Abstract Groundwater from the Ogallala-High Plains Aquifer supports one of the most productive agriculture regions in the world. Yet, despite nearly 40 years of policies designed to conserve and sustain this vital resource, the Aquifer continues to be depleted at an unsustainable rate. We integrate propositions from treadmill of production theory and ecological modernization theory to develop a structural model, focusing especially on the role of technological modernization as a key mechanism motivating depletion. A time-sequenced path analysis of all counties in the Ogallala Aquifer region reveals that groundwater depletion has a strong internal momentum characteristic of an agricultural production treadmill. Technological modernization promotes depletion through Jevon’s Paradox. Increases in water efficiency—more crop per drop—are associated with less groundwater consumption, but more extensive deployments of irrigation infrastructures overwhelm the beneficial effects of increased water efficiency. An income-subsidy mechanism supports the treadmill dynamic. Agricultural production and increased water efficiency do not influence incomes. Instead, incomes are influenced mainly by expansions of irrigation technologies, which generates subsidies, and this dynamic puts further “spin” on the treadmill. The implications of the findings for theory and policy are discussed.