Aylesbury transport model

A transport model based on information collected in 1992 and 1994 has supported the development of both land use and transport strategy in Aylesbury for the last ten years. It has not only added to the credibility of the District Local Plan, but has also made a major contribution to the success of funding bids for major transport projects.

Since the information for that model was collected, there have been a number of changes across the town, including the Fairford Leys development, Aston Clinton bypass, changes to household structures and working patterns, and an increase in car ownership. These changes, combined with Government guidance and Aylesbury's status as part of a Government designated growth area, made it necessary to construct a new transport model.

Building the new transport model

The development of a new transport model was made possible thanks to substantial financial contributions from the Government's Growth Areas Fund (GAF). This has enabled the authorities to create a model that will achieve regional as well as local coverage, so that in the future it can be used to support infrastructure assessments across Buckinghamshire, as well as informing decisions on future development allocations and transport projects in Aylesbury.

The new transport model makes extensive use of information from the 2001 Census, data collected in a comprehensive programme of roadside and household surveys (carried out in May 2005), and information from:

• Bus and train passenger surveys
• Traffic counts
• Journey time surveys

Key findings

Household size

• Proportion of households containing only one person increased from 22% to 26%
• Average number of persons per household has fallen from 2.55 to 2.53
• Household size varies from 2.09 in Central ward up to 2.81 in Quarrendon ward
• Coldharbour Ward has second lowest average of persons per household (2.35)

NB -  2/3 of new households are in the Coldharbour Ward (900 new houses)

Employment

• Number of employed people per household has increased from 1.32 to 1.39
• Coldharbour Ward has highest average of employed people per household (1.43)

Travel

• Proportion of households without access to a car fallen from 25% to 19%
• Proportion of households with access to 2+ cars increased from 28% to 35%
• On average households make about 8 single journeys per weekday
• 51% of journeys are people travelling as car drivers & 15% as car passengers
• As the main mode of travel:
  -   Walking accounts for 22% of all journeys
  -   Bus accounts for 3% of all journeys
  -   Rail and bicycle for 2% each
  -   Taxi and motorcycle around 1% each
• Average journey lengths vary - 1.1km (walk) up to 37.4km (rail)
• Average journey length as a car driver is 9.9km

Traffic movements

• Through traffic accounts for just 10.9% of all traffic movement in Aylesbury
• Traffic flows across Aylesbury have increased by 19% since 1992 (1.3% a year)
• Journeys wholly within Aylesbury have increased by 28% (1.9% a year)
• Through traffic has increased by 17% (1.2% a year)
• A41 Aston Clinton Road has highest number of through trips (c. 8500 in 12 hrs)
• Traffic entering Aylesbury in the morning peak period has fallen
• Traffic entering Aylesbury in the evening peak period has risen

NB -  These last two findings are consistent with Census results that show an increase in net out-commuting levels