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Open Access Publications from the University of California
Cover page of Framework for Urban Metabolism and Life Cycle Assessment of Hardscape

Framework for Urban Metabolism and Life Cycle Assessment of Hardscape

(2018)

Urban hardscapes can be defined as human-altered surfaces in contact with the earth in urban areas other than alterations for horticulture. Hardscape covers large portions of the urban surface area, and has potentially large influence on air emissions, truck traffic and its associated problems, and the potential for flooding. Modeling the inflows of hardscape materials and the outflows of demolished hardscape and other rock-based products from buildings and other civil infrastructure is expected to provide a means to find solutions for reducing these flows and their impacts. Modeling of urban hydrology with respect to the effects of hardscape on surface and groundwater flows from precipitation is expected to provide a means to find solutions that will reduce the risk of flooding and improve groundwater recharge.

The goal of this white paper is to advocate that researchers and policy-makers use the analytical approach of combining urban (UM), material flow analysis (MFA) and elements of life cycle assessment (LCA) to measure and improve the efficiency of urban hardscape in large urbanized areas with respect to environmental impacts affecting global warming, safety and quality of life through use of alternative hardscape structure and materials and more permeable hardscape. The white paper provides details on the proposed UM-LCA framework. Additionally, several data sources and modeling tools were identified that can be used in the UM-LCA framework to quantify material and energy flows and environmental impacts including water flows. An effort was also made to identify data for a few of the cities in California in order to demonstrate parts of the data collection and presentation process. The framework developed is not limited to a single U.S. state, rather it can be used in any geographic region of the U.S.

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Cover page of Transit-Oriented Development Opportunities Among Failing Malls

Transit-Oriented Development Opportunities Among Failing Malls

(2018)

This paper explores opportunities for the redevelopment of failing regional shopping malls as Transit-Oriented Developments (TODs) to improve transit ridership, focusing on Southern California. In effect, the study suggests an alternative to the typical sequence of first providing transit infrastructure and then changing land uses and densities to develop a TOD around new transit stations. Instead, the study suggests that failing shopping malls can provide the footprint for their redevelopment as TODs that could then be linked to transit lines. The study focuses on several major topics and reviews recent literature on the following steps in the argument for this policy:

1. The rationale for redeveloping declining malls as TODs, the supporting federal and California policies for TODs, and evidence for how different characteristics of TODs and their combination can reduce vehicle miles traveled, air pollution, and greenhouse gas emissions;

2. The issues that hinder the development of TODs around transit stations, e.g., difficulties in up-zoning, land assembly; loss of existing affordable housing;

3. Changes in retail, focusing on factors affecting the closing of shopping malls, e.g., the effect of Internet shopping on shopping malls, and the increasing failure of shopping malls; and

4. The potential and rationale for the redevelopment of failing regional malls into TODs.

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Cover page of Incorporating Long-Distance Travel into Transportation Planning in the United States

Incorporating Long-Distance Travel into Transportation Planning in the United States

(2018)

In the early years of transportation planning and highway infrastructure development in the United States the focus was on intercity or long-distance travel, a contrast to the metropolitan travel and state-based models that dominate today. Daily home and work-based travel, which have been the focus of data collection and models since the 1950s, are well-modeled by regional agencies and a limited number of state travel demand models even include some long-distance travel. Nonetheless, long-distance travel demand and factors affecting behavior are not thoroughly considered in transportation planning or behavior research. Only one recent activity-based model of national travel demand has been created and its scope was limited by a severe lack of data. The conceptualization of models to consider intercity long-distance travel has changed little since its inception in the 1970s and 1980s. In order to comprehensively consider transportation system sustainability, there is a critical need for improved nation-wide annual overnight activity data and models of overnight travel (a re-focus and important distinct re-framing of long-distance trips that this white paper suggests).

Truly addressing the economic, environmental, and social equity issues required to create a sustainable global transportation system will entail completely updating our existing planning framework to meaningfully include long-distance travel. It is clear that long-distance passenger miles must be accounted for when addressing greenhouse gas (GHG) emissions and other negative environmental externalities. Less well-known are the questions of social justice that loom large when one considers the details of long-distance travel. Travel in our society is becoming increasingly associated with quality of life. Those without intercity access may miss opportunity and social capital. However, without representative long-distance travel data it is impossible to compare the relative participation by different groups and to consider latent demand. It is difficult to measure who comprises the global mobile elite and who lacks sufficient intercity mobility for reasonable social network obligations and personal services.

This white paper suggests utilizing a common framework for long-distance data collection and tabulation that re-defines long-distance travel into daily or overnight. The author advocates using overnight as the defining characteristic for data collection, which complements existing daily travel surveys already capturing long day-trips. Within frameworks moving forward it is important to clearly characterize all trip purposes, including mixed purposes and purposeless travel, which comprise an appreciable portion of long-distance travel. Spatial data that distinguish between simple out-and-back trips and spatially complex trips are necessary and mobile devices have now made this measurement of long-distance tours feasible. In order to truly model all travel in the current system, we must move away from the idea that most travel is routine, within region, and home-based. Many people, especially the most frequent travelers, have long-distance routines including multiple home bases. Additionally, our models should not assume that travelers staying at a second home, hotel, or friend’s home travel like residents. Efforts to measure and model non-home-based travel or travel at destination are essential to accurately modeling behavior. Daily surveys such as the 2017 National Household Transportation Survey are increasingly doing this. A nation-wide annual activity model of overnight travel must fully incorporate both surface and air travel to allow full consideration of alternative future system scenarios.

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Cover page of Onboard Feedback to Promote Eco-Driving: Average Impact and Important Features

Onboard Feedback to Promote Eco-Driving: Average Impact and Important Features

(2018)

Driver behavior has an immense impact on vehicle fuel economy and emissions, yet it has historically been treated as random error in models of fuel economy and neglected in energy and environmental policy-making regarding fuel efficiency. Recently, concern about fossil fuel depletion and climate change, as well as the critical role of driver behavior in achieving the fuel economy benefits of new hybrid and electric vehicles, has created interest in eco-driving. Eco-driving refers to suites of behavior a driver can engage in to improve fuel economy.

The most common strategy used to promote eco-driving is feedback that conveys information about fuel efficiency to the driver. Feedback is typically visual and provided on-board the vehicle via digital screens (dash or instrument cluster displays, after-market devices, or web apps on personal smartphones or tablets). No policies exist requiring manufacturers to provide eco-driving feedback, yet feedback systems of increasing variety are appearing in vehicles, likely due to advances in telematics and decreasing costs of new technologies. The rapidly increasing prevalence and complexity of in-vehicle information systems, along with concern for driver distraction, suggest standardization of eco-driving feedback may be warranted in the near future. Thus, there is a need to understand what types of eco-driving feedback are effective.

This white paper presents a statistical meta-analysis of eco-driving feedback studies in order to determine a pooled estimate of the impact on fuel economy and explore how characteristics of feedback interventions influence their impact. It provides the most accurate estimate to-date of the average impact of in-vehicle feedback on fuel economy and summarizes the current state of knowledge regarding characteristics of eco-driving feedback interventions that determine effectiveness.

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Cover page of Sustainable Transportation Implications of On-Demand Ride Services

Sustainable Transportation Implications of On-Demand Ride Services

(2018)

The motivations for this study stem from an uncertainty about whether on-demand ridehailing services such as Uber, Lyft and others, will exacerbate existing transportation issues, or help alleviate them. To that end, the goals of the project were to learn about the perspectives of stakeholders from a variety of sectors, on their reactions to policies and other actions that might enable on-demand services to help alleviate existing transportation issues including congestion, emissions and inequality of access and mobility.

This study aims to address the following three questions: How well do stakeholders in different sectors and regions, agree about the potential outcomes related to on-demand ridehailing and sustainable transportation goals? What are stakeholder perspectives on the policies and strategies that might facilitate emerging on-demand transportation services to most effectively enhance sustainability and mobility outcomes? What decision making venues and approaches are supported by different stakeholders in the process, and how can these approaches be pursued in order to realize policy goals related to sustainability of on-demand ridehailing? I.e., what venues, and at what level can most effective policies be introduced to facilitate sustainability improvements in transportation by embracing on-demand ridehailing services.

To answer these questions, a series of interviews were completed with stakeholders from California Metropolitan Planning Organizations (MPOs) and Regional Transportation Planning Agencies (RTPAs), from state agencies, the ridehailing industry, and local planning agencies or transportation divisions of cities. The results of this study indicate that policy makers must consider the varied systems and contexts throughout the state; and likely throughout the US. Further, there is an existing dialogue on these topics among transportation professionals, public interest groups, academics and policy makers. In this study, the researchers took a systematic approach to documenting this dialogue and identifying meaningful messages and policy guidance that is not possible without a rigorous scientific approach.

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Cover page of Steering the Electric Vehicle Transition to Sustainability

Steering the Electric Vehicle Transition to Sustainability

(2018)

To achieve carbon reduction goals for 2040 and 2050, plug-in electric vehicle (PEV) policy must be worldwide and involve multi-decade policy programs. One policy is a broadening commitment to ending fossil fuels for light-duty vehicles; this will solidify the direction and accelerate investments in zero emission vehicles (ZEVs) and decapitalization of internal combustion drivetrain production so as to enable the climate driven timetable of the transition. Another proposed policy is up to two decades of financial signals to buyers and producers, sized to keep the market tilted toward PEVs while production costs decline. Additional privileges in road, parking and electricity systems are needed to attract more conservative segments of buyers and sellers. PEV manufacturers could commit to at least three generations of PEV design, and investment and product rollout into all market segments and vehicle designs. Outreach and education campaigns lasting through those three generations of potential consumers could also be implemented, including leveraging the enthusiastic desire of the first few million buyers to educate coworkers and neighbors. Inclusion of energy transitions in the education system is also necessary. The retail sector, primarily dealers included in the policy, could also have education and incentive programs. Efforts of OEMs, governments and power companies could be coordinated to meet charging needs and wants of the expanding market. This will need to include the greening of the grid and integration of PEVs in the system optimization of renewables.

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Cover page of Travel Effects and Associated Greenhouse Gas Emissions of Automated Vehicles

Travel Effects and Associated Greenhouse Gas Emissions of Automated Vehicles

(2018)

In much the same way that the automobile disrupted horse and cart transportation in the 20th century, automated vehicles (AVs) hold the potential to disrupt our current system of transportation and the fabric of our built environment in the 21st century. Experts predict that vehicles could be fully automated by as early as 2025 or as late as 2035. The public sector is just beginning to understand AV technology and to grapple with how to accommodate it in our current transportation system.

Research on AVs is extremely important because AVs may significantly disrupt our transportation system with potentially profound effects, both positive and negative, on our society and our environment. However, this research is very hard to do because fully AVs have yet to travel on our roads. As a result, AV research is largely conducted by extrapolating effects from current observed behavior and drawing on theory and models. Both the magnitude of the mechanism of change and secondary effects are often uncertain. Moreover, the potential for improved safety in AVs drive the mechanisms by which vehicle miles traveled (VMT), energy, and greenhouse gas (GHG) emissions may change. We really don’t know whether AVs will achieve the level of safety that will allow for completely driverless cars, very short headways, smaller vehicles, lower fuel use, and/or reduce insurance cost. We don’t know whether AV fleets will be harmonized to reduce energy and GHG emissions.

In this white paper, the available evidence on the travel and environmental effects of AVs is critically reviewed to understand the potential magnitude and likelihood of estimated effects. The author outlines the mechanisms by which AVs may change travel demand and review the available evidence on their significance and size. These mechanisms include increased roadway capacity, reduced travel time burden, change in monetary costs, parking and relocation travel, induced travel demand, new traveler groups, and energy effects. They then describe the results of scenario modeling studies. Scenarios commonly include fleets of personal AVs and automated taxis with and without sharing. Travel and/or land use models are used to simulate the cumulative effects of scenarios. These models typically use travel activity data and detailed transportation networks to replicate current and predict future land use, traffic behavior, and/or vehicle activity in a real or hypothetical city or region.

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Cover page of The Economic Benefits of Vehicle Miles Traveled (VMT)- Reducing Placemaking: Synthesizing a New View

The Economic Benefits of Vehicle Miles Traveled (VMT)- Reducing Placemaking: Synthesizing a New View

(2017)

This paper analyzes evidence on the economic benefits of placemaking efforts that prioritize pedestrian and non-motorized access and that, at times, reduce vehicle miles traveled. The previous literature on the economic impacts of transportation has focused on theorizing and gathering evidence on ways that transportation infrastructure generates economic benefits at large geographic scales–often states or nations. That literature overlooks many of today’s transportation projects which are at the scale of a neighborhood and which typically include non-motorized transportation. The authors summarize evidence on how those more locally oriented placemaking efforts are associated with benefits that accrue to residents and firms. There is a high degree of evidence that there are economic benefits, on commercial property values, residential property values, business sentiment, and productivity, from density that are summarized as they relate to neighborhood oriented placemaking transportation policies. The authors conclude by suggesting a systems view of metropolitan transportation that has a hierarchy of networks, from high-throughput metropolitan arteries to local, multi-modal, neighborhood planning with connections between the different levels of the system.

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Cover page of Affordable Housing in Transit-Oriented Developments: Impacts on Driving and Policy Approaches

Affordable Housing in Transit-Oriented Developments: Impacts on Driving and Policy Approaches

(2017)

This paper studies the intersection of policies promoting affordable housing, transit-oriented developments (TODs), and the reduction of vehicle miles traveled (VMT) in metropolitan areas. In particular, this paper focuses on the following questions: 1. Does locating affordable units in TODs increase or decrease VMT and thus emissions? 2. Is affordable housing in TODs still affordable in the long-term, i.e., beyond the expiration of the first minimum affordability period? 3. Do the benefits of affordable housing near transit outweigh the frequently higher costs of development in TODs? 4. What policy recommendations emerge from the analysis?

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Cover page of Examining the Safety, Mobility and Environmental Sustainability Co-Benefits and Tradeoffs of Intelligent Transportation Systems

Examining the Safety, Mobility and Environmental Sustainability Co-Benefits and Tradeoffs of Intelligent Transportation Systems

(2017)

In this whitepaper, the authors briefly describe the three major MOEs, followed by a categorization summary based on the most recent literature. Next, a number of typical CAV applications have been examined in depth, providing a detailed analysis of the different MOEs co-benefits and tradeoffs. Further, three representative CAV applications have been examined in detail in order to show the association between the application focus and tradeoffs/co-benefits of different performance measures. The CAV applications include High Speed Differential Warning (safety-focused), Lane Speed Monitoring (mobility-focused), and Eco-Speed Harmonization (environmental impacts-focused). The authors then highlight several future research directions, including the identification of key influential factors on system performance and how to obtain co-benefits across all key MOEs. The overall intent of this whitepaper is to inform practitioners and policy makers on the potential interactions between the safety, mobility, and environmental sustainability goals of implementing specific CAV applications as part of their ITS programs.

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