The Canterbury Regional Council, which manages 70 percent of New Zealand's irrigated land, has struggled to control the burgeoning demand for water resources as more land is converted to highly profitable, water intensive dairy farms relying on groundwater. At the center of Canterbury's struggle over water resources and its effective management are two competing groundwater science models. The different approaches and their implications for water management have led to a situation commonly described as a "science impasse" with scientists, policymakers, and stakeholders increasingly focused on "how to break the gridlock over science," particularly in one of the region's major watersheds, the Selwyn. In keeping with the traditional logical positivist, linear approach to science the expectation is that if the scientists can get the science right, then the ultimate goal of water sustainability will be made more likely since the "facts" will guide policymakers toward proper decisions. Yet our research found that while stakeholders do focus tightly on the dominant role of science and scientists when discussing solutions to the impasse, the underlying reality is a societal impasse grounded in the overarching adversarial setting, the logic of the wicked problem set, and the ultimate goal of sustainability. Seeing the "impasse problem" from this new perspective means that getting only the physical science right addresses the symptoms, not the underlying causes of the impasse. The article develops why the traditional instrumental, linear approach to science is unlikely to work in this case and why an alternative approach to science-civic science-offers promise as a way forward. A final section turns to the kind of steps most likely required to transition the Selwyn watershed's "societal impasse" dynamic from an adversarial setting to an effective collaborative governance arrangement conducive to the civic science enterprise. Regional Council-Environment Canterbury (ECan)-which manages 70 percent of NZ's irrigated land using 60% of all water allocated for consumptive use in NZ, is no exception. In the Selwyn watershed of Central Canterbury, ECan has struggled to control the burgeoning demand for water as more dryland farms (mainly sheep) and plantation forests are converted to more profitable water intensive dairy farms relying on irrigation from groundwater. These trends coincide with a period of lower than average rainfall. The result is that lowland streams now experience low or no flows for significant portions of the year.At the center of Canterbury's struggle over water resource management is the science that maps the hydrogeological characteristics of the region. Most dairy farmers, irrigators, and developers prefer a physical processes computer modeling approach--the "Aqualinc" groundwater model. The idea of an impasse runs contrary to the traditional logical positivist, linear approach to science in the policy process that is based on a rational planning model. Implicit to this line of reasoning is the bel...