Demand Changes from Metro Line Closures
A Pnevmatikou, M G Karlaftis, National Technical University of Athens, GR
This research focuses on estimating the change of Metro users' usual mode of transport as a result of network disruptions and evaluating the impact of a certain closure on travelers' willingness to pay for alternative modes.
Metro systems are largely considered as the most reliable public transportation systems; however, it is not uncommon for such systems to suffer from occasional service disruptions during regular working hours. These disruptions may be the result of a common signal failure, an accident, a mechanical breakdown, a station renovation, a line closure due to track renovations, or even because of unforeseen emergency situations. Public transport authorities do not generally plan ahead for such contingencies and, as a result, major operational disruptions may be caused in the entire network. In cases of metro line closures, ridership is affected as a result of passenger transfers to alternative modes (buses, private cars, taxis). This change in ridership is mostly reflected by an increase in car usage and consequently in road traffic. However, this behavioral change is not identical over the entire population of travelers. It frequently has only short-term effects, while many travelers report that they do change back to using the Metro once the service is running again (Rubin et al, 2005).
Although this mode shifting due to network disruptions is important both for research and for practice, it has not been thoroughly investigated in the literature, with the exception of Rubin and Brewin who, in 2005, run a follow-up survey of reactions to the bombings in London on July 2005 (Rubin et al, 2005). Because of the vulnerability of Metro networks to disruptions and of the significant interest of these closures to many travelers, our goal in this paper is to investigate three important questions:
1.How is Metro ridership affected during closures?
2.How is road traffic affected from Metro closures?
3.Do travelers return to public transport after the Metro returns to regular operations?
To tackle these three questions, we present an analysis of passenger demand changes that occur because of Metro network disruptions; for this, we use real-world transport (questionnaire) data based on a 5 month partial closure of the Athens Metro network. The analysis was conducted using a Revealed Preference (RP) questionnaire for estimating the change of Metro users' usual mode of transport as a result of the disruption. The survey was conducted using interviews in order to evaluate the impact of a certain closure on travelers' willingness to pay for alternative modes as well as improved services for the existing modes. The research focuses on identifying the criteria that affect travel behavior of Metro users in cases of network disruptions.
A large number of travelers (1600) were interviewed during 2010 and a substantial amount of information was collected regarding daily trip information for the respondents such as origin-destination, purpose and transport mode for each trip segment during the five-month closure of a significant part of the network. The questionnaire also included attitudinal information about respondents such as the reasons for choosing the alternative mode of travel. The objective of the survey was to identify attributes characterizing the modes used by travelers when line closures are in place.
Findings indicate that 24% of rail users during the morning peak did not use the Metro network to continue their journey when a certain part was closed for 5 months, but instead chose some other alternative mode (like car, bus, taxi, tram). From those affected by the closure and those who eventually changed to alternative modes, a 66% transferred to other public transport means and only 20% used their own private vehicle. Further analysis is currently underway to assess the impact of the induced traffic on the road network in cases of an unexpected event that might cause a sudden closure of a fixed track network.
Rubin,G. J., Brewin,C. R.,Greenberg,N., et al (2005) Psychological and behavioural reactions to the bombings in London on 7 July 2005: cross sectional survey of a representative sample of Londoners. BMJ, 331, p606-611.
Association for European Transport