Forecasting environmental equity: Air quality responses to road user charging in Leeds, UK

https://doi.org/10.1016/j.jenvman.2005.04.013Get rights and content

Abstract

Sustainable development requires that the goals of economic development, environmental protection and social justice are considered collectively when formulating development strategies. In the context of planning sustainable transport systems, trade-offs between the economy and the environment, and between the economy and social justice have received considerable attention. In contrast, much less attention has been paid to environmental equity, the trade-off between environmental and social justice goals, a significant omission given the growing attention to environmental justice by policy makers in the EU and elsewhere. In many countries, considerable effort has been made to develop clean transport systems by using, for example, technical, economic and planning instruments. However, little effort has been made to understand the distributive and environmental justice implications of these measures. This paper investigates the relationship between urban air quality (as NO2) and social deprivation for the city of Leeds, UK. Through application of a series of linked dynamic models of traffic simulation and assignment, vehicle emission, and pollutant dispersion, the environmental equity implications of a series of urban transport strategies, including road user cordon and distance-based charging, road network development, and emission control are assessed. Results indicate a significant degree of environmental inequity exists in Leeds. Analysis of the transport strategies indicates that this inequity will be reduced through natural fleet renewal, and, perhaps contrary to expectations, road user charging is also capable of promoting environmental equity. The environmental equity response is, however, sensitive to road pricing scheme design.

Introduction

Sustainable development has three widely agreed meta-goals: sustained economic development (inter-generational equity), environmental protection, and social justice (intra-generational equity) (WCED, 1987). Because there are trade-offs between these goals, all three must be addressed together if development is to be sustainable. Feitelson (2002) observes that, whilst trade-offs between economic development and the environment, and between economic development and social justice have received considerable attention, much less attention has been paid to the trade-off between environmental and social justice goals. Furthermore, this trade-off, often referred to as environmental justice (EJ), has rarely been coupled with issues related to transport.

As Agyeman and Evans (2004) note, EJ is a contested concept with many possible definitions. A recent definition is that contained in the US Commonwealth of Massachusetts EJ policy, which states that:

“Environmental justice is based on the principle that all people have a right to be protected from environmental pollution and to live in and enjoy a clean and healthful environment. Environmental justice is the equal protection and meaningful involvement of all people with respect to the development, implementation and enforcement of environmental laws, regulations and policies and the equitable distribution of environmental benefits” Commonwealth of Massachusetts (2002)

Agyeman and Evans (2004) note that this definition implies that EJ has “procedural (‘meaningful involvement of all people’) and substantive (‘right to live in and enjoy a clean and healthful environment’) aspects” and that “unlike most definitions, it makes the case that environmental justice policy should not only be reactive to environmental ‘bads’, but should also be proactive in the distribution and achievement of environmental ‘goods’ (a higher quality of life, a sustainable community)”. Other definitions of EJ are less explicit with respect to the procedural dimension, and emphasise the distribution of environmental quality. Cutter (1995), for example, defines EJ as “equal access to a clean environment and equal protection from possible environmental harm irrespective of race, income, class or any other differentiating feature of socio-economic status”. No attempt is made here to further define EJ or address EJ directly, but a clear distinction is drawn between EJ and environmental equity, the focus of the paper.

Environmental equity here refers to the social distribution of environmental quality (and specifically the distribution of NO2 by deprivation status). In contrast, EJ must also consider to what extent the observed distributions are ‘unfair’. One element of this interpretation is a consideration of how a particular distribution has arisen. Whilst such causality issues are poorly addressed in empirical EJ studies to date, numerous mechanisms by which an unequal distribution may arise have been postulated, ranging from deliberate discrimination within the planning system to natural socio-economic processes relating to neighbourhood change (for example, people may choose to locate in an area of low environmental quality to take advantage of local employment opportunities or a better quality house).

A second element in the consideration of fairness is the justice theory subscribed to by those making the EJ assessment, i.e. for a single distribution, different conclusions as to ‘fairness’ may be made depending upon whether the assessors consider a just distribution to be one where people get what they need, what they have a right to, or what they deserve. Thus understanding causality and the justice theory applied are key elements in the interpretation of environmental injustice. Such considerations (see Capek, 1993; Cutter, 1995; Liu, 2001; Walker and Mitchell, 2003 for further discussion), are, however, largely beyond the scope of this paper which addresses a more limited, but essential first step in EJ assessment, the identification of the social distribution of environmental quality, here after referred to as environmental equity assessment.

Environmental justice issues have received significant attention at the global level, most notably with respect to the relationship between developed and developing countries. Research in this field has, for example, addressed differential contributions to, and impacts of, climate change, and the distribution of the costs and benefits of natural resource exploitation, both issues where transport is important (Bhaskar, 1995). Local scale environmental equity issues, of the kind addressed by this paper, are in comparison much less studied. However, policy developments at the highest level (e.g. a Presidential order in the USA; a UN ECE convention on the environment) mean that in future, greater cognisance of local and regional environmental equity issues is required when evaluating projects, plans and policies that affect the environment.

In the USA, the analysis of EJ is now an important part of environmental and public health policy assessment. The US Environmental Protection Agency, for example, now addresses EJ in their National Environment Policy Act (NEPA) planning and decision-making process, defining ‘fair treatment’, as that where no group of people bear a disproportionate share of the environmental and adverse health impact of development (US EPA, 1995). This action was mandated by President Clinton's Executive order 12898 that directed “All Federal agencies to make environmental justice part of their mission, and to identify and address disproportionately high and adverse human health or environmental effects of their programs, policies, and activities on minority populations and low income populations” (President Clinton, 1994). A memorandum accompanying the order also requires that Federal agencies ensure that communities have access to relevant information and are given opportunities to effectively participate in agency actions that affect them.

These EJ responsibilities developed from the concerns expressed by civil rights activists in the 1970s and 1980s, who demonstrated that landfills and polluting industries were disproportionately sited within predominantly black communities or indigenous peoples' reservations (Bullard, 1990; Lavelle and Coyle, 1992). However, class actions brought against civil authorities on the grounds of unjust planning decisions have proved largely unsuccessful, for two reasons. Firstly, poor empirical foundations of EJ analyses have precluded authoritative statements on inequitable relationships between racial or income groups, and environmental problems and associated health burdens (Bowen, 2002). Secondly, where evidence has clearly pointed to environmental inequity, intentional discrimination on the part of the responsible authority or developer has rarely been proven (Taylor, 1999). Although the Presidential order creates no legal rights, litigation will be an important mechanism in determining how environmental inequities are determined and evaluated within the justice framework created by the order.

In Europe and the UK, EJ issues are also attracting significant attention. Recently, EC directives have been passed on access to environmental information (2003/4/EC) and participation in environmental decision-making (2003/35/EC). These directives were introduced to meet the provisions of the UN Economic Commission for Europe (UN ECE, 1999) ‘Convention on Access to Information, Public Participation in Decision Making and Access to Justice in Environmental Matters’ (the Arhus convention), which came into force in 2001. A third EC directive on access to justice in environmental matters is proposed, and has the objective of giving the public access to judicial and independent procedures to challenge acts or omissions by public authorities and private persons which contravene environmental laws. This area is currently under formal discussion to clarify the legal status of groups who might wish to bring a challenge on environmental justice grounds (UN ECE, 2002).

Although the UK does not have an EJ movement to compare with that of the USA, interest in the field has grown rapidly in the last 5 years. The discourse on EJ has been led by academics (Dobson, 1998; Walker, 1998; Agyeman, 2000), NGOs (Boardman et al., 1999; SDC, 2002; Adebowale, 2003) and pressure groups (FoE, 2001; Dunion, 2003). These activities have supported the strong policy guidance from the EU, leading government to voice strong support for the principle of EJ, although this has not yet been translated into significant activity at the regional and local levels. A review of this emerging discourse is provided by Agyeman and Evans (2004), who conclude that the links between EJ and sustainability are becoming clearer and more widely understood in the UK, both by government and others.

This understanding has been fostered by empirical studies into the relationship between environmental quality and social distributions. Friends of the Earth (FoE, 2001) conducted the first analysis of this type in the UK as part of their ‘Pollution and Poverty’ campaign, and concluded that the large polluting factories were disproportionately located in poor communities. Many similar studies have followed, including substantive small area national analyses for the Environment Agency in England and Wales (Walker and Mitchell, 2003) and on behalf of a group of Scottish NGO's (Fairburn et al., 2005). Whilst the conception of EJ in the UK is broader than that of the US (e.g. it addresses access to environmental ‘goods’ and fairness in procedural matters), most studies have similarly focussed on environmental pollution, as adequate small area data to support other analysis is generally poorly available. Whilst the evidence base for environmental injustice in the UK remains comparatively weak, a review of past research conducted for government, concludes that “In the UK, environmental injustice is a real and substantive problem…that afflicts many of our most deprived communities and socially excluded groups” (Lucas et al., 2004).

Equity issues addressed in transport have been largely concerned with equity–economy trade-offs, including the relationship between public and private transport, the impact of transport investment on peripheral areas, and the effects of transport investments and policies on specific, underprivileged population groups (Feitelson, 2002). However, transport is also an important determinant on environmental–equity relationships. It produces direct effects such as atmospheric emissions and noise, and also indirect effects, through its influence on the location of polluting facilities and affected people.

Environmental–equity issues have been little studied within a transport context, and to date, point sources have provided the focus for most environmental-equity studies. Cutter (1995) and Bowen (2002) review North American studies, all of which address associations between emissions from industrial facilities and landfills with attributes of nearby populations. Early European studies share this focus, also investigating toxic emissions and landfill sites (Dolk et al., 1998; FoE, 2000, FoE, 2001; Elliott et al., 2001). In the UK, however, several EJ air quality studies, in which transport emissions are a key factor, have also been conducted (see Table 1 and a review in Mitchell and Dorling, 2003).

These studies have all sought to assess the current social distributions of air quality, with little consideration of how these patterns may change in future, or response to policy or plan intervention. Such environmental–equity analysis of alternative transport strategies has been very limited to date. A notable exception is the SPARTACUS project, where a land use–transport interaction model was applied to three European cities, and the impact of different land use and transport policies on exposure of socio-economic groups to transport emissions determined (LT et al., 1998). Forkenbrock and Schweitzer (1999) applied models of pollutant emission (EPA MOBILE5 and PART5) and dispersion (CAL3QHCR) to derive air quality maps for a neighbourhood intersected by a main arterial highway. The air quality and noise maps (the latter modelled using MINNOISE) were superimposed on socio-economic data by census block within a GIS, and the proportion of low-income and minority populations in different exposure bands determined. However, this demonstration project made no attempt to assess the equity impacts of alternative transport policies. For Los Angeles, Bae (1997) evaluated the welfare benefits (health, property value, unemployment risk, etc.) arising from the realisation of federal clean air standards, and concluded that low income and minority groups would benefit disproportionately, and hence that the air quality policy was progressive. However, transport was only addressed indirectly, assumed to be a key factor in achieving the desired air quality standards.

Feitelson (2002) argues that EJ research should not follow past equity studies outside the transport arena, which has simply compared affected areas to unaffected areas, and so failed to produce meaningful and robust results able to guide balancing of the three sustainable development meta-goals. Rather research should introduce the equity dimension into evaluations of exposure to environmental impacts arising from alternative transport policies and plans. This recommendation is consistent with the ‘New Approach to Transport Appraisal’ (NATA) adopted by UK government (DETR, 1998a) and the supporting appraisal guidance (DfT, 2005). The guidance requires an assessment against a series of economic, social and environmental goals, and a number of ‘supporting analyses’, which includes ‘distribution and equity’. This equity analysis is intended to show the distribution of impacts geographically, by transport mode, and by social group. Detailed guidance on how to undertake the distributional analysis is not yet available (although some examples relating to the use of GIS in noise and air quality analysis are given), but the guidance does indicate that environmental equity analysis is an important and developing aspect of UK transport policy and plan appraisal.

To date, all the UK EJ studies (air quality or otherwise) have been cross sectional, identifying current environment–equity relationships. None have a longitudinal component in which the impact of alternative development strategies on environmental equity is assessed, as recommended by Feitelson (2002) and by the NATA guidance. This paper therefore describes the first study in which the environmental equity implications of alternative transport strategies are assessed for a UK city. The strategies investigated are relevant to local government's currently seeking to address problems of urban congestion and pollution.

Section snippets

Assessing the air quality impacts of road transport strategies

In response to the 1996 EU Air Quality Framework Directive (96/62/EC), the UK has developed a National Air Quality Strategy (NAQS) (DETR, 2000) that defines UK policy, tasks and responsibilities for achieving ambient air quality objectives. The focus on air quality, rather than emissions, requires local government's to assess compliance with air quality standards, and usually requires application of dispersion models. Where exceedence of standards for the 2005 target date are forecast, air

Results

Fig. 1 illustrates annual mean NO2 in Leeds for 2005 under the do-nothing option, whilst Table 2 summarises the spatial re-distribution of NO2 in response to the modelled transport scenarios. Clearly redistribution of pollution occurs by location, with some sites experiencing an improvement in air quality, and others a decline. However, further analysis is needed to assess the environmental equity associated with the transport plan options. Two statistical tests were used. Firstly, for each

Transport strategies and environmental equality in Leeds

The analysis shows that there is social inequity in the distribution of NO2 in Leeds, with deprived areas experiencing significantly higher atmospheric concentrations than communities of average or above average affluence. The analysis cannot be used to state categorically that deprived communities bear a greater air quality-dependent health burden, as other factors determining exposure, discussed above, are ignored. Nevertheless, residential pollutant concentration is routinely used as a proxy

Conclusions

This study aimed to determine if environmental inequity occurs with respect to air quality in Leeds, and if so, to what extent strategic transport measures of current interest to local governments might alter this pattern. Inequity in residential NO2 concentration in Leeds does occur, and for the 1993 base year was substantial, and likely to contribute to above average respiratory disease burden in deprived communities. However, the analysis shows that even with no intervention, the observed

Acknowledgements

The air quality data was generated under an EPSRC-DETR funded study, under the LINK Future Integrated Transport programme, with essential support provided by Anil Namdeo, Jim Lockyer, Tony May, David Milne and numerous staff at Leeds City Council. I am also grateful to Danny Dorling for useful discussion, encouragement and comments on an earlier draft of this paper.

References (75)

  • B. Boardman et al.

    Equity and the Environment: Guidelines for Socially just Government

    (1999)
  • W. Bowen

    An analytical review of environmental justice research: what do we really know?

    Environmental Management

    (2002)
  • I. Bracken et al.

    The generation of spatial population distributions from census centroid data

    Environment and Planning A

    (1989)
  • J.S. Brainard et al.

    Modelling environmental equity: access to air quality in Birmingham, UK

    Environment and Planning A

    (2002)
  • R. Bullard

    Dumping on Dixie: Race, Class and Environmental Quality

    (1990)
  • Burningham, K., Thrush, D., 2001. Local environmental concerns in disadvantaged neighbourhoods. Housing, Environment...
  • S.M. Capek

    The environmental justice frame: a conceptual discussion and an application

    Social Problems

    (1993)
  • ADMS-Urban

    (1999)
  • Environmental Justice Policy

    (2002)
  • R.D. Cook et al.

    Applied Regression Including Computing and Graphics

    (1999)
  • S. Cutter

    Race, class and environmental justice

    Progress in Human Geography

    (1995)
  • A New Deal for Transport: Better for Everyone. Department of the Environment, Transport and the Regions

    (1998)
  • Breaking the Logjam: The Government's Consultation Paper on Fighting Traffic Congestion and Pollution through Road User and Workplace Parking Charges. Department of the Environment, Transport and the Regions

    (1998)
  • The Air Quality Strategy for England, Scotland, Wales and Northern Ireland: Working Together for Clean Air. Department of the Environment, Transport and the Regions

    (2000)
  • DfT, 2005. Transport Analysis Guidance. Department of Transport. On line at www.webtag.org.uk. Last updated 5th Jan...
  • A. Dobson

    Justice and the Environment

    (1998)
  • Quantification of the Health Effects of Air Pollution in the United Kingdom. Department of Health Committee on the Medical Effects of Air Pollution

    (1998)
  • K. Dunion

    Troublemakers: The Struggle for Environmental Justice in Scotland

    (2003)
  • H.S. Eggleston et al.

    CORINAIR Working Group on Emission Factors for Calculating 1990 Emissions from Road Traffic

    (1991)
  • P. Elliott et al.

    Birth outcomes and selected cancers in populations living near landfill sites. Report to the Department of Health

    (2001)
  • European Commission

    MEET: Methodology for Calculating Transport Emissions and Energy Consumption

    (1999)
  • Fairburn, J., Walker, G., Smith, G., Mitchell, G., 2005. Investigating environmental justice in scotland: links between...
  • FHA, 2000. Transportation and Environmental Justice Case Studies, Federal Highway Administration Publication...
  • Pollution Injustice

    (2000)
  • Pollution and Poverty—Breaking the Link

    (2001)
  • D.J. Forkenbrock et al.

    Environmental justice in transport planning

    Journal of the American Planning Association

    (1999)
  • A.M. Freeman

    Distribution of environmental quality

  • Cited by (65)

    • Simulation-based analysis of second-best multimodal network capacity

      2022, Transportation Research Part C: Emerging Technologies
    • Support for market-based and command-and-control congestion relief policies in Latin American cities: Effects of mobility, environmental health, and city-level factors

      2021, Transportation Research Part A: Policy and Practice
      Citation Excerpt :

      Stated choice experiments in Jakarta and Nagoya show that being aware of the environmental issues in the city is positively associated with supporting congestion pricing (Sugiarto et al., 2017). Other simulations have identified the environmental benefits of road pricing (Mitchell, 2005; Cipriani et al., 2018). Despite the emerging awareness of these benefits, few studies have connected these health co-benefits with policy acceptance.

    View all citing articles on Scopus
    View full text