01338293

Component

A new approach for calculating accessibility via both transit and automobiles is presented. Accessibility can be defined as the ability to reach desired goods, services, activities, and destinations. It is an important quantitative transportation performance measure that can be used as one objective measure of livability, a concept which has recently taken on increasing importance. This new approach leverages the parallel growth of open government data and free and open source software to provide a simple, flexible, low-cost method for conducting such analyses. In addition to data provided by the typical transportation planning process, such as traffic analysis zone boundaries and socio-economic data, this approach combines transit schedules published in the standardized General Transit Feed Specification format with map data taken from either Topologically Integrated Geographic Encoding and Referencing (TIGER) files or the OpenStreetMaps Initiative. The tools used for calculating the accessibility measures are built around the OpenTripPlanner software. The outputs of the analyses include opportunity and gravity model accessibility indices, and estimates of the modal accessibility gap by traffic analysis zone. The process can be used to calculate both origin and destination based accessibilities (destination based journey to work trips were used in the proof-of-concept tests). In addition, geographic visualizations including travel time isochrones by mode, accessibility heat maps, and 3D visualizations combining geographic, accessibility, and demographic data were created. This type of analysis has previously been conducted primarily by metropolitan planning organizations or a few academic researchers. This new approach opens the door to much broader use. The approach was first developed and tested using data for the city of Washington, DC, and then for the city of Seattle, WA and some surrounding areas, including ferry routes. This new approach using free and open data and tools opens up accessibility analysis to a much broader array of stakeholders, including technically savvy users in the general public.

01329018

11-0230

English

15p

2011

Transportation Research Board 90th Annual Meeting

DVD

Figures; Maps; References (20) ; Tables (1)

Accessibility; Demographics; Gravity models; Metropolitan planning organizations; Mode choice; Origin and destination; Performance measurement; Public transit; Schedules and scheduling; Traffic analysis zones; Transit operating agencies; Transportation planning; Travel time; Work trips

Open source software

Highways; Planning and Forecasting; Public Transportation; I72: Traffic and Transport Planning

Transportation Research Board Annual Meeting 2011 Paper #11-0230

TRIS, TRB

Feb 17 2011 5:21PM