This session offers posters for a selection of papers involving public transportation and the built environment, accessibility, and equity considerations.
Assessing Changes in Accessibility and Its Impact on Rent-Burdened Households
Brian Waterman, HDRShow Abstract
Lauren Adams, HDR
Kohl Malo, Renaissance Planning Group
Kaisha Rose, HDR
The purpose of this paper is to analyze the relationship between affordable housing and transit by looking at how system redesigns affect accessibility to destinations. The premise is that improved accessibility to jobs and key destinations (social services, medical, dental, etc.) lowers transportation costs for households, improving the affordability of cites. This is a case-study analysis of three transit systems who have conducted a major redesign of their transit system. It uses ArcGIS Network Analysis to assess changes in travel time to jobs and key services for rent-burdened individuals and affordable housing residents. The results are stratified by travel time and percent of income paid towards rent to show the number of destinations that are available within a 30 minute walking distance of a bus stop. The analysis showed that including a coverage-based component to the route design preserve access to these individuals and the improved accessibility leads to increases in ridership, leading to lower transportation costs. This study, however, does not quantify the change in travel behavior towards using transit post route redesign as a means to explain potential household savings. The next steps would be to look more closely at affordable housing communities and rent-burdened individuals in one of the cities and survey the individuals to see if the route changes led to them using transit more and how it is affecting their household budget. Further explaining this relationship would provide cities additional tools to address affordable housing needs in their communities.
Thinking regional and acting local: Assessing the joint influence of local and regional accessibility on commute mode in Montreal, Canada
Penelope Lussier-Tomaszewski, Ecole Polytechnique de MontrealShow Abstract
Genevieve Boisjoly (email@example.com), Polytechnique Montréal
Accessibility indicators, measuring the ease of reaching destinations via a specific mode of transport, are increasingly used in planning and research as they support integrated land use and transport planning. Research has shown that increased local accessibility (walkability for example) is associated with an increase in walking mode share, whereas increase in public transport accessibility is associated with a greater use of public transport. Yet, while public transport agencies are promoting the combination of active and public transport options to address one’s diverse mobility needs, local and regional accessibility are rarely addressed together in research or practice. This research aims to determine the joint influence of local and regional accessibility on the transport mode used for work trips in the Montreal metropolitan region, while controlling for socio-demographic characteristics. Data come from the 2013 Origin-Destination survey, 2016 Canadian census, 2017 public transport data and DMTI Enhanced points of interests. A multinomial logistic model is used to understand how local and regional accessibility are associated with walking, cycling or taking public transport to work across individuals. The results demonstrate that increases in both local and regional accessibility are associated with a higher probability of using sustainable modes. The predicted probabilities suggest that local accessibility is more closely associated with a decrease in car use. This study sheds light on the interaction between local and regional land use and transport systems and is of relevance to planners and policymakers wishing to develop neighborhoods that support the use of sustainable modes.
Urban Form and Transit Oriented Development (TOD): Comparison of Two Areas in Naples, Italy
Rahul Tiwari, Maulana Azad National Institute of TechnologyShow Abstract
Murthy Bondada, EPIC Engineering and Consulting LLC
Antonio Nigro, University of Naples Federico II
All over the world, increasing automobile trips and resulting negative consequences, such as traffic congestion, air pollution and accidents, have been a matter of concern. As a strategy to contain the automobile travel by shifting to Transit, a concept called Transit Oriented Development (TOD) has been propagated. TOD can basically be defined as high density, mixed-use urban development accessible within a few minutes of walk to a public transport stop or station. Cities across the world have implemented the TOD concept. Starting with the 1997 Transport Plan, the city of Naples, Italy has developed a strategy similar to TOD concept with rail Transit. This study makes a comparative analysis of two areas in the city with different urban forms in meeting the characteristics of the TOD concept: 1) the Centro Direzionale, alias central business district, located at the edge of the city center, and 2) the Municipio area, in the central core of the city. Although different in terms of urban morphology and historical value, these two areas are characterised by high density, mixed land use and good accessibility to rail transport. The aim of this study is to analyse socio-economic characteristics along with travel pattern of both the areas, in order to develop meaningful insights regarding the kind of urban form and its level of achieving the benefits of TOD concept. The paper will conclude with a set of recommendations, whether to implement high-rise cost intensive projects in the name of TOD or to preserve the conservative urban form.
Transportation Infrastructure as a Social Justice Issue: A Mixed Methods Analysis of a Suburban Boomtown
Jandel Crutchfield (firstname.lastname@example.org), University of Texas, ArlingtonShow Abstract
Erin Findley, University of Texas, Arlington
Courtney Cronley, University of Tennessee, Knoxville
Kate Hyun, University of Texas, Arlington
Mehrdad Arabi, University of Texas, Arlington
This sequential, mixed methods study used an interdisciplinary approach to assess the gaps between economic growth and transportation infrastructure development in a suburban boomtown. Suburban boomtowns are characterized by rapid population and economic growth, yet little is known about the commensurate infrastructure development and its impact on boomtown residents. This study analyzed one rapidly-growing county in North Central Texas, where population growth has increased over 100% since 2000. Researchers studied the extent to which transportation infrastructure has matched the region’s booming economic growth. Specific emphasis was placed on exploring the impact of potential gaps in access to opportunities – such as affordable housing, employment, health care, education and social activities – for those at risk of transportation disadvantage, referred to as environmental justice (EJ) populations. The research team, in partnership with the regional homeless coalition, conducted just over 200 surveys and four focus groups, with a sampling frame which included half EJ and half non-EJ residents. Quantitative and qualitative data were analyzed by the research team and paired with GIS mapping of the region’s growth between 1990-2017. Findings confirmed the presence of gaps in transportation infrastructure development relative to economic growth, as well as a disparate impact on opportunities for EJ populations. Study results offer insight into improving planning and co-development of transportation infrastructure alongside other forms of growth to enhance opportunity equity and sustainability in a suburban boomtown.
The Myth of the Captive Transit Rider: Do Transit Investments in Low-Income Neighbourhoods Matter?
Elnaz Yousefzadeh Barri, Istanbul Teknik UniversitesiShow Abstract
Steven Farber, University of Toronto, Scarborough
Eda Beyazit, Istanbul Teknik Universitesi
Transportation professionals have suggested improving public transit in low-income neighbourhoods to alleviate socio-spatial inequalities and increase quality of life. However, planners often overlook transit investments in neighbourhoods with transit-captive populations because they are assumed to result in less mode-shifting, congestion relief, and environmental benefits, compared to investments that aim to attract choice riders in wealthier communities. While many low-income households are already transit users, many also own and use private vehicles. Therefore, the main aim of this article is to explore the sensitivities of transit use among households with different income levels, with respect to transit accessibility and vehicle ownership levels in the Greater Toronto and Hamilton Area (GTHA). In this analysis, we adopt stratified modeling for households with different income and car-ownership levels to examine the disparity in taking transit. To further explore the impact of transit accessibility on choosing transit, we undertake a sensitivity analysis using those models. In the existing situation, low-income carless people are the most frequent transit users. After increasing accessibility for different income and car-ownership strata, we observe that car ownership has a higher impact on the number of new transit trips than income does. Moreover, in the case of low-income people, those investments do not result in a significant change in their travel mode because they either are already living in places with adequate transit services or are already transit users. Finally, we found that accessibility per se is not a significant indicator of the number of transit trips taken for low-income households.
Incorporating Spatial Heterogeneity into Modeling Nonlinear Effects of Built Environment on Intermodal Transit Trips
Enhui Chen, Southeast UniversityShow Abstract
Zhirui Ye (email@example.com), Southeast University
Hao Wu, Southeast University
Understanding intermodal transit trip generation is essential to increase the share of long-distance trips and allocate available resources for the transit system based on anticipated demand. Although many studies have investigated transit trip generation, the existing literature still has limited evidence about the intermodal transit trips and their nonlinear associations with built environment elements over space. This study contributes to the literature by proposing a decision framework to identify the mean relative importance of built environment elements as well as their effective ranges and threshold effects at the spatial scale. An empirical study is conducted using the smart card data in Nanjing, China. The modeling results confirm the existence of spatial heterogeneity and nonlinearity in intermodal transit trips and indicate the proposed hybrid model can significantly enhance the predictive power. The mean relative importance of the distance to the nearest metro station ranks the highest, followed by bus route and land use mix. We then intuitively visualize how intermodal transit trips are nonlinearly associated with built environment elements across different traffic analysis zones (TAZs). Built environment elements tend to have a wider effective range and a larger threshold in TAZs of upper quartile, followed by TAZs of middle quartile. These findings offer valuable implications for planners and developers to formulate targeted policies and create vibrant, livable, sustainable communities.
Transit Accessibility Deficit and Commute Mode Share: Better Driving Accessibility, More Transit Riders
Kristin Carlson, University of Minnesota, Twin CitiesShow Abstract
Eric Lind, Metro Transit, Minneapolis-St. Paul
Access to jobs is a powerful metric for evaluating transportation opportunities, integrating time and distance across the available network. The common currency of the number of jobs reachable in a given time frame from a given location also allows comparison across different modes, such as driving and public transport, recognizing that in most cases access to jobs by driving is greater than by transit. This paper defines transit accessibility deficit as the cumulative number of jobs reachable by driving, less the cumulative number of jobs accessible by taking transit for the same travel duration, and explores how this metric explains differences in the aggregate transit commute mode share in the Minneapolis--Saint Paul, Minnesota metropolitan region. We use a hierarchical probabilistic model to predict transit mode share based on accessibility deficit data and a synthesis variable, transit market area, which captures population density, employment density, vehicle ownership rates, and intersection density. Contrary to our expectations, transit mode share is strongly positively related to transit accessibility deficit, such that the highest transit mode share occurs in the block groups with the largest access deficit relative to driving. This positive association reflects the particulars of the concentric distribution of jobs in the Twin Cities, but suggests commuter mode choice is independent of the overall comparative accessibility offered by driving and public transit.
Examining the Travel Behavior of Transport Disadvantaged Communities using the 2017 National Household Travel Survey
Eronmonsele Esekhaigbe, Wayne State UniversityShow Abstract
Tierra Bills, Wayne State University
Understanding the differences of travel behavior of transport disadvantaged communities, relative to dominant travel patterns is important for supporting transportation investments. Transport disadvantaged groups, including low income, transit dependent, elderly, and disabled travelers tend to be constrained from participating in economic and other activities at their desired levels. The conditions associated with where they live, work, and play; the quality and cost of available modes of transportation, and distinct differences in travel preferences together construct the picture of how these groups are affected by system and policy related transportation investments. This paper is concerned with understanding the nature of travel behavior differences that exists for low income and 0-auto travelers. Using the 2017 National Household Travel Survey, we investigate travel behavior differences at the trip and tour (trip-chain) levels, with emphasis on household structures. Similar to previous studies, we find that disadvantaged groups tend to experience much shorter trip lengths. Further, we find that disadvantaged groups are more likely to engage is multiple tour patterns, although there are more likely to be simple tours with fewer stops per tour and fewer primary destinations.
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