Development of an Urban Accessibility Index

(PI: Chandra Bhat; Co-PIs: Kara Kockelman, Susan Handy, and HMahmassani)

Different urban areas afford their residents, businesses, and visitors different levels of accessibility. The objective of this project is to develop a measure or index of that accessibility which would use information about land development and all available transportation modes. The intent is to develop a formulation for the index that would be acceptable to a) any level of spatial interest (for example, the level of the traffic analysis zone in an urban area or the level of the entire urban metropolitan area); b) any mode-specificity (transit-based index, roadway-based index, rail index, airport access index, or aggregate combinations of modes); c) any purpose- specificity (such as shopping index, social-recreational index, or combinations of purposes; and, d) any time of day specificity (peak periods, off-peak periods, etc.). Such a formulation should provide the flexibility to examine accessibility at any level of detail while also permitting consolidation of disaggregate indices into more aggregate and general indices. The resulting urban accessibility measures can be used to assess/compare transportation facilities within different regions of an urban area or among urban regions and can provide guidance for directing resources for facility improvement in areas with poor transport accessibility.

Keywords: Land-use planning, transportation planning, urban geography.