Future scenarios for sustainable water management in Mediterranean agricultural systems: a life cycle case study on water reuse in Northern Italy

Water reuse is a promising strategy to mitigate water scarcity in Mediterranean agriculture yet its uptake remains limited due to low public acceptance, high treatment costs and strict safety regulations. While innovative technologies are emerging, systematic long-term evaluation of their environmental and economic implications are still scarce. This study assesses the sustainability of water reuse scenarios for irrigation in tomato production through a case study in Italy, using Life Cycle Assessment (LCA) and Life Cycle Costing (LCC) to compare reuse-based and conventional irrigation systems. Quantitative analysis was combined with a qualitative foresight involving experts from seven Mediterranean countries to translate the findings into future scenarios and actionable strategies. Results indicate that water reuse scenarios consume 0.03 m3 of water per kg of tomatoes, compared with nearly 1 m3 per kg in conventional systems. From a planetary boundaries perspective, both approaches still exceed safe environmental thresholds in several impact categories. Economically, water reuse slightly raises tomato production costs (0.15 €/kg vs 0.14 €/kg), but current scenario entails higher human health and ecosystem costs (0.06 €/kg vs 0.04 €/kg). The foresight exercise co-designed four qualitative future scenarios for water reuse, emphasising the importance of financial incentives and targeted communication to foster broader adoption. Overall, integrated sustainability assessment combined with experts-based analysis can support evidence-based decision-making and support policy measure to advance sustainable water reuse in Mediterranean agriculture.