TAG Unit 3.3.8: The Townscape Sub-Objective

December 2004

1. The Townscape Sub-objective
1.1 Introduction
1.2 Methodology for Plans
Overall Impact Scoring
Qualitative Comment on the Effects of an Option
1.3 Methodology for Strategies
2 Application of TAG to Highway Schemes
2.1 Methods and Worksheets
2.2 Data Transformation from DMRB to TAG
2.3 DMRB Stages 1 and 2/ TAG
3 Further Information
4 Document Provenance

1. The Townscape Sub-objective

1.1 Introduction

1.1.1 The reader should be aware that it is helpful to read this TAG Unit in conjunction with The Environmental Capital Approach (TAG Unit 3.3.6). Townscape is the physical and social characteristics of the built and unbuilt urban environment and the way in which we perceive those characteristics. It is this mix of characteristics and perceptions that make up and contribute to townscape character and give a 'sense of place' or identity.

1.1.2 The physical characteristics of a townscape are expressed by the development form of buildings, structures and spaces. The development form influences the pattern of uses, activity and movement in a place and the experience of those who visit, work and live there.

1.1.3 The social characteristics of a townscape are determined by how the physical characteristics (i.e. buildings, structures and open spaces) are used and managed. For example, the character and value of a pedestrianised square in a town or city centre is very different to a square that has not been pedestrianised.

1.1.4 It is sometimes difficult to distinguish the boundaries between townscape and landscape and between townscape and heritage. It is often the success of the interaction between all three that determines how well a place works. The impacts of a transport proposal on all three (landscape, townscape and heritage) should therefore be appraised, recognising the interplay where appropriate.

1.1.5 On the issue of the boundaries between townscape and landscape, the extent to which impacts are appraised under any one of these sub-objectives will depend on the context of the proposal. The approach for townscape does not specify a minimum settlement size to which it should be applied and will depend on the nature of the proposal in question. For example, a junction improvement in a village may well result in townscape impacts

1.1.6 Townscape differs from heritage, in that it encapsulates all aspects of the urban form and not just those of an historic nature. Undistinguished modern buildings, for example, with arguably little in the way of current architectural or historic character and value, may still be important in contributing to the distinctive nature of an urban area. For example, the high rise office blocks and modern apartments in London's Docklands give that area a distinctive character and value. However the underlying archaeological and historic framework may partly define and be reflected in the grain of a townscape.

1.1.7 This approach for appraising townscape is analogous to the environmental capital methodology used for landscape. It builds on the townscape assessment methodology in DMRB 11.3.5.8 and incorporates the principles of good practice urban design. This guidance has been developed by DfT. Plans are in progress to trial the approach in order to test its robustness.

1.2 Methodology for Plans

1.2.1 The methodology for appraising the impact of plans on townscape has the following four stage approach:

• to describe sequentially the characteristic features of the townscape;
• to appraise townscape capital - using a set of indicators, this is done by assessing
  • the importance of these characteristic features,
  • why and who they are important to, and
  • their relationships in overall townscape forms and patterns.
• to describe how proposals impact on the townscape features, including effects on its distinctive quality and substantial local diversity; and
• to produce an overall assessment score on a seven point scale.

1.2.2 The approach set out below enables transport planners, town planners, architects and the community at large to identify methodically townscape elements (character) and values (capital) affected by the proposal, and the role played by urban design and mitigation. Given that 'townscape' is a complex mix of physical features and patterns, and cultural understandings, the level of detail to which townscape assessment and appraisal is undertaken depends very much on the purpose of the exercise and the type of townscape in question.

1.2.3 Stage 1: Describe urban character. The first stage starts by describing the urban character. This process is a means of systematically recording and expressing the characteristic and locally distinctive features of an area. The process identifies and describes what currently exists in the townscape and any discernible trends which would lead to degradation or loss of those characteristic features in the absence of the proposals. Use can be made of documents which describe an area, such as townscape appraisals, Conservation Area character appraisals, descriptions of listed buildings and Local Plan policies. This will provide a baseline character against which the incremental impact of proposals on that character can be appraised. The process of describing urban character does not itself make a quality judgement. Quality judgements (that is, appraising the importance of features contributing to local character) are made in the subsequent 'capital' stage of the appraisal.

1.2.4 Stage 2: Appraise townscape capital. The second stage, analogous to the concept of environmental capital, appraises what matters in the townscape and why it is important. For example, certain buildings and open spaces may have been constructed to commemorate an event or person and may have a special significance for local people. In a densely built up area, an attractive open space may be important because it functions as an essential 'safety valve' in relieving the stress of urban living. As with the process for describing urban character, it is important to assess what matters and why at present and how that may change over time in the absence of the proposal. This provides a base level of environmental capital against which the impact of the proposal on that level of capital can be appraised. Environmental capital is a suitable methodology to use because it builds on information about urban character by using a set of common criteria and definitions to add cultural and subjective values and assess impacts, in order to produce an overall qualitative summary assessment on a seven point scale.

1.2.5 Stage 3: Appraise the proposal's impact. This stage of the approach involves describing and scoring the impact of the study proposal on each of the townscape features/attributes, taking account of the baseline environmental capital established in the preceding stages. The descriptions and scores produced in this stage will inform judgement about the overall assessment score.

1.2.6 Stage 4: Overall assessment score. This stage consists of deriving an overall assessment score (on the standard seven point textual scale: large/moderate/slight beneficial and adverse, neutral). It will be informed by the descriptive comments and scores for the impact described in Stage 3 and the definitions given below for the scores.

1.2.7 Using these four stages it is possible to consider how well, or not, a proposal can, in the first place, fit into and enhance the townscape, and in the second place be mitigated to retain, improve and protect characteristic features and townscape patterns. The inter-relationships between the historic characteristics of the townscape must be cross-referenced by considering the character of the townscape being appraised and its historic features. They will not, however, be dealt with in any detail in this guidance on townscape appraisal to avoid double-counting.

1.2.8 The process has been designed to enable the townscape impacts of an investment proposal to be appraised both in the presence or absence of an Environmental Statement. This means that where such a Statement exists the townscape assessment worksheet (Worksheet 1 provided at the end of the unit) will act as an easy reference summary. Where no statement exists the worksheet can still be used, drawing on various sources of existing information to complete the appraisal. The results should be easily understood and will enable any ensuing discussion over specific proposals to focus on the relevant issues. Where there is no Environmental Statement and little townscape assessment reference material to draw on, no more than a cursory scheme appraisal can be made.

1.2.9 Features, for the purposes of this guidance, are the summation of those attributes which most strongly define a townscape and which exhibit the impacts of an infrastructure project. In order to accurately assess the character of a townscape it is important to identify and describe the characteristic elements of the townscape under the most relevant "feature" heading in Worksheet 1. This will set the context for appraising the impact of scheme proposals. The Environmental Statement for the scheme (if one exists), should have classified the townscape and set the wider context through reference to localised townscape assessments. This approach has been taken to make appraisal of the impacts of individual scheme proposals as concise and straightforward as possible. It should also provide a consistent basis for comparison of impacts between schemes. Definitions of the features which combine to define townscape are given below. Features are a mixture of physical (development form) and cultural characteristics and the way in which people perceive these characteristics.

1.2.10 Layout is the way that buildings, routes and open spaces are placed in relation to each other. It provides the two dimensional arrangement on which all other aspects of the form and uses of a townscape depend. It is influenced by the structure of the townscape (the connecting framework and hierarchy of routes and spaces) and by the urban grain. This is the pattern of the arrangement and area of buildings and their plots in a settlement and the degree to which an area's pattern of streets and junctions are small and frequent (fine grain) or large and infrequent (coarse grain). For example: "this townscape is characterised by residential streets interspersed with small urban parks".

1.2.11 Density and mix refers to the amount of floorspace of buildings relative to an area and the range of uses. Density determines the intensity of development and with mix contributes to the vitality and viability of a townscape. For example, a transport proposal may encourage the preponderance of certain building uses within an area.

1.2.12 Scale is the size of buildings and structures in the townscape in relation to their surroundings. It can be understood in terms of the height and mass of buildings and structures. Height determines the relationship between buildings, structures and spaces and the visual impact on views, vistas and skylines. For example, the construction of a road flyover or rail viaduct may have a major impact on views and vistas and skylines.

1.2.13 Appearance and local distinctiveness of buildings and structures within a townscape are influenced by their detail and materials. Detail refers to the craftsmanship, building techniques, facade treatment, styles and lighting. Materials refers to the texture, colour, pattern and durability and how they are used. It is important to appraise how well, or poorly, transport plans fit in with the appearance of buildings and structures.

1.2.14 Human interaction - this term relates to the way people - rather than vehicles - interact with the urban environment. A major element in this relationship is how the community works in terms of interactions in those places that together contribute to townscape. It is important to appraise how social interactions and their relationship with townscape may be changed by the implementation of a transport proposal. In an urban environment communities are omnipresent. However the centres of those communities (e.g. main shopping areas) may be more highly valued. One indicator of whether a strong community exists will often be the presence and scale of pedestrian activity (particularly in the centres of communities), together with the quality of the pedestrian environment (excluding any noise or air quality factors, covered elsewhere). One can imagine an environment where, for example, high levels of pedestrian activity on narrow pavements are in close proximity to heavy vehicle flows. This attribute should also take account of more static interactions between townscape and people, such as the presence of shops, pavement cafes, and seating.

1.2.15 Cultural - this term should cover descriptions of how townscape elements of a traditional or historic nature contribute to townscape character. For example, built forms and architectural styles, the presence of coherent groups of buildings or distinctive street patterns, and notable and cherished buildings and other cherished features. Description of such townscape features must be viewed in terms of their contribution to the overall townscape character, rather than in terms of their heritage value, which will be separately appraised in more detail under the Heritage of Historic Resources sub-objective.

1.2.16 Summary of character - this should summarise and pull together the relationship between the primary characteristics and features or attributes of the townscape being appraised. More general observations on the texture and diversity of the townscape, its scenic qualities, type and degree of development and visual unity or disharmony should be made here.

1.2.17 Townscape indicators are the criteria along the top of Worksheet 1, from left to right, against which to assess the descriptions for each of the features. They should read in sequence, from left to right, to make impact appraisal on each feature straightforward. Each feature or attribute should be assessed using the full sequence of indicators to enable a meaningful and accurate impact appraisal to be made. Definitions for each of the townscape indicators are given below, together with advice on describing impacts and what would constitute additional mitigation. In making these assessments you will need to take account of how features may change over time in the absence of the proposal.

1.2.18 Description - This should describe the existing townscape, before the scheme is constructed.

1.2.19 Geographical scale - This is about the geographical scale at which the feature/attribute matters to both policy makers at all levels and to the local stakeholders (businesses, interest groups, residents, and so on). The scale at which characteristics, described against each feature, matter will not necessarily be on the same scale as the attribute itself. For example, a large urban park may only matter to local people, while conversely a small single element in the townscape, for example, the new Sainsbury Wing of the National Gallery, will matter at a national scale for a number of reasons.

1.2.20 Rarity - should be interpreted as to whether the townscape features/attributes being evaluated prior to impact appraisal are commonplace to the locality or scarce. Rarity often relates directly to importance. For example, the inter-relationship between buildings and open spaces may be a commonplace feature of the local townscape at the scheme level, but it has high importance and matters at a national scale. Conversely, the use of certain building materials or architectural styles could make an important contribution to townscape character locally, and thus be relatively rare within the townscape at the scheme level, but will be of less than regional importance. Retention of townscape character is as much about safeguarding and keeping the commonplace common as conserving and protecting the rare.

1.2.21 Importance - meaning:

• how important is this feature/attribute;
• at what level, for example, high, medium, or low and at national/regional/local level;
• to whom is it important.

1.2.22 For example, an individual building or group of buildings e.g. local authority offices, may be of very high importance at the local level, both in symbolic significance and as a townscape element framing views of the skyline, but do not figure at a regional or national level. In answering this question, qualitative judgements must be made, but not just about townscape quality in isolation. Assessing importance is straightforward where recognised policy judgements about the importance of features (and their associated elements) have been made, for example, through the planning process. Designated structures and areas, such as listed buildings, registered parks and gardens and conservation areas will guide assessments of importance, but do not provide a simple definition of importance. For example, Conservation Areas should not be seen as of only local importance, as local authorities are responsible for making these designations. However it must be recognised that the majority of the urban environment comprises undesignated townscapes, which can also be of high quality and of great importance. This will, out of necessity, be both a matter for professional judgement (for example quality, survival, diversity) and public perception (for example, local views and walks with cultural connotations and associations). The subjectivity of assessing importance is an integral part of townscape appraisal and should not be regarded as a weakness of it. This approach also enables policies with environmental objectives based on quality to be set within the context of character assessment and appraisal.

1.2.23 Substitutability - This column identifies whether townscape features and their constituent elements are substitutable or not within a given time frame. Most townscape functions can be replaced to some extent.

1.2.24 Changes in do-minimum - Change is a constant feature of the urban environment and reflects the dynamic nature of humans and their activities. The characteristics of the urban environment and our perceptions of them are constantly changing. Physical and social characteristics change as buildings, structures, routes and squares are added, removed, modified or their use altered. People's perceptions also change as, over time, their values change. In addition, as people move in and away from an urban area, society's collective perceptions about the urban environment will alter. Change in the urban environment may arise as a result of specific projects (e.g. a new building), changes in transport and non-transport policies (e.g. the introduction of traffic calming measures, or new housing policies) or as a result of other influences (e.g. changes in cultural preferences). Due to its changing nature, the urban environment has great potential to be enhanced by change. Equally, the potential for an urban area to change for the better, either through positive intervention or in a more evolutionary manner, can be stymied by unsympathetic proposals. It is therefore important that impacts are appraised with a good understanding of the dynamics of an urban area, including its potential. These changes, which will or could occur in the absence of specific transport plans - the do minimum scenario - need to be taken into account in appraising specific transport plans. This column in the worksheet should be used to identify the key changes that will occur in the absence of the transport proposal.

1.2.25 Impact - This column should be used to systematically describe and score the potential impacts of the scheme proposals on the townscape features/attributes. These should have been succinctly described and categorised against the indicators set out above. In assessing impact, the information on 'Importance', 'Substitutability' and 'Change in do minimum' will be particularly relevant. All impacts on the townscape, both adverse (damaging) and beneficial (enhancing), must be identified along with their predicted magnitude. The significance of each separate impact can then be appraised and scored. Any uncertainties over any of these aspects should be explained. The views of all the relevant authorities, statutory bodies, organisations and local residents should be brought to bear in making a decision as to the extent and significance of the impacts on the character and quality of each townscape feature and its constituent elements. This will be easier where an Environmental Statement exists for a scheme. Where such information does not exist it should still be possible, however, to make a preliminary judgement of impacts. It will be critical to the appraisal process to address how the proposal could impact on and change:

• the character of the townscape such as effects on the locally distinctive pattern of townscape elements;
• the ambience of an urban area and the way people interact with the townscape; and
• the tolerance of the townscape to accommodate further change.

1.2.26 Although inherent mitigation within the design of the proposal will ameliorate the impacts on specific townscape features and elements, it may be questionable as to how far such proposals can be successfully implemented. Where there is any doubt as to how far such measures can be implemented, this must be made clear in the worksheet, either under Impact or Additional Mitigation, with further explanation in the Qualitative statement if necessary.

1.2.27 In order to score impacts on individual features, account should be taken of the most relevant statements that are included to help define the seven point textual scale (Table 1). These definitions are needed in order to arrive at an overall score for townscape.

1.2.28 Additional mitigation is the last criterion in the table to be considered for each feature in turn. It is accepted that any scheme design will include appropriate mitigation measures as part of its design to achieve best fit within the townscape. The impact of each scheme on the townscape should be judged on this basis - Additional Mitigation should not be taken into account. However, in appraising the impact of a scheme on townscape character, it should also be possible to consider whether further, specific mitigation should be considered over and above the design objectives of the scheme proposals. This will enable new ideas for mitigation not expressed in Environmental Statements to be considered to determine whether all mitigation measures proposed will be:

• beneficial and cause the scheme to enrich and enhance the character of the townscape, or
• essential to neutralise the impact of the scheme proposed on the character of the townscape, or
• ineffective in reducing/minimising the impact of the scheme.

In this way all scheme proposals should be judged on a comparative basis.

Overall Impact Scoring

1.2.29 To arrive at an overall impact score for townscape it will be necessary to evaluate the significance of each of the individual impact scores for each townscape feature. An important pointer will be the impact score for "summary of townscape character" as this should best indicate how well the proposal would fit with the townscape. However, even when a proposal would fit well with urban environment, there may be an impact on particular townscape features and elements that could dominate the initial fit. For example, a well-designed proposal may be easily mitigated for, but it could nevertheless, because of the chosen alignment, bisect and fragment the form and social character of an important and nationally significant townscape element.

1.2.30 The overall impact on the townscape is summarised using the Appraisal Summary Table's standard seven point scale (Slight, Moderate or Large Beneficial or Adverse, plus Neutral). The definition of the points on this scale are not fixed and finite. Analysts should recognise that the local processes of character description and capital appraisal may switch proposals either way between points on the scale. This open flexibility is necessary to accommodate the complexity of townscape appraisal and community perception.

1.2.31 The nature of the impact (after construction of the proposal and maturation of mitigatory measures) for each point on the scale is set out below, with statements reflecting the appraisal process described in this guidance. These statements are for guidance in determining impacts. For a proposal to qualify for a particular score, most of the statements relating to that score must apply.

Qualitative Comment on the Effects of an Option

This qualitative box on the Appraisal Summary Table should state whether features and elements present in the townscape are typical of the locality and summarise the overall effect of the project or proposal on the townscape.

1.3 Methodology for Strategies

1.3.1 The level of detail available on the potential impacts at the strategic level will be considerably less than for project/corridor studies. Although data on the character and importance of the townscape may be relatively detailed, it is likely that the available impact data will be limited to changes in traffic levels and number of settlements within an area that are affected by the project. However using the principles discussed above, it should be possible to gain some understanding of the impact of a strategic proposal on townscape by applying the following three stage approach.

• Describe the communities (cities, towns, villages) that would be affected by the proposal. The descriptions should identify the key urban characteristics of each settlement. The extent to which this is possible will depend on the type of transport modelling exercise that has been undertaken. For example, a proposal might run through a medium-sized historic town, experiencing rapid growth due to the location of high technology companies. Where it is not possible to identify specific communities, it will be necessary to characterise the area. For example, a proposal might run through an area which contains small former industrial towns, now experiencing high levels of unemployment and whose urban fabric is being run down.
• Appraise the townscape capital of each community, or, where this is not possible, the area covered by the strategy. This appraisal will need to assess: the importance of these characteristics; why and who they are important to; and their inter-relationships with other environmental attributes.
• Describe and assess how the strategy will impact on the community or area. In the absence of much detailed information, it may only be possible to say whether an option has a positive, neutral, or negative impact.

2 Application of TAG to Highway Schemes

This section provides advice on the links between TAG's treatment of the townscape sub-objective and the advice given in Volume 11 of the Design Manual for Roads and Bridges (DMRB), which deals with the environmental assessment of highway projects. An explanation of the correspondence between the advice set out in TAG and DMRB is given in Applying the multi-modal new approach to appraisal to highway schemes (TAG Unit 2.6).

2.1 Methods and Worksheets

2.1.1 DMRB does not specifically have a townscape section, because the Manual was originally developed for inter-urban schemes, although 11.3.5.8 is a short sub-section of Landscape effects called Variations for Urban Schemes. The visual impact assessment forms a prominent part of any landscape or townscape assessment under DMRB.

2.1.2 In TAG, the Townscape worksheet follows the Landscape worksheet with features modified to Layout, Density and Mix, Scale, Appearance, Human Interaction, Cultural and Land Use. The indicators for Townscape are Scale it Matters, Rarity, Importance, Substitutability, and Changes in Do Minimum. These are the same as Landscape except that Townscape includes Changes in Do Minimum to better reflect the accelerated rate of urban change. The four step assessment mirrors that for Landscape, and guidance is given on features and indicators.

2.1.3 The worksheet and AST should compare do-minimum with the proposal. Analysts should ensure that the benefits resulting from traffic relief to existing roads is considered and included in the balance as this aspect is not covered in any detail in TAG. This could be particularly significant for a bypass project.

2.1.4 TAG acknowledges that the boundaries between townscape, landscape and occasionally heritage can be difficult to distinguish. Where a scheme is predominantly rural or urban, double counting and confusion may be avoided by omitting the redundant worksheet and recording 'not fully assessed' on the AST. Again, bypasses are an exception since the new road will probably be in a rural (landscape) setting but the urban (townscape) benefits to the bypassed community must not be forgotten.

2.2 Data Transformation from DMRB to TAG

2.3 DMRB Stages 1 and 2/ TAG

2.3.1 Although DMRB does not specifically describe Stages 1 and 2 for urban schemes, the information may be derived from the Landscape effects section.

2.3.2 Stage 1 DMRB requires a constraints plan and a statement of the likely effects of the proposal. A brief visual survey will be required. The information gained can be used to populate the TAG Worksheet. Limitations and assumptions made should be made clear in the qualitative comments section at the end of the worksheet.

2.3.3 Stage 2 will include a more detailed analysis of the urban character and the route will have been developed to some extent. The traffic re-assignment to a bypass should be known (forecastable) at this stage. Again, all known information of relevance should be used in the TAG Worksheet, and limitations and assumptions made clear.

Table 1 Landscape - Definitions of Overall Assessment Scores

Worksheet 1 Environment: Townscape

3. Further Information

The following documents provide information that follows on directly from the key topics covered in this TAG Unit.

4. Document Provenance

This Transport Analysis Guidance (TAG) Unit is based on Chapter 4, Section 8 of Guidance on the Methodology for Multi-Modal Studies Volume 2 (DETR, 2000). Section 2 is taken from Applying the Multi-Modal New Approach to Appraisal to Highway Schemes (Bridging Document).

Technical queries and comments on this TAG Unit should be referred to:

Integrated Transport Economics and Appraisal (ITEA) Division
Department for Transport
Zone 3/08 Great Minster House
76 Marsham Street
London
SW1P 4DR
itea@dft.gsi.gov.uk
Tel 020 7944 6176
Fax 020 7944 2198