Life Cycle Assessment of Road Expansion: Implications for Sustainable Infrastructure Development in Developing Countries ^†

In developing countries like El Salvador, road infrastructure expansion projects are often subject to environmental impact assessments (EIAs), yet these typically exclude supply chain impacts. This study applied a life cycle assessment (LCA) from cradle to site using the ReCiPe 2016 method and the ELCD 3.2 database to evaluate the environmental impacts of expanding a 9.6 km highway from two to four lanes using hydraulic concrete. The project connects the capital city with a developing Pacific port and is strategically important for national logistics. Results show that the construction phase—particularly the paving stage—generates the greatest environmental burden, mainly due to the intensive use of cement, steel, and diesel. Eleven impact categories were analyzed and grouped into Emissions, Resource Depletion, Ecosystem Damage, and Human Health. Significant local impacts include PM_2.5 emissions exceeding national limits, while global impacts relate to high carbon footprint and energy use. Although limestone scarcity is not critical in El Salvador continuous extraction of aggregates poses risks to ecosystems and slope stability. These findings highlight the need to integrate LCA into infrastructure planning, especially in contexts where traditional EIAs overlook upstream impacts. The study demonstrates how LCA can reveal hidden environmental burdens and support more sustainable decision-making in road development. It also underscores the urgent need for national construction databases and capacity building among environmental and engineering professionals.