| Résumé | This document provides a national framework and practical guidance for conducting Life Cycle Assessment (LCA) of Canadian highway bridges. The purpose is to establish a harmonized and consistent methodology for quantifying the environmental impacts of bridges across their entire life cycle—from design and construction through maintenance, repair, and end-of-life phases— with particular emphasis on greenhouse gas (GHG) emissions. This Guideline is a foundational step toward integrating environmental performance into bridge planning and design, promoting more sustainable infrastructure across Canada.
The Guideline serves following key objectives:
• Standardize the practice of Bridge LCA across Canada to improve comparability, transparency, and quality of assessment.
• Support integration of LCA into bridge design practices, including future incorporation into the Canadian Highway Bridge Design Code (CSA S6).
• Enable alignment among Bridge LCA tools and datasets through a common framework and terminology.
• Facilitate using LCA in infrastructure policy, funding eligibility, and environmental compliance programs to support Canada’s climate and sustainability goals.
This document is intended for users across the bridge construction value chain, including policymakers, infrastructure planners, bridge owners and operators, design engineers, material suppliers, LCA practitioners, and tool developers.
The methodology presented aligns with international standards ( ISO 14040:2006 and ISO 14044:2006) and adheres to the four classical phases of LCA: goal and scope definition, inventory analysis, impact assessment, and interpretation.
The document is structured as follows:
• Chapter 1 outlines the background and rationale for conducting Bridge LCA in the Canadian context.
• Chapter 2 provides an overview of various bridge systems, the life cycle of a bridge, and stakeholder engagement in LCA.
• Chapter 3 defines the goal and scope of a bridge LCA, including functional unit, system boundaries, and life cycle stages (A0–C4).
• Chapter 4 provides detailed guidance on life cycle inventory (LCI) data collection and treatment, including both generic and project-specific inputs.
• Chapter 5 provides recommended data and models to be used for LCI and LCIA specifically related to GHG intensity.
• Chapter 6 provides methodological guidance for estimating environmental impacts using life cycle impact assessment (LCIA) methods.
• Chapter 7 offers best practices for interpreting LCA results to support informed decisionmaking.
• Chapter 8 offers best practices for reporting LCA results to stakeholders.
• Chapter 9 contains appendices related to supplementary LCI data, sample data set and calculations, allocation methods and references to commonly used LCA tools. |
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