High Speed Rail, Accessibility and Agglomeration

By collapsing travel times and increasing inter-urban accessibility, high-speed rail (HSR) networks have unparalleled capacity to reconfigure urban economic geography regionally and nationally. How does high speed rail impact urban and regional growth in terms of economic agglomeration, land cover change and population growth? To what extent, may capacity constraints  influence the accessibility contribution by the high speed rail? Using the HSR networks in China and Spain as examples, this project explores the unique properties of high-speed rail and their socioeconomic consequences in urban systems.

Dispersion of Agglomeration through High-speed Rail in China

Despite the eye-catching achievements of China’s high-speed rail (HSR) system in providing fast and convenient transport service, key policy inquires remain unaddressed: Will HSR bring wider economic impacts as expected? If yes, are such impacts generative or distributive, and regionally convergent or divergent? Is China’s transport infrastructure reaching saturation? Our research assesses how HSR has reshaped inter-city accessibility patterns, and how the change in accessibility influenced the productivity, scale and spatial distribution of urban economy. To capture the interaction among cities in an open economy, we expand the concept of agglomeration to include cities’ access to external resources facilitated by regional transport infrastructure, beyond their own endowment. The extensive HSR investment during 2001-2010 not only improved the absolute levels of intercity accessibility for all cities but also narrowed the gaps in accessibility across cities. The panel data models reveal the complexity in the relationship between accessibility and economic performance: there exist both generative components (e.g. labor productivity), and redistributive components to both convergent and divergent directions: the impact on employment is divergent (more toward large cities and particularly in private sectors), while the impact on foreign direct investment is convergent, as Central China becomes a more favorable destination. We do not observe the decreasing return of economic performance to accessibility during the study period. The top-down decision-making structure in China’s HSR system supports the exogeneity assumption of cities’ accessibility with respect to economy, which we verify using instrumental variable models.
HSR is a powerful infrastructure option to improve equality of intercity accessibility at a massive scale and significantly enhance the external agglomeration economies. For project appraisal, it is necessary to extend the standard cost benefit analysis to include the generative benefits; to evaluate the impacts on regional disparities based on distributive effects; and to avoid infrastructure overbuilding through identification of saturation.

Team: Wanli Fang and Jinhua Zhao

Publication: Fang, W and J. Zhao (2014) Dispersion of Agglomeration through High Speed Rail

Capacity Constrained Accessibility of High-Speed Rail

This paper proposes an enhanced measure of accessibility that explicitly considers circumstances in which the capacity of the transport infrastructure is limited. Under these circumstances, passengers may suffer longer waiting times, resulting in the delay or cancellation of trips. Without considering capacity constraints, the standard measure overestimates the accessibility contribution of transport infrastructure. We estimate the expected waiting time and the probability of forgoing trips based on the M/GB/1 type of queuing and discrete-event simulation, and formally incorporate the impacts of capacity constraints into a new measure: Capacity Constrained Accessibility (CCA). To illustrate the differences between CCA and standard measures of accessibility, this paper estimates the accessibility change in the Beijing–Tianjin corridor due to the Beijing–Tianjin Intercity High-Speed Railway (BTIHSR). We simulate and compare the CCA and standard measures in five queuing scenarios with varying demand patterns and service headway assumptions. The results show that 1) under low system loads condition, CCA is compatible with and absorbs the standard measure as a special case; 2) when demand increases and approaches capacity, CCA declines significantly; in two quasi-real scenarios, the standard measure overestimates the accessibility improvement by 14~30% relative to the CCA; and 3) under the scenario with very high demand and an unreliable timetable, the CCA is almost reduced to the pre-BTIHSR level. Because the new CCA measure effectively incorporates the impact of capacity constraints, it is responsive to different arrival rules, service distributions, and system loads, and therefore provides a more realistic representation of accessibility change than the standard measure.

Team: Yu Shen and Jinhua Zhao

Publication: Shen, Yu, and Jinhua Zhao. "Capacity Constrained Accessibility of High-Speed Rail." Transportation (2015).

Hysteresis and Urban Rail: The Effects of Past Urban Rail on Current Residential and Travel Choices

Cities are endowed with and accumulate natural and constructed assets based on their unique histories, which in turn define the choice set of the present. But, common practice is that current behaviour can be described without reference to past circumstances. This work departs from that practice by examining the effects of historical urban rail on current residential location and travel behaviour, from the era of horsecars (1865) and streetcars (1925) to the present in Boston. It uses tract level data to explore the hysteretical effects of past access to rail—the extent to which the urban system retains the impacts of rail even when it no longer exists. Current density and travel behaviour are measurably influenced by past access to rail. These findings are robust to a series of alternate causal, functional, and spatial specifications. The built environment and demographic patterns are found to be the strongest mechanisms for these persistent effects. Past access to rail has shaped the city, and that shape has, in turn, affected travel behaviour. For density and auto ownership there is also a residual measurable effect of past access unexplained by the built environment or demographic patterns. This research shows that past rail access continues to reverberate in current residential location and travel behaviour. These findings of hysteresis add to an understanding of the long-term impacts of rail infrastructure, and suggest that if higher density and lower levels of auto ownership are desirable, policymakers should focus on reuse of areas that were built around rail.

Team: David Block-Schachter and Jinhua Zhao

Publication: Block-Schachter, David, and Jinhua Zhao. "Hysteresis and Urban Rail: The Effects of Past Urban Rail on Current Residential and Travel Choices." European Journal of Transport and Infrastructure Research. 15.1 (2015).

Agglomeration and Diversification: Bi-Level Analysis of 15-Year’s Impacts of Madrid-Seville High-Speed Rail

This paper studies the impacts of Madrid-Seville High-Speed Rail (HSR) on population growth and land cover change in the five HSR connected cities - Madrid, Ciudad Real, Puertollano, Cordoba, and Seville - at both regional and local level. The analysis period ranges from 1991 to 2006. The study finds that, at regional level, the population growth and land development process concentrate mostly towards the two largest cities, Madrid and Seville, while other smaller HSR served cities are also benefited by HSR. At local level, the impacts of HSR are more diverse. The process of population redistribution and land development in each city varies largely. Among all evidences, HSR contributes the most to Ciudad Real, with booming population increases and urban development. In addition, younger people are also attracted to reside in this area. To study the accessibility impacts of HSR on the development of new urban areas in each HSR city, binary probit models incorporating the change of accessibility, population, and neighborhood situations are adopted. The results suggest that, the land development in smaller cities can be majorly ascribed to the improvement of regional accessibility and population growth. However, to explain the urban development process in Madrid and Seville, the inputs with only accessibility and population are not sufficient.

Team: Yu Shen, Jinhua Zhao, João de Abreu e Silva, Luis Miguel Martínez

Publication: Yu Shen, João de Abreu e Silva, and Jinhua Zhao (2015) Agglomeration and Diversification: Bi-Level Analysis of 15-Year’s Impacts of Madrid-Seville High-Speed Rail, Transportation Research Board 94th Annual Meeting Compendium of Papers (No. 15-1885)

Cross-City Comparison: Impacts of High-Speed Rail on Population Growth

This paper studies and compares the impacts of Madrid-Seville High-Speed Rail (HSR) on population growth in the five cities served by this line—Madrid, Ciudad Real, Puertollano, Cordoba, and Seville. The analysis period ranges from 1990 to 2006. The comparative analysis finds that the impacts of HSR largely differ. The association between the opening of HSR and population growth in Ciudad Real is observable; but the relationship is not clear in other station inner buffer areas. To study the impacts of HSR on population growth in each station area, accessibility-based spatial autoregressive models are adopted. The estimates suggest that HSR contributes to Ciudad Real with a relevant population increase, whereas it seldom benefits Puertollano. As the two largest cities along the HSR line, the improvement of accessibility leads to population growth in central Madrid. On the contrary, in Seville, instead of moving towards the central area, with easier access to suburban areas and to other cities, people are likely to move out from the city center. In Cordoba, population growth is not directly influenced by the improved accessibility, but is significantly correlated to the new residential land development, as the urban renovation project affiliated to HSR

Team: Yu Shen, Jinhua Zhao,  João de Abreu e Silva and Luis Miguel Martínez

Publication: Yu Shen, Jinhua Zhao,  João de Abreu e Silva and Luis Miguel Martínez (2016) Cross-City Comparison: Impacts of High-Speed Rail on Population Growth, Transportation Research Board 95th Annual Meeting