Friday Seminar - Karthik Sivakumaran on Access and the Choice of Transit Technology

MBTA RTS bus 0026

This week's Friday TRANSOC Seminar features Karthik Sivakumaran, Ph.D. candidate, University of California, Berkeley, presenting "Access and the Choice of Transit Technology."

An urban transit system can be made more efficient by improving the access to it.  Efforts in this vein often entail the provision of greater mobility, as when high-speed feeder buses are used to carry commuters to and from trunk-line stations.  Other efforts have focused on the creation of more favorable land-use patterns, as occurs when households within a Transit-Oriented Development (TOD) are tightly clustered around trunk stations.  The efficacy of these mobility and land-use solutions are separately examined in the present work.  To this end, continuum approximation models are used to determine the design parameters that minimize the generalized costs to both the users and the operators of hypothetical transit networks.

Though idealized, these assessments furnish useful and very general insights.  They confirm that if transit is accessed slowly on foot, as is commonly assumed in the literature, then the optimal spacings between routes, and between the stations along those routes, are quite small.  This typically places capital-intensive rail systems at a competitive disadvantage with transit systems that feature buses instead.  However, these spacings expand when access speeds increase.  Hence, we show how Bus Rapid Transit (BRT) and Metro-Rail can become a preferred option for trunk-line service when accessed via faster-moving feeder buses.

By comparison, the influence of altered land use patterns brought by TODs is less dramatic when all users walk to Metro-rail stations.  We find that clustering households around these stations justifies larger spacings between them, but produces only modest reductions in generalized costs.  This is because the larger spacings penalize transit users who reside outside of the TODs.

The seminar will be held at 4:00pm in 534 Davis Hall. Don't forget about Cookie Hour in the library at 3:30! See you here.