This research proposed a tool for guiding the approach and practice for sustainable design and management of transportation projects. The tool intends to identify and select design and management alternatives for sustainable roadways, bridges, and transit projects. A primary objective is to lower the carbon footprint of Core Public Infrastructure (CPI) projects in a changing climate for the entire lifecycle of projects, based on Lifecycle Assessment (LCA) principles. The analysis followed three steps:
A. Review of Lifecycle Assessment (LCA) of infrastructure in terms of the triple bottom line (TBL). The literature review on infrastructure LCA methodology and transportation infrastructure LCA methodology provided an overview of the state-of-practice. It identified constraints and gaps in addressing the full range of sustainability (environmental, social, and economic).
B. Review of sustainability assessment in terms of the lifecycle of a project.
An analysis and cross-examination of the most widely used sustainability certification systems (Envision®, CEEQUAL®, and ISCA®) determined the extent of considering lifecycle within the sustainability rating process and identifies gaps.
C. Presentation of a transportation infrastructure project.
A small-scale typical bridge replacement project by the Ministry of Transportation of Ontario (MTO) provided input for the research. The bridge project served as a vehicle to:
• provide insight into the context of sustainability practice in transportation projects in Canada;
• identify the environmental, social, and economic impacts of transportation projects and present priorities, needs and strategies, and potential areas for improvement in managing inevitable trade-offs in the lifecycle performance of assets;
• calibrate a sustainability rating system’s methodology in terms of how the lifecycle stages and TBL impacts of a transportation project are taken into consideration, and
• calibrate the proposed model through its application on a project that provided both input and an example of use.