Guidance on Transport Assessment

The National Planning Policy Framework (NPPF) states that 'all developments that generate significant amounts of movement should be required to provide a Travel Plan, and the application should be supported by a Transport Statement or Transport Assessment so that the likely impacts of the proposal can be assessed.' It will then be used to determine whether the impact of the development on transport is acceptable.

The National Planning Policy Framework (NPPF) also states that development should only be prevented or refused on highway grounds if there would be an unacceptable impact on highway safety, or the residual cumulative impacts of the development on the road network are severe.

Following the withdrawal in October 2014 of The Department for Transport Document (March 2007) ‘Guidance on Transport Assessment’ guidance on the preparation of supporting documentation in highway assessment terms can be found in the Planning Practice Guidance (PPG) suite of documents and in particular in “Travel Plans, Transport Assessments and Statements in decision taking”. These guidance documents provide advice on when Transport Assessments and Transport Statements are required and what they should contain and they reiterate the importance of entering into early discussions with the Local Planning Authority and other relevant authorities (Local Transport Authority, Local Highways Authority and National Highways in the case of developments near to or adjacent to the Strategic Road Network) to agree the scale, scope and level of detail required in the assessment prior to its completion and submission as part of a planning application.

Transport Assessments are required for all development proposals that are likely to have a significant impact on the transport network. For developments that are likely to have only a relatively small impact on the transport network, it may be appropriate to provide a Transport Statement instead of a full Transport Assessment and in some circumstances when the transport impact is likely to be negligible then it may not be necessary to provide any formal assessment.

Local Planning Authorities tend to have their own guidelines on what thresholds they consider to be significant and what the level and scope of a Transport Assessment or Statement should include, so it is imperative that early consultations between the developer and the Local Planning Authority are entered into.

Both forms of Transport Assessments should consider the impact of the development on all transport modes, set out proposals to minimise the impact of the development on the transport network and promote measures to encourage sustainable transport. The impact of the remaining development traffic that cannot be reduced further through sustainable transport measures is assessed on the local road network. These assessments take place at the proposed opening year for the development and at a future design year that has been agreed with the Local Authority, which is usually 5-10 years from the date of planning submission, with these future traffic forecasts calculated using TEMPro software and adjusted using site specific data if available.

Local Authorities are generally required to ensure that developments which generate significant movement are located where the need to travel will be minimised and the use of sustainable transport modes can be maximised. A key tool to facilitate this will be a Travel Plan.