Golden Gate University Environmental Law Journal


California follows a “Golden Rule” of water management, which requires management of the state’s water for maximum beneficial use. This principle is codified at Article X, Section 2 of California’s Constitution. However, the Golden Rule has a qualifier—an asterisk—which requires that water management “preserve water right priorities to the extent those priorities do not lead to unreasonable use.” We call this qualifier the Mojave Rule, named after the California Supreme Court’s decision in City of Barstow v. Mojave Water Agency. The Golden Rule* is the foundation of water management in California and the Mojave Rule is the key qualifier.

This article explores the Golden Rule* as a lens to analyze perplexing water management issues and controversies, including the tension between “public” and “private” interests affected by water management; balancing the countervailing interests of adaptable water management on the one hand, and water supply reliability and legal certainty on the other; the demarcation between reasonable water regulations and a taking of a water right; and the dual roles of the courts to both adjudicate the rights of the litigants and advance implicated social welfare interests affected by water management.

These issues are analyzed here in two parts. Part II explains the overarching constitutional obligation on public agencies and the courts to manage water resources for maximum beneficial use in a manner that reasonably preserves common law water rights. This part discusses the underlying nature of a water right and water right priorities in California and how the Golden Rule* balances the tensions that underlie water management. Part III discusses application of the Golden Rule*. This part explains how the rule may be used to assess whether a water management regulation will sustain legal challenge, the courts’ duty to apply the Golden Rule* in water management conflicts, operation of the Golden Rule* in the recently enacted Sustainable Groundwater Management Act (SGMA), projections concerning the Golden Rule* in future groundwater basin adjudications, and how the rule may apply to conflicts concerning the use of subterranean storage space for groundwater storage and conjunctive use programs. A postscript provides an update on recent California legislation enacted to streamline the judicial procedures applicable to groundwater adjudications and to ensure that future groundwater adjudications are managed consistent with SGMA.