Integrating local and expert knowledge for enhanced hydrogeological modelling: a comprehensive exploration through real-world case studies

Reliable predictions of groundwater systems are crucial for sustainable water management, supporting human needs and healthy ecosystems. Groundwater models offer the potential to understand and forecast groundwater flow systems under anthropogenic and climatic influences, providing information for decision-making and hazard risk analysis. Despite significant progress in hydrogeological modelling approaches and uncertainty analysis, modellers still face difficulties in demonstrating the reliability and usefulness of models in decision-making to relevant stakeholders and authorities. One reason for these persistent challenges in conveying what a model can and cannot do may be the fact that traditional hydrogeological modelling often overlooks a valuable resource: local people and expert knowledge. Researchers emphasize that this data, especially in data-scarce areas, offers crucial subsurface insights beyond quantitative data alone. Ignoring it risks wrong conceptualizations and inaccurate predictions. However, the exact methods and the additional hydrogeological information that local people and experts can provide to improve model conceptualization and, consequently, enhance the reliability and accuracy of the model, are yet to be determined. This study explores how integrating local and expert knowledge can bridge this gap, enhancing our understanding and contributing to better conceptualizing and modelling the subsurface. Real-world groundwater modelling examples show that incorporating this knowledge improves our understanding and conceptualization of complex hydrogeology. Integrating local knowledge and expert insights in groundwater modelling not only improves model conceptualization and the reliability of model predictions but also empowers communities by building trust and confidence in model results for sustainable water management solutions.