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Growing societal water demands and decreasing water supplies are straining the water available for communities in many basins. Once water supplies have been fully allocated and developing new water supplies is infeasible, the best option to meet growing water demands is often to reallocate water from rural agricultural water uses. Yet, the dynamics and implications of these rural‐to‐urban water transfers are poorly understood. Here, we integrate an agent‐based model with an input‐output model to capture the behavior of individual irrigators and examine how their water transfer decisions propagate through the broader rural economy and shape social dynamics. As a demonstration of our model, the rural community represents Alamosa County while the city represents the city of Denver, both located in Colorado, Unites States. We find that the greatest long‐term decline in crop water use corresponds with higher city growth rates while the greatest short‐term decline corresponds with larger farmer discount rates. As farmers sell their water rights to the City, economic activity from the crop production sector declines, causing unemployment in the crop production sector to increase and demand from the service sectors to decrease, which results in output declining in these economic sectors as well. Thus, a negative impact on the agricultural sector will cause some negative impact on other economic sectors, such as professional, health care, and recreational services. This research brings new insights that can be used to evaluate the socio‐economic impacts of water transfers and shape policy to minimize potential negative externalities associated with water transfers. 

Abstract This study investigates residential indoor water consumption variability across 39 US cities using data from 26,441 single‐family smart water meters. Employing functional data analysis and mixed‐effects random forest, we identified distinct usage patterns across city clusters, with 13 high and 6 low water‐using cities (all in coastal California) differing significantly from 20 medium water‐using cities. Shower and toilet use were primary drivers of indoor use differences between clusters, influenced by both behavioral and fixture efficiency factors. The presence of appliances, certain household features, and weather also affect indoor water use, with varying influence on indoor water use across clusters. Our findings highlight the effectiveness of state‐level water efficiency interventions and emphasize the importance of considering both behavioral factors and appliance efficiency in conservation strategies, providing valuable insights for targeted water demand management in urban areas. 

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. 

Irrigation reduces crop vulnerability to drought and heat stress and thus is a promising climate change adaptation strategy. However, irrigation also produces greenhouse gas emissions through pump energy use. To assess potential conflicts between adaptive irrigation expansion and agricultural emissions mitigation efforts, we calculated county-level emissions from irrigation energy use in the US using fuel expenditures, prices, and emissions factors. Irrigation pump energy use produced 12.6 million metric tonnes CO2-e in the US in 2018 (90% CI: 10.4, 15.0), predominantly attributable to groundwater pumping. Groundwater reliance, irrigated area extent, water demand, fuel choice, and electrical grid emissions intensity drove spatial heterogeneity in emissions. Due to heavy reliance on electrical pumps, projected reductions in electrical grid emissions intensity are estimated to reduce pumping emissions by 46% by 2050, with further reductions possible through pump electrification. Quantification of irrigation-related emissions will enable targeted emissions reduction efforts and climate-smart irrigation expansion. 

Innovative groundwater management strategies are needed to preserve aquifers for crop irrigation. For sustainability to be lasting, any strategy must balance environmental goals with the economic aims of farmers. These tradeoffs are difficult to manage due to the inherent uncertainty in farming. To address these challenges, we develop a transferable two‐stage stochastic modeling framework to support optimal multi‐year crop and irrigation planning under groundwater pumping restrictions and uncertain precipitation. This modular framework is broadly applicable to regions facing groundwater overuse, helping to balance aquifer sustainability and farmer profitability under uncertainty. We illustrate the model using a case study from western Kansas, USA, where irrigators self‐imposed 5‐year groundwater pumping limits to extend the aquifer's lifespan. While these multi‐year allocation periods offer flexibility, they introduce a temporal dimension to decision‐making beyond typical annual planning. Optimal cropping and irrigation strategies from the stochastic model significantly outperform observed farmer behavior during the first two 5‐year allocation periods (2013–2022), and outperform a deterministic model assuming long‐term average precipitation during dry conditions. We show that optimal crop choices shift from corn to sorghum under more stringent pumping restrictions. Under these constraints, irrigators benefit by conserving water in earlier years and using more in later years, whereas the reverse holds under more lenient restrictions. Extending the allocation window further enhances profitability, though marginal gains diminish beyond 7 years. This modeling framework offers insights for agricultural regions seeking to improve long‐term groundwater management through strategies that support both economic resilience and hydrologic sustainability. 

Virtual water describes water embedded in the production of goods and offers meaningful insights about the complex interplay between water, trade, and sustainability. In this Review, we examine the trends, major players, traded products, and key drivers of virtual water trade (VWT). Roughly 20% of water used in global food production is traded virtually rather than domestically consumed. As such, agriculture dominates VWT, with livestock products, wheat, maize, soybean, oil palm, coffee, and cocoa contributing over 70% of total VWT. These products are also driving VWT growth, the volume of which has increased 2.9 times from 1986 to 2022. However, the countries leading VWT contributions (with China, the United States, the Netherlands, Germany, and India, accounting for 34% of the global VWT in 2022) have remained relatively stable over time, albeit with China becoming an increasingly important importer. VWT can mitigate the effects of water scarcity and food insecurity, although there are concerns about the disconnect between consumers and the environmental impacts of their choices, and unsustainable resource exploitation. Indeed, approximately 16% of unsustainable water use and 11% of global groundwater depletion are virtually traded. Future VWT analyses must consider factors such as water renewability, water quality, climate change impacts, and socio-economic implications.