An improved understanding of the food-energy-water nexus at the asset level (e.g., power plant, irrigation ditch, water utility) is necessary for the efficient management and operations of connected infrastructure systems. Interdependencies potentially influencing the operations of a particular asset can be numerous. For example, operations of energy and agricultural assets depend on the delivery of water, which in turn depend on the physical hydrology, river/reservoir operations, water rights, the networked water infrastructure and other factors. A critical challenge becomes identification of those linkages central to the analysis of the system. Toward this need, a case study was conducted centered on the San Juan River basin, a major tributary to the Colorado River. A unique opportunity was afforded by the availability of two sets of coupled models built on the same simulation platform but formulated at distinctly different fidelities. Comparative analysis was driven by statistically downscaled climate data from three global climate models (emission scenario RCP 8.5) and planned growth in regional water demand. Precipitation was partitioned between evaporation, runoff and recharge using the Variable Infiltration Capacity (VIC) hydrologic model. Priority administration of small-scale water use of upland tributary flows was simulated using Colorado’s StateMod model. Mainstem operations of the San Juan River, including releases from Navajo Reservoir, were subsequently modeled using RiverWare to estimate impacts on water deliveries, environmental flows and interbasin transfers out to the year 2100. Models differ in the spatial resolution, disaggregation of water use, infrastructure operations and representation of system dynamics. Comparisons drawn between this suite of coupled models provides insight into the value of model fidelity relative to assessing asset vulnerability to a range of uncertain growth and climate futures.

Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA-0003525.