Traffic Assessment - Renfrewshire Council

Methodology for Residential Development
4.65 The general methodology which has been applied is as follows:
• People Trip Generation – Calculated using information from the TRICS database for residential
related trips.
• Residential Development People Trip Distribution – Distribution will generally follow existing
patterns of Bishopton residents and the wider patterns in Renfrewshire. The existing trip
distribution was obtained through analysis of 2001 census travel to work data. The patterns
arising from above indicate high proportions of residents working within 5km of Bishopton. It is
considered appropriate to continue with this pattern because firstly, there will be a significant
number of new jobs in Bishopton, which will encourage synergy between the land uses and
secondly, the trip generation relates to all trips, not just trips to work and hence a high degree
of non work related trips will occur, for example taking children to school.
• Residential Development People Trip Distribution – The distribution of trips within distance
travelled bands has been undertaken using gravity model principles. For the residential
development this process is based on the number of jobs within ward areas (these are taken
from Annual Business Inquiry (ABI) 2001 (ABI) Statistics)
• Residential Mode Share - The mode share used is that currently occurring in Bishopton again
taken from the 2001 census data of Bishopton. The mode share is applied in bands of
distance travelled to reflect local walking and at the other end of the scale the high proportion
of car trips on longer distances. The impact of the train is also included. However, no
adjustment has been made to account for the likely future upgrading of services on the
Bishopton line (or on the rail network generally) during the implementation phases of the
development which could increase the percentage of travel by train.
Key Information Regarding Residential Development People Trip Distribution
4.66 The 2001 Census identified the distance which people from Bishopton currently travel to work and
the Scottish Household Survey indicated the Council area of workplace. These are indicated in
Table 4.14 and Table 4.15 below.
Table 4.14 Distance Travelled to Work by Bishopton Residents
Distance Travelled 0-5km 5km-10km 10km-20km 20km+
Percentage 20% 32% 41% 7%
Table 4.15 Council Area of Residence and Workplace (1999 - 2002)
Area of Workplace
Area of Residence Glasgow Argyle/Dunbarton Renfrewshire /
Inverclyde
Others Total
Renfrewshire / Inverclyde 28% 3% 62% 7% 100%
4.67 JMP has combined both of the above data sets to determine an appropriate distribution of travel to
work from the proposed development at Bishopton. Table 4.16 indicates the distribution of travel to
work by employment location.