A third of Earth’s largest groundwater basins are being depleted by irrigated agriculture, yet little is still known about whether and when resource users will comply with groundwater conservation policies. Although enforcement—monitoring compliance and punishing infractions—is an essential part of any successful management programme, it is a costly endeavour that erodes trust between water agencies and users. Directly studying normative drivers of compliance (e.g., social norms and cultural values) is problematic because rule breakers are usually unwilling to reveal themselves or to discuss their motivations freely, thus bearing data on illegal activity prone to unquantifiable biases. To overcome these issues, we devised the ‘Groundwater Commons Game’ (GCG), an agent-based model of irrigated agriculture rooted in principles of human cooperation and collective action, grounded on the largest dataset of cultural values in existence: The World Values Survey. Simulations of three major aquifer systems currently facing unsustainable demands—the Punjab (India/Pakistan), the Central Valley (USA), and the Murray-Darling Basin (Australia)—reveal ‘tipping points’ where collective attitudes towards groundwater conservation shift abruptly with small changes in cultural values and enforcement provisions. Our results suggest that these tipping points play a significant role in groundwater management, as they define the transition between groundwater overuse and conservation states, and because they can trigger unwanted responses across system domains. Based on these findings, we propose a three-stage approach to achieve long-term regulatory compliance: first, diagnose if the system is close to its tipping points; second, weave non-enforcement factors (social capital) to bring the system to the tipping points; and third, ensure compliance past the tipping points to build systemic resilience. Overall, our work presents new powerful modelling tools for groundwater management that can be used to evaluate how regulatory compliance is contingent upon socioeconomic, institutional, and physical constraints and conditions.