68
N. Akhtar and P. N. Kuriakose
in Indian National Rupees (INR) terms (using the current exchange rate of USD 1
to INR 74.93).
3.3.3 Public Transport Accessibility Level (PTAL)
In order to analyze the present public transit infrastructure of BBMP, a Public Transport Accessibility Level (PTAL) map was drawn by measuring the Accessibility
Index (AI). The AI is calculated by utilizing the walking distance from Point of
Interest (PoI) and Service Access Points (SAP), peak hour frequency of transits (busbased and rail-based), walk speed, and reliability factor. The procedure followed is
the same as that of London PTAL [36], with changes in walking speed and reliability
factor as per Surat PTAL methodology [1].
• Point of Interests (PoI): In London PTAL methodology, PoIs were considered to
build development. However, due to lack of availability of building footprint data,
the study area was divided into grids of 500 × 500 km
2 and their centroids taken
as PoIs.
• Service Access Points (SAPs): These are the transit stops like bus stops and metro
stations. 2,673 bus stops and 24 metro stations were mapped in the study area.
• Walking speed: The London methodology followed walk speed of 4.8 kmph.
However, as per the Indian NMT infra conditions Surat PTAL considered a walk
speed of 3.6 kmph and the same was adopted for this study.
• Reliability factor (k): Reliability factor is taken to account for the various unaccounted delays, which may be occurring at the ground level. Following the mixed
traffic conditions prevailing in our country, since Surat PTAL methodology considered k = 0.75 for Metrorail and k = 2.5 for buses (non-BRTS), the same was
adopted for this study.
• Public transit frequency: The frequency of metro and buses are as per the primary
survey conducted.
The PTAL map was formed after calculating AI as per the following steps:
• The whole BBMP area was divided into 3,318 grids of 500 × 500 m
2 and each
of their centroids were marked as PoI
• The shortest walking distance was calculated from these PoI to the SAPs (bus
stops and metro stations)
• The Waiting time (WT) is calculated by dividing the walking distance by the
walking speed, considered to be 3.6 kmph
• The average waiting time (minutes) is calculated by the following formula.
AWT = ( 0.5 ∗ (60/frequency) ) + k
(3.1)
Now the Waiting time (WT) and Average Waiting time (AWT) are added to find
the Total Access Time (TAT) in minutes.
N. Akhtar and P. N. Kuriakose
in Indian National Rupees (INR) terms (using the current exchange rate of USD 1
to INR 74.93).
3.3.3 Public Transport Accessibility Level (PTAL)
In order to analyze the present public transit infrastructure of BBMP, a Public Transport Accessibility Level (PTAL) map was drawn by measuring the Accessibility
Index (AI). The AI is calculated by utilizing the walking distance from Point of
Interest (PoI) and Service Access Points (SAP), peak hour frequency of transits (busbased and rail-based), walk speed, and reliability factor. The procedure followed is
the same as that of London PTAL [36], with changes in walking speed and reliability
factor as per Surat PTAL methodology [1].
• Point of Interests (PoI): In London PTAL methodology, PoIs were considered to
build development. However, due to lack of availability of building footprint data,
the study area was divided into grids of 500 × 500 km
2 and their centroids taken
as PoIs.
• Service Access Points (SAPs): These are the transit stops like bus stops and metro
stations. 2,673 bus stops and 24 metro stations were mapped in the study area.
• Walking speed: The London methodology followed walk speed of 4.8 kmph.
However, as per the Indian NMT infra conditions Surat PTAL considered a walk
speed of 3.6 kmph and the same was adopted for this study.
• Reliability factor (k): Reliability factor is taken to account for the various unaccounted delays, which may be occurring at the ground level. Following the mixed
traffic conditions prevailing in our country, since Surat PTAL methodology considered k = 0.75 for Metrorail and k = 2.5 for buses (non-BRTS), the same was
adopted for this study.
• Public transit frequency: The frequency of metro and buses are as per the primary
survey conducted.
The PTAL map was formed after calculating AI as per the following steps:
• The whole BBMP area was divided into 3,318 grids of 500 × 500 m
2 and each
of their centroids were marked as PoI
• The shortest walking distance was calculated from these PoI to the SAPs (bus
stops and metro stations)
• The Waiting time (WT) is calculated by dividing the walking distance by the
walking speed, considered to be 3.6 kmph
• The average waiting time (minutes) is calculated by the following formula.
AWT = ( 0.5 ∗ (60/frequency) ) + k
(3.1)
Now the Waiting time (WT) and Average Waiting time (AWT) are added to find
the Total Access Time (TAT) in minutes.