Quantifying environmental impacts through the full life cycle assessment of permeable pavements.

Permeable pavements mitigate urban flooding through stormwater infiltration and can also enable rainwater reuse for non-potable purposes. However, their sustainability is often evaluated without a full life cycle perspective that accounts for operational benefits and burdens. This study aims to develop a Life Cycle Assessment (LCA) framework for permeable pavements integrated with rainwater harvesting in buildings and to validate it through a case study. Environmental impacts were assessed using the ReCiPe 2016 method, considering the initial, operational, maintenance and end-of-life phases. The operational phase accounted for nine quantified benefits and burdens. Three permeable pavement scenarios integrated with non-potable rainwater harvesting for a building were compared with a conventional scenario consisting of impermeable asphalt pavement and an exclusive potable water supply. The results indicate that permeable pavements combined with rainwater harvesting show superior environmental performance in most impact categories. Notable reductions were observed in global warming potential, ecotoxicity, toxicity, water consumption and eutrophication, mainly due to urban heat island mitigation, material carbonation, stormwater pollutant removal and partial substitution of potable water. Across the life cycle, the initial and operational phases had the most significant impact. The initial phase contributed between 24% and 84% of total impacts in most categories, except freshwater eutrophication, freshwater and marine ecotoxicity, and water consumption, for which the operational phase dominated, accounting for 71% to 99% of impacts. While results are case-study dependent, the proposed LCA framework is transferable and applicable to other regions worldwide. This research advances knowledge on sustainable urban infrastructure, water resource management and evidence-based urban planning.