. Each alternative allows providers with access to non-groundwater supplies to expand non-residential service in a manner that would not be allowed under the total GPCD program, but imposes other limits on the use of groundwater. Arizona Water argues these plans are not suitable for it. The Department disagrees. In either case, the significant points are that the GPCD applies to Arizona Water and CAP water is included in the calculation. The availability of alternatives to the GPCD limits does not change this. The alternatives do, however, show that the legislature and the Department have not taken a one-size-fits-all approach to water conservation. If Arizona Water does not find the alternatives to its liking it should not look to the courts to set aside the GPCD program, but to the legislature to change the statutes. We should not set aside the management plan merely because Arizona Water has difficulty complying with its terms. See Hunt v. Norton, 68 Ariz. 1, 11, 198 P.2d 124, 130 (1948) (if a statute is oppressive or unworkable, relief lies with the legislature).
¶ 73 Furthermore, Arizona Water’s arguments that the alternative programs do not work for it are based on circumstances existing in 1998, after it had committed its CAP water to newly built golf courses. They do not address whether Arizona Water could have benefitted from the Alternative Conservation Program in 1989 when the SMP was issued, or the Non-Per Capita Conservation Program in 1992 when it was enacted by the legislature. We will never know what would have happened if Arizona Water had attempted to comply with the SMP by using its CAP allocation to substitute for increased groundwater pumping. This may have required asking the Arizona Corporation Commission to approve a curtailment plan allowing Arizona Water to limit service to new large non-residential users such as golf courses, but doing so would be fully consistent with the policy of the Groundwater Code to “conserve, protect and allocate the use of groundwater resources of the state.” A.R.S. § 45-401(B). As the facts currently exist, Arizona Water may find it very difficult to comply with the GPCD limits, but this difficulty largely results from its own choices, not from any arbitrary and capricious portion of the SMP.
¶ 74 Without addressing the GPCD or CAP issues the trial court set aside the SMP because it found that it failed to regulate all end users.9 The majority accepts this. I do *547not. As explained below, I do not believe the statutes support the trial court’s ruling. Even if they did I do not believe Arizona Water is entitled to have the plan set aside merely because it does not address end users. Arizona Water repeatedly states that its inability to comply with the GPCD requirement is mainly due to the inclusion of CAP water in the calculation and its delivery of CAP water to new golf courses. It also repeatedly points out that the Department cannot regulate the use of CAP water by those golf courses. Because CAP water is properly included in the calculation, amending the plan to regulate end users will not significantly affect Arizona Water’s lack of compliance with the GPCD requirement.
¶ 75 The majority acknowledges that “there is no specific statutory provision by which the legislature definitively ordered the Department to create and impose conservation measures for end users,” but believes a requirement that a plan must include such regulation is the most reasonable and sensible interpretation. I disagree for several reasons.
¶76 First, the legislature has given the Department the authority to develop management plans and conservation requirements. “[Tjhis court gives great weight to an agency’s interpretation of statutes and its own regulations.” Water Users, 181 Ariz. at 142, 888 P.2d at 1329. We properly gave great weight to the Department’s interpretation of the Groundwater Code in Water Users, and the majority does so again in this case by including CAP water in the GPCD calculation. We should do the same in interpreting the end user requirements. The Department has interpreted the statutes as giving it the authority to regulate end users, but not mandating such regulation. Given the lack of specific statutory language to the contrary, its interpretation is reasonable.
¶ 77 Moreover, whether it is sensible to regulate end users is simply not addressed by the record before us and is completely beyond our expertise. The Department is required by statute to develop management plans after publicly presenting data in support of the plan. See A.R.S. § 45-570 (2003). After a public hearing at which any person may submit evidence for or against the adoption of the plan the Department must make and file a written summary and findings with respect to matters considered during the hearing. Id.; A.R.S. § 45-571 (2003). After completing this process for the SMP the Department concluded that direct regulation of most end users was not appropriate. The legislature delegated such choices to the Department, not to us, so we should leave its choices in place.
¶ 78 Next, the key language of the Groundwater Code states that the SMP must “require additional reasonable reductions in per capita use to those required in the first management period and use of such other conservation measures as may be appropriate for individual users.” A.R.S. § 45-565(A)(2). The language “as may be appropriate for individual users” is the only statutory language to specifically address conservation requirements for end users. It plainly does not require restrictions on all end users, but only as the Department determines “may be appropriate.” The words “as may be appropriate” are permissive rather than mandatory, and give the Department discretion to determine which, if any, individual users should be regulated directly through conservation requirements. The trial court effectively read the phrase “as may be appropriate” out of the statute. As the most specific reference to conservation requirements for end users, I find it controlling.
¶ 79 The statutory language that the management plans include “reductions in per capita use” also leads me to believe that the legislature did not mean to require that all end users be directly regulated by the Department. The phrase refers to reductions in the average use per person and does not require reductions by any particular user. While the Department does have the authority to directly regulate individual users of groundwater, as it considers appropriate, the legislature generally allows each provider the flexibility to develop conservation plans that will be appropriate for its own environment.
*548¶80 The majority relies on general language in several other provisions of the Groundwater Code instead of the specific language of A.R.S. § 45-565(A)(2).10 None of these provisions is as specific as the “as may be appropriate” language of A.R.S. § 45-565(A)(2), so the discretion given the Department by that section should be recognized. Section 45-463, A.R.S., does refer to persons “receiving” groundwater, but the general nature of the provision is not sufficient to overcome the specific language of section 45-565(A)(2). Moreover, the Department believes that it has developed a conservation program for all persons in the SMP by imposing conservation requirements on providers, as well as by considering end user restrictions for a wide variety of end users in its development of the SMP. Given the lack of specific language requiring regulation of end users, I cannot conclude that the legislature intended the management plans to be invalid in the absence of such regulation.
¶ 81 Citing “common sense,” the majority states that “if the manager is to obtain the desired conservation result, all those participating in the cycle must be managed directly in regal’d to their conservation responsibility, including the customer who uses the groundwater and not just the provider who extracts, transports, and delivers it to him.” The legislature has recognized, however, that regulating water use in this state is an incredibly complicated task, and has created the Department to carry it out. A.R.S. § 45-103(2003). After public hearings and due consideration the Department concluded that it was appropriate to directly regulate only certain individual users. We should defer to that conclusion.
¶ 82 Moreover, it is not clear to me that direct regulation of all end users is sensible water policy. The Groundwater Code recognizes that water providers are not in identical situations. Some have extensive surface water rights, while others rely exclusively on groundwater. Some have CAP allocations or the ability to acquire additional water rights. Local water providers have the best understanding of their own situations and may reasonably choose different methods to achieve their conservation targets. Uniform end user restrictions throughout an active management area, or even a local service area, may not be the most effective conservation method. Indeed, imposing conservation requirements on all end users who receive groundwater may do little to reduce total groundwater use if the provider can exempt select customers from the requirements by serving them with non-groundwater.11 The resources devoted to creating and enforcing individual conservation requirements may be more effectively utilized in other ways. Again, this is the type of decision the legislature has left to the Department, not to us.
¶ 83 Arizona Water complains that a private company has no authority to force conservation measures on individual users, so such actions must be taken by the Department. Once again, the statute requires limits on individual users only as the Department finds they “may be appropriate.” Moreover, private water companies do have the ability to influence water usage by them customers. As the Corporation Commission *549states in its brief, “there is nothing to prevent Arizona Water from asking the Commission to allow it to curtail service in appropriate circumstances.” The record also shows that Arizona Water’s customers are already very efficient in them use of water compared to other areas of the active management area. This efficiency was achieved without Arizona Water having the power to mandate conservation requirements, so it appears that there are measures that a private water company can take to encourage efficiency.
¶ 84 The tidal court’s ruling regarding end users does little to resolve this dispute. Because the statute itself does not specify how or which individual users are to be regulated, the trial court was unable to articulate how the Department could correct the management plan. In a conference with the parties the trial court tried to explain its ruling:
That may sound more significant than it is, however, I did not [conclude] that the Department needs to address user by user, the allocation of water to every potential user and actual user. I do not think that is the law, and I don’t think that is what the Department needs to do.
And I hesitate to keep repeating. I don’t think that means an allocation for each user or necessarily even for each category of user, but in some way we have to meet the statutoiy mandate of having something in a plan that addresses the problem with an end user rather than putting the intermediary in this case, Arizona Water Company, in a position of deciding who to serve and how to serve them.
The trial court’s final order simply concluded that “[t]he SMP cannot be enforced as written because the municipal conservation program fails to address water utilization by end users.”
¶ 85 As noted above, the Department believes it complied with the statutes by considering conservation measures for individual users and including the three it found appropriate, as well as by indirect regulation through providers. At oral argument before us, Arizona Water articulated a position that all users must be addressed, but that it could be done by classes. The trial court’s statements disagree with both these positions, but fail to explain what it would regard as passing legal muster. The conclusion I draw is that no matter what the Department does Arizona Water is likely to disagree because it is impossible for the Department to tie its actions to any specific statutoiy language. More years of litigation will follow.
¶86 The reason the trial court had so much trouble articulating a standard against which the SMP should be judged is that the legislature did not provide such a standard. The legislature gave the Department the authority to develop the plan, and the plan could include conservation measures “as may be appropriate” for individual users. The legislature set out a detailed and public procedure the Department must follow in developing the plan, but beyond that the details were left to the sound and educated discretion of the Department. Arizona Water does not argue that the specific end user measures adopted by the Department are not “appropriate.” If it made such an argument courts would have a statutoiy basis upon which to review the actions of the Department. The trial court’s order here, however, merely tells the Department to again exercise its discretion to develop a management plan, but to do it better. Its inability to be more specific is strong evidence that the language of the statute simply does not support its ruling.
¶87 “Neither this court nor the superior court may substitute its judgment for that of the agency on factual questions or matters of agency expertise,” but “[w]e apply our independent judgment ... to questions of law, including questions of statutoiy interpretation and constitutional claims.” Webb v. State ex rel. Ariz. Bd. of Med. Exam’rs, 202 Ariz. 555, 557, ¶ 7, 48 P.3d 505, 507 (App.2002). Whether the SMP must directly impose conservation requirements on end users, and to what extent, is simply not a question of statutoiy interpretation that we may independently decide. The statute unambiguously provides that the conservation program will include “such other conservation measures as may be appropriate for individual users.” A.R.S. § 45-565(A)(2). Determining what is “appropriate” falls within the Department’s mandate and expertise *550and requires extensive knowledge of water law, science, practice and policy. Because the statute does not contain a specific mandate that the SMP must directly regulate end users, neither this Court nor the superi- or court should substitute its own judgment as to what constitutes sound water policy for this state.
¶ 88 For these reasons I respectfully dissent from the majority’s affirming the trial court’s order setting aside the SMP. I would reverse the trial court on that issue and remand for further proceedings. I concur in the majority’s analysis of the CAP water. Under my analysis, Arizona Water would not be the prevailing party, but in light of the majority’s ruling I agree that Arizona Water was the prevailing party in the trial court and concur in the majority’s analysis of the attorneys’ fees issue.
. Although not relevant to this appeal, Arizona Water also argued that the Department improperly calculated its GPCD requirements in several ways, enforcement of the SMP and GPCD requirements resulted in an impermissible taking in violation of the United States and Arizona, constitutions, and the SMP and GPCD unfairly discriminate against Arizona Water in violation of the equal protection clause.
. The majority finds A.R.S. § 45-565.01 irrelevant to the issue of whether the statute requires that conservation measures be imposed on end users. As I read the argument, the Department primarily cites the statute to counter Arizona Water’s argument that the GPCD requirement applies only to end users.
. Arizona Water successfully argued in the administrative process that the Department under-counted the population of its Apache Junction service area in calculating GPCD. In general, if a higher population number is used in the calculation, the GPCD number is lower.
. The record does not fully explain the rationale for this choice, but it may be related to the fact that CAP water costs more than groundwater. If Arizona Water served existing customers with CAP water instead of groundwater it would be adding additional costs that would have to be passed on to those customers. By serving new customers with CAP water the added costs are covered by new revenue sources. The record shows that Arizona Water has agreements with the golf course owners regarding their receipt of the CAP water, but the agreements themselves are not in the record.
. The SMP does contain conservation requirements for three types of individual users: turf-related facilities (schools, parks, cemeteries, golf *547courses and common areas of housing developments that apply water to a water-intensive landscaped area of ten or more acres), publicly owned rights-of-way, and new large cooling users.
. See ¶¶ 15-17, citing A.R.S. §§ 45-401(B) (general policy that the Code was designed to create a framework for the "comprehensive management and regulation of the withdrawal, transportation, use, conservation and conveyance of rights to use groundwater in this state”); 45-492(A) (granting municipal providers in an active management area "the right to withdraw and transport groundwater within its service area for the benefit of landowners and residents within its service area, and the landowners and residents are entitled to use the groundwater delivered," each "subject to ... [cjonservation requirements developed by the director pursuant to article 9 [management plans] of this chapter.”); 450563(A) (requiring "a continuing mandatory conservation program for all persons withdrawing, distributing or receiving groundwater”).
. For example, the SMP’s restrictions on turf facilities such as golf courses do not apply to the large golf courses served by Arizona Water because it has chosen to serve them only with CAP water. Arizona Water’s witness at the administrative hearing testified that the original Gold Canyon golf course was constructed in the early 1980s and was first served by groundwater, but later switched to CAP water. The ability of a water provider to switch a customer from a regulated source of water to an unregulated source highlights the need to include CAP water in the GPCD calculation and the difficulty of achieving per capita reductions in water usage if only end users of groundwater are regulated.