Filed 6/16/14
                      CERTIFIED FOR PARTIAL PUBLICATION*

                IN THE COURT OF APPEAL OF THE STATE OF CALIFORNIA

                             FIRST APPELLATE DISTRICT

                                      DIVISION ONE


RUDOLPH H. LIGHT et al.,
        Plaintiffs and Respondents,
                                                  A138440
v.
STATE WATER RESOURCES                             (Mendocino County
CONTROL BOARD,                                    Super. Ct. No. SC UK CVG 1159127)
        Defendant and Appellant.

RUSSIAN RIVER WATER USERS FOR
THE ENVIRONMENT et al.,
        Plaintiffs and Respondents,
v.
STATE WATER RESOURCES
CONTROL BOARD,
        Defendant and Appellant.


        In April 2008, a particularly cold month in a dry year, young salmon were found
to have been fatally stranded along banks of the Russian River stream system, which
drains Sonoma and Mendocino Counties. Federal scientists concluded the deaths were
caused by abrupt declines in water level that occurred when water was drained from the
streams and sprayed on vineyards and orchards to prevent frost damage. Following a
series of hearings and the preparation of an environmental impact report, the State Water
Resources Control Board (Board) adopted a regulation that is likely to require a reduction


        *
         Pursuant to California Rules of Court, rules 8.1105(b) and 8.1110, this opinion is
certified for publication with the exception of part II.E.
in diversion of water from the stream system for frost protection, at least under certain
circumstances. The regulation itself contains no substantive regulation of water use,
instead delegating the task of formulating regulatory programs to local governing bodies
composed of the diverting growers themselves. The regulation declares that any water
use inconsistent with the programs, once they have been formulated and approved by the
Board, is unreasonable and therefore prohibited. The trial court granted a writ of
mandate invalidating the regulation on several grounds. We reverse.
       Foremost among plaintiffs’ grounds for challenging the regulation is their
contention the Board lacks the regulatory authority to limit water use by riparian users
and early appropriators, whose diversion is beyond the permitting authority of the Board.
Although the Board has no authority to require such users to obtain a permit to divert,
there is no question it has the power to prevent riparian users and early appropriators
from using water in an unreasonable manner. We conclude that, in regulating the
unreasonable use of water, the Board can weigh the use of water for certain public
purposes, notably the protection of wildlife habitat, against the commercial use of water
by riparian users and early appropriators. Further, the Board may exercise its regulatory
powers through the enactment of regulations, as well as through the pursuit of judicial
and quasi-judicial proceedings. Because this is a facial challenge, our ruling is a narrow
one, grounded in the general authority of the Board; we have no occasion to rule on the
validity of any particular substantive regulation that might be approved by the Board in
the process of implementation.
       We also conclude the Board properly found the regulation to be necessary to
enforce water use statutes and did not unlawfully delegate its authority by requiring local
governing bodies to formulate the substantive regulations. Finally, we find no error in
the Board’s certification of the environmental impact report.
                                   I. BACKGROUND
       The stream system of the Russian River is home to three species of salmon
classified as either threatened or endangered under the federal Endangered Species Act of
1973 (16 U.S.C. § 1531 et seq.). The river and its tributaries, which flow to the sea


                                             2
through Mendocino and Sonoma Counties, contain over 1,700 miles of potential salmon
habitat. In late fall and winter, adult salmon enter the river from the ocean, swim
upstream, and lay eggs in gravel on the streambed. The eggs typically hatch in late
winter, and the fry emerge from the gravel after four to eight weeks and move to shallow
water, typically near the margins of the stream. Here the young salmon, known as
salmonids, spend several months, moving into deeper water as they mature.1
       In April 2008, when unseasonably cold weather followed an exceptionally dry
winter, the National Marine Fisheries Service (Fisheries Service) discovered two
episodes of fatal strandings of salmonids in the mainstem Russian River and a tributary
stream. “Strandings” occur when salmonids in shallow areas of the watercourse are left
without water or are trapped in isolated pools. There is evidence suggesting the problem
is not necessarily one of low water levels per se, but of sudden decreases in water level,
which allow the salmonids insufficient time or opportunity to seek the protection of
deeper water. Because the salmonids spend their time in shallower water near the stream
banks, they may be particularly susceptible to such sudden decreases. Extrapolating from
the available limited data, the Fisheries Service reached a “coarse but conservative”
estimate that some 25,000 salmonids had been killed throughout the stream system in the
April 2008 events.
       The Fisheries Service blamed the strandings, in large part, on agriculturalists,
especially grape growers, located along the system. The watershed of the Russian River
is home to over 60,000 acres of vineyards, of which 70 percent are within 300 feet of
salmonid habitat. Grape plants are particularly susceptible to frost damage when new
growth appears in the spring. The newly emerged vegetation is delicate, and a tissue-
killing freeze can result in substantial crop loss. A time-tested method of preventing frost
damage is to spray the new growth with water, which by freezing on the plants insulates
them against the colder air. If a number of growers anticipating a frost all draw their


       1
      The life cycles of the three species of salmon differ somewhat, but this general
summary is characteristic of all three.


                                             3
water directly from a stream at the same time, the net effect can be a sudden decrease in
the volume of flowing water. The problem occurs both because the growers’ diversion of
water is effectively synchronized—all growers in a threatened area must frost-protect at
the same time—and because the overhead sprayers necessary for frost protection
consume relatively large quantities of water. Examining data for March through
May 2008, the Fisheries Service found an association between near-freezing air
temperatures and sudden and substantial drops in the flow of a stream in the system.2
       In a letter, the Fisheries Service urged the Board to undertake regulatory activity to
reduce the risk of frost protection-related salmonid deaths. Although the Fisheries
Service pointed the finger at growers, other factors were potentially involved. Most
obviously, the affected area of the stream system is downriver of two large reservoir
lakes created by the Coyote and Warm Springs Dams. The pace of water release from
these dams directly affects the level of water in the system. Following the discovery of
the stranding deaths, the agency responsible for controlling the release of water from the
dams, the Sonoma County Water Agency (SCWA), experimented with anticipatory
releases of water to counteract the effects of frost protection diversion. The SCWA
concluded such releases were impractical, given the long time, up to 14 hours, necessary
for the released water to reach the more distant portions of the stream system and the
difficulty in predicting frost events, which gave rise at times to wasteful “false alarm”
releases. In addition, the coordinated nature of the frost protection diversions made it
difficult to counteract their impact. The SCWA told the Board additional anticipatory
releases would be ineffective in preventing the sudden drawdowns.
       On the other hand, while protecting sensitive crops from frost is of critical
commercial importance, the practice can be managed to reduce the immediate demand on

       2
         Of the total of 1,778 water rights claims in the Russian River watershed, 533
provide for the diversion of water for frost protection. A witness before the Board
compared air temperature and water flow at a gauge in the Russian River over the 17
years prior to 2009 and found a correlation between the occurrence of low air
temperatures and rapid drawdown. The intensity of the drawdowns had increased
significantly in recent years. Such drawdowns did not occur in areas without vineyards.


                                              4
stream flows. Growers can minimize their use of sprayed water by precisely targeting
truly threatened acreage, and better frost forecasting and temperature monitoring can
avoid unnecessary sprayings. Many growers have constructed basins to collect water at
times of high stream flow. Drawing water from such basins or from wells, rather than
directly from the stream system, serves the same frost protection purpose without an
immediate impact on stream flow. In addition, there are alternative methods, such as
wind machines, heaters, and cold air drains, that will work under certain circumstances to
protect against frost damage.
       Following the 2008 discovery of salmonid deaths, the Fisheries Service formed a
task force and attempted to organize voluntary efforts to reduce the impact of frost
protection on the stream system. While it praised the efforts of participating growers, the
Fisheries Service eventually concluded the problem could not be managed through
voluntary efforts. The submitted proposals for voluntary action generally did not address
diversion in the tributary streams of the river, where the problem was most acute, and the
inability to compel the compliance of all growers with a voluntary plan made success
unlikely. Based on the Fisheries Service’s experience, the Board concluded voluntary
efforts would not solve the problem.
       Following a series of public hearings and the preparation of an environmental
impact report, in September 2011 the Board adopted a regulation addressing diversion for
frost protection, codified as California Code of Regulations, title 23, section 862
(hereafter Regulation 862). Regulation 862 applies to “any diversion of water from the
Russian River stream system . . . for purposes of frost protection from March 15 through
May 15.”3 (Regulation 862, subd. (a).) The section contains no substantive regulation of
water diversion for the purpose of frost protection, instead delegating the development of


       3
        The regulation actually applies only to that portion of the Russian River stream
system located downstream of the two major dams. (Regulation 862, subd. (a).) Because
salmon cannot migrate past the dams, there is no risk to their safety from water diversion
above the dams. The dates were apparently selected because they represent the time
during which new plant growth typically coincides with the risk of freezing temperatures.


                                             5
such regulation to “water demand management program[s]” (WDMP’s). Regulation 862
is silent as to how and by whom the WDMP’s are to be developed, but they must be
administered by “an individual or governing body . . . capable of ensuring that the
requirements of the program are met.” (Id., subd. (b).) The parties reasonably assume
the WDMP’s will be created by self-organized groups of agricultural diverters, who will
act as the “governing bodies.” Each WDMP must be submitted annually to the Board for
approval. (Ibid.)
        As described in Regulation 862, the fundamental functions of the WDMP’s are to
develop and implement methods for monitoring the “stage,” or height, of the affected
watercourses, determining when that stage poses a threat to young salmon, and
responding with “corrective actions” to reduce a threat once detected. (Id., subds. (b),
(c)(2)–(4).) Among other requirements, the WDMP must contain an inventory of
potential diverters “within the area subject to the WDMP,” including diverters who
“declined to participate,” a stream stage monitoring program, and a plan for managing
frost protection diversion to prevent strandings. (Id., subds. (c)(1)–(5).)
        Regarding potential “corrective actions,” Regulation 862, subdivision (c)(4) states:
“If the governing body determines that diversions for purposes of frost protection have
the potential to cause stranding mortality, the governing body shall notify the diverter(s)
of the potential risk. The governing body, in consultation with the diverters, shall
develop a corrective action plan that will prevent stranding mortality. Corrective actions
may include alternative methods for frost protection, best management practices, better
coordination of diversions, construction of offstream storage facilities, real-time stream
gage and diversion monitoring, or other alternative methods of diversion. . . . In
developing the corrective action plan the governing body shall consider the relative water
right priorities of the diverters . . . .”
        Once a program has been developed and approved, “[t]he diverters shall
implement corrective actions in accordance with the corrective action plan, or cease
diverting water for frost protection.” (Regulation 862, subd. (c)(4).) Reinforcing this
ban, Regulation 862 declares, “The diversion of water in violation of this section,


                                              6
including the failure to implement the corrective actions included in any corrective action
plan developed by the governing body, is an unreasonable method of diversion and use
and a violation of Water Code section 100, and shall be subject to enforcement by the
board.” (Id., subd. (e).)
       In the resolution adopting Regulation 862, the Board stated the portion of the
regulation requiring corrective actions would not be implemented immediately. Instead,
the resolution establishes a schedule allowing for the collection and analysis of baseline
data during the first two and a half years following adoption.
       Regulation 862 was challenged in two petitions for a writ of mandate filed in
Mendocino and Sacramento Counties. The Mendocino County action was filed by
Rudolph H. Light and Linda Light, owners of 23 acres of vineyard in the affected area
that are crossed by a stream from which the Lights draw water for purposes of irrigation
and frost protection. The Sacramento County action was filed by a grower association,
three individuals, and a limited partnership (the Sacramento plaintiffs), all of whom either
grow grapes in the affected area or have members who do so.4 Both petitions alleged, for
a variety of reasons, that Regulation 862 would unlawfully interfere with plaintiffs’ use
of water drawn from the Russian River stream system. The petitions were consolidated
for decision in Mendocino County Superior Court. In February 2012, the trial court
stayed enforcement of Regulation 862 pending resolution of the litigation.
       The trial court later entered a 41-page decision finding the Board’s action unlawful
on the following grounds: (1) the Board exceeded its authority in adopting a regulation
that limited the use of water by riparian users; (2) the regulation violated the “rule of


       4
         The Sacramento plaintiffs are Russian River Water Users for the Environment,
an unincorporated association of Mendocino and Sonoma County residents and entities
interested in fruit and winery operations, Allan Nelson, a Sonoma County vineyard
owner, Billy Munselle, an Alexander Valley grape grower, Robert Terry Rosetti, a grape
and pear grower in Mendocino County, and Redwood Ranch and Vineyards, LP, which
owns vineyard land adjoining the Russian River. As a regular part of their business
operations, Munselle and Rosetti draw water from the Russian River stream system for
frost protection purposes.


                                              7
priority,” which governs the manner in which insufficient water is divided among users;
(3) the regulation improperly delegated regulatory authority to the WDMP’s; and (4) the
declaration of necessity for the regulation was not supported by substantial evidence.
Given its ruling, the trial court initially declined to rule on plaintiffs’ claims under the
California Environmental Quality Act (Pub. Resources Code, § 21000 et seq.; CEQA),
but in a subsequent order the court found several flaws in the environmental impact
report prepared in connection with Regulation 862. The court entered judgment directing
issuance of a peremptory writ of mandate requiring the Board to set aside its certification
of the environmental impact report and its adoption of Regulation 862.
        The Board has appealed the trial court’s judgment.
                                       II. DISCUSSION
A. Legal Background
        We begin with a summary of four areas of law that converge in the resolution of
plaintiffs’ claims.
        1. California’s Dual System of Water Rights and the Rule of Priority
        Ownership of California’s water is vested generally in the state’s residents, but
individuals and entities can acquire “water rights,” the right to divert water from its
natural course for public or private use. (Wat. Code,5 § 102; see generally United States
v. State Water Resources Control Bd. (1986) 182 Cal.App.3d 82, 100 (United States).)
California maintains a “dual system” of water rights, which distinguishes between the
rights of “riparian” users, those who possess water rights by virtue of owning the land by
or through which flowing water passes, and “appropriators,” those who hold the right to
divert such water for use on noncontiguous lands. (El Dorado Irrigation Dist. v. State
Water Resources Control Bd. (2006) 142 Cal.App.4th 937, 961 (El Dorado).) For
historical reasons, California further subdivides appropriators into those whose water




        5
            Unless otherwise indicated, subsequent statutory references are to the Water
Code.


                                               8
rights were established before and after 1914.6 Post-1914 appropriators may possess
water rights only through a permit or license issued by the Board, and their rights are
circumscribed by the terms of the permit or license. Riparian users and pre-1914
appropriators need neither a permit nor other governmental authorization to exercise their
water rights. (California Farm Bureau Federation v. State Water Resources Control Bd.
(2011) 51 Cal.4th 421, 428–429 (Farm Bureau).) Inevitably, given the nature of the
resource, “water rights are limited and uncertain. The available supply of water is largely
determined by natural forces.” (United States, at p. 104; see also Gray, The Uncertain
Future of Water Rights in California: Reflections on the Governor’s Commission Report
(2005) 36 McGeorge L. Rev. 43, 49–51 [discussing factors creating uncertainty in the
exercise and administration of water rights].)
       The differences between and among riparian users and appropriators become most
pronounced when the available supply of water is inadequate to satisfy the needs of all
those holding water rights. Under the “rule of priority,” which governs diversion in such
circumstances, the rights of riparian users are paramount. Although riparian users must
curtail their use proportionately among themselves in times of shortage, they are entitled
to satisfy their reasonable needs first, before appropriators can even begin to divert water.
(United States, supra, 182 Cal.App.3d at p. 104.) As a result, appropriators may be
deprived of all use of water when the supply is short. In turn, senior appropriators—
those who acquired their rights first in time—are entitled to satisfy their reasonable
needs, up to their full appropriation, before more junior appropriators become entitled to
any water. (Id. at pp. 104–105; North Kern Water Storage Dist. v. Kern Delta Water
Dist. (2007) 147 Cal.App.4th 555, 561.)




       6
        In 1913, the Legislature enacted the Water Commission Act, which, among other
provisions, required any new appropriations to occur by permit, issued by a predecessor
of the Board. Appropriations established prior to the Act’s effective date in late 1914
were grandfathered. (See generally State Water Resources Control Bd. Cases (2006)
136 Cal.App.4th 674, 741–742.)


                                              9
       2. The Rule of Reasonableness
       Water use by both riparian users and appropriators is constrained by the rule of
reasonableness, which has been preserved in the state Constitution since 1928. (Cal.
Const., art. X, § 2; hereafter Article X, Section 2.) Article X, Section 2 was a direct
response to a 1926 judicial decision, Herminghaus v. South. California Edison Co. (1926)
200 Cal. 81, in which the Supreme Court affirmed an injunction that prevented the
diversion of San Joaquin River water to Southern California. The court reasoned there
was no water to spare because riparian users of the river were entitled to receive its
“usual and ordinary flow,” which the court found to include even its floodwaters, of
which the users made little use. (Id. at pp. 90, 103.) The Constitution was amended two
years later effectively to overrule Herminghaus by adding what is now codified as
Article X, Section 2. (Joslin v. Marin Mun. Water Dist. (1967) 67 Cal.2d 132, 138
(Joslin).) Article X, Section 2 states, in relevant part: “The right to water or to the use or
flow of water in or from any natural stream or water course in this State is and shall be
limited to such water as shall be reasonably required for the beneficial use to be served,
and such right does not and shall not extend to the waste or unreasonable use or
unreasonable method of use or unreasonable method of diversion of water. Riparian
rights in a stream or water course attach to, but to no more than so much of the flow
thereof as may be required or used consistently with this section, for the purposes for
which such lands are, or may be made adaptable, in view of such reasonable and
beneficial uses . . . .” (Cal. Const., art. X, § 2.) As the Supreme Court recognized soon
after Article X, Section 2 was added, the rule limiting water use to that reasonably
necessary “appl[ies] to the use of all water, under whatever right the use may be
enjoyed.” (Peabody v. City of Vallejo (1935) 2 Cal.2d 351, 367–368 (Peabody).) The
rule of reasonableness is now “the overriding principle governing the use of water in
California.” (People ex rel. State Water Resources Control Bd. v. Forni (1976)
54 Cal.App.3d 743, 750 (Forni).)
       California courts have never defined, nor as far as we have been able to determine,
even attempted to define what constitutes an unreasonable use of water, perhaps because


                                             10
the reasonableness of any particular use depends largely on the circumstances. (Peabody,
supra, 2 Cal.2d at p. 368.) “What may be a reasonable beneficial use, where water is
present in excess of all needs, would not be a reasonable beneficial use in an area of great
scarcity and great need. What is a beneficial use at one time may, because of changed
conditions, become a waste of water at a later time.” (Tulare Dist. v. Lindsay-Strathmore
Dist. (1935) 3 Cal.2d 489, 567.) In this regard, the Joslin court commented, “Although,
as we have said, what is a reasonable use of water depends on the circumstances of each
case, such an inquiry cannot be resolved in vacuo isolated from statewide considerations
of transcendent importance. Paramount among these we see the ever increasing need for
the conservation of water in this state, an inescapable reality of life quite apart from its
express recognition in [Article X, Section 2].” (Joslin, supra, 67 Cal.2d at p. 140,
fn. omitted; see similarly In re Waters of Long Valley Creek Stream System (1979)
25 Cal.3d 339, 354 [“it appears self-evident that the reasonableness of a riparian use
cannot be determined without considering the effect of such use on all the needs of those
in the stream system [citation], nor can it be made ‘in vacuo isolated from statewide
considerations of transcendent importance’ ”].) Few decisions have ruled on the
reasonableness of a specific use of water, but in separate cases the Supreme Court has
concluded, essentially as self-evident, that the use of water for the sole purpose of
flooding the land to kill gophers and squirrels is unreasonable (Tulare Dist., at p. 568), as
is the use of floodwaters solely to deposit sand and gravel on flooded land (Joslin, at
p. 141).
       3. Public Trust Doctrine
       Existing alongside the rule of reasonableness is a second doctrine imposing at least
a potential limit on private uses of water. As the Supreme Court has explained that
doctrine, the state holds the navigable waterways in “public trust” for the benefit of state
residents. (National Audubon Society v. Superior Court (1983) 33 Cal.3d 419, 434, 437
(Audubon Society).) In Audubon Society, the plaintiffs challenged long-standing water
use permits issued by the Board that, by allowing the diversion of water from streams
feeding Lake Mono, had resulted in an environmentally destructive decrease in the lake’s


                                              11
level. In declining to reconsider the permits, the Board concluded it was required to
allocate all available water for beneficial use by appropriators, notwithstanding the
potential environmental harm such diversions would cause. (Id. at p. 427.) The Audubon
Society court required the Board to reconsider the permits, taking into account the public
trust doctrine. (Id. at pp. 446–447.) Although the doctrine originally protected navigable
waterways for the purposes of navigation, commerce, and fishing, Audubon Society
extended the geographic scope of the doctrine to non-navigable streams that feed
navigable waterways, and it expanded the purpose of the doctrine to the preservation of
water’s function as natural habitat. (Id. at pp. 434–435, 437; see Center for Biological
Diversity, Inc. v. FPL Group, Inc. (2008) 166 Cal.App.4th 1349, 1361 [“an important
purpose of the public trust over bodies of water is to protect the habitat for wildlife”].)
       In defining the role of the public trust doctrine in water rights policy, Audubon
Society recognized that “the public trust doctrine and the appropriative water rights
system administered by the Water Board developed independently of each other. Each
developed comprehensive rules and principles which, if applied to the full extent of their
scope, would occupy the field of allocation of stream waters to the exclusion of any
competing system of legal thought.” (Audubon Society, supra, 33 Cal.3d at p. 445.) In
bringing the two together, the court held the doctrine (1) prevents any party from
acquiring a vested right to appropriated water in a manner harmful to the interests
protected by the public trust; (2) “the Legislature, acting directly or through an authorized
agency such as the Water Board, has the power to grant usufructuary licenses that will
permit an appropriator to take water . . . , even though this taking does not promote, and
may unavoidably harm, the trust uses at the source stream”; and (3) “[t]he state has an
affirmative duty to take the public trust into account in the planning and allocation of
water resources, and to protect public trust uses whenever feasible.”7 (Audubon Society,
at pp. 445–446, fn. omitted.)

       7
        Although subsequent Supreme Court cases have acknowledged the public trust
doctrine, they have not elaborated on its role in California jurisprudence. (E.g.,
Environmental Protection Information Center v. California Dept. of Forestry & Fire

                                              12
       4. The Board
       The Board was created as the State Water Commission in 1913 to administer the
appropriation of water for beneficial purposes. As originally created, the Board had the
“limited role” of granting use rights to water that was not being applied to beneficial
purposes and was not otherwise appropriated. (Audubon Society, supra, 33 Cal.3d at
p. 442.) “[T]he function of the Water Board was restricted to determining if
unappropriated water was available; if it was, and no competing appropriator submitted a
claim, the grant of an appropriation was a ministerial act.” (Ibid.) The enactment of
Article X, Section 2, however, “radically altered water law in California and led to an
expansion of the powers of the board.” (Audubon Society, at p. 442.) Through
subsequent legislation and judicial decisions, “the function of the Water Board has
steadily evolved from the narrow role of deciding priorities between competing
appropriators to the charge of comprehensive planning and allocation of waters.” (Id. at
p. 444.)
       As currently constituted, the Board “has been granted broad authority to control
and condition water use, insuring utilization consistent with public interest.”
(Environmental Defense Fund, Inc. v. East Bay Mun. Utility Dist. (1977) 20 Cal.3d 327,
342 (EBMUD).) Its enabling statute describes the Board’s function as “to provide for the
orderly and efficient administration of the water resources of the state” and grants it the
power to “exercise the adjudicatory and regulatory functions of the state in the field of
water resources.” (§ 174.) In that role, the Board is granted “any powers . . . that may be
necessary or convenient for the exercise of its duties authorized by law” (§ 186,
subd. (a)), including the power to “make such reasonable rules and regulations as it may
from time to time deem advisable . . . .” (§ 1058.) Among its other functions, “the . . .


Protection (2008) 44 Cal.4th 459, 515; In re Bay-Delta etc. (2008) 43 Cal.4th 1143,
1154.) Audubon Society remains the most recent Supreme Court authority governing
application of the doctrine in this context. A more recent discussion is found in our
decision in Citizens for East Shore Parks v. State Lands Com. (2011) 202 Cal.App.4th
549, 570–571, 573–578.)


                                             13
board shall take all appropriate proceedings or actions before executive, legislative, or
judicial agencies to prevent waste, unreasonable use, unreasonable method of use, or
unreasonable method of diversion of water in this state.” (§ 275.) The Board’s authority
to prevent unreasonable or wasteful use of water extends to all users, regardless of the
basis under which the users’ water rights are held. (Farm Bureau, supra, 51 Cal.4th at
p. 429.)
B. Validity of Regulation 862
       In contending Regulation 862 is invalid, plaintiffs argue (1) the Board lacks the
authority to enact regulations governing the unreasonable use of water, (2) the Board
lacks the authority to limit the use of water by riparian and pre-1914 appropriators, and
(3) Regulation 862 improperly violates the rule of priority. Whether a particular
regulation is within the scope of authority conferred by the Legislature on an
administrative agency is a legal issue we review de novo. (Yamaha Corp. of America v.
State Bd. of Equalization (1998) 19 Cal.4th 1, 11, fn. 4; Southern California Gas Co. v.
South Coast Air Quality Management Dist. (2011) 200 Cal.App.4th 251, 268.)
       1. The Board’s Authority to Enact Regulations Governing the Unreasonable
          Use of Water
       The Board characterized the regulatory premise of Regulation 862 as follows: “a
diversion of water that is harmful to salmonids is an unreasonable use of water if the
diversion can be managed to avoid the harm.” (State Water Resources Control Bd.,
Notice of Preparation and Public Scoping Meeting Mem. (Oct. 27, 2010) p. 2.) In finding
the Board lacked the authority to enact Regulation 862, the trial court recognized the
Board had regulatory authority over the unreasonable use of state waters. It held,
however, that this authority was limited, at least as to riparian users, to pursuing
enforcement actions in the courts against allegedly unreasonable users, rather than
enacting regulations to preclude unreasonable use.
       Neither decisional law nor the governing statutes support the trial court’s limited
vision of the Board’s regulatory authority. As noted above, the Board is charged with
acting to prevent unreasonable and wasteful uses of water, regardless of the claim of right


                                             14
under which the water is diverted. (§ 275; Farm Bureau, supra, 51 Cal.4th at p. 429.)
The Board’s authority to enact regulations in furtherance of this purpose was addressed
and upheld nearly 40 years ago in Forni. In that case, the Board had adopted a
regulation, then codified as section 659 of title 23 of the California Administrative Code,
which held, “ ‘diversion of water from the Napa River after March 15 for frost protection
except to replenish water stored in reservoirs prior to March 15 is an unreasonable
method of diversion within the meaning of [Article X, Section 2] and Section 100 of the
Water Code.’ ” The regulation was motivated by a lack of adequate water to satisfy the
frost protection demands of all users.8 (Forni, supra, 54 Cal.App.3d at pp. 748 & 752,
fn. 4.) Based on that regulation, the Board brought an action to enjoin certain vineyard
owners from drawing water from the river for purposes of frost protection. (Id. at
p. 747.) The defendants were granted summary judgment on the ground the Board lacked
the authority to prohibit or limit the use of water by riparian users. (Id. at p. 748.) In
reversing the trial court’s judgment invalidating the regulation, the court rejected the
argument, made on several grounds, that the Board lacked the authority to interfere with
water use by riparian users. (Forni, at pp. 751–752.) The court then upheld the Board’s
power to enact a regulation governing reasonable use. Without extensive discussion, the
court concluded the Board had not exceeded its authority in enacting the regulation
because, “[p]roperly construed, section 659 amounts to no more than a policy statement
which leaves the ultimate adjudication of reasonableness to the judiciary.” (Id. at p. 752.)
       Plaintiffs rightly point out that, despite Forni’s refusal to invalidate the regulation,
its resolution of the issue was not a ringing endorsement of the Board’s power to enact
regulations governing the unreasonable use of water. In effect, Forni chose to treat the
regulation as an advisory statement of policy that left to the courts the ultimate authority

       8
         The regulation is now codified as California Code of Regulations, title 23,
section 735 and states, “all diversions of water from the [Napa River] stream system
between March 15 and May 15 determined to be significant by the board or a court of
competent jurisdiction shall be considered unreasonabl[e] and a violation of Water Code
Section 100 unless controlled by a watermaster administering a board or court approved
distribution program.” (Id., subd. (a).)


                                              15
to determine whether a particular use of water was reasonable. (Forni, supra,
54 Cal.App.3d at p. 752.) Of course, to the extent the bald declaration of
unreasonableness in former section 659 constituted a valid “policy statement” under
Forni, Regulation 862 is similarly valid. At a minimum, Forni’s holding would require a
reversal of the trial court’s invalidation of the regulation on the issue of authority.
       Yet to the extent Forni’s ruling was based on the implicit rationale that only the
judiciary has the power to declare a particular water use unreasonable, we conclude Forni
construed the Board’s authority too narrowly. Subsequent judicial decisions have
rejected the contention that the judiciary is vested with sole authority over unreasonable
use, most forcefully California Trout, Inc. v. State Water Resources Control Bd. (1989)
207 Cal.App.3d 585 (California Trout). At issue in California Trout was the validity of a
Board-issued use permit conditioned on compliance with a state statute requiring the
owner of any dam to “allow sufficient water at all times to pass . . . around or through the
dam, to keep in good condition any fish that may be planted or exist below the dam.”
(Fish & G. Code, § 5937.) Among other arguments, a plaintiff contended “the
Legislature may not impose a categorical priority for one use of water because
reasonableness of use requires comparison of contending alternative uses which is an
adjudicative question that cannot be constrained by a statutory rule.” (California Trout,
at p. 622.) The court rejected the contention the Legislature lacked the power to enact
broad rules governing reasonableness, using an analogy to the doctrine of reasonable
conduct in tort law. As the court explained, “it is often asserted that ‘[w]hat constitutes a
reasonable use or method of diversion is ordinarily a question of fact.’ [Citation.]
Actually, since what occurs is development of a standard of reasonableness on the facts
of the case it should be described as a making of law for the particular case. [Citation.]
The typical example of such a process is case-by-case determination of the standard of
reasonable care in the law of tort. However, the fact that, ordinarily, the standard of
reasonableness is fixed ad hoc does not impel the view that the Legislature has no power
to fashion rules concerning reasonableness, e.g., by enacting statutory safety obligations
which become the basis of negligence per se.” (Id. at p. 624.) After analyzing the text


                                              16
and judicial construction of Article X, Section 2, the court concluded, “there is ‘broad
legislative authority for the conservation and regulation of scarce water resources . . . .’
[Citation.] That authority is sufficient to authorize the Legislature to enact statutes which
determine the reasonable uses of water.” (California Trout, at p. 625.)9
       If, as California Trout holds, the Legislature has the power to enact general rules
governing the reasonable use of water, the Board has a similar regulatory authority. The
Water Code authorizes the Board, in carrying out its statutory duty to administer the
state’s water resources, to “exercise the adjudicatory and regulatory functions of the
state.” (§ 174.) In that role, the Board is granted “any powers . . . that may be necessary
or convenient for the exercise of its duties authorized by law” (§ 186, subd. (a)),
including the authority to “make such reasonable rules and regulations as it may from
time to time deem advisable . . . .” (§ 1058.) Given the Board’s statutory charge to
“prevent waste, unreasonable use, unreasonable method of use, or unreasonable method
of diversion of water in this state” (§ 275) and the recognized power of the Legislature to
pass legislation regulating reasonable uses of water (California Trout, supra,
207 Cal.App.3d at pp. 624–625), the Board’s grant of authority to “exercise the . . .
regulatory functions of the state” (§ 174) necessarily includes the power to enact
regulations governing the reasonable use of water.
       The Supreme Court has recognized as much, describing the Board’s regulatory
authority in the broadest terms. “The Legislature, consistent with its authority under
[Article X, Section 2], has established a thorough statutory system insuring reasonable
water allocation and safeguarding water purity, commensurate in scope with the

       9
         Amicus curiae California Farm Bureau Federation deceptively characterizes
California Trout as declaring “clearly established law” that “ ‘what is a reasonable or
unreasonable use of water is a judicial question to be determine in the first instance by the
trial court.’ ” (California Trout, supra, 207 Cal.App.3d at p. 623.) In fact, California
Trout rejected that position, finding the plaintiff’s contention that “the question of
reasonableness invariably must be resolved ad hoc, adjudicatively” to be “unsupported by
apposite authority and insupportable in reason and legal doctrine.” (Id. at p. 624.) As the
quote in the text demonstrates, the holding of California Trout was precisely the opposite
of the holding ascribed to it by amicus curiae.


                                              17
constitutional provision. [Citation.] The statutes vest the [Board] with full authority to
‘exercise the adjudicatory and regulatory functions of the state in the field of water
resources.’ [Citations.] It has been granted broad authority to control and condition
water use, insuring utilization consistent with public interest. [Citation.] This authority
includes protection of the environment. [Citation.] The [Board’s] powers extend to
regulation of water quality and prevention of waste. [Citations.] It has adopted
administrative regulations to prevent waste and unreasonable use.” (EBMUD, supra,
20 Cal.3d at pp. 341–342, italics added.) While the EBMUD decision did not address the
validity of the regulations to which it referred, the court did not hesitate in recognizing
them as an exercise of the Board’s authority. (See similarly Audubon Society, supra,
33 Cal.3d at p. 449 [“we have discerned a legislative intent to grant the Water Board a
‘broad,’ ‘open-ended,’ ‘expansive’ authority to undertake comprehensive planning and
allocation of water resources”].)
       In arguing the Board’s authority in this area is limited to enforcement actions,
plaintiffs rely in part on the text of section 275, the statutory provision directly addressing
unreasonable use, which instructs the Board to “take all appropriate proceedings or
actions before executive, legislative, or judicial agencies to prevent waste, unreasonable
use, unreasonable method of use, or unreasonable method of diversion of water in this
state.” Conspicuously missing, plaintiffs contend, is any reference to the exercise of rule-
making authority. While we acknowledge the absence, we do not construe section 275 as
a limitation on the Board’s authority in the area of unreasonable use. As discussed
above, the remaining provisions of the Water Code, as construed by decisional authority,
vest in the Board broad adjudicatory and regulatory power and suggest the Board’s
regulatory authority is coincident with that of the Legislature. There is no reason to
conclude the Legislature intended the Board to have less or restricted authority in
enforcing the constitutional mandate of Article X, Section 2.
       A contention similar to plaintiffs’ was rejected in Imperial Irrigation Dist. v. State
Water Resources Control Bd. (1986) 186 Cal.App.3d 1160, in which the Board
conducted hearings, found the plaintiff’s failure to implement water conservation


                                              18
measures to constitute an unreasonable use of water, and ordered it to undertake various
measures. (Id. at p. 1163.) On appeal, the plaintiff challenged the Board’s authority to
adjudicate the issue of reasonable use, contending the Board was required by section 275
to rely on the courts in carrying out its mandate to prevent the unreasonable use of water.
After reviewing the various statutes conferring regulatory authority on the Board, the
court concluded section 275 was intended to augment the Board’s powers, rather than
limit them: “No case has construed section 275 as a limitation on the Board’s
adjudicatory power. . . . [¶] A case decided since the trial court’s hearing in this matter
correctly cites section 275 when viewed together with [Article X, Section 2] and
section 1050, as authority for the proposition the Board has ‘the separate and additional
power to take whatever steps are necessary to prevent unreasonable use or methods of
diversion.’ [Citation.] . . . Section 275 is not to be construed as a limitation on the
Board’s adjudicatory authority, but rather as a statute granting separate, additional power
to the Board.” (Id. at pp. 1169–1170.) In the same manner, we conclude section 275
does not limit the Board’s authority under section 1058 to issue appropriate regulations.
       Particularly in these circumstances, there is a practical reason for recognizing the
Board’s authority to issue regulations. The problem addressed by Regulation 862 is the
abrupt drop in stream levels that occurs when a large number of users simultaneously
activate sprinklers that draw a large volume of water. No one doubts the use of sprinkled
water to prevent crop frost damage is a beneficial one. Whether it is also a reasonable
use, the Board has determined, depends upon whether “the diversion can be managed to
avoid the harm” to salmonids. It appears that in many, or perhaps most circumstances,
diversion for frost protection purposes from the Russian River stream system is
biologically harmless. Yet on those occasions when it might be damaging, it has the
potential to inflict long-lasting damage on already fragile salmon populations.
Restricting the Board to post-event litigation deprives it of any effective regulatory
remedy, since the damage will have been done and the critical circumstances may not
arise again for months or years. It is difficult to imagine what effective relief a court
could grant, other than a broad and inflexible injunction against future diversion for


                                              19
purposes of frost protection, a ruling that would be in the interests neither of the enjoined
growers nor the public. Efficient regulation of the state’s water resources in these
circumstances demands that the Board have the authority to enact tailored regulations.10
       2. Regulation of Riparian Users and Pre-1914 Appropriators
       In contending the Board exceeded its authority, plaintiffs also cite the time-
honored exemption of riparian users and pre-1914 appropriators from the permitting
authority of the Board. (E.g., Farm Bureau, supra, 51 Cal.4th at p. 429.) While such
users cannot be required to obtain permits as a condition of exercising their right to
divert, that does not mean their use of California’s waters is free from Board regulation.
“[N]o water rights are inviolable; all water rights are subject to governmental regulation.”
(United States, supra, 182 Cal.App.3d 82, 106.) The Supreme Court recognized as much
in Farm Bureau; immediately after noting the Board “has no permitting or licensing
authority over riparian . . . rights, or over appropriative rights acquired before 1914,” the
court observed the Board “does have authority to prevent illegal diversions and to prevent
waste or unreasonable use of water, regardless of the basis under which the right is held.”
(Id. at p. 429, fns. omitted.) That the Board cannot require riparian users and pre-1914
appropriators to obtain a permit before making reasonable beneficial use of water does
not mean the Board cannot prevent them from making unreasonable use. Any other rule
would effectively read Article X, Section 2 out of the Constitution.
       Plaintiffs argue that Regulation 862 effectively imposes a permit requirement,
since it conditions their use of water on compliance with standards developed by a
WDMP. The argument proves too much, since its acceptance would preclude any
regulation of water use by riparian users and pre-1914 appropriators. Preventing these
users from the unreasonable use of water necessarily requires the imposition of limits on

       10
          Our holding is, of course, limited to resolution of the facial challenge presented
here: in general terms, the Board has the authority to find unreasonable a diversion of
water for frost protection if that diversion is inconsistent with the public trust by creating
a significant risk of salmonid mortality. Because no WDMP’s have been approved, let
alone violated, we have no basis for finding any particular failure to comply with a
WDMP to be an unreasonable use of water.


                                              20
that use by the Board. Limited and particularized prohibitions designed to prevent
unreasonable use are different from, and by no means legally equivalent to, the
comprehensive regulation embodied in a water use permit, which, as an allocation of
“excess water,” typically limits the user’s rights without regard to the reasonableness of
use. (See City of Pasadena v. City of Alhambra (1949) 33 Cal.2d 908, 925–926.)
       The Lights contend the “vested rights” doctrine prevents the Board from
“redefining” an existing beneficial use as unreasonable. The position has been rejected
repeatedly. It is now recognized that, since enactment of Article X, Section 2, “there can
no longer be any property right in the unreasonable use of water.” (In re Waters of Long
Valley Creek Stream System, supra, 25 Cal.3d at p. 354.) What constitutes an
unreasonable use of water changes with circumstances, including the passage of time.
(Joslin, supra, 67 Cal.2d at p. 140; Tulare Dist. v. Lindsay-Strathmore Dist., supra,
3 Cal.2d at p. 567 [“What is a beneficial use at one time may, because of changed
conditions, become a waste of water at a later time.”].) Thus, the extent of a particular
user’s vested right to use water similarly may change. Riparian users’ vested water rights
extend only to reasonable beneficial water use, which is determined at the time of use.11
       3. Violation of the Rule of Priority
       The Lights additionally argue that, whatever the scope of the Board’s regulatory
authority, it does not have the power “to adopt a definition that prohibits a ‘beneficial
use,’ even though the amount of water being used for that beneficial use is no more than
minimally required, in order to protect another ‘beneficial use’ to which it ascribes higher




       11
          The Lights also argue the Board exceeded its authority because various statutes
state they do not grant the Board authority to regulate water use “not otherwise subject to
regulation” by the Board. (E.g., § 1831, subd. (e).) Because Regulation 862 concerns
regulation of the unreasonable use of water, it does not concern a use not otherwise
subject to the Board’s jurisdiction. (See Article X, Section 2 [“Riparian rights in a stream
or water course attach to, but to no more than so much of the flow thereof as may be
required or used consistently with this section . . . .”].) As noted in the text, precisely
what type of water use is unreasonable varies with time and circumstance.


                                              21
priority.” Essentially on this basis, the parties characterize the Board’s regulation as a
violation of the rule of priority.
       In analyzing this contention, we start with the premise that the supply of water in
California is variable and at times insufficient to supply all possible beneficial uses. As
the circumstances of this appeal demonstrate, this may be true on a temporary and
localized basis, as well as on a more global one. When the supply of water in a particular
stream system is insufficient to satisfy all beneficial uses, water rights users must curtail
their use. As discussed above, the rule of priority dictates that riparian users are satisfied
first, but when the supply runs sufficiently short, even riparian users must curtail their
beneficial use proportionately. (United States, supra, 182 Cal.App.3d at p. 104.)
       So long as the only water uses involved are those governed by common law and
statutory water rights, the Lights’ contention might have force. When the supply of water
is insufficient to satisfy all persons and entities holding water rights, it is ordinarily the
function of the rule of priority to determine the degree to which any particular use must
be curtailed. Yet even in these circumstances, the Board has the ultimate authority to
allocate water in a manner inconsistent with the rule of priority, when doing so is
necessary to prevent the unreasonable use of water. (El Dorado, supra, 142 Cal.App.4th
937, 966.) Because “ ‘no one can have a protectible interest in the unreasonable use of
water’ [citation] . . . when the rule of priority clashes with the rule against unreasonable
use of water, the latter must prevail.” (Ibid.)
       This case, moreover, involves more than traditional water rights. As the Supreme
Court held in Audubon Society, no party can acquire a vested right to appropriate water in
a manner harmful to public trust interests and the state has “an affirmative duty” to take
the public trust into account in regulating water use by protecting public trust uses
whenever feasible. (Audubon Society, supra, 33 Cal.3d at pp. 446–447.) Although the
Audubon Society court considered the public trust doctrine only in relation to permitted
appropriative water rights, subsequent decisions have assumed the doctrine applies as
well in the context of riparian and pre-1914 appropriator rights. (United States, supra,
182 Cal.App.3d at p. 106 [in Audubon Society, “the court determined that no one has a


                                               22
vested right to use water in a manner harmful to the state’s waters”]; El Dorado, supra,
142 Cal.App.4th at p. 966 [“when the public trust doctrine clashes with the rule of
priority, the rule of priority must yield”].)
       In holding that Regulation 862 does not violate the rule of priority, our decision
extends only to the regulation’s potential for allocating water between the beneficial
public trust use of maintaining stream levels to avoid salmonid deaths and the beneficial
use of diversion for frost protection by water rights holders. As between particular rights
holders, “[e]very effort . . . must be made to respect and enforce the rule of priority. A
solution to a dispute over water rights ‘must preserve water right priorities to the extent
those priorities do not lead to unreasonable use.’ ” (El Dorado, supra, 142 Cal.App.4th
at p. 966.) The Sacramento plaintiffs argue this principle is violated because “[t]he
regulation broadly declares unreasonable all water used for frost protection purposes in
two counties, without consideration of the priority of individual’s water rights.” This
badly misstates the import of the regulation. Regulation 862 does not declare any
specific diversion of water for frost protection unreasonable, much less all such use.
Frost protection diversion is unreasonable only if it occurs in violation of a WDMP. As
among individual water rights holders, Regulation 862 requires WDMP’s to respect the
rule of priority in assigning corrective actions. (Id., subd. (c)(4).)
       While it is possible, as the Sacramento plaintiffs argue, that the decentralized
system of WDMP’s creates a risk of priority rule violations, such concerns are premature
until WDMP’s have been put into effect. This is a facial challenge to Regulation 862,
and we hold only that there is no basis for finding Regulation 862, on its face, violates the
rule of priority. A determination of whether specific regulatory measures adopted by the
WDMP’s violate the rule of priority, and whether any such violation is justified by the
Board’s responsibilities under Article X, Section 2, must await implementation of the
regulation.12

       12
         The Sacramento plaintiffs argue at length the Board should have adopted
substantive regulations requiring attenuation of use first by junior appropriators and
deferring attenuation by users with priority. While this is certainly one form substantive

                                                23
C. Delegation of Regulatory Authority to WDMP Governing Bodies
       The trial court concluded Regulation 862 improperly delegated the regulatory
authority of the Board to WDMP’s, reasoning the requirement of the section that the
governing body be “capable of ensuring that the requirements of the program are met”
(Regulation 862, subd. (b)) means enforcement of the WDMP’s has been delegated to the
governing boards. The court also concluded the section constituted an improper
delegation of legislative authority because “[d]eclaring the use of water for frost
protection an unreasonable use of water is a fundamental shift in water policy in this
state.” We review the constitutional issue of unlawful delegation de novo. (People ex
rel. Lockyer v. Sun Pacific Farming Co. (2000) 77 Cal.App.4th 619, 632 (Sun Pacific).)
       There is a tension when private industry shares responsibility for the governmental
regulation of its commercial activities. On the one hand, members of the industry are
well positioned to understand the regulatory needs and the impact of regulation on their
business activities. In this respect, they are ideal partners in the formulation of
appropriate regulations. Perhaps for this reason, it has never been held that the mere
involvement of regulated private parties in the making of administrative regulations
constitutes an improper delegation of governmental authority. On the other hand, by
involving members of the regulated industry the agency runs the risks associated with the
fox guarding the henhouse. As a result, there is “a tight line between lawful and unlawful
delegation of regulatory authority.” (International Assn. of Plumbing etc. Officials v.
California Building Stds. Com. (1997) 55 Cal.App.4th 245, 253 (Plumbing etc. Officials)
[holding that model building codes developed by private parties cannot become binding
regulations without agency review and approval].)
       “To put it simply, the Legislature could not lawfully grant the power to make laws
to a private entity.” (Plumbing etc. Officials, supra, 55 Cal.App.4th at p. 253.) While, as


regulation could have taken, the Board’s decision to leave such substantive regulation to
the WDMP’s did not render the regulation in excess of the Board’s authority, since the
regulation requires priorities to be respected within individual WDMP’s when corrective
actions are mandated. (Regulation 862, subd. (c)(4).)


                                              24
illustrated in Plumbing etc. Officials, private entities can formulate and suggest potential
regulation, the doctrine of unlawful delegation requires the Legislature or a regulatory
agency to exercise the final say over whether any particular regulation becomes law. In
addition, the Legislature cannot “delegat[e] . . . regulatory power to agencies composed
of interested members of the regulated industries without imposing standards or
safeguards adequate to prevent abuse. Absent the required safeguards, such grants of
authority constitute unconstitutional delegations of legislative power.” (Dunn-Edwards
Corp. v. South Coast Air Quality Management Dist. (1993) 19 Cal.App.4th 536, 545–
546, fn. 5; see Bayside Timber Co. v. Board of Supervisors (1971) 20 Cal.App.3d 1, 11.)
       The delegation of authority to the WDMP governing bodies under Regulation 862
is not materially different from the type of delegation found lawful in Sun Pacific. The
defendant in Sun Pacific was a citrus grower that concededly harbored diseased trees in
its operations. When the state brought an action in the name of the local citrus pest
control district to remove the diseased trees, the defendant challenged the
constitutionality of the delegation of power to the district. (Sun Pacific, supra,
77 Cal.App.4th at p. 625.) Citrus pest control districts are established pursuant to state
law for more effective control and eradication of disease. They may be organized by the
local county boards of supervisors upon the petition of the owners of a majority of citrus
growing acreage in a district. The districts are governed by a five-person board of local
growers, required to formulate a plan for pest control and eradication, and granted
various powers to effectuate the program. (Id. at p. 627.) In considering the lawfulness
of this broad delegation, the court noted, “ ‘[a]n unconstitutional delegation of authority
occurs only when a legislative body (1) leaves the resolution of fundamental policy issues
to others or (2) fails to provide adequate direction for the implementation of that
policy.’ ” (Id. at p. 633.) In rejecting the argument “self-interested citrus growers” who
comprise a district’s board unlawfully “set policy,” the court held that the Legislature had
“made basic policy decisions with respect to the control and eradication of citrus pests,
through the best known and accepted methods,” leaving only the implementation of that
policy to growers. (Id. at pp. 633, 634.) In addition, the Legislature included “specific


                                             25
standards and safeguards . . . in the statute for both the formation of the pest control
districts and the exercise of their authority” to protect against the districts “exercising
their regulatory power arbitrarily.” (Id. at p. 634.)
       Similarly, in formulating Regulation 862, the Board clearly set out the
fundamental purposes of the WDMP’s: to develop and implement methods for
monitoring the level of the affected watercourses, determining when that level poses a
threat to young salmon, and responding with “corrective actions” to reduce a threat once
detected. (Regulation 862, subds. (b), (c)(2)–(4).) It then established detailed standards
for the manner in which the WDMP governing bodies are to monitor stream levels and
the type of corrective measures that can be instituted to prevent sudden decreases in water
level. (Ibid.) Finally, the Board placed itself between the governing bodies and the
regulated growers. No program developed by a governing body will become effective—
will acquire the force of law—until it has been approved by the Board, and that approval
must be sought annually. Nothing more was required to prevent an unlawful delegation
of authority.13
       Unlike the trial court, we do not construe Regulation 862 as delegating
enforcement authority to the governing bodies. Read in context, the requirement a
governing body be “capable of ensuring that the requirements of the program are met”
(Regulation 862, subd. (b)) means only the governing body must have the organization
and financial resources sufficient to develop a program, monitor its implementation, and
comply with the reporting requirements—in other words, be capable of administering a
WDMP. The statute is clear that the failure to comply with a WDMP, once it has been
approved, “shall be subject to enforcement by the board,” not the WDMP.
(Regulation 862, subd. (e).) The enforcement obligation of the WDMP’s governing body

       13
          The trial court was concerned that an improper delegation of authority had
occurred because a WDMP could require costly and intrusive regulatory steps of
diverters. While it is possible that individual WDMP’s will find it necessary to require
such corrective actions, their imposition is authorized by the Board in subdivision (c)(4)
of Regulation 862. Further, no corrective actions can be imposed except under the terms
of a WDMP, which must be approved in advance annually by the Board.


                                              26
is limited to reporting an uncooperative diverter to the Board. (Regulation 862,
subd. (c)(5)(E).) While it is true, as the Sacramento plaintiffs argue, that the governing
bodies will decide which growers must take corrective actions at any given time, those
decisions must be made in accordance with the WDMP, which in turn must be approved
by the Board. The role of the governing body is therefore the administration of a Board-
approved policy.14
       The trial court’s conclusion that the issue of balancing water use for frost
protection against water needs for the protection of wildlife is novel and “fundamental”
was erroneous, both conceptually and factually. The Board first declared the use of water
for frost protection to be unreasonable at least as early as Forni, decided in 1976.
Moreover, the truly fundamental issue was decided by the Legislature over a half-century
ago when it enacted section 1243 and amended section 1257. The former declares “[t]he
use of water for recreation and the preservation and enhancement of fish and wildlife
resources is a beneficial use of water” (Stats. 1959, ch. 2048, § 1, p. 4742), while the
latter similarly characterizes “preservation and enhancement of fish and wildlife” as a
beneficial use (Stats. 1959, ch. 2048, § 2, p. 4742). These sections represent a Legislative
declaration that the welfare of wildlife is a beneficial use on a par with the type of
commercial use that has traditionally been recognized as beneficial. Because, as
discussed above, the responsibility of the Board is to regulate the use of water for



       14
          Amicus curiae Northern California Water Association urges us to invalidate
Regulation 862 because the use of multiple, independent WMDP governing bodies
composed of self-interested members of the industry to regulate frost protection diversion
is a bad idea that will, in very general terms, create more problems than it solves. They
describe an alternative, voluntary approach that has worked well under different
circumstances in the Sacramento-San Joaquin Delta. While amicus curiae’s observations
about the structure of Regulation 862 might well be accurate, we have no power to
second-guess the wisdom of the Board’s manner of regulation, at least so long as it is not
arbitrary and capricious. No party to the appeal challenged per se the diversified, self-
regulatory structure of Regulation 862 in the briefs. Counsel for the Sacramento
plaintiffs did characterize the structure of Regulation 862 as a “train wreck” at oral
argument, but we take the comment to be rhetoric rather than legal argument.


                                             27
beneficial purposes, balancing the use of water for frost protection against its use for
salmon habitat is simply an application of this fundamental policy decision.15
       The Lights contend section 1243 actually expresses a Legislative preference for
“riparian rights over fish,” based on the concluding sentence of the statute. Although
section 1243 instructs the Board to “take into account, whenever it is in the public
interest, the amounts of water required for recreation and the preservation and
enhancement of fish and wildlife resources” when “determining the amount of water
available for appropriation for other beneficial uses,” it ends with the statement, “This
section shall not be construed to affect riparian rights.”16 In understanding the
Legislature’s intent, it is important to recognize the context of section 1243, which is
codified in the part of the Water Code dealing with the Board’s authority to issue permits
and in an article defining beneficial uses, which begins with the declaration that such uses
are a prerequisite for the granting of such a permit. (§ 1240.) Given this context, we
interpret the final sentence in section 1243 to constitute a reaffirmation of the freedom of
riparian users from the permitting authority of the Board, rather than a general declaration
that the rights of riparian users are paramount to the preservation of water as wildlife
habitat.17

       15
         For the same reason, we reject the Lights’ contention that the adoption of
Regulation 862 constituted a violation of the separation of powers doctrine because it left
to the Board the resolution of a “ ‘truly fundamental issue.’ ” (Bayside Timber Co. v.
Board of Supervisors, supra, 20 Cal.App.3d 1, 11.)
       16
          Section 1243 now reads in full: “The use of water for recreation and
preservation and enhancement of fish and wildlife resources is a beneficial use of water.
In determining the amount of water available for appropriation for other beneficial uses,
the board shall take into account, whenever it is in the public interest, the amounts of
water required for recreation and the preservation and enhancement of fish and wildlife
resources. [¶] The board shall notify the Department of Fish and Game of any application
for a permit to appropriate water. The Department of Fish and Game shall recommend
the amounts of water, if any, required for the preservation and enhancement of fish and
wildlife resources and shall report its findings to the board. [¶] This section shall not be
construed to affect riparian rights.”
       17
         Section 1257, which similarly characterizes habitat preservation as a beneficial
water use, contains no language regarding riparian uses.

                                             28
       The Lights also argue that allowing the WDMP’s to develop their own regulations
constitutes an unlawful delegation of the Board’s responsibilities under Schecter v.
County of Los Angeles (1968) 258 Cal.App.2d 391 (Schecter). Schecter involved a
dispute between the county’s civil service commission and its board of supervisors over
job classifications in the sheriff’s department. Pursuant to a commission rule requiring its
chief staff member to develop job classifications, subject to the approval of the
commission, the chief recommended to the commission the consolidation of certain
sheriff’s department job classifications. The commission rejected the chief’s
recommendation, instead adopting its own, different classifications. When the
commission’s order was sent to the board of supervisors for adoption, the board refused,
in effect arguing the commission’s rule permitted it only to accept or reject the chief’s
recommendation, rather than to develop classifications on its own initiative. (Id. at
pp. 393–396.) The court rejected the board’s position, finding the board’s interpretation
of the regulation to constitute an improper delegation of the commission’s authority to its
staff member. While the commission could rely on employees to “ ‘investigate and
report the facts and their recommendation’ ” and to draft orders in the first instance, the
court held, the members of the commission were required to exercise their own discretion
in approving a final order. (Id. at pp. 396–397.) Accordingly, the court affirmed the trial
court’s order requiring the board to adopt the commission’s classifications.
       As is evident from this description, Schecter does not suggest that an unlawful
delegation occurred here. In the same way that the civil service commission could use its
employees to investigate and draft a proposed classification order, the Board can rely on
WDMP’s to organize and draft programs. So long as the Board exercises its independent
discretion in evaluating those programs, no unlawful delegation has occurred. The
requirement of Regulation 862 that the Board approve any program implicitly requires
just such an exercise of independent discretion.18

       18
         The Lights also contend Schecter stands for the principle that “power [that] is
delegated by the people to the Legislature [in Article X, Section 2] . . . cannot be re-
delegated by the Legislature to the Board.” Schecter, which addressed an issue of local

                                             29
D. The Necessity for Regulation 862
       The trial court also found no substantial evidence to support the Board’s finding of
regulatory necessity for Regulation 862, concluding the Board had not collected
sufficient data to demonstrate the need for the regulation, particularly in light of the
purported success of voluntary efforts at mitigating the problem.
       Government Code section 11350, the statute governing judicial review of
administrative regulations, states a regulation “may” be declared invalid if “[t]he
agency’s determination that the regulation is reasonably necessary to effectuate the
purpose of the statute, court decision, or other provision of law that is being
implemented, interpreted, or made specific by the regulation is not supported by
substantial evidence.” (Id., subd. (b)(1); see also Gov. Code, § 11342.2 [regulation valid
only if it is “reasonably necessary to effectuate the purpose” of the statute it
implements].) “ ‘[Q]uasi-legislative rules . . . represent[] an authentic form of substantive
lawmaking: Within its jurisdiction, the agency has been delegated the Legislature’s
lawmaking power. [Citations.] . . . When a court assesses the validity of such rules, the
scope of its review is narrow. . . .’ [Citations.] When a regulation is challenged on the
ground that it is not ‘reasonably necessary to effectuate the purpose of the statute,’ our
inquiry is confined to whether the rule is arbitrary, capricious, or without rational basis
[citation] and whether substantial evidence supports the agency’s determination that the
rule is reasonably necessary [citation].” (Western States Petroleum Assn. v. Board of
Equalization (2013) 57 Cal.4th 401, 415.) “In determining whether [an agency’s
decision] was supported by substantial evidence, we resolve all conflicts in favor of the
[agency], indulging in all legitimate and reasonable inferences from the record. . . . When
two or more inferences can be reasonably deduced from those facts, the reviewing court


law, did not involve any delegation of constitutionally derived authority, nor did it use the
term “re-delegation.” We are not aware of any general legal prohibition on the
Legislature’s delegation of duties granted under the state Constitution to administrative
agencies. On the contrary, because the Legislature does not engage in the administration
of the state’s laws once enacted, it has little choice but to “re-delegate” such duties.


                                              30
has no power to substitute its deductions for those of the fact finder.” (Associated
Builders & Contractors, Inc. v. San Francisco Airports Com. (1999) 21 Cal.4th 352,
374.) “ ‘[R]easonable necessity . . . generally does implicate the agency’s expertise;
therefore it receives a much more deferential standard of review.’ ” (California Assn. of
Medical Products Suppliers v. Maxwell-Jolly (2011) 199 Cal.App.4th 286, 315.) In
reviewing a finding of reasonable necessity, our task “is the same as the trial court’s: The
appellate court reviews the agency’s action, not the trial court’s decision; in that sense
appellate judicial review . . . is de novo.” (Vineyard Area Citizens for Responsible
Growth, Inc. v. City of Rancho Cordova (2007) 40 Cal.4th 412, 427.)
       Regulation 862 was enacted to protect salmonids in the Russian River stream
system from stranding mortality due to sudden drops in water level during the late spring
and early summer. The Fisheries Service concluded salmonids’ propensity to occupy
shallow water at the margins of the stream and their immature swimming skills make
them vulnerable to sudden drops in water level, and, as noted, strandings were found
following a period of abrupt fluctuations in stream flow in 2008. The Board’s conclusion
the sudden drops in stream flow were caused by the unregulated diversion of water for
the purpose of frost protection was based on studies finding that the drops were
associated with predicted sub-freezing air temperatures, had been increasing in recent
years, and did not occur in areas without vineyards. It is a logical inference from these
observations that growers’ frost protection diversion was the cause of the sudden drops.
The Board’s conclusions were further supported by a study prepared by the Fisheries
Service, which surveyed a wide range of scientific literature and concluded, “the threat of
frost protection on salmonids is significant and widespread throughout the Russian River
watershed.” (Nat. Marine Fisheries Service, Frost Protection Threat Assessment for
Threatened and Endangered Salmonids in the Russian River Watershed (Draft, Nov. 10,
2009) p. 2.) In fact, one of the April 2008 strandings was traced directly to a single event
of water diversion for frost protection by a particular grower at Felta Creek. Giving due
deference to the Board’s expertise, and recognizing our obligation to resolve conflicts
and draw inferences in the Board’s favor, we conclude the foregoing provides substantial


                                             31
evidence to support the Board’s conclusion that some regulation of growers’ diversion of
water for frost protection was necessary to prevent unwarranted salmonid mortality.
       The Sacramento plaintiffs fault the four scientific studies reproduced in the record,
arguing none of them directly connects salmonid strandings with water diversion for frost
protection. The Lights criticize the work of the Fisheries Service in investigating the
stranding problem and argue the actual mechanism of salmonid stranding is not well
understood. It appears to be unknown, for example, whether stranding occurs because
the “stage,” or height, of the water drops below a certain level, or because the drop in
stage occurs too quickly, or from an interaction of the two factors—for example, a rapid
drop from an already low stage. It appears similarly unknown how such a drop in stage is
correlated with the volume of water flowing in the watercourse, which is the actual
measurement normally made in monitoring stream flow.
       While we acknowledge the validity of some of plaintiffs’ observations about the
shortcomings of the current level of scientific knowledge, they do not lead to the
conclusion the Board’s finding of necessity was not supported by substantial evidence.
As to the Sacramento plaintiffs’ criticisms, the four studies discussed were not the only
scientific evidence in the record. The Fisheries Service study mentioned above
summarized the findings of a number of studies of hydrology and salmon biology,
explaining the mechanism of salmonid stranding and supporting the Board’s reasoning
with respect to the impact of frost protection diversion. The Lights’ observations about
the precise mechanism of stranding highlight the uncertainty about the type of corrective
actions necessary and when they should be employed, but they do not suggest the
Board’s conclusions about the need for some type of regulation are unsupported. Given
the evidence discussed above, the Board’s inference associating salmonid mortality with
the dramatic and sudden declines observed during periods of low temperature is a
reasonable one, as is the inference connecting those declines with diversion for the
purpose of frost protection. Our standard of review requires us to draw all reasonable
inferences in the Board’s favor. (Associated Builders & Contractors, Inc. v. San
Francisco Airports Com., supra, 21 Cal.4th at p. 374.) While it may be uncertain from


                                             32
the record precisely what type of regulation of frost protection diversion is necessary to
protect salmonids, the need for some type of regulation is supported by substantial
evidence.19
       The Lights contend the Board’s evidence was “concocted,” citing an attorney
letter submitted to the Board on behalf of a winery. The letter provides no evidence, or
even argument, to refute the genuine nature of the strandings found by the Fisheries
Service. Instead, it argues (1) voluntary efforts by growers combined with better
coordination of water releases by the SCWA make future similar strandings less likely;
(2) the combination of low flow and frost threat that led to the 2008 incident was
relatively rare, having occurred in only 5 of the last 19 years; (3) and the actual cause of
the strandings was the failure of the SCWA in April 2008 to meet its “instream flow
requirements.”
       None of these arguments demonstrate the finding of necessity for the Board’s
regulation was not supported by substantial evidence. As the trial court recognized, it
was within the Board’s discretion to disregard the effects of voluntary efforts to mitigate
the problem, since these efforts could be reversed or abandoned in the absence of
compulsory regulation.20 In any event, the evidence that voluntary efforts had mitigated

       19
         The Sacramento plaintiffs also argue the regulation is overbroad because it
“declares unreasonable hundreds of frost protection diversions” without sufficient
evidence. In fact, Regulation 862 does not declare unreasonable any particular frost
protection diversion and appears designed to produce WDMP’s that would restrict frost
protection diversion only when a particular combination of hydrology and weather
conditions suggests a threat to salmonids.
       20
          As the draft environmental impact report prepared in connection with
Regulation 862 noted in finding voluntary programs inadequate, “Review of local
voluntary efforts shows that the scope of the frost protection threat is beyond the ability
of local organizations to manage on a strictly voluntary basis. The voluntary programs
submitted for review did not have adequate plans for conservation in tributary streams,
including monitoring programs. Conservation and monitoring in tributaries is important
since these are locations where the impacts of water diversion for frost protection are
likely most acute, and where the majority of the salmonid habitat is located. In addition
the voluntary programs do not possess the authority or willingness to ensure full
compliance with proposed activities.”


                                             33
the problem in the areas immediately surrounding the documented strandings, cited in the
letter, did not support a finding of successful mitigation elsewhere on the stream system.
As to the release of more water by the SCWA, the Board was entitled to rely on the
SCWA’s own conclusion that additional releases of water alone could not cure the
problem, both because of the difficulty of accurately predicting the need for such releases
and because the problem is one of sudden drops caused by uncoordinated diversion,
rather than a more general lack of sufficient water in the system. Finally, as to the rarity
of the causative conditions, this will presumably be taken into account in the WDMP’s.
Given the potential impact on endangered and threatened salmon populations by these
incidents, their rarity would be an argument for regulation responsive to environmental
conditions, as Regulation 862 requires, not for an absence of regulation altogether.
E. CEQA
       The Board prepared an initial draft environmental impact report in May 2011 and
issued a revised draft environmental impact report (EIR) four months later. The trial
court found the EIR inadequate because (1) it failed to assess the impact on strandings of
diversions other than for frost protection purposes, (2) it contained no determination of
the flow levels necessary to protect salmonids, (3) it failed to adopt reasonable mitigation
measures, and (4) it failed to identify and analyze other environmental impacts.
       “ ‘Section 21168.5 [of the Public Resources Code] provides that a court’s inquiry
in an action to set aside an agency’s decision under CEQA “shall extend only to whether
there was a prejudicial abuse of discretion. Abuse of discretion is established if the
agency has not proceeded in a manner required by law or if the determination or decision
is not supported by substantial evidence.” As a result of this standard, “The court does
not pass upon the correctness of the EIR’s environmental conclusions, but only upon its
sufficiency as an informative document.” [Citation.]’ [Citation.] ‘We may not set aside
an agency’s approval of an EIR on the ground that an opposite conclusion would have
been equally or more reasonable.’ [Citation.] [¶] ‘An appellate court’s review of the
administrative record for legal error and substantial evidence in a CEQA case, as in other
mandamus cases, is the same as the trial court’s: The appellate court reviews the


                                             34
agency’s action, not the trial court’s decision; in that sense appellate judicial review
under CEQA is de novo.’ ” (In re Bay-Delta etc., supra, 43 Cal.4th 1143, 1161–1162.)
       1. Failure to Consider Other Diversions
       As discussed above, the flow in the Russian River stream system is determined in
part by water releases from two large dams. In addition, as the EIR noted, water is
diverted from the system for a number of purposes other than frost protection; less than
one-third of the persons and entities having water rights in the system use those rights for
purposes of frost protection. The trial courted faulted the EIR for failing to quantify these
other diversions, including the amount of water impounded by the dams during the
relevant March to May period, concluding it was “essential . . . to comprehend how in-
stream flows levels [sic] are being impacted during the frost season.” The Sacramento
plaintiffs contend, and the trial court found, the EIR was deficient because it failed to
consider the impact on salmonid strandings by these various other diversions.
       The EIR explained its failure to address other sources of diversion in its response
to comments. Replying to a comment that “diversion by the urban contractors and the
[SCWA] must be considered,” the Board explained, “municipal diversions along the
mainstem Russian River are not included in the proposed regulation because these
diversions are made at a rate that is known and accounted for by [SCWA’s] releases to
maintain flows.” (Div. of Water Rights, State Water Resources Control Bd., Responses
to Public Comments on the May 2011 Draft Russian River Frost Protection Regulation
(Sept. 2011) p. 77.) In response to another comment, the Board explained that diversion
for irrigation was not considered because irrigation use was “self randomizing and of
relatively low intensity. Frost protection is essentially the opposite. During major frost
events, almost everyone is forced to protect all of their crops simultaneously using high-
volume overheard sprinkler systems . . . . This acute demand can cause large, short term
fluctuations in flow.” (Id. at p. 83.)
       In essence, the Board declined to quantify and otherwise consider in more detail
other types of diversion because, it believed, they did not affect the problem of salmonid
stranding. As discussed at length above, the Board concluded stranding is caused by


                                             35
sudden drops in stream level associated with simultaneous, large-scale diversion for the
purpose of frost protection. Conversely, the Board reasoned, because the other sources of
diversion occur at a relatively steady and predictable pace that is compensated for by the
dam releases, they have no impact on stranding. Since, as discussed above, the Board’s
view is supported by substantial evidence, we find no abuse of discretion in the failure of
the EIR to consider this issue. Plaintiffs may disagree with the Board about the cause of
the strandings, but the Board was not required to adopt their views in compiling the EIR.
       We also find no abuse of discretion in the EIR’s failure to quantify the amount of
water retained by the dams. Given their importance in regulating flow on the stream
system and the legal constraints governing their release of water, the operation of the
dams is, in effect, part of the environmental baseline. The EIR described their role in its
“Background” section: “[SCWA] operates Lake Mendocino and Lake Sonoma for water
supply purposes in accordance with State Water Board Decision 1610, which set instream
flow requirements for the mainstem Russian River below Lake Mendocino and for Dry
Creek below Lake Sonoma.” Because SCWA is legally constrained in maintaining
instream flow by the terms of the Board decision, the amount of water retained is
irrelevant to a discussion of the environmental impact of Regulation 862.21
       The trial court also faulted the EIR for not considering larger releases from the
dams in anticipation of predicted frost in its alternatives section. As the Board noted in
response to a comment, “due to the location and operational limitations of the dams,
releases from [the dams] simply cannot independently mitigate for the rapid increase in
demand for water for frost protection.” In other words, the alternative suggested by the
trial court would not address the problem targeted by the regulation. “[A] lead agency
may structure its EIR alternative analysis around a reasonable definition of underlying


       21
          To the extent plaintiffs fault the Board for failing to consider increasing the
instream flow as a cure for salmonid stranding, we agree with the Board that plaintiffs are
improperly attempting to dictate the nature of the project. It was within the Board’s
discretion to elect to prevent harm to salmonids by regulating frost protection diversion
rather than opening the sluice gates.


                                             36
purpose and need not study alternatives that cannot achieve that basic goal.” (In re Bay-
Delta etc., supra, 43 Cal.4th at p. 1166.) Because anticipatory releases would not have
solved the problem, the EIR was not required to consider such releases as an alternative.
       2. Minimum Flow Levels
       The trial court concluded the discussion of environmental impacts was inadequate
because the Board had not determined the minimum stream flow necessary to prevent
strandings. Without knowing the minimum level of stream flow that must be maintained,
the court concluded, the Board could not determine the extent to which growers would be
required to alter their frost protection conduct and therefore could not determine the full
environmental impact of the regulation, to the extent environmental impacts were
associated with the various corrective actions.
       The Sacramento plaintiffs make essentially the same argument in contending the
EIR was deficient because it “fails to disclose the conditions necessary to protect
salmonids.” They argue the EIR failed to establish the streamflow conditions sufficient
to protect the salmonids, to correlate the amount of water diverted with streamflow
reduction rates, and to use this information to determine the type and amount of
diversions necessary. Like the trial court, they argue the environmental impacts of the
regulation cannot be understood until these determinations are made.
       Rather than setting a particular flow level, Regulation 862 anticipates that each
WDMP will include a “determination of the stream stage that should be maintained at
each [g]age to prevent stranding mortality.” (Regulation 862, subd. (c)(2)(B).) As all
parties appear to agree, the hydrology of the Russian River stream system and its impact
on salmonid mortality is insufficiently understood to determine what stream level must be
maintained to prevent mortality, or even whether a particular level is necessary. As
discussed above, the assumption underlying the Board’s analysis is that sudden declines
in flow, rather than low flow per se, are responsible for the strandings.
       While the Board was unable to determine with specificity the effect of the
regulation on grower conduct, the EIR did not ignore the issue of the environmental
impact of proposed corrective actions. Section 6.1.2 of the EIR calculated a range of the


                                             37
agricultural acreage that might be required to adopt corrective measures. Subsequent
sections then evaluated the environmental impact of the adoption of such corrective
actions as increased groundwater extraction (Section 6.2), expansion of offstream storage
(Section 6.3), removal of surface water diversion structures (Section 6.4), installation of
wind machines (Section 6.5), installation of heaters (Section 6.6), and installation of
stream stage gauges (Section 6.7), as well as “Other Potential Actions That May Be
Taken by Affected Persons That Are Not Anticipated to Result in Significant Impacts to
the Environment” (Section 6.8). The problem identified by the trial court is not that the
EIR disregarded the environmental impacts associated with corrective actions, but that
the EIR was hampered in estimating the cumulative effect of these individual impacts
because it could not determine to what degree corrective actions would be necessary. In
effect, the trial court held that an adequate EIR could not be prepared until considerably
more study had been done.
       The trial court’s ruling required a legally unnecessary level of precision from the
Board. “ ‘In determining the adequacy of an EIR, the CEQA Guidelines look to whether
the report provides decision makers with sufficient analysis to intelligently consider the
environmental consequences of a project. [Citation.] . . . “. . . The courts have [therefore]
looked not for perfection but for adequacy, completeness, and a good faith effort at full
disclosure.” [Citation.]’ [Citation.] The overriding issue on review is thus ‘whether the
[lead agency] reasonably and in good faith discussed [a project] in detail sufficient [to
enable] the public [to] discern from the [EIR] the “analytic route the . . . agency traveled
from evidence to action.” ’ ” (California Oak Foundation v. Regents of University of
California (2010) 188 Cal.App.4th 227, 262.) As stated in California Code of
Regulations, title 14, section 15204 (CEQA Guideline 15204), “the adequacy of an EIR is
determined in terms of what is reasonably feasible, in light of factors such as the
magnitude of the project at issue, the severity of its likely environmental impacts, and the
geographic scope of the project. CEQA does not require a lead agency to conduct every
test or perform all research, study, and experimentation recommended or demanded by



                                             38
commentors . . . . as long as a good faith effort at full disclosure is made in the EIR.”
(CEQA Guideline 15204, subd. (a).)
       The Board’s discussion of the environmental impacts of the regulation satisfied
the requirement of a good faith effort evaluation, based on reasonably available
information. The Board estimated the number of acres that would be affected by the
regulation and described the environmental impacts associated with the various changes
that might be associated with implementation of the regulation. The objective was
sufficient analysis to permit an intelligent evaluation of environmental consequences. As
CEQA Guideline 15204 notes, an important factor in this equation is the severity of the
identified environmental impacts, since greater environmental impact will require a more
extensive discussion. The environmental impacts of the corrective actions, as disclosed
in the EIR, are limited. Even if it were possible to provide the greater precision
demanded by the trial court, that precision is unlikely to have materially changed the
magnitude of the likely environmental consequences.
       Moreover, it is an open question whether the information sought by the trial court
and the Sacramento plaintiffs, the stream flow conditions necessary to prevent harm to
the salmonids, would lead to a materially more precise estimate of the environmental
impacts, given the wide variety of stream types, acreages, and corrective actions
available. Even if the Board had been able to specify with more accuracy the conditions
under which corrective action is necessary, those conditions vary widely over the entirety
of the stream system. For this reason, it would remain difficult to determine the number
and identity of growers required to adopt corrective actions. Further, even if those
growers could be identified in some manner, it would be impossible to determine which
of the several alternative corrective actions they would adopt, and therefore to estimate
the environmental impacts with greater precision. The trial court and the Sacramento
plaintiffs are seeking a level of precision that is, as a practical matter, unavailable and is
unnecessary for a good faith and reasonable consideration of the environmental impact of
the regulation.



                                              39
       The Sacramento plaintiffs contend the lack of such information will result in a
large number of environmental impact reports from individual WDMP’s, resulting in
potentially conflicting estimates of environmental impact. We decline to speculate about
the necessity for additional environmental impact reports and hold only that, given the
reasonably available information, the Board’s EIR adequately considered the
environmental impact of the regulation.
       3. Reasonable Mitigation Measures
       The trial court’s ruling that the EIR failed adopt adequate mitigation measures was
linked to its ruling that the EIR was deficient for failing to specify a minimum stream
flow. As the court explained, in the absence of that number, “the expected reaction or
adjustments to frost protection practices cannot be reliably predicted. The mitigation
measures necessary to the concomitant environmental impacts resulting from those
adjustments that are predicted in the EIR is unforeseeable and therefore inadequately
specified or addressed in the EIR.”
       The mitigation section of the EIR, Section 7.2, separately considered each of the
corrective actions discussed in the impacts section, such as increased groundwater
extraction, construction of new water storage facilities, and use of alternative frost
protection means, and adopted a series of measures to mitigate the environmental
consequences found for each corrective action. In other words, it required the corrective
actions to be implemented in an environmentally sensitive manner.
       “If it is feasible to do so, a public agency must mitigate or avoid the significant
environmental effects of a project that it carries out or approves.” (South County Citizens
for Smart Growth v. County of Nevada (2013) 221 Cal.App.4th 316, 336.) “ ‘ “ ‘CEQA
does not require analysis of every imaginable alternative or mitigation measure; its
concern is with feasible means of reducing environmental effects.’ ” ’ [Citation.]
‘ “Feasible” means capable of being accomplished in a successful manner within a
reasonable period of time, taking into account economic, environmental, social, and
technological factors.’ [Citation.] Mitigation measures that cannot be legally imposed or



                                             40
enforced need not be proposed or analyzed.” (San Diego Citizenry Group v. County of
San Diego (2013) 219 Cal.App.4th 1, 16.)
       The trial court did not conclude the measures proposed by the Board for the
corrective actions would not result in the mitigation of the significant environmental
impacts caused by implementation of Regulation 862, nor did it conclude there were
additional feasible mitigation measures that were not considered by the Board. Instead,
the court found the discussion of mitigation measures inadequate because the Board
could not predict what mitigation measures would be necessary until the minimum stream
flow was specified. This confused two separate concepts: the corrective actions
necessary to prevent salmonid mortality and the mitigation measures necessary to
minimize the environmental impact from those mitigation measures. While it might not
be possible to specify what particular corrective actions must be adopted until the factors
affecting stranding are better understood, the same is not true of the mitigation measures
necessary to minimize the environmental impact of those corrective actions. Because the
environmental impacts of the corrective actions are understood, the Board was able to
specify and adopt appropriate measures to minimize those impacts. When and if it is
necessary to implement any particular corrective actions, the mitigation measures will
ensure implementation is done in an environmentally sensitive manner. This is all the
Board was required to do to satisfy its obligation under CEQA to adopt feasible
mitigation measures.
       4. Other Environmental Impacts
       The trial court found the EIR’s discussion of environmental impacts inadequate
because it did not include a discussion of the impacts caused by growers abandoning
agriculture due to the costs associated with compliance with Regulation 862. The EIR
discussed this possibility: “Land conversion was not considered a feasible method of
compliance. The proposed regulation does not restrict operations or financially impact
the vineyard or orchard owner at a significant enough level to assume that an owner
would forfeit the agriculture business and explore other land use alternatives. The
proposed regulation . . . . allows for a business to comply with the regulation at the least


                                             41
cost, therefore it is highly unlikely that land conversion would occur.” The trial court
rejected this conclusion as “unsupported,” criticizing the Board’s cost estimates and
citing comments by growers who anticipated a substantial impact on their operations.
       Contrary to the trial court’s finding, the EIR’s conclusion was not unsupported. In
reaching this conclusion, the Board relied on a 46-page study entitled, “Economic
Impacts of the Proposed Russian River Frost Regulation.”22 (Office of Research,
Planning & Performance, State Water Resources Control Bd., Economic Impacts of the
Proposed Russian River Frost Regulation (May 2, 2011).) One section of the study
contained an estimate of the vineyard and pear orchard acreage that would be taken out of
production as a result of the implementation of Regulation 862. The study concluded that
in the two affected counties, 159 of a total of 21,198 acres of vineyard and orchard land,
or less than 1 percent, would be taken out of production. The study constitutes
substantial evidence to support the Board’s conclusion that the environmental impact of
farmland conversion will be insignificant. The trial court was not permitted to disregard
this evidence merely because commenters disagreed with its conclusions. (North Coast
Rivers Alliance v. Marin Municipal Water Dist. Bd. of Directors (2013) 216 Cal.App.4th
614, 626.)
       The Sacramento plaintiffs argue, in addition, the EIR failed to consider the impact
on “non-salmonid ‘special status’ species,” which are other plant and animal species
threatened or potentially threatened. An appendix to the EIR identified some 22 special
status plants and 26 special status animals native to riparian habitats in California.23


       22
         This study was not cited by the Board in its discussion of the issue below and
might not have been readily available to the trial court. In the appellate record, the study
is found on a CD containing administrative record documents supplementing those
submitted in hard copy to the trial court.
       23
          Contrary to the Sacramento plaintiffs’ characterization, this appendix does not
list special status species “that may be impacted” by Regulation 862. While all the listed
species are apparently found in California riparian habitats, the appendix does not even
identify which are actually found in the Russian River stream system, let alone which, if
any, are potentially affected by implementation of the regulation.


                                              42
       Contrary to plaintiffs’ claims, the EIR did discuss the impact of the regulation on
some special status species. Section 4.7 of the EIR, describing the “environmental
setting,” notes in general terms the existence of such species in the Russian River stream
system, without identifying particular plants or animals present. In the discussion of
environmental impacts, the EIR referred several times to the potential for disturbance of
special status species and their habitats. In discussing the removal of existing diversion
structures, the EIR noted it “would reduce the available habitat used by special-status
species such as the western pond turtle and red-legged frog.” While the discussion of
other species is by no means detailed, the EIR notes the potential for adverse impacts on
special status species when appropriate. In the absence of evidence the EIR ignored
specific known risks to such species, the discussion is adequate.
       5. Other CEQA Arguments
       In addition to seconding the conclusions of the trial court, the Lights raise a series
of additional CEQA issues either not considered or rejected by the court.
       The Lights first contend the Board’s adoption of the resolution certifying the EIR
violated Public Resources Code Article X, Section 21082.1, subdivision (c), which
requires a lead agency to “[i]ndependently review and analyze any report or declaration
required by this division,” and California Code of Regulations, title 14, section 15090,
subdivision (a), which requires the agency to certify the EIR “[p]rior to approving a
project.” The claim is based entirely on a Board member’s inadvertent reference, in
moving adoption of the resolution certifying the EIR and adopting the regulation, to the
“regulation” rather than the “resolution.”
       The Board considered adoption of Regulation 862 at a meeting on September 20,
2011. At the commencement of the meeting, the Board chairperson described the
purpose of the meeting as consideration of both the proposed regulation and the
associated EIR. An initial presentation by staff reviewed the process by which
Regulation 862 was developed, including preparation of the EIR. Following extended
public comment, the Board adjourned to allow the staff “to confer about any comments
they heard today, CEQA-related comments they may need to respond to on the record.”


                                             43
When the Board reconvened, the members questioned staff about various aspects of the
proposed regulation, including aspects of the CEQA process and the EIR. At the
conclusion of the meeting, a Board member moved adoption of the “regulation,” rather
than adoption of the resolution that adopted the regulation and certified the EIR. The
motion passed unopposed, and the Board adjourned. Promptly thereafter, while all
members of the Board were still present, the Board’s counsel clarified that the motion
was for adoption of the “resolution.” The chair responded, “Yes, yes,” while at least one
member nodded her head in assent.
       We find no merit in any argument based on the Board member’s slip-of-the-
tongue reference to the “regulation” rather than the “resolution.” Adoption of a
resolution is the procedural vehicle for the adoption of a regulation. The mistaken
reference to adoption of the “regulation,” as opposed to the “resolution,” was
understandable. Because the matter on the agenda was presumably the adoption of the
resolution, there was no ambiguity in the Board’s action, and any uncertainty was cured
by counsel’s clarification. We also find no basis for the claim of a violation of Public
Resources Code section 21082.1, since the record of the meeting plainly reflects the
Board’s conscious consideration of the EIR. The Lights offer a number of legal theories
justifying their presentation of this marginal argument, but they cite no case law holding
that a slip of the tongue constitutes a prejudicial procedural error.
       The Lights also argue that Regulation 862 was inappropriate for treatment as a
program environmental impact report under California Code of Regulations, title 14,
section 15168, since a program environmental impact report is intended to “control a
series of future activities,” whereas Regulation 862 imposed an “immediate and
pervasive” ban on frost protection diversion not undertaken pursuant to a WDMP.
Contrary to the Lights’ claim, the Board made clear its intent not to enforce the ban in
Regulation 862 on unregulated diversion until after a period for investigation and
adoption of WDMP’s, during which project environmental impact reports can be
prepared, if necessary. The regulation itself does not require growers to cease diversion
until a WDMP has been formulated and approved (Cal. Code Regs., tit. 14, § 15168,


                                              44
subd. (c)(4)), and the resolution adopting the regulation states compliance will not be
enforced until at least two years after the regulation becomes effective. We find no abuse
of discretion in the Board’s decision to proceed by way of a program environmental
impact report.24
       Finally, the Lights contend the Board’s findings were inadequate because they did
not explain why alternative methods of frost protection were less harmful to the
environment than direct diversions. In fact, the Board noted the possible impacts of the
alternative methods of frost protection, stated they could be subject to a future project-
level environmental impact report if undertaken on a significant scale, and found that,
taking the effects of these alternative methods into account, “the economic, social, and
environmental benefits of the regulation outweigh any unavoidable adverse
environmental effects.” This was sufficient under Public Resources Code section 21081,
subdivision (b). (See, e.g., The Flanders Foundation v. City of Carmel-by-the-Sea (2012)
202 Cal.App.4th 603, 624.)
                                   III. DISPOSITION
       The orders granting a preliminary injunction and the judgment granting a writ of
mandate are reversed, and the preliminary injunction is dissolved.

                                                  _________________________
                                                  Margulies, Acting P.J.

We concur:
_________________________
Dondero, J.


_________________________
Banke, J.


       24
         We note that our holding is based in part on the Board’s declaration of intent not
to enforce Regulation 862 during the initial stages of its implementation. Any change in
the Board’s position following remand would call into question the validity of our
reasoning.


                                             45
Trial Court: Mendocino County Superior Court

Trial Judge: Hon. Ann Moorman

Counsel:

Kamala D. Harris, Attorney General, Robert W. Byrne, Gavin G. McCabe, Assistant
Attorneys General, Russell G. Hildreth and William Jenkins, Deputy Attorneys General,
for Defendant and Appellant.

Carter, Momsen & Knight, Jared G. Carter and Matisse M. Knight for Plaintiffs and
Respondents Rudolph H. and Linda Light.

Somach Simmons & Dunn, Nicholas A. Jacobs and Richard S. Deitchman for Plaintiffs
and Respondents Russian River Water Users for the Environment, Allan Nelson, Billy
Munselle, Robert Terry Rosetti and Redwood Ranch and Vineyards.

Nancy N. McDonough and Jack L. Rice for California Farm Bureau Federation as
Amicus Curiae on behalf of Plaintiffs and Respondents Rudolph H. Light, Linda Light,
Russian River Water Users for the Environment, Allan Nelson, Billy Munselle, Robert
Terry Rosetti and Redwood Ranch and Vineyards.

Downey Brand, Kevin M. O’Brien and Andrew S. Deeringer for Northern California
Water Association as Amicus Curiae on behalf of Plaintiffs and Respondents Russian
River Water Users for the Environment, Allan Nelson, Billy Munselle, Robert Terry
Rosetti and Redwood Ranch and Vineyards.
