The issue that we resolve in this case arises from what respondents’ counsel characterized at oral argument as the “unfortunate” drafting of the water quality objective for bacteria in the basin plan for the Sacramento and San Joaquin River Basins (Basin Plan). In other words, the language of the Basin Plan does not read as the Regional Water Quality Control Board for the Central Valley Region (Regional Board) wishes it did and perhaps as the Regional Board intended.
It is not our role to plumb the consciousness of regulation drafters and mold the language of a regulation to comport with their undisclosed intent. As with the construction of statutes, so also in ascertaining the meaning of regulations, we divine intent from the language actually used and not the language one supposes the drafters might have used had they anticipated the legal dispute now before us. To the extent the language does not accurately reflect what the drafters had in mind and application of the language actually used could lead to an environmental catastrophe, the cries of despair should be directed to the governmental bodies empowered to alter the language. This court is not one of those bodies and should not indulge arguments that seek to amend in the guise of interpreting a regulation. Because I believe the majority opinion does that, I must respectfully dissent.
Background
The facts underlying this dispute are remarkably clear. The Regional Board adopted the Basin Plan, which sets forth the water quality objective for *1591bacteria as follows: “In ground waters used for domestic or municipal supply (MUN) the most probable number of coliform organisms over any seven-day period shall be less than 2.2/100 ml.”
In January 2004 the Regional Board adopted a revised waste discharge requirements order for the Boys Ranch wastewater treatment facility. The parties acknowledge that there are fewer than three homes within a three-mile radius of the Ranch, and there is no domestic or municipal water supply serving those homes. Therefore, the wastewater from the Boys Ranch facility is not released into groundwaters used for an existing domestic or municipal water supply. Nonetheless, the majority would approve the Regional Board’s application of the Basin Plan’s bacteria standards to wastewater discharged from the Boys Ranch treatment facility into underlying groundwaters that are not used by any existing domestic or municipal water supply.
There are good reasons for this outcome: basin plans are all about the protection of both present and future beneficial uses of water. Therefore, in establishing water quality objectives, the Regional Board must consider not only present uses but also future uses. To the extent the past offers insight into the future, past uses are also relevant. Moreover, the Regional Board offers a persuasive technical argument, that restricting water quality objectives for bacteria to current groundwater uses could allow water to become so contaminated that it could never be used for drinking water.
All this makes perfect sense. But the language of the regulation does not support these policies. Whatever our views on the wisdom of the Regional Board’s proposed order, we are not given free reign to import our notions of commonsense and good environmental policy into the language of the regulation—language that we are obliged apply by its terms. And denominating these policy notions as part of the “context” within which the language of the regulation must be construed is at best disingenuous. The interpretation of an administrative regulation is subject to the same principles as the interpretation of a statute. (Blumenfeld v. San Francisco Bay Conservation etc. Com. (1974) 43 Cal.App.3d 50, 59 [117 Cal.Rptr. 327].) We must employ the plain meaning of the regulatory text. (Environmental Charter High School v. Centinela Valley Union High School Dist. (2004) 122 Cal.App.4th 139, 148-149 [18 Cal.Rptr.3d 417] (Environmental Charter).)
There is no doubt the Regional Board could write a basin plan that would support the order it has adopted for the Boys Ranch wastewater treatment facility. However, the existing language does not.
I understand that we defer to an agency’s interpretation of a regulation involving its area of expertise. Indeed, the authorities cited by the majority *1592for this proposition also extend deference to an administrative agency’s interpretation of a statute involving its area of expertise. (Divers’ Environmental Conservation Organization v. State Water Resources Control Bd. (2006) 145 Cal.App.4th 246, 252 [51 Cal.Rptr.3d 497].) However, deference is not capitulation. The responsibility for discerning the meaning of a regulation, like that of a statute, is reposed in this court.
It is tempting to apply a more relaxed standard of review to a regulation; after all, the agency wrote it. However, like the Legislature, administrative agencies are not given unfettered authority to write whatever regulations they desire whenever they choose; procedures must be followed. Water quality control plans are in fact regulations and are neither expressly nor impliedly exempt from the provisions of the Administrative Procedure Act (APA; Gov. Code, §§ 11340 et seq., 11370 et seq.). (State Water Resources Control Bd. v. Office of Admin. Law (1993) 12 Cal.App.4th 697 [16 Cal.Rptr.2d 25].) The APA imposes substantial constraints on an agency’s rulemaking authority. (See Gov. Code, § 11340 et seq.) Hearings must be held, public comments received, and reviews conducted. We should not permit the process to be circumvented through acquiescence in the Regional Board’s interpretive powers.
While the Regional Board criticizes the County of Sacramento’s reliance on dictionary definitions in applying the language in question, we often resort to dictionaries in construing the language of statutes and regulations. Indeed, a fundamental tenet of statutory construction is that the court must first consult the words of the statute, giving them their, plain meaning. When the language at issue is clear, the courts should not indulge in construction. “A dictionary is a proper source to determine the usual and ordinary meaning of a word or phrase in a statute.” (E. W. Bliss Co. v. Superior Court (1989) 210 Cal.App.3d 1254, 1258, fn. 2 [258 Cal.Rptr. 783].)
We do not, of course, apply dictionary definitions when it is clear a different meaning was intended, as when words are used in a technical sense. However, the regional boards have proposed no good etymological reason why the nontechnical terms “[i]n ground waters used for domestic or municipal supply (MUN)” should be read as “designated for use.” The suggestion that construing the language in the present tense imports a “temporal element” is no more than skillful word play. Absent additional modifiers, it is not reasonable to suppose the Regional Board was intending to regulate the entire universe of groundwater, whether used in the past, in the present, or potentially in the future. Such a construction would, as a practical matter, render what was clearly intended to be a restrictive phrase, “used for domestic or municipal supply (MUN),” unnecessary.
*1593The majority argues: “In general parlance, the phrase [“used for’’] is broad and includes both present and future uses. For example, ‘chairs are used for sitting,’ is not limited to the chairs’ current use.” (Maj. opn., ante, at p. 1588.) The analogy illustrates the fallacy of the majority’s wordplay. The phrase “used for” only suggests present and future uses when it describes the function of an object without limitation. Thus, if the regulation simply stated “ground waters are used for domestic or municipal supply,” I would agree that groundwaters have been, can be, and will in the future be used for domestic or municipal water supply. However, the regulation does not simply describe groundwaters but places restrictions on substances discharged into groundwaters of a certain type, viz: “[i]n ground waters used for domestic or municipal supply.” To suggest that such a restriction applies to groundwaters that have in the past been used but are not currently used for domestic or municipal supply, or groundwaters that may be used for domestic or water supply at some time in this millennium or the next, makes a mockery of the language.
The majority’s interpretation defies the plain meaning rule. It is also at odds with the principle that words of a regulation must be interpreted in context, “ ‘harmonizing to the extent possible all provisions relating to the same subject matter.’ ” (Environmental Charter, supra, 122 Cal.App.4th at p. 149.) In addition to the water quality objective for coliform organisms, the same section of the Basin Plan also includes water quality objectives for chemical constituents in groundwater and for radioactivity in groundwater. However, these water quality objectives only apply to groundwaters “designated' for use as domestic or municipal supply (MUN).” The use of more restrictive language for the bacteria objective is at odds with the Regional Board’s argument that the term “used” includes waters “designated for use.” Similarly, at the same time the subject Basin Plan was adopted the Regional Board also adopted a plan for the Tulare Lake Basin that restricts the water quality objective for coliform organisms to “ground waters designated MUN.”
Perhaps this is all “unfortunate” drafting. However, the usual tools employed to discern the meaning of regulations do not permit us to modify language. Instead of seeking relief from this court, the Regional Board should pursue its administrative remedies. I also note that even in the absence of the disputed water quality objective pertaining to bacteria, the Regional Board is empowered to impose the same discharge restrictions under the authority of Water Code section 13263. This statutory procedure is more cumbersome but would address any public health concerns pending changes in the Basin Plan.
*1594To conclude, I do not agree that the language of the Basin Plan supports the trial court’s judgment. For that reason I respectfully dissent.