Colorado River Water in Southern California: Evolution of the Allocation Framework, 1922-2015

Abstract

An elaborate and nested legal framework, with both interstate and intrastate components, governs allocation of Colorado River water to and within Southern California. This framework has evolved for nearly a century, and this paper chronicles major milestones within this evolution. The narrative is framed with the formation of the Colorado River Compact in 1922 as a front bookend, and recent developments involving the Quantification Settlement Agreement, Salton Sea restoration, and the Interim Shortage Guidelines as back bookends. Reflections on the iterative and provisional nature of the evolutionary process, and Southern California's relative degree of water security resulting from it, appear in the conclusion.

Keywords: water law, water policy, water allocation, colorado river, interstate compacts, Colorado River Compact, supreme court decrees, Arizona v. California, quantification settlement agreement, interim guidelines