The environmental impacts of infrastructure are often neglected in large transport projects, yet it is precisely there that considerable potential for ecological improvement can be found. This work integrates environmental impacts into the life cycle management (LCM) of railway infrastructure, combining condition assessment, life cycle assessment (LCA) and life cycle costing into a holistic framework. Using Austrian boundary conditions, the greenhouse gas emissions of the entire network are quantified, revealing that infrastructure provision causes emissions nearly equal to those of daily rail operations. Detailed LCAs identify the main emission drivers and demonstrate that service life is the decisive criterion of sustainability. A decision-making model internalises environmental costs alongside life cycle costs, and a critical-value approach handles uncertainties. Case studies on ballast quality, under-sleeper pads and slab versus ballasted track show that durability-oriented strategies reduce both costs and emissions. The work highlights concrete projects – hydrogen for track construction, green procurement, and innovative ecological construction methods – demonstrating that potential can be unlocked through planning, procurement, technology and asset management.