MODELLING OF VEHICLE-KILOMETRES OF TRAVEL BY CAR FOR THE JOURNEY TO WORK IN SYDNEY, AUSTRALIA
Abstract: In low
density, car-dependent cities
such as Sydney
there have been
two drivers of increased
VKT: increasing use
of the car
for the journey-to-work; andincreasing
spatial separation of
homes and workplaces.
Descriptive analyses of
data from the Census
of Population and
Housing, Journey-to-Work Tabulations
by local government area
(LGA), show how
person-kilometres of travel
by outer suburban residents (greater
than 20km for
the Sydney CBD)
has mushroomed from
1961 to 1996, and how VKT by car
has also exploded in the same suburbs (from 1981 when modal data were first
reported).
The paper describes
a modelling framework
that allows future
VKT by car
for the journey to
work from LGAs
in Sydney to
be estimated as
a function of future urban form and
socio-economic
characteristics at the
LGA level. Cross
sectional and inter-census change
statistical models of LGA travel
behaviour and urban
form (such as, accessibility to
employment, density) are
fitted. Spatial modelling
(the intervening opportunity model)
represents the third
approach and the
LGA preference function (for longer or shorter job
destinations) is evaluated across LGAs and through time. A statistical model
relates the slope of the preference function (and hence the LGA trip length frequency
distribution) to urban
form. Nine different
scenarios of urban
form have been formulated for the year 2011 to test a range of
assumptions - existing trends and
centralisation / decentralisation of
homes and workplaces –
and the practical application of
the models are
demonstrated to evaluate
progress towards sustainable transport targets.
Author: Putu Alit Suthanaya
Journal Code: jptsipilgg060003
