National Audubon Society v. Superior Court, , is a California Supreme Court decision holding that the public trust doctrine limits appropriative water rights and requires the state to consider and protect public trust uses when allocating water. The public trust doctrine (lowercase per MOS:CAPS) holds that certain resources—traditionally navigable waters and their beds—are held by the state in trust for public uses such as navigation, commerce, fishing, and, under California law, ecological and recreational values. The court concluded that previously granted appropriative rights are subject to continuing state supervision and adjustment to avoid or minimize harm to public trust interests where feasible.

The plaintiffs alleged that the public trust doctrine was being violated due to environmental damages to Mono Lake in the form of significant water level declines as a result of water diversions by the City of Los Angeles Department of Water and Power (DWP). DWP based their defense on the fact that they held permits, issued by the state for the diversions, and so the diversions were allowable.

The central issue in the case was whether appropriative water rights (granted in the past) must consider the public trust doctrine, requiring protection of natural resources by the state. More specifically, the issue being addressed by the court was whether Mono Lake was subject to a public trust, which would invalidate Los Angeles' use of the streams feeding the lake.

The California Supreme Court held that the state, under the public trust doctrine, had continuing responsibility for the state's navigable waters and that the public trust doctrine, therefore, prevented any party from appropriating water in a manner that harmed the public trust interests. However, the court also recognized that LA depended on these diversions as a critical water source, and this in turn mitigated the rule of law as the court held that water transfers were permissible even though some damage to the environment would occur as long as this was kept to minimal harm to the extent feasible. The court described the public trust and the appropriative system as “part of an integrated system of water law” and required decisionmakers to revisit and, if necessary, modify allocations that impair trust uses.

Case summary

In 1979, the National Audubon Society, Mono Lake Committee, and others sued the City of Los Angeles Department of Water and Power (DWP), alleging that diversions from four Mono Lake tributaries lowered lake levels and harmed public trust resources. The public trust doctrine is the cornerstone of this court case. The doctrine originates from Roman law and has persisted throughout European and English Common law. The Institutes of Justinian from the Sixth Century A.D. stated: by the law of nature these things are common to mankind -the air, running water, the sea and consequently the shores of the sea. Some scholars trace California public trust principles to Spanish/Mexican legal traditions; however, the California doctrine principally derives from U.S. common law authorities.

Plaintiffs argued that the public trust doctrine required the state to consider and protect Mono Lake’s recreational and ecological values when allocating water. The public trust doctrine holds that water, fish, and wildlife are shared resources to be held in an exalted position, above that of any industrial, commercial, or private uses in any administrative or judicial review of water allocation, and establishes that the government must uphold and protect this trusteeship as a moral obligation.

Audubon's original complaint, filed with the Superior Court of Mono County, asserted the diversions were a violation of the public trust doctrine, were both a public and private nuisance, and a violation of California State Constitution Article X, Section 4 & Article XVI, Section 6, which respectively prohibit obstruction of navigable waters and gifts by the state of a state asset. The suit attempted to establish Public Trust rights in Mono Basin, and sought declaratory and injunctive relief. The Supreme Court of California held that the state has a continuing duty to supervise and, where feasible, prevent harm to public trust resources, and that appropriative rights are subject to that duty.

Background The basis for the public trust doctrine goes back to Roman law. Under Roman law, the air, the rivers, the sea and the seashore were incapable of private ownership; they were dedicated to the use of the public. In essence, the public trust doctrine establishes the role of the state as having trustee environmental duties owed to the public that are subsequently enforceable by the public. There is judicial recognition of this, dictating that certain rights of the public are key to individual common law rights (such as state recognition of the public right or trust for waterways and coastal zones). Judicial recognition of the public trust doctrine has been established for tidelands and non-navigable waterways,Phillips Petroleum Co. v. Mississippi, 484 U.S. 469 (1988) submerged land (such as lake beds) and the waters above them,New York v. DeLyser, 759 F. Supp. 982 (W.D.N.Y. 1991)Ill. Cent. R. R., 146 U.S. 387 (1892) and preservation of a public interest (such as recreation, swimming, access, and sport fishing).Marks v. Whitney, 98 Cal. Rptr. 790, 491 P.2d 374 (1971)

The leading case that established the public trust doctrine in the U.S. is the 1892 Supreme Court case Illinois Central Railroad v. Illinois. The Court held that public trust submerged lands belong to the respective States within which they are found, with the consequent right to use or dispose of any portion thereof, when that can be done without substantial impairment of the interest of the public in the waters…. setting a precedent for strict scrutiny of any private taking of public trust land. The Court in Illinois voided the deed because under public trust law it did not promote a primary public purpose. This meaning has been supported by Federal and California Court decisions in Woodruff v. North Bloomfield, People v. Gold Run Ditch Mining Co., People ex rel Ricks Water Co. v. Elk River Mill and Lumber Co and People v. Truckee Lumber Co. These cases make it clear as a matter of law one must exercise rights or use property so as not to infringe on the rights, interests or properties of others.

Procedural history

1928: California State Constitution Article X, Section 2 states that all waters of the state must be put to reasonable and beneficial use. Any waters in excess of the "reasonable and beneficial uses" are considered surplus waters available for use by others, as stipulated under the appropriative water rights administered by California State Water Resources Control Board (SWRCB) Water rights are granted by the SWRBC after an application to appropriate water is approved and a permit is issued. The permit allows construction of a project needed to divert the water according to the terms and conditions of the permit, which includes submission of periodic progress reports by the applicant with SWRCB to ensure the application of the water is for beneficial use. If the conditional terms of the permit are met, SWRCB may issue a license to confirm the appropriative rights to the water.

1940: the City of Los Angeles Department of Water and Power (DWP) was granted permits allowing appropriation for the entire flows of four out of five of Mono Lake's tributaries (Lee Vining, Walker, Parker, and Rush Creeks) for municipal use and hydropower generation. Mono Lake's tributaries contain glacial fed snowmelt from the Sierra Nevada and thus convey potable water, whereas the water in Mono Lake itself was and is not potable due to its salinity. Despite being granted permits, DWP lacked the appropriate conveyance facilities to physically appropriate and transport the volume of water that was granted at the time.

1963: The City of Los Angeles authorized the construction of a new aqueduct, the Second Los Angeles Aqueduct to transport surface water from Mono Basin and both surface and groundwater from Owens Basin.

1974: SWRCB issued licenses confirming DWP's right to divert water from Mono Lake tributaries, resulting in annual diversions of approximately of water from Mono Basin since the aqueduct was completed in 1970. The diversions from the second aqueduct caused the surface area of the lake to decrease by one-third and the lake level to drop , exposing of lakebed.

1977: Stanford biologist David Gaines published a study on Mono Lake's ecosystem highlighting the dangers of water diversion that garnered national attention to the potentially catastrophic ecological impacts to Mono Lake from the DWP diversions. This led to the formation of the Mono Lake Committee and a grassroots movement spanning over 30 years to stop the diversions and restore the basin California Water Wars.

1979: The California Department of Water Resources (CDWR) and the United States Department of the Interior (USDI) undertook a joint study of Mono Basin. The study concluded that the level of Mono Lake should be stabilized at . To achieve this goal, drastic reductions of water exports from Mono Basin were recommended from the present annual average of to a limit of . Legislation was introduced to implement this recommendation, but was never enacted.

1979: The National Audubon Society (Audubon), Mono Lake Committee, Friends of the Earth, the Los Angeles Audubon Society, and Mono Basin landowners initiated the original lawsuit with the Superior Court of Mono County in 1979 against Los Angeles Department of Water and Power (DWP), asserting that the diversions were a violation of the public trust doctrine, were both a public and private nuisance, and a violation of California State Constitution Article X, Section 4 & Article XVI, Section 6, which respectively prohibit obstruction of navigable waters and gifts by the state of a state asset. The suit attempted to establish Public Trust rights in Mono Basin, and sought declaratory and injunctive relief.

The Public Trust Case was originally argued as: National Audubon Society v. Los Angeles. Superior Court of Alpine County No. 6429.

The case was transferred to Alpine Superior Court; DWP filed a cross-complaint seeking adjudication of Basin water rights to all appropriators, naming 117 cross-defendants, including the plaintiffs, the State, United States Forest Service, U.S Bureau of Land Management, and other private water users.

DWP also sought a Congressional declaration stating they consented to the impairment of navigable waters of Mono Lake. Finally, DWP asserted that any nuisance at Mono Lake was attributable to the newly exposed lakebed and sought a declaration that conditions resulted from a valid exercise of the police power by the State of California. Simultaneously, Audubon sought permission to include a cause of action based on the federal common law of nuisance, asserting that Mono Lake is an "interstate or navigable" water in which there is an overriding federal interest, and DWP's diversions were causing water and air pollution.