Members of the BSCES Committee on Sustainability
The Commonwealth of Massachusetts now has an Embodied Carbon Reduction Plan, in January 2026, applicable to state-managed construction projects! The document was prepared by the Embodied Carbon Intergovernmental Coordinating Council (ECICC). The document is pursuant to MGL Part I, Title II, Chapter 7C, Section 73.
Carbon is everywhere. It’s an important “building block of life.” Carbon is essential for living organisms. It is also essential is products we use every day. So, why are we talking about reducing embodied carbon? Embodied carbon refers to all greenhouse gas emissions produced/generated for a material over its lifetime, from “cradle to grave.” The two most common materials used in infrastructure projects are concrete and steel. Using a steel beam as an example, the embodied carbon is the total amount of greenhouse gases emitted from extraction of the ore, transportation to process plants, emission from energy from all the processing to make the steel, then making it into the steel beam. Followed by transportation to the construction site and erection of the steel beam. At the end of the service life of the steel beam, the emissions caused from removing the and disposing of the beam are counted. The total of the emissions is measured as kilograms of CO2e per kilogram of material.
This article encourages all engineers and constructure teams and operators of infrastructure projects to learn more about the embodied carbon for infrastructure projects. There are many ways of reducing embodied carbon. Just as we have worked to deal with other infrastructure challenges, we can address through understanding the embodied carbon inputs into the materials, design, construction, location, environmental impacts, weather conditions, design loading, resilience requirements and durability to name a few.
Understanding the embodied carbon in the materials is where many of us begin. For a steel beam, the embodied carbon is reduced with a high recycled content. It is increased when fossil fuels in a blast furnace are used. Is it locally produced? Does it arrive by barge? An environmental product declaration (EPD) provides information about the embodied carbon in the manufacture of the material. Steel manufacturers have been producing “product specific EPDs.” If these are not available, there are ranges of embodied carbon for the materials used in the project area.
The location of a project can play a role in the embodied carbon. For example, determination of a new bridge crossing a river may have several possible sites. Though this work occurs before final design, it is recommended to calculate a rough embodied carbon footprint for each alternative. The different sites may have different pier locations and different span lengths. The alternative may have multiple types of bridges, such as steel truss or pretensioned precast concrete beams. The embodied carbon of the alternatives may or may not be a deciding factor for the site selection, but it could be used as a baseline. The final design’s embodied carbon could be measured against the baseline.
The construction of a bridge plays a role in the embodied carbon. Often the lower concrete compressive strengths have lower embodied carbon than the high strengths. The foundations for bridge peers can save on embodied carbon simply by using a lower compressive strength. A strategy of looking at various material strengths and their embodied carbon helps engineers and contractors reduce the overall project embodied carbon by weighting its importance.
In many ways, infrastructure projects by their nature of the uses are inherently efficient and robust. The average service life of a bridge is seventy-five years. Designing the bridge for the loading it will see over the service life whether it be seismic, climate hazards, or other disasters, is best.
Keep in mind, the reduction of materials during the final design process is a strategy, but it doesn’t address the full picture. It is important to bring engineers, contractors, planners, and professionals from each stage of the infrastructure life cycle to support the development of solutions. This is true for all types of infrastructure projects from tunnels, wastewater, ports, bridges, roadways, transit, airports, more. The infrastructure of our communities is important to its vitality. At the same time, the greenhouse gases in our atmosphere are heating the earth.
This article is an invitation to infrastructure engineers, contractors, planners and owners of all types of infrastructure to contribute to the reduction of embodied carbon.