Abstract Manager

To assess how the construction of new rail infrastructure can be optimized to reduce overall city transportation emissions and improve carbon payback over the project lifecycle, a greenhouse gas (GHG) mitigation assessment was completed. This assessment was completed in support of the Federal Climate Lens application, a framework for infrastructure projects to meet Canada’s climate goals. This paper describes a multidisciplinary approach that was applied by considering GHG emissions from key elements in rail infrastructure such as tunnelling, guideways, and stations. Guided by PAS 2080, this set out a wider lens to address emissions from Capital, Operational, and User carbon which highlights the complex cross-sector interactions between transportation, materials, GHG emissions, construction, investments, and much more.

The GHG mitigation assessment provided the project team a clear understanding of the main contributors to carbon across the asset’s service life and established the carbon baseline. The insights on Capital and Operational carbon were used to evaluate mitigation strategies and to establish specific reduction targets within the Project Agreement. The results were used to rank carbon reduction strategies based on their greatest reduction potential, which was paired with a high-level cost, schedule, and feasibility evaluation of each carbon reduction. These mitigation measures included GHG reductions in concrete, incentivization to minimize construction emissions, evidence of planning and tracking towards GHG reductions, and collection of as-built information. Ultimately, this study informed the performance-based requirements embedded in the technical specifications which will hold the design-build team accountable to the overall carbon budget for the project while allowing them flexibility and creativity in how to achieve the climate goals of the project, agency, and wider region.