Overview: Comparison of Transport Assessment and Traffic Impact Assessment
The key difference is that Transport Assessments cover all modes of transport from a person-trip perspective, with the emphasis on walking, cycling and public transport whereas Traffic Impact Assessments generally concentrated on accommodating car trips (to ensure that the traffic impacts associated with a new development would be accommodated) and gave only limited attention to accessibility by non-car modes.
Table 2.1 below summarises the main differences.
Table 2.1: Transport Assessment and Traffic Impact Assessment Compared
|Traffic Impact Assessment||Transport Assessment|
|Modes considered||Focus on car but others may be included||All modes considered but initial emphasis on walk, cycle and public transport.|
|Transport implications covered||Comparison to similar developments||Accessibility and mode split analysis.|
|Impacts considered||Road safety and traffic||Accessibility of site by all modes of transport.
Traffic and highway impacts
Rail, water and air transport
|How are negative impacts addressed?||Increase road capacity and add safety features.||Comprehensive assessment of access by all travel modes leading to additional walking, cycling and public transport infrastructure and service improvements.
Additional road capacity and safety features.
Developers now need to consider a wider range of options to deal with the transport impacts of a development rather than simply increasing highway capacity to meet forecast demand.
Such measures may include the preparation of a Travel Plan, financial incentives to encourage alternatives to private car use, infrastructure improvements to make walking and cycling more attractive or public transport service improvements. Some aspects of the Traffic Impact Assessment approach are still relevant to Transport Assessment since most new developments will result in increased traffic in the immediate locality. Issues relating to parking provision, road safety, junction and link capacity must therefore still be considered within a Transport Assessment