Supporting urban sustainability through resilient rail transit systems

Urban rail transit is vital to supporting urban sustainability across environmental, economic, and social pillars. However, recent extreme weather events, particular flooding, have increasingly disrupted its operations, highlighting the urgent need to strengthen system resilience. Developing comprehensive resilience assessment methods with results of practical relevance is essential for evaluating the system's capacity to withstand and recover from such disruptions, using quantifiable impacts across physical, operational, social, and economic dimensions. While resilience and sustainability are often discussed together in the context of climate change, methodologies for integrating sustainability considerations into resilience assessments to develop informed adaptation strategies remain underdeveloped. Drawing on the UN Sustainable Development Goals, this commentary examines the relationship between resilience and sustainability in the urban rail transit sector under disruptions related to natural disasters and climate change. Following this, it proposes a three-tier network modelling roadmap for assessing the resilience of urban rail transit, illustrating how sustainability concerns can be incorporated into resilience planning. This roadmap progresses from current mainstream topology-based approaches to a state-of-the-art performance-oriented method, and ultimately to a forward-looking vision that integrates socio-demographic considerations and prioritises equity. Positioned at the infrastructure-disaster-society nexus, this commentary advocates embedding a systemic view in transport network modelling to yield actionable resilience strategies that address extreme weather events while promoting urban sustainability.