Procurement of more environmentally sustainable materials for civil infrastructure can be supported using environmental product declarations (EPDs). An EPD is a standardized label that is a scientifically sound way to communicate the potential environmental impacts and selected resource use and waste production flows from all or part of the life cycle of a product. To be called a Type III EPD, the life cycle assessment (LCA) for products used in civil infrastructure must be performed in accordance with ISO standards and the relevant product category rule (PCR) for the product type. Most EPDs for civil infrastructure materials in North America are “cradle-to-gate”, i.e., they include the impacts from the extraction of raw materials from the earth and end at the point at which the product is ready to leave the gate of the last manufacturing location. The steps leading to publication of an EPD include: 1) Developing the PCR, 2) Developing the LCA for the EPD, 3) Creating the EPD, and 4) Verification and publishing of the EPD. Industry-average, regional-average, product-specific, and facility-specific EPDs—with differing specificity to a particular product—are used for different purposes. EPDs are a source of data for materials impacts for use in assessment of the complete life cycle. They provide information to identify changes in impacts that can be made early in the materials production. They also can be used to help procure lower impact materials. This white paper discusses benefits of using EPDs and makes recommendations for improving their validity. Several areas needing improvement in current use in procurement are identified and recommendations are presented for improving the use of cradle-to-gate EPDs in transport infrastructure construction materials procurement and to provide input to complete life cycle pavement LCA to support decision-making.

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More than 90 percent of the road and highway network in the United States is paved with asphalt concrete. Maintenance and periodic rehabilitation require a continuous supply of aggregates and asphalt binder, both of which are becoming increasingly scarce and expensive. Recycling and reusing these resources can reduce costs and improve sustainability. The most common recyclable material used in road construction is reclaimed asphalt pavement (RAP), which is milled asphalt surface layers that have been removed from existing pavements before new asphalt overlay is placed. Reclaimed asphalt roofing shingles (RAS) are another potential source of asphalt binder.

There is growing interest in allowing significantly higher percentages of RAP and RAS in asphalt mixes used on state and local roadways. However, making this change has raised concerns regarding how these composite binders may influence the performance and durability of asphalt mixes, depending on the blends of different virgin and reused binders. Researchers at the UC Pavement Research Center investigated the use of higher percentages of RAP and RAS as a partial replacement for the virgin binder in new asphalt mixes and their effect on pavement performance in California. This research brief summarizes findings from that study.

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“Complete streets” are those designed not only to accommodate private vehicles, but also to enable safe access for all users, including pedestrians, bicyclists, and transit riders of all ages and abilities. Complete streets can contribute to increased transportation choices, economic revitalization, improved return on infrastructure investments, livable communities, improved safety, improved public health through promotion of active transportation, greenhouse gas reductions, and improved air quality. In 2018, researchers developed a life cycle assessment (LCA) framework for complete streets to enable planners and policymakers to quantify environmental and social impacts over the life cycle of a complete streets project. In this follow-on project, the researchers applied the framework to three case studies covering urban, suburban and rural/suburban regions/conditions. The researchers assessed whether the LCA framework was useful in identifying whether a complete street delivered or, in the case of a proposed project, was likely to deliver, the intended performance and benefits, and the social and health conditions of the neighborhoods receiving the benefits.

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The range of efforts to address climate change can span from international collaboration to personal action. This study looks at environmental efforts at the local jurisdictional level. Over the last decade, cities and counties have released climate action plans (CAPs) to set emissions reduction targets and outline actions that will help meet those goals. However, the range of information included in CAPs varies dramatically across jurisdictions. This study examines CAPs released by jurisdictions in California, focusing on the quantity and quality of information presented on the expected GHG emissions reduction, cost, and equity impacts of proposed climate actions. This research develops a framework to assess their inclusion, which could also be used to guide future CAP development, and develops a set of guiding questions to promote the inclusion of equity themes in climate action planning and implementation. To gauge the current state of climate action by local jurisdictions, a survey was implemented to better understand the (i) relative consideration of factors in climate action planning and implementation, (ii) factors which affect the inclusion of equity in climate action, (iii) the primary sources of funding for CAP implementation, and (iv) which factors affect the likelihood that an action is implemented. The survey found that, of the considered factors, expected emissions reduction is considered most during planning and implementation, while external impacts are considered the least. When comparing factors between planning and implementation, cost is significantly more important during implementation. For both phases, equity impacts received average levels of consideration. Free responses revealed that recent pushes by community members has encouraged local jurisdictions to include more equity themes in their climate planning. However, lifecycle equity, which considers local impacts across the lifecycle of an action, and thus beyond jurisdictional borders, is considered infeasible due to resource limitations and beyond the scope of local planning. Better equity planning would require systemic change at the jurisdiction, industry, state, and federal levels.

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The freight system is a key component of California’s economy, but it is also a critical contributor to a number of externalities. Different public agencies, private sector stakeholders, and academia engaged in the development of the California Sustainable Freight Action Plan (CSFAP). This plan put forward a number of improvement strategies/policies. However, the freight system is so complex and multifaceted, with a great number of stakeholders, and freight operational patterns, that evaluating or assessing the potential impacts of such strategies/policies is a difficult task. To shed some light, this project develops a freight system conceptualization and impact assessment framework of the freight movements in the State. In doing this, the framework assesses the impact of commodity flows from different freight industry sectors along supply chains within, originating at, or with a destination in the state of California.

The conceptual framework analyzes the freight flows in supply chains, and the type of freight activity movements and modes. The framework uses a Life Cycle Assessment (LCA) Methodology. The framework could be extended to support multidimensional cost/benefit appraisals for both direct benefits (e.g., delays, costs, accidents, maintenance) and social benefits to non-users which include impacts on regional and national economies as well as environmental and health impacts. This report discusses the main components of the conceptual framework based on a comprehensive review of existing methodologies. The implementation is limited to the Life Cycle Impact Assessment (LCIA) following the Environmental Protection Agency’s Tool for Reduction and Assessment of Chemicals and Other Environmental Impacts (TRACI).

The report describes the results from the LCIA implementation for a number of case studies. Specifically, the work estimated the impacts of moving a ton of cargo over a mile for various industry categories and commodity types. These results show the relative difference across industries and commodities and could serve to identify freight efficiency improvement measures in the state of California.

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Complete streets are those designed not only for private vehicles, but also to enable safe access for all users, including pedestrians, bicyclists, motorists, and transit riders of all ages and abilities. Specific street designs vary based on the type of street. Complete streets are intended to improve non-motorized travel safety, reduce costs and environmental burdens, and create more livable, sustainable, and economically vibrant communities. Investment in complete streets projects is growing around the country with these goals in mind. However, there are limited data to verify the effectiveness of complete streets, and the indicators required for quantification of complete street performance are not yet agreed upon. Complete street sustainability indicators are important to assess whether a complete street conversion is achieving its goals and to support decision-making for complete street investment.

Researchers at the University of California, Davis and JCH Research used life cycle assessment, a modeling tool for evaluating a product or activity’s environmental impacts through all stages of its life, to quantify the environmental performance of complete streets. The researchers also reviewed the academic literature for social impact indicators, which have generally not been well developed in life cycle assessment applications. The researchers adapted these indicators to better consider equity, guided by interviews with a diverse set of stakeholders. Complete street typologies compiled from several sources were used to test and refine the life cycle assessment framework for complete street conversions. This policy brief summarizes the findings from that research.

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