Groundwater Modeling and Governance: Contesting and Building (Sub)Surface Worlds in Colorado’s Northern San Juan Basin

As groundwater use has surged globally and computing power has grown, groundwater modeling has become a regular feature of subsurface-oriented governance. Our improved ability to “see” underground with models has not, however, generated epistemic consensus on the inner workings of subsurface systems. Here, I ask how and why that is the case. I pursue this line of inquiry in the context of groundwater governance in the American West. Specifically, I trace a decade of groundwater modeling at the heart of a protracted and legally influential groundwater dispute in the state of Colorado to show how models served as mathematical spaces for competing subsurface stakeholders to test and contest opposing visions of groundwater flows, rights, and responsibilities. Drawing from the Science & Technology Studies literature on global climate modeling, I argue that groundwater models are more than simulations of subsurface systems; they are tools of “world building” that embed, enact, and also circumscribe subsurface politics.