MIDDLE RIO GRANDE RESERVOIR MODELING

• Master’s Thesis: Water Woes Worsen: Middle Rio Grande Reservoir Modeling Projects Declining Water Availability (Advisor: Dr. Alex Mayer)
• School: Michigan Technological University
• Location: Houghton, MI
• Dates: August 2019 – January 2022

For my Master’s research project, I modeled Elephant Butte Reservoir (located in Southern New Mexico, along the Middle Rio Grande) under an ensemble of future climate projections to investigate water availability under climate change.

The model took into account precipitation on the reservoir surface and runoff from the surrounding area, stream flow into the reservoir, and evaporation from the reservoir surface. Reservoir releases were calculated using a simplified version of the equation used to determine how much water will be allocated to water users each year. Spoiler alert, the majority of projections indicate there will be less water available in the future, but if you’re interested in the whole journal article you can find it here (no paywall!).

To me, the most interesting part of hydrology is working to understand processes and complex systems interactions. In this case, hotter temperatures cause higher evaporation rates; however, in most future climate scenarios, the volume of evaporation didn’t increase because less water flowing into the reservoir forced low reservoir storage which reduced reservoir surface area, limiting evaporation. Which sounds nice for a second until you realize that low storage limits the ability of a reservoir to buffer a drought. Or that less water flowing into the reservoir generally limits management options.

The bottom line is, like most of the American West, the Middle Rio Grande will not have enough water to continue business-as-usual as we move into the future. Or, as Dettinger (2015) put it, “Nineteenth-century water law, twentieth-century infrastructure, and twenty-first-century population growth and climate change are on a collision course throughout the West.”