Environmental modeling is a powerful tool for facilitating discussions among stakeholders involved in decision-making for environmental planning. This article explores how models can be used to structure stakeholder discussions by visualizing the opportunity space – the range of interventions that are deemed to be technically and physically feasible – and how it overlaps (or does not) with the decision space – the set of interventions considered acceptable or desirable by stakeholders. Using the case study of the Aa of Weerijs catchment in the Netherlands and Belgium, we demonstrate how different model contributions (sensitivity analysis, impact assessment and scenario evaluations at catchment and local levels) can aid these discussions by providing structured insights into potential interventions, both within the opportunity and decision spaces. The findings highlight how models can bridge gaps between stakeholders and technical experts by facilitating more effective discussions and better-informed decision-making processes in environmental planning.
