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Dear Sir/Madam DRAFT GUIDE TO TRANSPORT ASSESSMENT IN SCOTLAND I enclose a consultative draft copy of the above Guide. The introduction of the new methodology to Transport Assessment was foreshadowed in NPPG17 Transport and Planning, published in April 1999. Production of the draft Guide follows research which was commissioned and published last year on this subject. You will note that the draft Guide includes a number of significant changes from the research following further consideration of issues raised in the research. The use of the Guide to Transport Assessments is recommended to developers and their transport advisers when preparing TAs for major developments. Planning Authorities are likewise recommended to adopt the principles outlined in the document when considering TAs accompanying planning applications. The Scottish Executive will expect TAs dubmitted for developments affecting trunk roads to have been approved according to the guide. As the Guide is seen very much as a working document, similarly to the STAG appraisal methodology, we would like it to be tested by practitioners over the next year. Consequently, comments on the contents of the draft Guide are sought by 31st December 2003. These can be e-mailed to us at tag@scotland.gsi.gov.uk Alternatively, comments may be posted to Lynn Jameson, Scottish Executive Development Department, Planning Division, 2-H, Victoria Quay, Edinburgh EH6 4SN. Copies of responses will be made available to the public on request. Please indicate if you wish your comments to be treated in confidence. Yours faithfully,
PART 1 - TRANSPORT ASSESSMENT: SCOPE AND PROCESS1. INTRODUCTIONThis Guide sets out the requirements for the preparation of a Transport Assessment. It is in three parts as described below. The Guide is based on research which was carried out for the Scottish Executive by consultants, Steer Davies Gleave during 2001/2. That report, which includes information on case studies is available on the web site : http://www.scotland.gov.uk/planning/ 2.SCOPE AND FORM OF THIS GUIDEFormat of this Guide 2.1 Part 1 describes the Transport Assessment process, its scope and purpose. Transport Assessments are an improvement on previous approaches for understanding the impact of developments upon travel and transport, notably Traffic Impact Assessments (TIAs). 2.2 An outline description of the process of preparing a Transport Assessment is summarised in chapter 5. A Transport Assessment Form is shown at Appendix A. Consideration of the scope of the form and content of a Transport Assessment (the scoping exercise) is particularly important and is discussed in chapter 6. Issues of importance in implementing Transport Assessments are reviewed in chapter 7. The changes required by the need to prepare Transport Assessments will have important implications for developers and local authorities as well as public transport operators and these are described in chapter 8. 2.3 Part 2 sets out how a site should be assessed in a Transport Assessment sense. Chapter 9 describes how the transport aspects of the development site will function and chapter 10 sets out how to assess impacts and devise approaches for minimising them. 2.4 Part 3 describes the Transport Assessment process in more technical detail. This section explains how to assess the travel characteristics of a development giving greater emphasis to public transport, cycling and walking modes. It also explains how travel to the development can be influenced by planning factors such as location, scale, density and layout. 2.5 The appendices provide supplementary information that will be of use to those preparing Transport Assessments and those whose role is to take decisions about planning applications. Appendix A provides a basic Transport Assessment Form while Appendix B comments on the data available for those preparing Transport Assessments for development proposals in Scotland. Mechanisms for Implementation are considered in Appendix C and Appendix D summarises the main differences between the new TA methodology with the old TIA approach. Who Should Read the Guide? 2.6 This Guide aims to assist all those involved in the transport and land-use development process including:
2.7 It will also be of use to those who may need or wish to understand the Transport Assessment process including members of the public who may be affected by proposed developments and groups with specific interests in transport. 3. WHY TRANSPORT ASSESSMENT?Planning and Transport Policy Context 3.1 National Planning Policy Guideline (NPPG) 17 : Transport & Planning sets out an approach to planning development that is sustainable in transport terms. Land use planning can contribute to achieving the Governments broad policy objectives for integrated transport and land use planning through:
3.2 A framework for delivering better integration of transport and land use planning will be a key policy tool. The objective should be to locate key travel generating uses to support more sustainable travel patterns. Such a framework will consist of:
Key Concepts 3.3 Consideration of the transport impacts of a proposed development has to take into account the above objectives. This has several significant implications. Transport Assessment concerns person trips, not car trips. Transport Assessment should build upon and develop the system of Traffic Impact Assessments (TIAs), but be broader in focus and cover access by all modes of transport. A comparison of the Transport Assessment and Traffic Impact Assessment approaches is at Appendix D. 3.4 Transport Assessment focuses on the development site within a catchment area determined by the nature of the development, and assesses accessibility of the site to the catchment by different modes of travel. Dependent on overall Council targets, or agreed targets for the development site, the objective will be to maximise sustainable travel by walking, cycling and public transport, and only then to consider the impact of the residual car traffic. This outcome will be achieved through careful attention to the design and layout of the development to give priority to those on foot, cycling or using public transport ahead of the convenience of car users, and through other measures to improve the infrastructure and services to encourage sustainable travel throughout the catchment area. 4. SCOPE AND PURPOSE OF A TRANSPORT ASSESSMENT4.1 Transport Assessment is a comprehensive and consistent review of all the potential transport impacts of a proposed development or redevelopment. Preparing a Transport Assessment is part of the process of securing planning permission. It should enable decision-makers to understand how the proposed development is likely to function in transport terms. It should set out proposed methods of mitigation designed to reduce adverse transport impacts. 4.2 Transport Assessment should aim to provide supporting evidence to accompany the planning application to demonstrate that the development is sited in a location where current and likely future travel behaviour will produce a desired and predicted transport output. Where developments are proposed in locations that have not been identified as being compliant with land-use planning policy, including Development Plan policy, the developer should demonstrate through the Transport Assessment how the development can support sustainable transport policy. 4.3 A Transport Assessment should enable decisions to be made upon a planning application with the full understanding of the likely transport impacts of a proposed development. The process of preparing a Transport Assessment should highlight ways in which the development can be made more sustainable. In particular, means of reducing the impact of vehicular traffic should be introduced as part of the assessment. By ensuring that such issues are addressed early in the planning process speedier decisions should be possible, since the best possible provision for non-car access will be built into the design rather than added later. 4.4 The Transport Assessment should provide information in a suitable form to enable the local authority and, if necessary, the Scottish Executives Road Network Management and Maintenance Division (RNMMD) to assess and determine the planning application, seek any changes to the proposal and devise necessary planning conditions or negotiate planning or other legal agreements. Of central importance will be a clear summary of the Transport Assessment (the Transport Assessment Form in Appendix A) which can be used by planners, inquiry reporters and councillors to come to an overall view on the suitability of a proposed development/ redevelopment of a specific site. This summary must also enable decision-makers to compare proposals for different locations. 4.5 The preparation and detail of a Transport Assessment will vary depending on the location, scale and nature of the proposed development. The circumstances of each planning application will also influence the level of detail required in the Transport Assessment. The Transport Assessment should be presented in clear language so that lay people can understand the implications. 4.6 Failure to agree a proposed development as a result of deficiencies in a Transport Assessment may result in the need for a revised submission to be made. Scoping discussions that address all potential impacts can reduce the need for revisions to a Transport Assessment. 5. THE TRANSPORT ASSESSMENT PROCESSThe Transport Assessment Process: An Overview 5.1 The basic process of preparing a Transport Assessment can be summarised as shown in Figure 1. Figure 1: the Transport Assessment Process
5.2 The exact detail contained in the Transport Assessment will depend on the scale of the proposed development and the specific circumstances of the case. A Transport Assessment may range from a simple and straightforward process for a small site conforming to the development plan, and reported straightforwardly in a Transport Assessment Form (see Appendix A), to one that depends on full scale four-stage modelling using complex data addressing the transport impacts of alternative modes for a variety of differing types and sizes of development in different locations. No two Transport Assessments are likely to be exactly the same; what is appropriate for one development will not necessarily be satisfactory for another. This in turn creates potential for variation in the detail of the procedure and the final output. Key Elements of the Transport Assessment Process 5.3 A Transport Assessment for a major development or redevelopment proposal (or one with significant transport impacts) should have three main elements:
5.4 The diagram (Figure 2) below outlines the key elements of the Transport Assessment. Figure 2: Key elements of a transport assessment
5.5 For larger developments, or those with significant transport impacts, the process is potentially an iterative one, with refinement of the layout design, improving public transport services and so on, leading to regular discussions between the developer and local authority, and possibly other stakeholders, such as the Scottish Executive. Monitoring 5.6 Many Transport assessments will be submitted with an accompanying Travel Plan that embraces monitoring. Whether or not a Travel Plan is submitted, it will be essential to monitor the performance of the Transport Assessment. This may involve measuring the modal share to assess if targets are being achieved and for parking utilisation. Monitoring is described in more detail in Appendix C. 6. SCOPING THE TRANSPORT ASSESSMENTScoping Discussions 6.1 Developers contemplating a new development or redevelopment should hold discussions with the planning authority as early as possible so as to agree the approach to Transport Assessment. This will enable developers to clarify whether the transport elements of their proposals are likely to be acceptable or whether additional analysis or measures will be required. 6.2 Throughout the process of securing planning permission, the main point of contact for the developer will be with the planning authority. However other bodies (such as the Scottish Executive and public transport operators) may also need to be involved, depending on the nature, scale and location of the proposal. Where a development could have a direct or indirect impact on the flow or safety of traffic on the trunk road, the planning authority must consult the trunk road authority (RNMMD). Initial contact with the planning authority can also identify the need for discussions with other stakeholders. Early discussions with these parties will save time later in the planning process by ensuring that all issues have been covered in the Transport Assessment from the outset. 6.3 There are many instances where development could have proceeded more speedily if the scoping discussions for the Transport Assessment had identified all relevant issues and possible impacts of the proposal. 6.4 Early discussions can assist the developer in ensuring, through the Transport Assessment process, that the proposal complies with the Development Plan in promoting sustainable transport. Subjects for discussion should include:
6.5 The key issue initially is whether the proposed site is in a suitable location and is consistent with policy described in NPPG 17 and in the Development Plan. Development Plans should identify those sites with good accessibility by non-car modes for earlier development as compared to those which can only be accessed by car. The choice of a suitable location for development means that any adverse impacts are more likely to be minimised. 6.6 These discussions should also be used to identify measures needed to promote a wider choice of access to the site particularly by non-car modes, including:
6.7 Wherever possible, planning authorities should avoid continually requesting additional information from a developer when this could have been agreed early in the process. Scoping will also provide the opportunity for developers to enquire as to the availability of local data that may assist in the preparation of a Transport Assessment (see Appendix B). Mode Share Targets (MSTs) 6.8 Transport Assessments are an appropriate vehicle to identify how Mode Share Targets set by individual local authorities for individual developments will be met. The aim is the avoidance, or if necessary mitigation, of the adverse transport impact of development. For Roads Authorities, no-net-detriment is a useful target to aim for in setting MSTs or defining infrastructure improvements, or a combination of these. No-net-detriment means no net increase in travel time or risk of accident as a result of the development. 6.9 Planning authorities may use other criteria, depending on local circumstances. Transport Assessments should identify how the expected mode share compares to the authoritys own MSTs. For a major travel generating development the MSTs should be set on the basis of what is realistically achievable. If the impact of a development proposal on the capacity of a road network requires a modal shift greater than what is realistic to achieve "no-net-detriment", the target would not be met, the road would go over capacity and lead to increased congestion and consequently, travel time. This would point to such a development being refused planning permission. Deciding on the Scope and Form of a Transport Assessment 6.10 A Transport Assessment for a development proposal should present all the transport implications of the proposal. However, the transport impacts of any development proposal are not always easy to predict, and it is necessary for developers to be given the opportunity to explain how the impacts may be different from what might be expected given a brief description of a proposal, and its location. 6.11 There is a balance to be struck between fullness of analysis, and simplicity. A comprehensive approach will provide more useful information for decision-makers but may well be an excessive burden on developers. A simple approach may be easier for developers, but not provide sufficient information for effective decisions to be taken. Where pressure for development is great requesting further details may not be a problem, but where areas are competing for investment opportunities there may well be a tendency for planning authorities to accept TAs which do not cover the full requirements. Criteria for a Transport Assessment 6.12 A Transport Assessment Form (Appendix A) should be completed for all development or redevelopment proposals. However, for domestic and small business applications only, the 4 questions under Travel Characteristics of the TA Form should be filled in to flag up when there is a potential travel impact. The Transport Assessment Form should identify the likely number of trips to be generated and the likely mode share. The planning authority must decide whether a Transport Assessment Form will suffice, or whether more detailed supplementary information is required. 6.13 A Transport Assessment containing more detail will be required where the development or redevelopment is likely to have significant transport implications, no matter the size. The coverage and detail of the Transport Assessment should reflect the scale and the likely extent of transport impacts of the proposed scheme. The planning authority and developer and, in the case of developments that affect trunk roads, RNMMD and their operators, should discuss the content and level of detail of the Transport Assessment required as part of the planning application. 6.14 More detail may be required for those developments that meet any of the following criteria:
6.15 The possible traffic impact of proposed developments is likely to be greatest where any of the following criteria are triggered and so more detailed information should be prepared to supplement a Transport Assessment Form:
TABLE 1: INDICATIVE SIZE CRITERIA ABOVE WHICH SUPPLEMENTARY INFORMATION TO A TRANSPORT ASSESSMENT FORM SHOULD BE REQUIRED
Other considerations: further details to supplement a Transport Assessment Form may be required where the local authority consider the proposals raise significant transport implications, such as where the development is likely to:
6.16 The criteria outlined in Table 1 are intended only as a general guide. Planning authorities may wish to pursue other criteria or require a more detailed approach for particular applications or in particular areas. Such cases may arise, for example, for development proposals in sensitive tourist areas. However, in setting their local criteria, planning authorities should remember that absolute or inflexible thresholds might encourage developers to try and submit planning applications for schemes that fall just below the threshold in order to avoid preparing a detailed Transport Assessment. 6.17 Another potential concern is that developers may submit planning applications on an incremental basis for parts of a site in order to avoid the requirement to prepare a detailed Transport Assessment for the whole site. This is most likely to arise in the case of housing development. Where this pattern of development will have a cumulative impact on the trunk road, RNMMD will require a full TA which covers the development as a whole. 6.18 Furthermore, local authorities must recognise that the importance or relevance of impacts is not related solely to size. Although as a general rule the larger the proposed development the more information will be required, there will be exceptions whereby relatively small developments have potentially very serious impacts. For mixed-use development, it will probably be best to discuss the requirements for a Transport Assessment for each separate proposal rather than devising general criteria, as each scheme is likely to be different. Implementing a requirement for a Transport Assessment (whether it be a simple form or a detailed Transport Assessment) to be prepared for all development and redevelopment will help to avoid such difficulties. 6.19 The criteria outlined above may also refer to developments where there may be changes of use or alterations or intensification of an existing use. However, where there is likely to be no change in the amount of vehicle or people movements, a simple Transport Assessment Form may suffice. Nevertheless the proposed development must be analysed to assess whether significant additional traffic will be generated. In cases where planning permission is not required a Transport Assessment cannot be stipulated. 6.20 For policy compliant proposals i.e. those in accordance with an up to date Development Plan, the level of detail required for Transport Assessment may be reduced. Other Purposes of Scoping Discussions 6.21 In addition to defining the scope of the Transport Assessment, discussions between a developer and a local authority should highlight, at the earliest possible stage, any additional requirements or changes that may be needed to the layout and design of the proposed development. These might include infrastructure changes to make access on foot or cycle easier, required improvements to public transport services, whether a Travel Plan needs to be submitted, and the likely content of a Section 75 agreement. On-going liaison between developers and the local authority will enable agreement as to the nature and scale of the development so that later, and generally more expensive, changes will not be needed. 6.22 While a key aim of a Transport Assessment is to promote access by sustainable modes and to reduce car dependency, there will in many cases still be highway and traffic impacts to address and deal with as part of the planning application. However, it is particularly important to ensure that all the ways to promote sustainable modes and reduce car-use have been fully explored and utilised. Other traffic management measures should also be considered before looking to increase highway capacity. 7. IMPLEMENTING TRANSPORT ASSESSMENTSChange of Use 7.1 Even where the initial occupier is known, some land uses such as offices, could change over time. For example, an office used as a telephone call centre could change into a training centre for the same occupier but with significantly different transport consequences. 7.2 As a change of use could easily result in different travel characteristics a Transport Assessment (or a Transport Assessment Form) should be requested where the change is likely to result in a material change in trips. Unless a site has been cleared (in which case any proposal is more likely to be for a new development anyway) the change of use is from the previous or original use (in planning terms) rather than the current vacant status of a building or site so the baseline should be that of the original use or activity on the site. Transport Assessments accompany planning applications and will only be required for those changes of use that require planning permission. Speculative Development 7.3 Speculative development raises a particular issue: it may be unclear who the eventual occupier of a development will be. While some developments may only be useable for one purpose, others, such as industrial units or offices, could be used with radically different intensities with differing transport impacts. 7.4 Speculative development and outline planning applications pose difficulties since the ultimate occupier or some details of the scheme will not be identified as part of the application. Such proposals must be handled carefully to ensure that the benefits of the Transport Assessment process are not lost. Relevant points to note are:
7.5 It may be appropriate to confine the Transport Assessment only to infrastructure matters that can be provided by the developer and require a Travel Plan to encourage behavioural change from the occupier. The developer would be required to take on responsibility for the Travel Plan prior to passing it to the occupier. Several Small Developments in Close Proximity 7.6 With several small proposals in close proximity, a more detailed Transport Assessment for the group may be appropriate than might be considered necessary for each proposal in isolation. If a planning authority wishes to promote several small developments near each other, they should aim to assess the major transport issues arising from the entire scheme, ideally at the time the site or area is being designated in the Development Plan. 7.7 Conversely, where proposals may emerge independently from one another, rather than as a single proposal, the situation is more complex. This can occur in a domino effect when one successful application leads to further proposals, as may occur with housing. Planning authorities may be able to foresee when this is likely to occur (or react when it starts to happen), by aiming to assess the sites together, possibly as part of an area-wide development brief or master plan. Freight 7.8 Most developments will require service access for freight or delivery vehicles. In addition there will be some activities that are major generators of freight movements. The efficiency of freight movements and deliveries can be improved by:
7.9 Transport Assessments should be required for major freight generating developments. 7.10 Local authorities can promote sustainable distribution patterns by:
8. THE ROLE OF STAKEHOLDERSRole of Developers 8.1 Developers, and their agents, are primary responsible for producing the Transport Assessment for a development or redevelopment proposal, subject to role of local authorities and others, as outlined later in this chapter. Each new development, or redevelopment proposal, will require a Transport Assessment to be submitted alongside the planning application. The Transport Assessment will comprise a Transport Assessment Form plus any supporting material as required. 8.2 Developers should liaise with the planning authority at an early stage of planning the development in order to ensure that the type and scale of the proposal is suitable for the site under consideration. They must also liaise with transport authorities, including the Scottish Executive (in the case of Trunk Roads), and public transport operators to demonstrate how the development will function in transport terms and to identify any possible adverse transport impacts. This process of consultation is likely to save time and costs so the planning application should progress more speedily. 8.3 Detailed design of the proposed development should take account of the policy requirements set out in NPPG17. Developers will need to discuss provision for improved public transport services to the site at an early stage. In preparing a Transport Assessment developers, or their agents, will need to undertake different types of analysis to that for a TIA and to present different types of information. 8.4 Developers who ensure that new development is located, designed and implemented so as to promote access by sustainable modes of travel (walking, cycling and public transport) will benefit in a number of ways. As NPPG 17 makes clear, such development has an increased likelihood of gaining planning permission without undue delay. It also ensures that development maintains high levels of accessibility to customers, workers and visitors, whatever the transport circumstances. In addition, development which is well integrated with other facilities and services, is likely to prove more popular as a place to work in and visit. Furthermore, reduced dependence on car access will enable savings on site and construction costs for parking, as well as freeing up potentially valuable land for development use. It is therefore not surprising that many developers see the economic benefits to be gained from ensuring that new development is highly accessible by several modes of transport and not only the private car. Role of the Local Authority 8.5 Scottish local authorities are both the transport authority and the planning authority, except in respect of passenger transport within the area of responsibility of Strathclyde Passenger Transport. The Scottish Executive has overall responsibility for the trunk road network, and planning authorities are required to consult the Scottish Executive in all cases where a proposed development is likely to have an effect on the flow or safety of traffic on the trunk road. 8.6 Local authorities have a key role in the Transport Assessment process in their functions relating to land-use planning, highways and transport. They should:
8.7 Local authorities should be involved in assessing the transport and travel characteristics of all development and redevelopment proposals. They should help to assess how major proposals support the targets and objectives within the Transport Strategy. 8.8 Local authorities will also be involved in developing transportation measures to support major development proposals, such as traffic management and on-street parking, or providing new infrastructure. At the strategic level, local authorities should also be involved in assessing the accessibility of locations in Development Plans, which will also be important in preparing Transport Strategies. Role of Public Transport Operators 8.9 Developers are advised to discuss public transport provision to the site, first with the local authority and Strathclyde Passenger Transport where appropriate, and then with public transport operators such as local bus companies, Train Operating Companies and the Strategic Rail Authority. Local authorities are well placed to assist in discussions with these organisations. 8.10 Public transport operators will need to consider what alterations may be needed to existing services or what infrastructure provision must be made for new services to ensure access to the development. They may also be able to advise and comment on the layout and design of development. 1. Planning for Mode Share in New Development (Scottish Executive, 2001)
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