Accessibility - what is it and how does it assist economic decision making

Abstract Remit

Walkable communities mean accessible communities: where economic opportunities abound and where access to opportunities is enabled via transportation.  How then are these communities created?  How can better information be provided to decision makers about the benefits of providing improved accessibility?  And how accessible are our existing communities?

Abley Transportation Consultants in conjunction with the New Zealand Transport Agency has developed a methodology for calculating and mapping accessibility including walking accessibility.  The methodology is transferable between countries and is as simple or as complex as required.  It uses a minimum of information such as measured travel behaviour, a network for each transport mode and the location of various land use activities.  For ease of use the methodology has been advanced within a common GIS software platform and a model created to automate common tasks and calculations.  The accessibility model has been used on a number of New Zealand projects including assessing the expansion of a neighbourhood of some 15,000 people and anticipating the expected changes in accessibility over a 35 year horizon.

The model calculates accessibility to a number of important land use activities for different transportation modes including walking.  This enables an accessibility score to be calculated that in turn allows enclaves of poor accessibility to be identified for improvement.  The land use types extend the six core activities proposed by the British Government’s Social Exclusion Unit (SEU 2003) by differentiating between primary and high schools, and including convenience stores.  The eight land use activities are: Doctors, Hospitals, Primary Schools, High Schools, Further Education, Convenience Stores, Supermarkets and Employment.  Once the accessibility of a location is known, it can be targeted for improvement.  Combining this information with geodemographic and economic data provides a very powerful tool to identify at risk user groups.  Accessibility modelling also provides the ability to develop and trial future land use distributions and attempt to optimise use of the existing transportation network.

Steve Abley is the principal author of the New Zealand methodology for calculating accessibility.  Steve’s presentation will describe the process, resources and opportunities for use and development of the tool and how the methodology can be applied.  This presentation will be of interest to local authorities considering regeneration, intensification and growth.  

Author Profile

Steve Abley is the Managing Director of Abley Transportation Consultants.  He has a Bachelor of (Civil) Engineering with Honours Degree from the University of Canterbury and is a Chartered Professional Engineer.  Steve has a strong interest in sustainable transport including walking, cycling and public transport.  Abley Transportation Consultants is often commissioned in these areas and the firm regularly undertakes practical research for furthering practitioner knowledge.  Steve has worked in various countries, is a Professional Member of the Institute of Professional Engineers New Zealand (IPENZ) and a national IPENZ governing board member.