Poster #116 - Seniority and Scarcity: Water Rights, Agricultural Responses, and Spatial Allocation in the Western United States

• In Event: Friday Poster Reception

Abstract

The Western United States is characterized by scarce water supplies, persistent drought, and a heavy reliance on irrigation for agricultural production. The region contributes substantially to national crop output, making water management a critical policy concern. However, water governance is shaped by a complex patchwork of institutions, particularly property rights systems such as prior appropriation, which generates heterogeneous allocation outcomes across states. Under the prior appropriation doctrine, water rights are allocated based on seniority (rights allocated based on who was historically first to use the water). This system creates a rigid hierarchy and unequal risk sharing during droughts where senior water rights holders receive water first and junior holders receive what remains, if any. Prior appropriation rights vary in seniority across space, which in combination with water scarcity, can be a determining factor in where crops are grown, how much land is irrigated, and influence other producer decisions. This paper constructs a novel, high spatial resolution dataset linking water rights, water supply, land use, and economic indicators across multiple western states. To address inconsistencies in state-specific administrative records, an AI-assisted information retrieval and classification approach is used to identify water rights definitions. The dataset captures substantial cross-state heterogeneity in agro-ecological conditions, water access, cropping patterns, and institutional structures.

This study is interested in understanding how water rights under the prior appropriation doctrine have shaped the geographical distribution of agricultural production and whether agricultural producers exhibit differential responses to water scarcity depending on the seniority of their water rights. Preliminary evidence reveals extreme skewness in the distribution of surface water allocations, with a small fraction of rights accounting for a disproportionate share of total allocated volume. There is also evidence of concentration and spatial clustering of high-volume surface water rights, particularly in regions such as Colorado and Utah within the Upper Colorado River Basin. This preliminary evidence provides a foundation to explore how heterogeneity in water rights interacts with crop choice and irrigation decisions, with implications for the spatial allocation of agricultural production. Using a partial equilibrium model, the study examines the potential for broader spillover impacts of these local institutional distortions. Beyond identifying the spillover impacts, the findings aim to highlight differences in agricultural outcomes driven by water rights structures and underscore the importance of incorporating governance and institutional indicators into economic modeling for policy.

Author

• Kavitha Srikanth, Purdue University
  Presenting Author