Promoting Non-motorised Transport in Asian Cities

Annexes
Annex A: 5 D’s of Transport
The impact of the built environment on transport especially
on non-motorized transport can be understood
from analyzing the impact of variables “D” in landuse.
The first attempt was by Cervero and Kockelman (1997)
who coined original three D’s i.e. density, diversity, and
design. Researchers have expanded this initial – three D’s
and added destination accessibility and distance to transit
(Ewing and Cervero 2001; Ewing et al. 2009) to comprise
the 5 D’s.
1. Density is considered as activity level per unit area.
The activity can be population and employment.
2. Diversity is measured as availability and intensity of
different types of land use.
3. Design refers to the type of local street design in the
neighbourhood.
4. Destination accessibility is measure of the access to
trip attractions.
5. Distance to transit is a measure of public transport
accessibility.
Attribute Impact on Outcome
Density Number of Trips High impact on vehicle trips as more people walk, cycle or use public transport.
Trip Length Research indicates that higher population and employment densities results in closer trip
origins and destinations, on average, and thus in shorter trip lengths, on average.
Trip frequency Little impact. There are chances that reduced trip lengths can increase trip frequencies,
but empirical evidence suggests that the increase is not enough to offset the reduction
in VMT that comes from reduced trip length alone
Mode Share High density makes public transport viable and improves the mode share of non
motorized users
Diversity Number of Trips High impact as diverse built environment constitutes accessibility to different types of
land use which has a high impact on trip-chaining and trip internalization reducing interzonal
motorized trips.
Trip Length High impact as it brings origin and destination very close.
Trip frequency Little impact
Mode Share High Impact on improving non motorized transport
Design Number of Trips High impact on reducing motorized trips as it impacts sidewalk coverage, block size and
accessibility
Trip Length High impact as type of design has an influence on trip lengths. For example, superblocks
have higher trip lengths than traditional urban forms. Shorter block lengths help in
improving NMT trips
Trip frequency Little impact.
Mode Share High impact as it can promote non motorized modes through attractive positioning of
public space.
Destination
accessibility
Distance to
Transit
Number of Trips Little impact
Trip Length High impact as it brings origin and destination very close improving NMT usage
Trip frequency Little impact
Mode Share High impact on improving non motorized transport
Number of Trips Shorter access to public transport improves NMT usage as an ingress and egress modes
Trip Length No major impact
Trip frequency No major impact
Mode Share High impact on public transport and NMT mode share
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