This dissertation consists of three interrelated empirical studies on active transportation planning, the built environment, and pedestrian behaviors in Hong Kong and the San Francisco Bay Area. Through two independent case studies and one comparative study, I examine three overarching research questions: 1) what is the role of social media in facilitating civic urbanism for active transportation? 2) how are active transportation plans associated with the built environment over time? 3) how do pedestrian behaviors differ across cultures? I employ various data and analytical methods to answer these questions.

I first survey the institutional contexts for active transportation planning in Hong Kong and the Bay Area before delving into the three empirical studies in the following three chapters. The active transportation planning process in Hong Kong manifests a complex interplay between the government and civil society, a multifaceted process involving public participation, economic incentives, institutional organization, planning culture and politics. Contrary to the territory-wide strategic plans in Hong Kong, the Bay Area jurisdictions adopt city or county-level master plans for bicycle and pedestrian environment improvements.

The first study examines the use of social media by local placemaking non-governmental organizations (NGOs) in Hong Kong, and its role in facilitating public participation processes in active transportation planning. It utilizes social media texts and in-depth interviews with stakeholders to gauge opinions towards active transportation issues in Hong Kong, as well as how the NGOs employ social media as a tool to engage the public around active transportation agendas especially when formal participation channels exhibit limited capacity. The findings reveal the role of social media as a critical outlet for advocacy and a collaborative decision-making process. The case also demonstrates the opportunities for governmental agencies to collaborate with civil society organizations for more people-centric active transportation planning. However, to build the trust that supports such collaboration requires substantial work.

The second study sits in the context of the San Francisco Bay Area. It uses a mixed method approach to investigate the trends and implementation pathways of pedestrian infrastructure enhancements around BART and Caltrain stations in the San Francisco Bay Area. It utilizes several novel datasets generated from unstructured data with statistical modeling, to systematically examine the built environment changes and their association with plans at a high spatial-temporal resolution. It demonstrates the potential role of plans in instigating changes in marked crosswalks at station area intersections, as well as the interactive effects contributed by a variety of station area characteristics. The upgrading and addition of high-visibility crosswalks show an overall improvement of pedestrian environment, suggesting the effectiveness of the presence of master plans.

The third empirical chapter presents a comparative study of pedestrian behaviors across Hong Kong and the San Francisco Bay Area. It utilizes a comprehensive dataset on behavior, infrastructure, and environment for the pedestrians collected at 283 heavy rail station areas, to understand the nuances of pedestrian interaction with human scale environment across two seemingly different cultures for walking in the context of contrasting urban form, car-dependency, as well as the perception of walking. The findings highlight the importance of observing the context-specific nuances in human-centric urban design. First, the types of pedestrian infrastructure and ambient environment surrounding transit-access pedestrians present more similarities than differences across cultures. Second, a typical pedestrian in Hong Kong and San Francisco appears to behave in a similar manner given a comparable level of perceived stress and risk from cars. Third, regions differ in their choices of design treatments for a specific road or traffic flow condition. However, I document how this sometimes may lead to counter effective or unintended results.

Altogether, the three studies contribute a comprehensive story about the state-of-the-art practice of active transportation planning in a global context. It shows how different policy contexts shape the roles of prominent stakeholders in the active transportation planning process. The two-case comparison extends findings from single case studies in terms of how urban design transfer or deviate from place to place. In order to achieve active transportation-friendly environment, design strategies should not be taken at face value without examining the human-scale nuances such as walking speed or compliance with traffic rules.

The COVID-19 pandemic has caused unimaginable adversity, with nations across the globe devising ways to cope with the loss of life, economic productivity, and social fabric. Due to the agnostic nature of the virus, no facet of society, whether in the Global North or South, has been left untouched. As beacons of economic and social agglomeration, the pre-pandemic city, in particular, has seen a rapid transformation, in often unforeseen directions. Local businesses have shuttered, while large technology companies have thrived; offices have closed, while their adjacent streets have been opened for active mobility and social activities; apartment rents have decreased, while single-family home prices have increased; the underprivileged have been adversely affected by both the virus as well as the economic reality of the pandemic, while the affluent have been largely untouched in both health and economy. Responses to COVID-19 in various nations have only exacerbated existing socioeconomic inequities, and, expectedly, not all federal, state, or local responses have been beneficial to all strata of society. This white paper focuses on several core themes that have evolved over the course of the pandemic and have behaved differently across geographies: (1) urban economics and equity (2) social and economic power dynamics, and (3) strategies to preserve urban social and economic systems.