(294a) Evaluating Energy-Water Nexus Tradeoffs for U.S Rice Production

Food-energy-water (FEW) systems are connected through numerous links, each one important to assess co-management of resources. This work focuses on irrigation as a critical link to understand interconnections between FEW systems in the United States (U.S.). Food trade presents a pathway for displacing vast quantities of embodied resources and emissions associated with food production. An effectively structured food trade can alleviate local environmental impacts associated with agriculture production. We combine the environmental and resource impacts of irrigation with domestic food trade to assess the tradeoffs that emerge in the context of rice production in the U.S. This work investigates potential for reducing irrigation impacts through reconfiguration of agriculture production and trade with a focus on rice.

Combining data from public agencies we create three distinct networks of rice trade, virtual irrigation water, irrigation embodied energy, and embodied greenhouse gas emissions. We evaluate the feasibility of rewiring the network by keeping the food demand constant and evaluate a series of constraints pertaining to energy-water usage to understand whether production shifts can result in environmentally optimal outcomes for food, energy, and water systems. We observe that rewiring for virtual water results in modest savings of 2%. On the other hand, optimizing for GHG emissions embodied in irrigation results in 17% savings and optimizing to reduce transport emissions result in 25% network level reduction. These savings come at the expense of complete local reduction in states such as Mississippi. Other rice producing states undergo varying degree of reduction and increase in production, partly to offset rice production from California. California’s rice production is highly water intensive in the US, but its unique ability to produce specific types of rice at a large scale makes it invaluable for current rice trade. Our results highlight the challenges in optimizing US rice trade with respect to substantially reducing energy-water impacts and simultaneously meeting current demand.