In recent years, western energy and water demands have risen precipitously, straining both energy and water supplies. As population growth continues and climate change reduces available water supplies, the challenge of meeting energy and water demands and protecting valuable natural resources will intensify. Western utilities and government agencies are developing energy and transmission plans that will influence the region for the next several decades and beyond. If these strategies do not consider the availability of water, new electric facilities could have vast impacts on water resources and sectors like agriculture, which uses the majority of water in the West today. Watersheds throughout the West face these challenges, but they are particularly clear in the South Platte River basin in Colorado. Working in close collaboration with the National Renewable Energy Laboratory, the University of Colorado, Colorado State University, and the National Oceanic and Atmospheric Administration, Western Resource Advocates evaluated the impacts of climate change, energy and transmission scenarios, and municipal growth on water resources in the South Platte River basin, as well as the resulting economic impacts on the agricultural sector. The energy scenarios demonstrate three divergent paths in the South Platte: a water-efficient, high-wind future; a carbon- and water-intensive "business as usual" future; and a technology-focused future that reduces carbon emissions but increases water use. The scenarios and results serve as a timely and valuable template for integrating water into regional energy and transmission planning, and will likely be replicable throughout the region.