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Abstract Civil infrastructure underpins urban receipts of food, energy, and water (FEW) produced in distant watersheds. In this study, we map flows of FEW goods from watersheds of the contiguous United States to major population centers and highlight the critical infrastructure that supports FEW flows. To do this, we draw upon detailed records of agriculture, electricity, and public water supply production and couple them with commodity flow and infrastructure information. We also compare the flows of virtual water embedded in food and energy commodity flows with physical water flows in inter‐basin water transfer projects around the country. We found that the virtual blue water transfers through crops and electricity to major US cities was 53 billion and 8 billion m3in 2017, respectively, while physical interbasin water transfers for crops, electricity, and public supply water averaged 20.8 billion m3. Highways are the primary infrastructure used to import virtual water associated with food and fuel into cities, although waterways and railways are most utilized for long‐distance transport. All of the 204 watersheds in the contiguous US support the food, energy, and/or water supplies of major US cities, with dependencies stretching far beyond each city's borders. Still, most cities source the majority of their FEW and embedded water resources from nearby watersheds. Infrastructure such as water supply dams and inland ports serve as important buffers for both local and supply‐chain sourced water stress. These findings can inform efforts to reduce water resources and infrastructure risks in domestic supply chains.
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Drought Impacts to Water Footprints and Virtual Water Transfers of Counties of the United States
Abstract Irrigation is increasingly important to agricultural production and supply chains in the United States. In this study, we seek to understand how irrigation (blue) water footprints of production are spatially distributed and how they differ in drought versus non‐drought years. Similarly, we aim to understand the impact of drought on the irrigation virtually embedded in domestic supply chains and exports. To this end, we quantify the blue water footprints of agricultural products per unit mass produced (Virtual Water Content (VWC)) by surface, groundwater, and groundwater depletion sources, and then trace how this water is embedded in domestic agricultural commodity transfers and exports (Virtual Water Transfers (VWT)) for counties in a drought (2012) and non‐drought (2017) year. Overall, we find that total VWC values are larger in drought than non‐drought conditions across commodity groups, driven by surface water withdrawals. Conversely, VWT is larger in non‐drought than drought, driven by larger commodity mass fluxes during non‐drought. Our results highlight the importance of sustainably managing water resources so that they are available to mitigate the impact of future droughts on agricultural production and supply chains.
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- PAR ID:
- 10609989
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Water Resources Research
- Volume:
- 61
- Issue:
- 6
- ISSN:
- 0043-1397
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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