Connecting inequalities in land ownership and groundwater access: the case of California’s Central Valley
Open Access
- 15 August 2025
- journal article
- Published by IOP Publishing in Environmental Research Letters
- Vol. 20 (9) , 094026
Abstract
Understanding inequality in groundwater access and cropland ownership is critical for assessing the sustainability and equity of agricultural systems, especially in regions facing climatic and socioeconomic patterns such as drought and cropland consolidation. These two forms of access are deeply interconnected: for instance, cropland ownership often determines who can access and control groundwater. Due to data challenges, however, few studies have quantified groundwater access inequality in the same ways that land ownership has been quantified. Similarly, the regional scale of most analyses to date limits our understanding of factors that shape and modify these interconnections. Our study aims to address this gap by constructing a novel geospatial dataset by matching groundwater wells with cropland parcels across California’s Central Valley. We quantify the magnitude and spatial patterns of groundwater and cropland inequality and examine how it scales with land ownership, crop types, and surface water access. Our results indicate substantial inequality in both groundwater access and land ownership, with the top decile of well owners possessing 46.4% of the region’s total well capacity. These well owners are more likely to allocate groundwater to high-revenue, water-intensive perennials such as almonds and walnuts. Furthermore, large landholders tend to have far more wells, deeper and higher-capacity wells, and greater access to surface water resources. However, we observe consistently wider inequality in land ownership than water access, and larger landowners possess less well depth and capacity per hectare. We discuss the implications of these findings in the context of California’s historical lack of regulation on groundwater, particularly with respect to inequality in open access vs private property resources. We also consider possible lessons for future groundwater regulation and distribution mechanisms for groundwater rights under California’s Sustainable Groundwater Management Act.Keywords
Funding Information
- ESPM Summer Research Funding Grant
- USDA Hatch Multistate (Project #W5190 Capacity Fund)
- National Science Foundation (CBET-2144169)
This publication has 49 references indexed in Scilit:
- What water will the UN Conference carry forward: a fundamental human right or a commodity?The Lancet, 2023
- Farm consolidation and turnover dynamics linked to increased crop diversity and higher agricultural input useAgricultural Systems, 2023
- In vino veritas, in aqua lucrum: Farmland investment, environmental uncertainty, and groundwater access in California’s Cuyama ValleyAgriculture and Human Values, 2020
- Land dispossessions and water appropriations: Political ecology of land and water grabs in GhanaLand Use Policy, 2019
- Open access and the sovereign commons: A political ecology of pastoral land tenureLand Use Policy, 2018
- Drought impacts to water footprints and virtual water transfers of the Central Valley of CaliforniaWater Resources Research, 2017
- Intensive groundwater use and (in)equity: Processes and governance challengesEnvironmental Science & Policy, 2015
- Matching and record linkageWIREs Computational Statistics, 2014
- Impact of land fragmentation, farm size, land ownership and crop diversity on profit and efficiency of irrigated farms in IndiaLand Use Policy, 2013
- Aspects of water markets for developing countries: experiences from Australia, Chile, and the USEnvironment and Development Economics, 2002