Access to the city: Mobility patterns,transport and accessibility in peripheral settlements of Dar es Salaam

This paper is concerned with access to the city for urban residents living in the periphery of Dar es Salaam, Tanzania. The paper presents an analysis of the mobility practices of residents and investigates the mobility constraints they experience in relation to the limited accessibility provided by the urban transport system. The paper draws upon qualitative interviews with residents in the periphery as well as recently collected travel speed data and offers a unique combination of testimony with GIS-based modelling of overall accessibility. A central finding is the overall importance of regular mobility and access to the city for residents in the periphery. Regular mobility is an ingrained part of residents' livelihood strategies. The majority of households rely on one or more members regularly travelling to central parts of the city in relation to their livelihood activities. The analysis reveals a widespread, near-to-universal, dependence on motorized transportation, with the vast majority depending on public transport. Raster-based modelling of overall accessibility provides an indication of the very high travel times endured by residents in the periphery. The analysis identifies and distinguishes between three overall mode types: 1) Private car, 2) public transport and 3) motorcycle/car combined with public transport. While private cars appear marginally faster, differences in travel times are actually limited. This suggests that travel times are less influenced by mode of transport than by road and traffic conditions and highlights how accessibility problems of peripheral settlements are not easily understood separately from the general dysfunctions of the overall mobility system of city.     

Near “real-time” estimation of excess commuting from open-source data: Evidence from China's megacities

Urban commuting has continuously fascinated scholars and decision-makers. As few people live and work in the same place, there is always excess commuting (i.e., the non-optimal or surplus work travel occurring in cities because people do not minimize their journeys to work for most residents). Traditional commuting data sources (e.g., questionnaires and census surveys) are challenged by small samples, high cost, and low spatiotemporal resolution. In contrast, the big social-sensing data (e.g., smart card and mobile phone data) only consider one or two traffic mode of a route, which is not consistent with the real-life condition. This article proposes a framework for modeling excess commuting based on open-source data of the ten most populous megacities in China. We downloaded residential points of interest (POIs) from Lianjia Real Estate website and obtained workplace POIs from China's AMAP, which is widespread used as Google map. The stratified sampling approach was employed to derive commuting pairs. Both commuting distance and time were obtained by the shortest path under public transportation from AMAP. Then, the linear programming method was employed to calculate the theoretical minimum commuting time and distance of each city. We analyzed the statistical property and spatial distributions of excess commuting and found that (1) commuting distances and time (ranging from 9.1 to18.1 km and from 44.8 to 74.3  minutes) of all ten megacities follow a left-skewed normal distribution; (2) in terms of commute cost, all cities show universal core-periphery patterns where the spatial heterogeneity of the commuting time is more significant than that of distance; (3) for each city, the excess commuting measured by time (i.e. from 0.61 to 0.79) is lower than that measured by distance (i.e. 0.68 to 0.89); and (4) the role of mixing land use, waterbody distribution, and centripetal urbanization on urban commuting distance and time is significant.     

Examining the impacts of the Great Recession on the commuting dynamics and jobs-housing balance of public and private sector workers

Research examining commuting-related phenomena remains a key area of geographical research. And although substantial research has attempted to explore the relationships between transportation and land use, little is known about how the impacts of major economic changes such as the Great Recession would affect related commuting dynamics. In addition, commuting studies examining the plight of workers in private versus the public sectors are also virtually non-existent, though the two-groups' commuting dynamics would potentially be affected very differently by the Great Recession. This study contributes to a better understanding of commuting and jobs-housing balance during the Great Recession. We employ metrics from the excess commuting and jobs-housing balance literature in an effort to examine the commuting dynamics of private and public sector workers, with a focus on the time period around the Great Recession. Our analysis is conducted for the Atlanta, GA Metropolitan area. Findings of the study are that private workers experienced better jobs-housing balance over the study period, but they commute longer and more inefficiently when compared with public workers. While the Great Recession worsened both groups' commuting situation, the effect was more significant for public workers in terms of increasing their travel burdens. Since the public sector response to the Great Recession was delayed, policy implications suggest monitoring employment trends during and after economic shocks and recognizing the transportation disadvantages public sector workers may face in future crises. Keywords: excess commuting, jobs-housing balance, the Great Recession, private and public employment, spatial optimization.     

Urban mobility transitions through GDP growth: Policy choices facing cities in developing countries

This paper analyses the factors associated with the private transport modal share in cities of different wealth. We use the 1995 UITP Millennium Cities dataset and smaller samples of matching cities in the 2012 UITP Mobility in Cities dataset. Segmented bivariate analysis using the 1995 data showed that the associations between the private transport share and various socio-economic, transport, and land use variables are mostly non-linear or moderated by third variables. K-means clustering of the same 1995 variables then revealed three distinct groups of cities. Cluster 1 contains cities in developing countries with low private transport share and poor provision for both private and public transport. Cluster 2 contains high-income cities with high private transport share, low population density, and better relative provision and quality of private transport. Cluster 3 also contains high-income cities but with a moderate private transport share, higher population density, and better relative provision and quality of public transport. The evolution of cities from 1995 to 2012 showed that, as cities grow in wealth, they either move from Cluster 1 to Cluster 2 or from Cluster 1 to Cluster 3. Regression analysis provided further confirmation that the private transport share is explained by the variables that define the three clusters. Overall, the paper provides information for cities in developing countries to formulate combinations of transport and land use policies that can contribute to a transition towards sustainable transport systems.     

Inter-regional and inter-temporal analysis of travel behaviour for Asian metropolitan cities: Case studies of Bangkok, Kuala Lumpur, Manila, and Nagoya

The unprecedented demand for travel experienced in Asia, in conjunction with the economic development of the1980s, has resulted in a number of detrimental effects on urban systems. Economic development has certainly intensified per capita income enhancing personal mobility. In Asia, private vehicle ownership and usage have continued to be recognised as an obligatory element of travel for many. Undoubtedly there is a direct relationship between vehicle ownership and public transport usage. Inter-regional and inter-temporal investigations of travel behaviour in Asian cities are therefore necessary to develop an understanding of the future transportation system including suitability and the role of public transport. Since travel data are scarce in Asian countries, inter-regional or inter-temporal travel behaviour investigations do not exist to date. Several travel demand models are developed using discrete choice modelling techniques and Bangkok, Kuala Lumpur, Manila, and Nagoya as case studies. Estimation results of the mode choice models are successfully incorporated to compare travel behaviour trends in selected cities in Asia. The developed models are tested for spatial and temporal transferability.     

Exploring tertiary students' travel mode choices in Auckland: Insights and policy implications

It is crucial that policymakers and public transport operators comprehend tertiary students' travel mode choices and understand the factors that inform these choices in order to manage travel demands effectively and to optimise the use of public transport and improve its quality of service, particularly during the peak hours. This study aims to examine tertiary students' travel mode choices in Auckland, which is recognised as one of the most car-dependent cities in the world. The city is struggling with traffic congestion, particularly around its Central Business District (CBD) during peak hours. Auckland is New Zealand's largest city, with a population of 1.4 million residents. The main campuses of two major public universities, The University of Auckland (UoA) and Auckland University of Technology (AUT), are located in the CBD, attracting a large number of daily trips by both staff and students, particularly during the teaching semesters. However, there is a limited understanding of tertiary students' travel mode choices, particularly the factors that inform these choices when they travel to the universities' city campuses. A mixed methodology approach was used to comprehend the travel mode choices of students attending The University of Auckland and to identify the key factors that are drivers of these choices. The data collection included a questionnaire-based survey, which received 249 responses, and 10 semi-structured interviews with students. Thematic analysis was utilised to codify and then analyse the interviews. Despite the significant car dependency in Auckland, the survey demonstrated that most respondents utilised public transport and active modes when commuting to the university's city campus. Seven factors were identified that inform tertiary students' travel mode choices: cost, parking availability and cost, access to a car, travel time, physical environment, reliability, and attitudinal variables. The interviewees mostly argued that travel cost and lack of or limited access to a private car were the primary drivers of their travel mode choices. The study suggests that different stakeholders, such as Auckland Transport (AT) and The University of Auckland, should work collaboratively to provide an inclusive travel demand management policy. The university could rearrange classes for off-peak hours, and AT could offer tertiary students further discounts during these hours. These actions would result in the optimisation of public transport efficiency, improvement of the quality of the public transport service, and mitigation of traffic congestion around Auckland's Central Business District (CBD).     

Job growth,accessibility, and changing commuting burden of employment centres in Melbourne

How transport and employment agglomeration enhance urban productivity is a fundamental problem for many cities. Internationally, there has been a great deal of interest in the effect of employment concentration on urban productivity, but very few studies have examined its effect on worker commuting burdens and transport costs. This paper aims to advance international knowledge by measuring job growth and costs of labour market access between 2011 and 2016 for employment centres (EC) in Melbourne, Australia. A comprehensive transport cost model is used that incorporates detailed transport costs and travel times associated with transport modes. By tracking job growth and changes in worker commuting burdens, this paper distinguishes ‘high-cost’ ECs from ‘low-cost’ ECs, for their respective labour pools, and identifies which ECs offer opportunities for better transport outcomes. The results show that well-planned public transport (PT) systems and residential development, coupled with walking and cycle networks, are important features of ECs experiencing lower commuting burdens. Drawing upon the conclusions, this research recommends more effective approaches by governments to foster effective investments in urban infrastructure and discusses how broader policy and investment decisions can align to optimise employment agglomeration and minimise negative transport impacts.     

Spatial-modal scenarios of greenhouse gas emissions from commuting in Hong Kong

Transportation is a major source of greenhouse gas emissions in cities. Multiple strategies including green technologies, transport management, urban planning and behavior changes are required to mitigate transport emissions. This paper aims to introduce an analytical framework to investigate the impacts of different spatial-modal strategies on reducing commuting emissions. Based on the optimization approach of excess commuting, the proposed framework incorporates the minimum, maximum and random (unpredictable) travel outcomes to inform planning of an urban form embedded with fewer emissions. This analytical framework is applied to Hong Kong to estimate the emissions ranges (the minimum and maximum amounts) under 42 spatial-modal scenarios - a combination of six spatial strategies (status quo, monocentric, highly polycentric, moderately polycentric, dual-centric and tri-centric) and seven modal strategies (status quo, pro-rail (high), pro-rail (moderate), pro-bus (high), pro-bus (moderate), pro-car (high) and pro-car (moderate)). The findings illustrate the emissions impacts if Hong Kong is further developed following a job concentration or decentralization principle. It also indicates that if Hong Kong is reconstructed to be a city with multiple CBDs, a dual-centric strategy is desirable because both minimum and maximum commuting are shorter than that of a tri-centric strategy. Moreover, the modal strategy to actively promote rail usage shows more impacts on emissions reduction and car usage should be maintained at the current level. If commuter's travl is less predictable, the high rail usage under a dual-centric city form is a more sustainable spatial-modal strategy. The proposed analytical framework of city's commuting emissions affected by structural and modal changes is transferrable to other places and could offer planners different benchmarks of travel pattern to substantiate their sustainable city planning vision.     

Travel and activity time allocation: An empirical comparison between eight cities in Europe

A study of daily time allocation to travel and out-of-home activity is conducted across eight European cities over three countries: France (Lyon, Grenoble, Strasbourg and Rennes), Switzerland (Geneva, Bern and Zurich) and Belgium (Brussels), based on individual travel survey data collected between 1997 and 2006. The effects of socio-demographic, spatial context, transport availability and city-specific variables are investigated thanks to the Cox proportional hazard model. The results indicate that socio-demographic characteristics and city (or country) specific effect play a major role while residential density and proximity to high level road or public transport networks have a very limited impact on time budgets for travel and out-of-home activities.     

Measuring individuals' travel behaviour by use of a GPS-based smartphone application in Dar es Salaam,Tanzania

A range of mega-cities in the Global South have started to invest in Bus Rapid Transit (BRT) systems, as a complement or replacement for informal paratransit services, in an effort to improve the mobility and accessibility in the city. Yet, few studies have tried to analyse the impact of such systems on the mobility patterns of cities' residents, in part because traditional travel diary surveys are often too expensive to conduct and unsuitable to capture spatial mobility patterns in fast growing cities with a high level of informality in spatial development. In this study, we analyse the applicability of a new method of data collection, i.e. a GPS-based smartphone application, to capture individuals travel behaviour in fast growing mega-cities in the Global South. Our case study is the city of Dar es Salaam (DES) in Tanzania, where the first BRT line is currently being implemented. In our study, the GPS-based app was used by individuals in DES to record distances, departure times and destinations of their trips. Socio-demographic data of respondents were recorded in short questionnaires. The spatial distribution of the trip patterns shows the mobility demand in both high and less connected areas. The results reveal a variation in departure times, travel destinations and trip distances that are one the one hand spatially limited within neighbourhoods and away from the planned BRT, and on the other hand along major roads connecting to the Central Business District (CBD). The short average distances of the trips (<3 km) reveal the characteristics of paratransit modes. The GPS-based smartphone application provides an opportunity to policy makers to engage deeply with the spatial reality of local communities, as a basis for transport investments and policy improvements as steps towards an integrated public transport system.     

The Gothenburg congestion charge scheme: A pre–post analysis of commuting behavior and travel satisfaction

The article uses the Gothenburg congestion charge scheme, implemented in 2013, as a case study to analyze the effects and perceptions of a policy instrument directly aimed to change the travel behavior of individuals. For the study, a survey was conducted including measures of commuting habits, attitudes (toward the congestion charge, the environment, automobility, and public transport), and satisfaction with travel, along with socio-demographic and geographical variables. The survey was distributed to a panel of 3500 car owners in the Gothenburg region before the implementation of the scheme, with a follow-up one year later. The analysis use group comparisons and a binary logistic regression analysis and results show that the difference in accessibility of different societal functions using private versus public transport affected the propensity to reduce car travel, whereas socio-demographic variables had a low statistical significance, with the exception of women who were twice as likely to reduce their car travel than men. All studied groups reported a more positive view of the scheme at follow-up, although this effect was more pronounced among those adapting their commuting behavior. In none of the studied groups did the implementation of the congestion charge scheme correlate with any significant change in satisfaction with travel.     

Powered-two-wheelers for city commuting: Insight from Australia's three largest capital cities

The journey to work receives a great deal of research attention due to the peak demand on the transport system. Cities are increasingly concerned with managing traffic congestion and reducing pollution and most of the focus of this research has been on cars, public transport, walking and cycling. In contrast, the role of powered two-wheelers (PTWs), including motorcycles and scooters, in commuting has received little attention, particularly in the context of cities in the developed world. This paper provides new insight into commuting by PTW by drawing on census journey to work data from Australia's three largest cities (Sydney, Melbourne and Brisbane) combined with an intercept survey of PTW commuters in Melbourne. It explores the extent of, and changes in, PTW commuting as well as the demographics of PTW commuters. While PTWs account for only a small percentage of urban commuting in Australian cities, their use is growing rapidly and there is a concentration of commuting by PTW into city centres. PTW commuters tend to be high-income males in skilled professional and technical professions. The implication of these findings for transport policy are discussed.     

The jobs–housing relationship and commuting in Beijing,China: the legacy of Danwei

China’s market-oriented reform has not only revitalized the economy but also changed the physical structure of Chinese cities, which used to be largely determined by the socialist Danwei (or work unit) system. In order to understand the impacts of the reform and the influence of Danwei on jobs–housing relationships and commuting behavior, this study investigates whether there are differences in commuting behavior between individuals who live in houses provided by Danwei and those who reside in houses from private market sources in urban China. We apply the structural equations model to investigate the interactions between housing source (from Danwei or not), jobs–housing relationship, transport mode and commuting time in Beijing, the capital city of China. The results show that Danwei housing commuters have shorter commuting trips and higher usage of non-motorized transport mode than those who live in houses from the market sources. This finding implies that the diminishing influence of the traditional Danwei system and the market-oriented reform in urban development may have changed the jobs–housing balance and increased travel demand in Chinese cities.     

Jobs-housing balance in an era of population decentralization: An analytical framework and a case study

Despite the well-established theoretical understanding on the benefits of compact cities to the attainment of sustainable transport goals, there has been a worldwide trend of population decentralization in cities. In this paper, an analytical framework, which can be applied to other cities to quantify the potential commuting travel savings and environmental benefits of different job policies in cities having different rates and patterns of population decentralization, is presented. A case study of Hong Kong in the 1992-2002 decade is used to illustrate the analytical framework. The findings suggest that a city’s population patterns did have significant implications on the commuting travel savings from alternative job relocation policies. With a dispersed population pattern, the expected environmental benefits from a job decentralization policy can be very substantial.     

The transformation of urban transport in the Czech Republic, 1988–1998

Similar to virtually all formerly socialist countries in Central and Eastern Europe, the Czech Republic has been experiencing a transport revolution since the shift from socialism to capitalism a decade ago. From 1988 to 1998, per-capita car ownership rose by 63% in the country as a whole, and by 93% in the capital city of Prague. Vehicle km of motor vehicle use have more than doubled. Conversely, public transport usage has fallen considerably, by 26% in the country as a whole, and by 19% in Prague. This modal shift from public transport to the private car has resulted from increased incomes, access to Western markets, declining real prices of cars and petrol, removal of restrictions on manufacturing and importing cars, and the car's attraction as a symbol of freedom, affluence, and status. The sharp reduction of subsidies for public transport has forced increases in fares and service cutbacks, which have also encouraged the shift toward the private car. Although the private car is very popular, the sudden surge in car ownership and use has caused significant social and environmental problems: roadway congestion, parking shortages, increased traffic accidents, air pollution, and noise. Given their severe financial limitations, Czech cities are struggling to preserve their public transport systems while accommodating the immensely popular private car.     

Slowly coming out of COVID-19 restrictions in Australia: Implications for working from home and commuting trips by car and public transport

With the onset of COVID-19 restrictions and the slow relaxing of many restrictions, it is imperative that we understand what this means for the performance of the transport network. In going from almost no commuting, except for essential workers, to a slow increase in travel activity with working from home (WFH) continuing to be both popular and preferred, this paper draws on two surveys, one in late March at the height of restrictions and one in late May as restrictions are starting to be partially relaxed, to develop models for WFH and weekly one-way commuting travel by car and public transport. We compare the findings as one way to inform us of the extent to which a sample of Australian residents have responded through changes in WFH and commuting. While it is early days to claim any sense of a new stable pattern of commuting activity, this paper sets the context for ongoing monitoring of adjustments in travel activity and WFH, which can inform changes required in the revision of strategic metropolitan transport models as well as more general perspectives on future transport and land use policy and planning.     

Measuring the structural determinants of urban travel demand

To be best prepared for tomorrow's cities we need to forecast urban travel demand. To this end, this study calibrates an urban travel demand model, which uses the principal structural variables that have been identified in the literature. It uses a robust econometric method, which has been little applied in the sphere of transportation. The results show that two variables stand out from the others: the user cost of transport – by private car and public transport – and urban density. It is surprising, but explicable with the available data, that the demand functions estimated for a given country are independent from the group of countries to which it belongs.     

Managing public transport in developing countries: Stakeholder perspectives in Dar es Salaam and Faisalabad

Most developing country governments face the dilemma of how to promote affordable public transport for the urban poor. In developing countries, the trend of turning to the private sector for the provision of public transport services has resulted in a large number of individual operators whose main aim is (not surprisingly) to maximise profits. The drive for profitability can be achieved by increasing efficiency and cutting bloated costs, but may also lead to unfavourable behaviour that can adversely affect passenger safety and comfort and could also damage the urban environment. The challenge is to find a way to regulate and control this multiplicity of small businesses in such a way as to retain the cost minimisation pressures of the profit-seeking private sector without sacrificing safety, health or quality of service.This paper presents a comparison of stakeholder attitudes to the regulation and control public transport in Dar es Salaam (Tanzania) and Faisalabad (Pakistan). The views of stakeholders were established as part of a wider DFID-sponsored study of ‘Partnerships to improve access and quality of urban public transport for the urban poor’ and were collected using content analysis, literature reviews, historical analysis, case studies, focus group discussions, forums and workshops. The stakeholders involved included users, particularly passengers from low-income households, providers and operators of services (drivers and conductors), and regulatory agencies. The example of the Faisalabad Urban Transport Society (FUTS), effectively a public–private partnership, is described to provide a useful model of regulation and control of private sector operators as well as for reconciling the interests of multiple stakeholders.     

Excess kindergarten travel in Changchun,Northeast China: A measure of residence-kindergarten spatial mismatch

Home-kindergarten travel is an important urban travel activity. This paper firstly discussed the relationship between excess kindergarten travel and residence-kindergarten spatial mismatch. And then questionnaires and GIS are used to provide some baseline analyses of their distribution pattern both statistically and spatially in Changchun. Thirdly, we provide an exploratory analysis of the causes of excess kindergarten travel and spatial mismatch. Results indicate that a) kindergartens in Changchun are highly accessible if children attend their nearest kindergartens, b) however, there is numerous excess travel and high degree of spatial mismatch, nearly 87.1% of the kindergarteners travel excessively, c) the excess travel distances in inner city are much shorter than other areas, and the corresponding spatial mismatch degree is lower. Two critical factors influencing excess kindergarten travel and residence-kindergarten spatial mismatch are summarized. Firstly, the actual causes are a) parents' personal preferences and kindergarten choice tendencies, b) Danwei owned kindergartens generally with higher quality, tendentious enrollment policies, charge threshold, and c) the widespread use of private cars. Secondly, the root causes are limited public expenditure on kindergarten education and its unbalanced allocation, as well as Chinese traditional concept and prevailing way of parenting.