PLANNING FOR SUSTAINABLE TRAVEL: INTEGRATING SPATIAL PLANNING AND TRANSPORT Dr Robin Hickman Halcrow Group and University of Oxford (Transport Studies Unit) Catherine Seaborn Halcrow Group Peter Headicar Oxford Brookes University (Department of Planning) Professor David Banister University of Oxford (Transport Studies Unit) 1. INTRODUCTION Urban structure1 and mobility appear to be inextricably linked. Using spatial planning more efficiently is at the heart of the challenge to achieve sustainable mobility. However the effective integration of spatial planning and transport has proved difficult to achieve in practice. In the UK the debate has developed, in the government and practice arenas, over the last 50 years2, and more recently focused on reducing the need to travel, especially by car. The aspiration is thus directed at improving choice for different means of travel, anticipating that this will lead to gains in sustainability terms. This however is a step removed from targeting a reduction in actual travel by car. Such ‘exhortation at the margins’ only takes us so far on the pathway towards sustainable travel the scale of traffic growth in the UK has arguably reduced as a result of policy initiatives, especially in urban centres, but traffic levels, congestion and carbon dioxide (CO2) emissions continue to rise in many areas. In most places walking, cycling and bus use are currently static at best and often still in long-term decline. Car dependency is often ‘built in’ under current and envisaged development patterns. Hence present policies are not achieving greater sustainability in travel behaviour. This is a policy and practice dilemma that has yet to be resolved. This paper considers the relationships evident between urban structure and travel. It draws on a study, ‘Planning for Sustainable Travel’, for the Commission for Integrated Transport (2008-09)3. It seeks to illustrate the important role that spatial planning can play, in practice, and particularly at the strategic scale, in enabling greater sustainability in travel patterns. It argues that a greater emphasis needs to be placed on reducing average per capita travel by car as the context and driver for greater integration in spatial planning and travel. The paper is structured in five main parts, covering the literature, the drivers for an improved approach, some recent trends, opportunities and conclusions. 2. THE PREVIOUS LITERATURE The interrelationships between urban structure and travel are complex. The location of activities – homes, workplaces, leisure, health, education and other facilities – act as the ‘physical structuring framework’ for travel. Authors have debated whether built environment variables are associated with energy consumption in travel, with much discussion over the strength and nature of relationships (e.g. Newman and Kenworthy, 1989 and 1999; Breheny, 1992; Banister et al, 1994; Cervero, 1996; Ecotec, 1993; Naess and Sandberg, 1996; Kitamura et al, 1997; Headicar and Curtis, 1998; Boarnet and Crane, 1999; Stead, 2001; Schwanen and Mokhtarian, 2005; Handy et al, 2005; Banister and Hickman, 2006; and many more).

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The analysis has become more sophisticated over time, with increasing consideration of multi-variate relationships and attitudinal and cultural contexts, including a recent focus on self selection issues (the influence of attitudes on people’s location choices and hence travel behaviour). Socio-economic, attitudinal and contextual characteristics all play important roles in the demand for travel, alongside the requirements of the trip. However, the empirical evidence demonstrates that there are significant associations between the built environment and travel, even after accounting for wider influences (Ewing and Cervero, 2001; Bohte et al, 2009; Naess, 2009; Cao et al, 2009; and others). Figure 1 presents the factors influencing travel demand, and it can be seen that urban structure plays an important role. The current debate is more over the nature and strength of that role, and how urban planning can be more fully utilised alongside other interventions. This builds upon the sustainable mobility paradigm and the means by which sustainable travel can be integrated into the pattern of urban form (Banister, 2008). Figure 1: Urban Structure as Enabler of Sustainable Travel

3. DRIVERS FOR AN IMPROVED APPROACH The need for more effective spatial planning derives from the combination of at least two sets of factors. The first is the limited success over the last 15 years in achieving actual reductions in car travel and greater use of non-car modes (other than rail). The second is greater awareness of the need to bring about such changes. This includes three main areas of concern: 1. Projected growth in traffic and worsening congestion, especially on inter-urban roads (Headicar, 2009). The Government’s Ten Year Plan acknowledged that the increased highway investment would not accommodate traffic demand over the longer term and the 2004 White Paper proposed a national system of road pricing to ameliorate the situation. The difficulties experienced in implementing road pricing in the years since has not yet been countered by any alternative strategy. 2. The climate change imperative: the UK government has recently adopted an 80% CO2 emission reduction target by 2050 on 1990 levels (Climate Change Act, 2008).

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Personal motorised travel currently represents nearly 25% of total UK emissions by end-user. 3. The long-run availability and price of oil and the vulnerability of the transport sector to oil price shocks (Strahan, 2007). A further issue which does not currently receive adequate attention is the difficulty of maintaining accessibility and ‘inclusion’ amongst people without use of a car (especially the increasing number of elderly people, and those living in less urbanised areas) in a society whose functioning and spatial organisation is primarily predicated on car use. Expected cuts in public spending during the post-recession era (e.g. for welfare services and subsidised transport) are likely to bring this issue into greater focus. Each of the above concerns can be considered important dimensions to the over-arching principle of sustainable development. Although some transport policy initiatives are directed at them individually it is clear that, when considering the appropriate spatial policy response, a more coordinated approach is required. Planning Policy Statement 1 (PPS1) (DCLG, 2005) addresses the spatial planning implications of sustainable development in general, but the full extent of the implications of these with respect to transport is not yet sufficiently recognised. The form and pattern of settlements is central to the argument, as comprehensive development control measures (introduced 60 years ago) have evolved in the context of large and continuing increases in car use. An equivalent timescale may be needed to introduce a changed form and functioning of settlements embodying a quite different set of transport precepts appropriate for sustainable development. The increment of change occurring within a single period of the statutory development planning system (15 years or so) is relatively short, when compared with the continuing influence of the established building stock and the patterns of activity and travel associated with it. However, when placed against the background of a longer-term vision, planning can begin to alter the inherited pattern of travel behaviour and establish a changed trajectory for the future. A much stronger forward-looking ‘futures’ aspect to policy making, building on the recent developments in transport scenario building would be one way to progress this longer term perspective. Backcasting methodologies provide one approach, where scenarios for 20-40 years into the future are ‘cast back’ to develop pathways, timelines and programmes for delivery (Hickman and Banister, 2007). Integrated planning and sustainable transport can act much more effectively within this longer term framework. Although the overall rate of traffic growth in the UK has slowed during the last decade, largely due to the levelling off in per capita car use, forecast increases in population (14% between 2003-2025) mean that this trend of lessening car use needs to be extended over several decades if traffic volumes are not to rise considerably. This is the context in which traditional tenets of development planning need to be re-appraised. The objective of ‘reducing the need to travel’ is already recognised in Planning Policy Guidance 13 (PPG13) but the practical response has been articulated largely in terms of the form and management of individual towns and small developments. Much greater attention needs to be given to the bulk of car mileage (and an increasing proportion of the total), which this arises from medium and longer distance trips between or wholly outside urban areas. The growth in longer distance car trips means that more attention should be given, at an early stage in the planning process, to analysing strategic location options in terms of their ability to minimise such trips, or (where they are perceived as unavoidable) in selecting places where the greatest potential exists to offer a competitive non-car alternative. It follows that a greater strategic emphasis is required in analysis and implementation work in the planning and transport fields. This complements the present micro-level focus on the

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design of internal layouts (inspired by the publication of Manual for Streets, DfT, 2007a), ‘Smarter Choice’ behavioural measures (after Cairns et al, 2004) and Transport Assessments of individual development proposals. Although these initiatives are very welcome, the basic pattern of trip-making (and hence the volume of travel) is effectively preordained by the strategic spatial framework and the existing network of routes. The practicable extent of influence at the lower spatial scales is limited to reducing the car driver share by a few percentage points at best, usually focusing on shorter distance trips. A more comprehensive approach would aim to reduce average trip lengths, by reducing travel between towns, and this needs to be complemented by a more systematic approach to reducing the car share of travel within them. The scope for reducing the car share of trips between towns is possible, but this would require more fundamental changes in transport policy to create the requisite opportunities and to extend the principles of traffic demand management into the inter-urban sphere (Headicar, 2009). At present, as noted above, a variety of measures is already employed to encourage modal shift on individual types of trip but these are all implemented in the context of high and rising levels of household car ownership which severely constrain their overall effectiveness. Research has demonstrated that car availability is the most important single factor contributing to levels of car use (Stead, 2001). It follows that if per capita car use is to be reduced more attention needs to be given to the combination of development planning, travel planning and traffic demand management policies within a given urban area, which in turn would create an environment in which it is both feasible and attractive to reduce private car ownership. Although the rise in car ownership per household may seem inexorable (at about 1% per annum), this aggregate change is in fact the net difference between much greater numbers of households gaining or relinquishing a car during any one year (Goodwin et al, 2004). It would require only a small rebalancing of these gain and loss rates for overall car ownership to reduce. Relinquishing, or not acquiring, a private car will be most attractive in situations where people do not, or do not need to, use a vehicle on a daily basis. School and workplace travel plans, including arrangements for business journeys, have a significant contribution here. If the need for car use can be removed from these journeys, then households have the opportunity to review their car ownership and travel arrangements more broadly. These may be prompted by exercises in personalised travel planning which identify the financial and environmental gains to be made and linked with the development of alternative forms of access (car hire, car clubs, car pools and car share) for trips where car use is needed. Together with the promotion of non-car modes and complementary policies of parking provision and management at home and destination trip ends, the present spiral of increasing private car ownership and use may be reduced or even reversed. 4. SOME EVIDENCE The early days of the ‘transport planning profession’ included consideration and quantification of relationships between the type and density of land use activity and the generation of trips. This expertise was used in the UK in the 1960s, and even up to the late 1980s and beyond, to demonstrate the prospective growth in traffic associated with rapid increases in car ownership and the implied need for new scales and forms of road infrastructure. Many contemporary problems of unsustainable travel arise from the resulting transformation of urban areas (both new and redeveloped) in ways which have implicitly promoted car use and deterred other modes (Headicar, 2003). Amongst previously developed areas however, the extent of physical change has been very variable, leading to marked differences spatially in car and other modal use per capita. Together with associated social norms these differences imply that policy responses will need to differ contextually (Table 1).

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Table 1: Modal Use Per Capita Government Office Region (GOR)

All Modes

Car Driver

Car Passenger

Bus

Train

Walk

Cycle

Other

East Midlands

7,269

4,112

1,998

251

429

216

48

215

East of England

8,320

4,448

2,393

227

740

202

51

257

London

5,420

1,876

1,165

519

1,266

230

58

306

North East

5,998

2,954

1,626

499

281

209

23

407

North West

6,629

3,595

1,811

372

389

205

34

223

South East

8,400

4,489

2,309

251

730

191

49

381

South West

8,116

4,311

2,618

299

317

218

42

311

West Midlands

6,557

3,642

1,997

381

193

163

22

160

Yorkshire & Humber

6,818

3,546

2,061

354

369

205

36

246

Scotland

7,338

3,500

2,229

485

355

191

21

557

Wales

7,346

3,984

2,427

346

163

158

22

246

(National Travel Survey, 2002-06)

A number of relationships between urban structure and travel can be identified using the National Travel Survey (DfT, combined data 2002-06)1. Residential population density, settlement size and type, accessibility, and various socio-economic characteristics are all significantly related to travel distance and mode share. For example: Density - there is (broadly) an inverse linear relationship between density and travel, where increased density is associated with reduced travel distance, particularly by car (Figure 2). However, the 15-30 and 30-50 persons per hectare (pph) density bands (which embrace most built-up areas) have similar per capita travel, hence the trends within the mid density ranges are not hugely clear. Car drivers in Great Britain average 3,660 miles per annum (51% mode share) in areas that have an average density of 2.5 pph. In London, a lower average distance by car is evident at 1,876 miles per annum (35% mode share, and a higher average density of 46 pph). The car driver and passenger mode share also reduces markedly, from 83% at densities of 5-15 pph to 44% at densities over 50 pph. Distance and mode share by public transport increases with density, particularly over 30 pph. Walking distance is similar over most densities but greater in the highest density category of over 50 pph. Settlement size/area type - there is (broadly) an inverse linear relationship with increased average distance travelled as settlement size decreases. The largest differential is between inner London (an average of 4,673 miles per person per annum) and rural areas (an average of 9,806 miles per annum). Outer London performs more like the other metropolitan areas in terms of average distance travelled. The highest distances travelled in non-rural areas are found in the smaller urban areas, particularly those with a population under 25,000 (Figure 3). The car driver mode share also increases such that, at the extreme, residents of rural areas have a per capita car driver mileage over 50% higher than the national average. The highest distances travelled in non-rural areas, both in total and as car driver, are found in the smaller urban areas, particularly with a population under 25,000. 1

More detailed analysis, including multi-variate analysis, is included in the background technical report to the main study (Hickman et al., 2009).

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r L Inn e on d o r Lo nd n W Glas Urb on an go Gr est w ea Ar M U i te e r M dlan rba a n d an sU Ar ch W es rba ea es te n tY A or r U r b re a ks an h Liv ire U Ar e er r po ban a o A l Ty ne Urb rea sid an e Ar U ea Ur rb an Ur ba n ba Ar A ea n Ar rea > ea Ur 10 250 ba K n 0K Ar e 2 Ur ba a 50 50K n K Ur Are - 10 a 0K ba 2 n Ar 5K e 5 Ur ba a 10 0K n K Ar ea 25K 3K Ru 10K ra lA re a

Ou te

Annual Distance Travelled per Individual (miles) Annual Distance Travelled per Individual (miles)

Figure 2: Density and Travel

Car Driver 8000 Car Passenger

0-1

Car Driver 10000 9000 8000 7000 6000 5000 4000 3000 2000 1000 0 Car Passenger

Bus Train

Bus Train

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Walk

Cycle

1-5 5 - 15 15 - 30 30 - 50 Population Density (People per Hectare)

Other

7000

6000

5000

4000

3000

2000

1000

0 50+

NTS, 2002-06

Figure 3: Settlement Size and Travel

Cycle Other

Area Type

NTS, 2002-06

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Current and future attempts at influencing land use patterns and promoting more sustainable travel need to be seen against the background of the changes taking place in society, where ingrained, dominant and long term trends are evident, including counter-urbanisation and traffic volume growth. In empirical terms, the most significant associations are found when a range of urban planning, socio-economic and attitudinal variables are considered relative to travel behaviour. The implications for policy making are that packages of interventions (density, location, accessibility, neighbourhood design) need to be considered when planning for greater sustainability in travel. 5. OPPORTUNITIES There are numerous opportunities to generate more appropriate spatial planning policies and to positively influence the built environment, such that the outcomes promote sustainable travel. Based on an extensive literature review as well as interviews with planners and others working at various levels of government across the UK, the key principles are presented for encouraging sustainable travel through the current UK planning system. The built environment and planning need to be much more closely linked to transport so that they both work in the same direction to achieve sustainable development, and this objective is a responsibility for government at all levels working closely with business and local communities. Integrated land use planning and urban design depends on creating local neighbourhoods with mixed use residential areas that are well connected by public transport to employment centres and other facilities. But they also require a sense of community, ownership and involvement in determining local priorities, so that safe, secure and high quality neighbourhoods result. In the planning literature, this dynamic has been characterised as the ‘3Ds’, covering Density, Diversity and Design (Cervero and Kockelman, 1997), or as an extended version of ‘5Ds’, covering Density, Diversity, Design, Distance (to public transport) and Destination Accessibility (Cervero et al., 2009). For example, by increasing density and accessibility with a range of local facilities, it is possible to reduce mobility and the need to travel. As well as having environmental benefits and moving towards sustainable transport, it also promotes greater social inclusion and equity. In this paper we have extended the 5Ds to 11 themes that need to be addressed. The range of interventions available to land use and transport planners has been underestimated and there needs to be a much clearer demonstration of the potential for better integration and a resulting increase in sustainable transport. At the strategic level, there are issues already discussed (section 4) relating to settlement size (theme 1), strategic development location (theme 2) and the strategic transport network (theme 3). The 5Ds cover the more local level of actions, including density (theme 4) and jobs-housing balance (theme 5), accessibility (theme 6), and the design issues, here interpreted as development site location (theme 7), mixed use (theme 8), neighbourhood design and street layout (theme 9). The distance characteristic has been extended to include travel demand management (theme 10) and parking (theme 11) that are the two key transport policy options over which local planners have considerable control, but the operation of the public transport system would be an important element here. The 11 themes map well onto the 5Ds (Cervero et al., 2009), as shown in Table 2. The exception of the diversity heading that seems to be more of a generic characteristic, as it covers all the themes. It is not the intention here to create ‘clone settlements’ that all seem to be the same, but to create a variety of sustainable settlements that allow for local distinctiveness, character and individuality (Simms et al., 2005). The 11 themes, covering 3 strategic areas and 8 more local ones are now described in greater detail.

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Table 2: Strategic and Local Themes and 5Ds Strategic Themes

Local Themes

T1: Settlement Size T2: Strategic Development Location

T4: Density and T5: Jobs-housing balance T7: Development site location, T8: Mix of uses and T9: Neighbourhood design and street layout T6: Accessibility to key facilities T10: Travel demand management and T11: Parking

T3: Strategic Transport Network

5Ds (from Cervero et al., 2009) Density Design

Destination accessibility Distance to public transport Diversity

Theme 1: Settlement Size Settlement size refers to the total population or number of dwellings within a contiguous built-up area. Larger settlements normally provide a greater mix of employment, shops and other services including representation of more specialised types. As a result there is greater likelihood of residents finding jobs and utilising facilities, or of services drawing their employees and customers, from within the same urban area, leading to the possibility of greater ‘self-containment’. This tends to lessen average trip lengths and in particular reduces the need for inter-urban travel, which at present is disproportionately car-based. Larger settlements are also associated with higher development densities and higher travel volumes on their main corridors. Together these facilitate higher levels of public transport service to be operated on a commercial basis and provide greater opportunities for journeys to be made by walking and cycling. They also both require and facilitate a managed approach to car parking which contributes to lower car ownership and use. In regional and sub-regional planning, policy makers are advised to consider the advantages for sustainable travel of locating the majority of new development in or adjacent to the largest urban areas within the region. New development should not simply replicate the existing distribution of population across urban settlements, or reflects recent growth patterns but to be planned with an explicit concern over sustainable travel. A selective review of Green Belt needs to be undertaken and similar urban containment policies (from the perspective of sustainable travel) considered, where the expansion of these larger settlements has been prevented in recent decades. It may not always be practicable or desirable to maximise development in or adjacent to the largest urban areas within any region/sub-region because of the local incidence of housing need in other areas, support for smaller communities and their services, restricted land availability and/or environmental or infrastructure constraints. However, subject to issues of strategic development location, expansion of larger settlements (25,000 population at a minimum) is generally preferable to ‘leapfrogging’ development to smaller towns or ‘spreading’ development across a number of settlements. Theme 2: Strategic Development Location Alongside considerations of settlement size, strategic development location refers to the selection of areas for major new development (residential, employment, leisure and retail) within regions and sub-regions, including the spatial distribution of housing and employment within Growth Areas and between Growth Points and other urban centres (Figure 4). In the numerical apportionment of planned development (e.g. between local planning authority areas) there are strong links with jobs-housing balance and, where particular places are identified, with the strategic transport network. Strategic development location is also relevant to the allocation of development within the areas of individual local planning authorities (e.g. in their Local Development Framework

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Core Strategies) where this has not already been identified in the Regional Spatial Strategy. The aim should be to locate development where travel by car is likely to be minimised both in terms of trip length and mode share, where opportunities exist, or can be developed, to promote the use of non-car modes, and where good accessibility is available without requiring car use or relying on local public transport services, which depend on subsidy over the long term. Figure 4: Strategic Development Location and Travel

In regional and sub-regional planning, policy makers are advised to locate major employment, retail and leisure uses with a sub-regional catchment, preferably in existing city and town centres, or alternatively (where the physical opportunity is not available), at other locations which can be accessed conveniently by public transport from the relevant catchment area. Development in non-central locations, close to junctions with motorways and similar dual-carriageway routes should all be avoided, unless they enjoy exceptional public transport accessibility (e.g. a rail ‘parkway’ station). This will discourage short and medium-distance travel by car on strategic highways and is especially important in cases where new housing is likely to be attractive as a ‘dormitory community’ for people working in major urban areas accessible by the route. Locations for additional housing should also have regard to the proportion of trips likely to be made within the home settlement (i.e. the degree of ‘self-containment’), and the average distance of trips to places outside the home settlement and the likely proportion to be made by public transport. Where significant outcommuting is seen as inevitable, new housing should be located in places which already enjoy good, or can receive improved, public transport accessibility to the relevant external destination(s), for example by virtue of a rail service or express bus route.

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Theme 3: Strategic Transport Network The strategic transport network refers to transport infrastructure that supports medium and long-distance travel, generally between towns and cities or along major corridors in urban areas (Figure 5). It includes all modes whose configuration and design serves, and could potentially influence, spatial development patterns, e.g. rail, bus priority route and highway. To increase the sustainability of longer-distance travel generated between settlements, the aim should be to increase the efficiency and reliability of the existing public transport network (rail and bus) and invest in public transport infrastructure improvements, and to create development patterns that support public transport usage and discourage the use of the strategic highway network for car trips associated with daily trip purposes, e.g. commuting. Figure 5: Strategic Transport Network

Hence in regional and sub-regional planning, policy makers are advised to develop subregional and city-regional governance structures (e.g. Multi-Area Agreements) that support an effective process for achieving integration in transport and urban planning. Key public transport linkages and networks between cities and towns and within larger conurbations (in collaboration with national government) should be developed, and major development should be located near to nodes on this network where capacity exists or can be developed. The efficiency of the strategic transport network can be improved by increasing integration between modes, for example at important urban and edge-of-town interchanges and parkand-ride sites. Public transport infrastructure investments should be prioritised so that they support desired development patterns, and more efficient use of available road capacity through travel demand management measures (theme 10), with road space being reallocated to more sustainable modes. Theme 4: Density Density refers to the intensity of use of land. In UK planning practice, density is generally measured in dwellings per net hectare (dph), where the area includes developable residential land4. Density is relevant to planning debates at a strategic level, where density assumptions underpin estimates of the need for any additional development land

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requirement and where policies are set for framing master-plans for major development areas and for negotiations on development applications. Figure 6: Density and Travel

(Adapted from Rogers, 1997)

The objectives of sustainable travel are generally served by raising the density of development, particularly around public transport nodes (Figure 6). This contributes to lower transport energy consumption and CO2 emissions, greater scope for viable and attractive public transport services, and reduced car use in terms of both mode share and distance travelled. There is continued discussion as to appropriate density levels. PPS3 (DCLG, 2006) advises a “working minimum of 30 dwellings per hectare”. Llewelyn Davies (1997), Rogers (1997) and others have called for the use of higher densities. Much higher densities can be achieved in many areas, up to 50-100 dwellings per hectare (dph), and even 100-200 dph plus around important public transport interchanges. A set of density ranges can be developed for each local area reflecting contextual issues. In regional, sub-regional and local planning, policy makers are advised to consider the interrelationships between public transport accessibility, parking and density in the early stages of strategic planning processes (Integrated Regional Strategies and LDF Core Strategies), including beyond town centres and inner urban areas to include suburban areas. The highest density possible consistent with density range, quality of life and public transport availability considerations (existing and future) should be considered. Where new or enhanced public transport provision is envisaged the development form should be re-configured to support patronage, particularly where suburban, low densities surround stations or stops.

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Theme 5: Jobs-Housing Balance Jobs-housing balance refers to the approximately [equal] relationship of employment opportunities and workforce population within a geographic area. It is usually measured in terms of the proportion of jobs per worker. For example, a jobs-housing balance of 1.25 means there are 5 jobs for every 4 workers. Qualitative matching between skills, aspirations and job type is critically important as well as numerical balance. The aim of jobs-housing balance is to provide local employment opportunities that may reduce overall commuting distance among residents (and also the reverse – to provide homes near to workplaces). Like most of the urban structure variables, it is a necessary, but not sufficient condition for reducing the need to travel. Arguably it is more important at the strategic travel to work area level, or in peripheral and remote urban areas where opportunities for cross-area commuting are less. Policy makers are therefore advised to consider the different scales over which jobs-housing balance is best achieved. This can initially be conceived at regional, travel to work and urban area levels. Existing commute patterns, planned residential and employment locations and workforce characteristics should all be examined to ensure there are no mismatches which may encourage car dependency and long journey distances. Effective jobs-housing balances for urban areas are in the range 1.0-1.5. Increments of new growth should be of sufficient mix to provide balance at the strategic level. Large employment generators should be located at the most accessible locations by public transport, walking and cycling, i.e. those with the largest population catchments by these modes. Theme 6: Accessibility to Key Facilities Accessibility refers to the ease of reaching destinations or activities2. Places that are highly accessible can be reached by many people quickly, whereas inaccessible places can only be reached by a few people in the same amount of time (Figure 7). However there are important differences between the accessibility available by car and non-car modes and hence of people who do and do not have the option of car use. Typically the gap between car and non-car accessibility is least in relation to urban centres and greatest in rural areas and areas of social deprivation. Accessibility is conventionally perceived in physical travel terms, but electronic social interaction is becoming increasingly important. As yet there is little evidence of an aggregate substitution effect (with electronic travel replacing physical travel), but social interaction tends to increase. But this may change over time as the ‘network society’ takes off (e.g. Castells, 1996; Hall and Pain, 2006; Choo et al, 2005). Key facilities serve a wider catchment than the immediate neighbourhood in which they are situated. Examples include employment centres, shopping centres, hospitals, educational institutions, leisure centres and cultural attractions. The accessibility of key facilities is therefore of particular importance because they are major travel generators (for both employees and patrons) and because they determine the level of opportunities available across the social and geographical spectrum. The aim should be to locate and manage key facilities so that they will be conveniently accessible by public transport by users and employees within their planned catchment area. This means that they should support and facilitate the improvement of public transport services, but also minimise trip distances and travel time to individual facilities. Opportunities can be created for trip purposes to be combined in a journey to a single destination (i.e. a centre with a mix of uses), and the proportion of travel by non-car modes can be maximised. 2

Accessibility for persons with disabilities is also an important issue, and is covered in other guidance notes; a broader definition is taken here in terms of accessibility to destinations.

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Complementary land use and transport policies, travel demand management strategies and investment programmes can be pursued in the area more generally. Figure 7: Accessibility and Travel

Policy makers are therefore advised to locate key facilities within town, suburban and rural centres which relate to the catchment areas of the activities concerned, if this is practicable. Planning policy guidance requires the identification of a hierarchy of centres, and selection and assessment criteria for centres at the same level of hierarchy should include their relative accessibility by public transport from the residential population they are intended to serve and from the area where their workforce will be drawn. If the full requirement for major employment and key facilities cannot be met within established centres, consideration should be given to other locations on the public transport network which offer (or can be improved to offer) similar levels of accessibility from the relevant catchment area. Where key facilities (and/or major employment sites) must be developed outside established centres, include a mixed use element to facilitate multipurpose trips and travel demand management measures and controlled parking on site to complement parking restrictions in the vicinity. Theme 7: Development Site Location Development site location refers to the selection of sites for new housing or other developments. It covers the type of decision that would generally be taken early in the Local Development Framework (LDF) process (for housing within the context of figures set by the Regional Spatial Strategy). These decisions have a major impact on the volume of travel likely to be generated, the proportion by non-car modes and the accessibility (opportunities) available to different social groups. Development site location is also often a catalyst for transport interventions, helping to make viable new or enhanced transport facilities or to remedy existing traffic or environmental problems.

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Further opportunities may exist to promote the use of walking, cycling and public transport. Provision of an attractive level of public transport service which does not depend on (additional) subsidy over the longer term is key to its longer term stability. More generally, the utilisation and support for existing public transport services and community facilities in the locality is also key to stability. Services or facilities need to be incorporated within the development which will improve accessibility by sustainable modes, and forms car-free or low car provision housing could be considered. Policy makers are advised to adopt a systematic process of identifying and assessing sites for development which includes noting existing accessibility by car and public transport to/from employment and other key facilities (deficiencies in accessibility are unlikely to be remedied by transport measures that can be introduced as part of smaller scale development). It also needs an understanding in utilising existing transport infrastructure and services and minimising requirements for new public investment or additional support. This includes the exploitation of opportunities presented by the development, in combination with the location and quality of existing bus routes and local facilities, to bring about improvements in accessibility. Examples for larger towns include incorporating network links in the layout of development to enable existing urban bus services to be utilised and enhanced. Larger extensions may justify a dedicated bus service along a radial corridor with priority measures. For small towns, development should be focussed on radial corridors in order to utilise and support inter-urban bus services that run along them. Consideration should be given to the option of selective release of land at the edge of larger settlements and in public transport corridors (possibly requiring the local review of Green Belt or similar open land designations), taking into account the relative accessibility by public transport of alternative locations to jobs and major facilities, the likely difference in per capita car mileage, and the potential to ‘swap’ other locations for open space provision. Theme 8: Mix of Uses Mix of uses refers to the degree to which different land uses are contained within a geographic area, generally a building, street or neighbourhood. It may be specified within the masterplan for a development area or the brief for a particular development site. Within predominantly residential areas ‘mixed use’ generally refers to the provision of local facilities which enable many day to day activities to be undertaken on foot and ensure good accessibility without the need for car use. In predominantly business areas ‘mixed use development’ provides similar local opportunities for employees during or at either end of the working day. More generally it enables individuals to undertake multiple activities/stops in a single trip, and to encourage non-motorised trips through a diverse urban environment, e.g. a high street, rather than necessitating a ‘chain’ of motorised trips to separate, dispersed destinations. Policy makers are therefore advised to consider locating essential community facilities (e.g. grocers, local schools, banks) within walking distance of all homes in a neighbourhood in order to reduce travel distances, de-incentivise car ownership and foster social inclusion. This will require a certain density of housing in order to concentrate demand sufficiently for the shops and services to be economically viable. In addition they should identify complementary uses, such as a day-care and fitness centre or bookstores and cafes and support building types which facilitate co-location, so that individuals can reach more activities per trip. Where public transport is available, retail uses should be promoted that complement employment centres in order to increase public transport mode share.

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Theme 9: Neighbourhood Design and Street Layout Neighbourhood design refers to the scale, form and function of buildings and open space (including streetscapes). Street layout refers to the pattern of local streets, for example as ‘traditional’ grid networks, cul-de-sacs or hybrid forms (Figure 8). Both can have an impact on generated travel patterns. Sustainability objectives move transport planning at this scale beyond a preoccupation with vehicular throughput, to include consideration of transport routes as ‘places’ as well as ‘links’ (for a useful working typology see ‘Link and Place’, Jones, Boujenko and Marshall, 2008). Figure 8: Street Layout and Travel

(Adapted from Duany, Plater-Zyberk and Speck, 1992) Note the image contrasts poor permeability to the north of the road and better permeability to the south. The original diagram has been amended to provide linear high street style shopping to the south (originally mall style) and a more integral school location.

Policy makers are advised to encourage walking, cycling and public transport use (where applicable) through permeable, well-connected, ‘traditional’ grid street networks. Design should avoid circuitous, ‘surburban’, cul-de-sac street networks with few access points and lengthy routes to nearby locations. In new developments, provide safe and high-quality walking and cycling environments throughout. In existing developments, consider retrofitting footpaths and adding cycle lanes to improve the travel experience of walkers and cyclists. Sustainable modes can be given priority in terms of journey length and time (sometimes known as ‘filtered permeability’). The integration between new development and adjacent built-up areas needs to be assured in terms of street network, public transport services, footpaths/cycle routes and design standards, especially where the links involved are critical to delivering good local accessibility. Many recent good practice design advice and resources are available, including the Manual for Streets (DfT, 2007b) and the Urban Design Compendium2 (Roger Evans Associates,

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2007). CABE (2007) summarises a number of good practice streets and spaces in the UK. Area-specific urban design guidelines and codes can be developed as appropriate. These should include specific reference to street layout and design. Theme 10: Travel Demand Management Travel demand management (TDM, and sometimes known as ‘mobility management’) covers a wide range of measures aimed at reducing car use and its adverse impacts. They are complementary to the more traditional development components of spatial planning in promoting sustainable travel. Many of the organisational initiatives are known as ‘smarter choice’ behavioural measures (after Cairns et al, 2004). Possible TDM interventions can be listed under three main categories (Table 3), but there is not space here to discuss each of these separately. Table 3: TDM Interventions Organisational and Operational • Travel plans (workplace, school, residential, area-wide) •

Personalised travel planning.

•

Car pooling, car sharing and car clubs.

•

Company work hours, flexiworking, home working.

•

Home retailing and delivery.

•

Tele-activities and interaction.

•

Marketing/media campaigns.

•

Transport optimisation, peak congestion avoidance.

•

Slower speeds and ecological driving styles

Financial • Pricing regimes, including (where applicable) road user cordon charging, arealicensing schemes, continuous charging. •

Vehicle ownership taxes.

•

Public transport investment/subsidy.

•

Parking charges.

•

Bicycle investment/subsidy.

Infrastructure • Improved public transport facilities, including (where applicable) National Rail, Underground, light and ultra light rapid transit, guided bus and bus, etc. •

Demand responsive transport.

•

Park and ride.

•

Improved walking and cycling facilities.

•

Road space re-allocation and priority, traffic calming, access control and restrictions.

•

Streetscape design.

•

Parking

Policy makers are advised to complement the land use component of spatial strategies at regional, sub-regional and local levels, with the development of a rigorous TDM strategy which sets out to reduce per capita car use and lessen its adverse impacts. They should also develop and implement these strategies in an integrated manner (drawing on the full range of measures listed above) in order to maximise their effectiveness, thereby securing best overall value for money and creating travel environments in which, at the margin, lower private car ownership is a feasible and attractive option. The Travel Demonstration Towns pilot has included investment in many of these measures as a coordinated initiative and illustrates the type of strategy which is effective in reducing car-based travel (DfT, 2009). Such packages of interventions should be carried out in urban areas and new developments across the UK. Theme 11: Parking Parking refers to the amount of space planned for the storage of cars and other vehicles (on and off-street) in new development and to the management of space in existing and new developments. It also includes provision for two wheelers (powered) and bicycles. Because people do not necessarily park at or within their destination site, it is necessary to consider development-related policies in the context of local parking conditions more generally and of policies for the provision and management of on-street space and publicly available car parks.

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Parking policy is a central element in TDM and should therefore feature in spatial strategies at all levels. However is much under-utilised. It can be directed beyond the traditional objectives of ensuring safe and efficient conditions on individual highways to encourage less car use in order to improve traffic and environmental conditions in an area and to contribute to broader transport and sustainable development objectives. As noted above controlling parking through restriction of spaces and/or pricing typically complements a variety of measures designed to promote the use of non-car alternatives. It can also be linked to other objectives such as giving priority to low emission vehicles. Both the amount of parking space and the form in which it is provided (i.e. within the curtilage of private developments, in allocated or unallocated off-street spaces, and in onstreet bays) have implications for, and need to be consistent with, wider issues of neighbourhood design and street layout. It can also be conceived as an integral part of the design of ‘car free’ and ‘low car’ housing developments. Policy makers are advised to apply separate considerations to the main categories of development: business, retail and leisure and residential. These should be interpreted in relation to local density and public transport accessibility conditions and provide adequate access and temporary parking for delivery and service vehicles. Accommodation for future charging sites for electric or other alternatively fuelled vehicles should also be considered. Business (excluding retail and leisure) should explore the potential for reducing car commuting through the management of publicly available space and through the adoption of travel plans by employers, possibly with a gradual reduction of available space and a Workplace Parking Levy component. If pursued collectively on a neighbourhood basis this facilitates economies of scale in the provision of non-car alternatives and investment on a partnership basis. In addition they should develop coordinated parking strategies for Travel to Work Areas. Local planning and local transport authorities can work within a framework set by the Regional Strategy. For example, within Local Development Frameworks, maximum parking standards could be included for new employment development, together with thresholds for the preparation of Transport Assessments, and consideration given to the location of park and ride sites and any other major public car parks. Within Local Transport Plans, policies and proposals for controlled parking zones, workplace travel plans, workplace parking levies where applicable, and complementary transport improvements could all be included. For retail, leisure and similar uses, the alignment of the provision and pricing of public spaces with the opportunities available for access by non-car modes (since the car and noncar modes will be in more direct competition than is the case with commuting) having regard to the scale and nature of any competition between out of town developments with free parking and town centre policies. This includes the development of visitor travel plans with reference to customer catchment areas. For residential areas, the provision should include maximum parking standards for new residential development. In controlled parking areas, measures should be considered to encourage reduced levels of car ownership and smaller, more fuel efficient vehicles including the pattern of charges set for residents’ permits, a programme of personalised travel planning, the promotion of car club and car share schemes, walking and cycling and local public transport services and the preferential allocation of public parking places. In major new housing developments, similar measures should be pursued through residential travel plans negotiated as a condition of planning permission. The expected impacts of such measures should be used to amend the nationally generated forecasts of household car ownership in setting parking standards for new developments and lessen the requirement for parking space by providing shared spaces (some of these available for use by visitors). In controlled parking areas, access to shared space or separate garages should be subject to a

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rental charge. This is a more equitable distribution of the associated development costs and encourages households to review their car ownership levels. To discourage household cars ‘spilling over’ on to the street or other publicly available spaces (where garages are used for purposes other than car storage), the proportion of dwellings with their own private garages (with car ports or hard standing utilised instead) should be minimised. It is important to coordinate policies across local authority boundaries, and within and between settlements, so that local action is conceived within regional and sub-regional TDM strategies. There has been a recent trend to relax residential parking standards within some local authorities, but this should be resisted. In the absence of a national strategy for comprehensive road pricing, parking policies at both home and non-home trip ends remain a key tool in managing the demand for travel. 4. CONCLUSIONS Despite scepticism in some of the recent literature, it appears that spatial planning has an important role to play in helping to achieve sustainable travel. The socio-demographic dimension to travel behaviour is central to decisions made by individuals and businesses, and the role of attitudes to certain types of travel and living circumstance is beginning to be better understood. However the pattern of settlement, the distribution of land uses and physical structure of urban areas all appear to remain important in setting the ‘envelope for travel’. Critically, urban planning (including strategic and local forward planning, masterplanning and development control) is one of the factors influencing travel behaviour that is able to be affected through policy intervention at different spatial scales. ‘Integrating land use and transport planning’ is often put forward as a policy objective, but relatively little follows in practice at the strategic level (which most affects the volume and mode of travel). Traditional tenets of preventing urban sprawl remain in place, reinforced by more recent initiatives to resist car-dependent developments, utilise previously developed (brownfield) sites and raise housing densities. But too often new development is spread between towns in an area, following the historical settlement pattern or more recent shifts in the residential population not planned with sustainable travel in mind. The impact of new development on travel patterns is often overlooked and at best is very much a lower order consideration. This contributes to an increase in the overall volume of car travel. Planning and managing development in relation to a range of variables, including settlement size, development location, the transport network, density, jobs-housing balance, accessibility, mix of use, site location, neighbourhood design and street layout, traffic demand management and parking (our suggested 11 themes) can help in moving towards greater sustainability in travel lifestyles. The end objective in further integrating settlement structure and transport is to move beyond the current discourse, to enable and achieve more sustainable travel patterns. Greater regional and or sub-regional analysis is important, with new settlement growth understood in terms of the likely impact on the catchments for employment and other key services. A longer term aspect is also needed in decisionmaking. A greater focus on achieving reduced per capita car use, not least because of the climate change imperative, adds further impetus. This paper has taken the perspective of the policy maker, widely interpreted as a range of decision makers in both the public and private sectors. It may also seem to be rather prescriptive in trying to bring together the range and complexity of the different actions that are needed to further integrate land use and transport. But it is based on an extensive review and a series of detailed case studies and interviews with some of the key actors (Hickman et al., 2009). All of the empirical and contextual material has been taken from the UK experience, but the lessons drawn have a much wider relevance to the need for closer understanding of the processes that link our transport systems to the built environment. Too

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often in the past the different traditions of transport planners and those of urban and regional planners have followed different and often conflicting paths. Now, more than ever, it is important to bring the professions and traditions together so that they can truly work in a complementary manner to achieve sustainable transport and land use systems. Recent history has demonstrated that the transition to achieving sustainable travel is very difficult, certainly beyond the limited successful experience in the central parts of selected urban areas. The debate over relationships between the built environment and travel will continue to develop, with increasing sophistication. It is crucial that all interested parties are involved in that process, so that real progress can be made towards an integrated land use and transport system that respects environmental, social and economic concerns. Often it is not the knowledge and research that is lacking, but the effective application of this knowledge in practice.

Notes

1

‘Urban structure’ is defined as the spatial distribution and layout of activities, within a functional area (e.g. city-region) as well as within a particular town or other settlement. 2 See, for example, the Buchanan Report ‘Traffic in Towns’ (MOT, 1963), Transport Policy White Paper (DOT, 1977), Transport – The New Realism (Goodwin et al for RJRF, 1991), Transport and the Environment (RCEP, 1994), Planning Policy Guidance Note 13: Transport (DOE, 1994 and DETR, 2001), A New Deal for Transport White Paper (DETR, 1998), and even some of the more recent documents: Ecotowns Transport Worksheet (TCPA, 2008), Building Sustainable Transport into New Developments (DfT, 2008b). 3 Hickman, R., Seaborn, C., Headicar, P., Ashiru, O., Saxena, S., Banister, D. and Pharoah, T. (2009) Planning for Sustainable Travel. Summary Guide, web-based guidance and background technical report. London: Halcrow Group for CfIT. Details on www.plan4sustainabletravel.org 4 Other metrics can be used. For example, gross density includes all land (i.e. including major roads, parks, service facilities, etc.) and is often measured in terms of dwellings per hectare or persons per square kilometre. Gross density is useful for comparing densities across larger areas and for estimating potential public transport demand. Habitable room densities allow different house types to be accommodated. The more recent research is beginning to develop more effective measures of density and quality, e.g. number of useful facilities per area, such as bookstores or coffee shops.

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