Air Quality and Planning 14643 Air Quality and Planning Introduction Air quality may be a material consideration in determining planning applications. The aim of this document is to provide guidance on the way in which air quality and air pollution issues will be dealt with through the planning system. Poor air quality can have detrimental impacts on health and the amenity of users of land in terms of odour, dust and nuisance. The planning system has a key role in protecting people from unacceptable risks to their health and in providing an adequate protection to the amenity value of land. These considerations must, however, be balanced against other aims of the planning system such as to secure economic regeneration and provide adequate levels of housing. The aim is to achieve sustainable development in the borough that achieves the best balance of social, economic and environmental considerations. All of these considerations can have significance for both spatial policy and individual development control decisions. Legislative background Under the Environment Act 1995 and associated regulations all local authorities are required to regularly review and assess air quality in their area against the air quality objectives (AQO’s) in the Air Quality Strategy (AQS). http://www.defra.gov.uk/environment/airquality/strategy/index.htm If the review and assessment exercise indicates that any of the objectives are unlikely to be met by the required date, the local authority must declare an Air Quality Management Area (AQMA) and draw up an action plan outlining how it intends to work towards achieving the objectives. There are currently no AQMA’s in Basingstoke and Deane Borough Council (BDBC). However, the council has identified certain areas of the borough where levels of nitrogen dioxide exceed or are close to the AQO. These are referred to as Local Air Quality Priority Areas (LAQPA). It has not been necessary to declare an AQMA in the borough due to the absence of relevant receptors such as residential properties. Planning The AQS identifies the planning system as one of the key mechanisms for achieving improvements in UK air quality. The land use planning system regulates the development of land, and through determining the location and design of new developments, it can lead to long-term improvements in air quality. Accordingly the land use planning system has a vital role to play to ensure that the objectives of the AQS are met. Guidance with regard to the local planning 1 authority’s air quality responsibilities is outlined in the following regional and national guidance: • RPG 9 Regional Planning Guidance for the South East (2001) • Draft South East Plan- Proposed Changes (October 2008) • PPG 6 ‘Town Centre and Retail Developments’ (1996) • PPS 6 ‘Planning for Town Centres’ (2005) • PPG 13 ‘Transport’ (2001) • PPG 23 ‘Planning and Pollution Control’ (1997) • PPS 23 ‘Planning and Pollution Control’ (2005) • LAQM G4(00), Air Quality and Land Use Planning PPS 23 identifies the relationship that exists between land use planning and the pollution control systems. Whilst PPS 23 advises that local planning authorities should not duplicate the pollution control responsibilities of other bodies, the planning system has an important complementary role to play. In particular through shaping the pattern of development and influencing the location, scale, density and mix of land uses, the planning system can influence air quality significantly. PPG 6 and PPG 13 also address the issue of air quality, through promoting sustainable forms of development, ie focusing development in locations such as town centres that are well served by public transport and thus reducing the need to travel, and the length of journeys made. PPG 13 also emphasises the importance of well designed traffic management as a measure to reduce air pollution (Para 45). What is the purpose of an air quality impact assessment? There are two kinds of impacts that must be considered: • the impact the development will have on air quality, ie a development that increases emissions; and • the impact of existing poor air quality on the development, ie a development that increases exposure. Some developments will cause both types of impact, others will only cause one and some neither. An air quality impact assessment can, therefore, assess: • Site suitability: is an area that is already exceeding AQO’s or has limits close to them suitable for residential development, or could it have a detrimental impact upon its residents? • Impact of development: will the proposed development have a significant impact on air quality? 2 The air quality assessment shall demonstrate the likely changes in air quality as a result of a proposed development and should: • assess the existing air quality in the study area • predict the future air quality without the development • predict the future air quality with the development. When will an air quality impact assessment be required? Policy E1 of the Basingstoke and Deane Adopted Borough Local Plan (1996- 2011) requires, amongst other criteria, that development proposals minimise the potential for pollution of the air. The Town and Country Planning (Environmental Impact Assessment) Regulations 1999 (as amended) requires that certain planning applications are accompanied by an Environmental Statement (ES). For these applications, air quality assessments may form part of the (ES). In addition to this requirement, an air quality assessment would normally be expected for the following types of development proposal: • Those that will result in increased congestion, a change in either traffic volumes, such as a change in annual average daily traffic (AADT) or peak traffic flows of more than ±5% or ±10%, depending on local circumstances, or a change in vehicle speed (of more than ±10 kph), or both, usually on a road with more than 10,000 AADT. This is based on the sensitivity of emission rates to traffic speeds and volumes, and roads below 10,000 AADT normally having a minimal impact on local air quality. • Those that would significantly alter the traffic composition, such as increase the proportion of HGVs in an area, for example, bus stations, HGV parks, increased delivery traffic. • Those that include new car parking, for example, more than 300 spaces or an increase in current parking provision by, for example, 25%, although account should be taken of car park turnover, such as, the difference between short-term and long-term parking, or new coach or lorry parks. • Those that would trigger Basingstoke and Deane Borough Council (BDBC) transport assessment criteria as set out in Appendix B of the Department of Transport guidance. http://www.dft.gov.uk/162259/165237/202657/guidanceontaappendixb 3 • Developments located in, or which may affect, sensitive areas, for example,. ecological sites, or areas of poor air quality (including AQMAs), where either direct emissions to air occur, or where any of the preceding criteria are met. • Introduction of new exposure close to existing sources of air pollutants, for example, road traffic, industrial operations, agricultural operations. • Potential impacts from construction on nearby residents. • Introduction of an industrial activity outlined in the Environmental Permitting (England and Wales) Regulations 2007 that increase emissions in the atmosphere. • Developments that would significantly increase dust emissions in areas where people and/or commercial activities would be exposed. This is not a definitive list and the decision as to whether an assessment is required should be based on the physical characteristics of the proposal and/or the changes in traffic flows. What guidance should be followed:- Air quality assessments should be carried out in line with the National Society for Clean Air (NSCA) document, Development Control: Planning For Air Quality 2006. How detailed should the air quality assessment be? There is no single, definitive method for carrying out a detailed air quality impact assessment, but the method must be appropriate for the development and proportionate to the likely significance of any air quality impact that may be presented. The process to assess the impacts can be divided into four key stages or phases and these are summarised in Table 1. For some developments screening models, such as those set out in the Design Manual for Roads & Bridges, may be acceptable, provided they can be demonstrated to work and are suitable for the urban environment. However, where the screening method predicts that the development may have a significant air quality impact, it will be necessary for a detailed assessment to be carried out. Where a detailed dispersion modelling is required, developers should consult the Environmental Protection team about the proposed modelling technique, to ensure it is appropriate for the air quality assessment. 4 Table 1 – Stages of an air quality impact assessment. Assessment Situation All assessments should include a qualitative Stage 1 : Qualitative risk assessment to identify the likely pollutant risk assessment levels with or without the scheme and the likely nature of exposure, for example, short or long-term with regard to the national objectives. The council has published various reports on air quality and these may provide valuable information. The checklists in LAQM.TG(09) subject to revision, can be used to discount sources. All sources discounted on this basis must be stated. Stage 2: Design manual This is available to be downloaded at for roads and bridges www.airquality.co.uk/archive/laqm/tools.php Its use is accepted for the assessment of transport sources only, where other emission sources are unlikely to make a significant contribution. It cannot be used to assess short- term exposure. All input and output sheets must be included in the report. The authority may request more detailed modelling depending upon the results and/or the complexity of the situation. Road transport models There are various road transport models available. It is vital that the applicant justifies the use of the model prior to its use. Stage 3 - Detailed It may be necessary to use a detailed Dispersion Models dispersion model where there are a number of different emission sources: • where the results from the screening models are close to or higher than the national standards • where the situation is complex • where the authority has already undertaken dispersion modelling to a higher standard to the screening model. 5 Stage 4 - Monitoring Monitoring can be extremely useful in identifying the existing levels and in validating any modelled results. A minimum of three month’s data is required and the data must be corrected to provide a 12 month equivalent to allow for any seasonal variation in air quality levels. Passive diffusion tubes can be used but these should be corrected for bias. Cumulative impact of development Development in urban areas rarely occurs in isolation. Accordingly local authorities should ensure that an air quality assessment for any new development takes into account the cumulative effect of other developments in the area. These should include both committed developments, ie those proposals that have been granted planning permission at the time the assessment is undertaken, as well as other proposals which planning officers consider are likely to proceed. This will ensure that a realistic scenario of air quality in the area is presented for both the ‘baseline’ and the ‘with development’ predictions of the air quality impact of the development. When should the air quality impact assessment be submitted? The air quality assessment must be submitted through the planning department ideally before a planning application is submitted or at the very latest, with the planning application. Assessing an air quality assessment Once an air quality assessment has been received, it is reviewed. The council will review whether the assessment report contains all the information required, if an appropriate assessment has been undertaken and if the conclusions are consistent with the assessment results. Where relevant expertise is not available within the council, an external peer review may be needed. The council, as the planning authority, is then informed of the significance of the air quality effects of the development and recommendations on their acceptability and the level of mitigation needed are made. Assessing the significance of impacts It is important for the local planning authority to be able to assess the significance of any air quality issue presented by a particular proposed development to enable proper consideration to be given to this issue during the decision making process. There is no simple method for making this determination which covers 6 all situations that may arise. The local authority intends to use the methodology developed by the National Society for Clean Air (NSCA) in their publication ‘Development Control: Planning for Air Quality’ in assessing significance. The significance of impacts is assessed using a series of closed questions in a flow-chart which is shown in Figure 1. The impact significance from the flow- chart is then linked to recommendations in Table 2. It is important to note that the process is repetitive and that ultimately the decision making will depend upon the extent to which a developer is able to design out or mitigate the air quality issues. Where air quality is likely to be of at least a medium priority significance, to avoid delays to the determination of a planning application, pre-application discussions are essential. 7 Figure 1 Steps for local authority to assess the significance of air quality impacts of a development proposal Effect of development Outcome DO Assemble the air quality THEY: Lead to a breach or impacts (from Air Quality significant(1) worsening of a Assessment) YES AQ an overriding breach of an EU Limit Value? This could include introduction consideration of new exposure to cause a breach NO Lead to a breach or significant(1) YES AQ a high priority worsening of a breach of an AQ Objective, or cause a new AQMA consideration to be declared(2)? NO Interfere significantly(1) with or YES AQ a high priority prevent the implementation of consideration actions within an AQ action plan? NO NO Interfere significantly(1) with the YES AQ a medium priority implementation of a local AQ consideration Strategy NO Lead to a significant(1) increase YES AQ a medium priority in emissions, degradation in air quality or increase in exposure, consideration below the level of a breach of an AQ Objective? NO AQ a low priority consideration NO Request additional mitigation YES Are mitigation measures, Reach decision where required, adequate? Notes: (1) Where the term significant is used, it will be based on the professional judgement of the Local Authority Officer. (2) This could include the expansion of an existing AQMA or introduction of new exposure to cause a new AQMA to be declared 8 Table 2 Significance Action necessary by developer Outcome Overriding Developer must normally redesign or Normally refuse where this is not possible, introduce where impact measures to mitigate the impact of poor remains overriding air quality. High Developer normally must redesign. May refuse where Where this is not possible measures to the impact remains mitigate the impact of poor air quality high should be included. Measures to offset any air quality issues should be included Medium Developer should redesign if possible or May refuse if develop measures to mitigate the effects additional of the deterioration in air quality as far as measures have not possible. Inclusion of measures to offset reasonably been any air quality issues should be included. included Low Developer may redesign or mitigate any Application would impacts. proceed as normal What measures can be taken to reduce the air quality impact to an acceptable level? Developers are encouraged to formulate proposals which will minimise additional air pollution and preserve or enhance the existing air quality in the borough to provide the highest quality environment for people to live and work. Where a development is deemed to have a significant impact on air quality the local authority will make recommendations based on the assessment results. It is not the case that all developments where air quality is a significant consideration, are refused planning permission. Instead the local authority will require the developer to demonstrate that they have taken air quality issues into account and work closely with the developer to ensure that the development has a beneficial impact on the environment. In doing so a hierarchy of control should be followed: Redesign Mitigate Offset 9 Where redesign cannot reasonably reduce the significance of the air quality issue, it may be acceptable to include measures to mitigate, as far as possible, air quality issues that arise. These measures should not be considered as an alternative option to fundamental redesign but as a fall-back position. Mitigation will still result in a significant air quality impact remaining, therefore, additional measures to offset the potential consequence of a development should also be considered. Where it is not possible to design out any air quality impacts, mitigation and offsetting measures proposed will influence the ultimate planning decision. The decision will balance the residual significance against any other economic, social or environmental objectives of the local planning authority. The council accepts that in some cases it may not be possible, or desirable, to redesign a scheme for new sensitive development to reduce the air quality impacts to a moderate or low significance. This is particularly likely to be the case with small infill developments, where existing sensitive uses are immediate to neighbours and the development is in no worse a position than the neighbouring uses. In these cases the focus may be on mitigation and offsetting. However, mitigation based on sealed and artificially ventilated building designs are not considered a desirable option and will only be accepted as a last resort. Where future occupants might be exposed to high levels of air pollution it is expected that the applicants will design acceptable solutions by considering in particular, site and internal layout. The aim should be to ensure that sensitive façades are a suitable distance from pollution sources such as busy roads. For mixed-use sites, generally sensitive uses should be placed in the least polluted parts of the site. This may result in sensitive uses being located at greater horizontal or vertical distances from busy roads. For such sites the council is unlikely to support residential developments that rely on artificially ventilated and sealed buildings to protect the occupants. This is because sealed residential buildings that cannot be naturally ventilated are not desirable or sustainable. Any proposed engineering measures, must be presented at the application stage as a sufficiently mature design to allow the council to assess its adequacy. Appendix 2 sets out some principles of good design and measures that can be used to mitigate and offset against air quality impacts. The list is not comprehensive and developers are encouraged to explore innovative measures. Planning conditions and Section 106 Agreements. Any agreed design, mitigation and offsetting measures will be secured through planning conditions and/or Section 106 planning obligations. Section 106 agreements can also be secured to require the developer to provide appropriate 10 funds for any reasonable measure that can help the local authority improve air quality. What will happen if the air quality impact cannot be reduced to an acceptable level? In the event that mitigation cannot resolve all air quality concerns, the council will decide whether any remaining adverse effects are sufficiently outweighed by the social, economic or other benefits of the development to the area. In doing this, it will consider national, regional and local development and environmental policies and priorities as set out in planning policy guidance, regional planning guidance, and any relevant supplementary planning guidance. Where can I find more information? Area Relevant Information Planning policy Forward Planning team Tel. 01256 844844 Email: LDF@basingstoke.gov.uk Development Control Development Control team Tel. 01256 844844 Email: firstname.lastname@example.org Air quality Environmental Protection team Tel: 01256 844844 Email: email@example.com. 11 Appendix 1: Reporting requirements for air quality assessment. Requirement Description Introduction/scope This should state why the assessment is being carried out and provide details of the proposed development, a description and map of the site. Qualitative risk This should set out the pollutants tand the sources of emissions to assessment be assessed, the location of receptors or the area for contour modelling to be used, the assessment year(s) and the values against which the results will be assessed. Ambient/background The national emissions inventory allows background emissions to levels be downloaded on a 1km grid square via: http://www.naei.org.uk/index.php These, however, tend to be higher than locally monitored concentrations. The applicant must state clearly which values have been used. Care should also be taken to avoid any element of double counting, ie the inclusion of the background level. Model description The choice of model should be justified and a description given. Models that could be used include: - AAQuIRE - ADMS-Urban - CALINE - INDIC AirViro - PAL Meteorological data Meteorological data should be taken from an appropriate site (within a reasonable distance of the area to be modelled, and within similar topography),At least one year of hourly sequential data should be used. The developer should agree in advance with the Environmental Protection team whether, ’typical’ or ’worst case’ meteorological data are to be used. Emission sources The assessment must consider all relevant emission sources. This must include any approved developments yet to be built, which have the potential to either affect ambient air quality levels or to introduce sensitive receptor types. Any cumulative impact must be considered. Traffic data Detail traffic data to be used, including how and when collected. Industrial Sources Any assessment of a new industrial site under the planning regime must clearly state the operating conditions that have been assumed for example, fuel types and loading and state whether building wake algorithms have been used1 The modelled area The grid size used within the model must be clearly stated. This should typically be in the region of 5 to 10m next to roads. Relevant sensitive receptors should be identified and agreed with the Environmental Protection team. NOx to NO2 The conversion methodology can affect the results due to the Conversion uncertainty over the percentage of primary NO2 and the effect of ozone. Despite these limitations, the approach detailed in LAQM.TG(03) is still appropriate (as amended by the January 2006 update) http://www.uwe.ac.uk/aqm/review/NOx_NO2_Report_27_03_07.pdf. The limitations of the conversion methodology should be fully accounted for within the reporting. PM10 Any PM10 modelling study should present results as a gravimetric equivalent and include secondary and coarse components. Assessment of The key concern with regard to assessing air quality is its impact on impacts human health. The assessment shall consider whether the development will create new areas of exposure. The report must clearly state in tabular form the predicted levels at the receptors with and without development scenarios. This should allow easy comparison between the scenarios and concentrations to be stated. The findings of the assessment must take account of any uncertainties and the level of these must be clearly stated. Any correction values used, for example, year conversions must be stated. Validation It is important to validate the results to identify the degree of modelling uncertainty, which should be applied to the results. The developer should agree with the Environmental Protection team the evidence of model performance to be provided, for example, previous studies or new site specific validation exercise. The developer must demonstrate the model’s effectiveness at predicting statistics relevant to the air quality objectives. Model verification and adjustment should be carried out in accordance with the guidance in LAQM.TG(03) taking local monitoring data into account. Audit trail The assessment must provide a transparent account of the modelling undertaken and all assumptions made. 1 It should be noted that this is not an exhaustive list but is intended as a guide, other factors may arise during discussion with the Environmental Protection team which will require consideration. 1 It is strongly recommended that the advice of the relevant permitting authority is sought where appropriate. Appendix 2 – Examples of good design, mitigation and offsetting measures Polluting development Design • Increasing the distance between any significant pollution source and existing sensitive uses. • For larger or mixed use sites, arrange site layout to ensure sensitive and polluting development is adequately separated. • Ensure that the development design allows for the effective dispersion of pollutants. • Ensure high emission sources are not compromised by tall sensitive buildings. • For large developments carefully consider the best location for car parks and busy access roads. • Ensure car park control systems minimise queuing in entry or exit and car parks have well designed circulation patterns. • In mixed use schemes consider provision of car free areas. • Design commercial or industrial premises to allow for 24 hour servicing. • Consider the impact of the development on the wider road network. Mitigation • Positively encourage the use of public transport and low emission transport and commit to monitoring air pollution through a transport management strategy, for example. green travel plan. • Minimise the need for travel. Offsetting • Provide a contribution to allow improvements in traffic management systems to reduce congestion, such as re-routing traffic. • Provide a contribution to allow changes in road design, e.g. increasing kerb width, one way systems, changed speed limits and improved signing • Provide a contribution to allow development of improved public transport, and facilities to encourage cycling and walking. Sensitive development Redesign of scheme Factors to consider here include: • Increasing the distance between the development façade and the pollution source. • For larger or mixed use sites, arrange site layout to ensure sensitive development is not within the areas of poorest air quality. • Place sensitive uses at higher storeys only. There is no precise way of determining for any development site what an acceptable height is, a precautionary approach should be taken. It is important to ensure that uses at lower storeys are compatible with sensitive uses. • Internal arrangement to position non-habitable rooms on polluted façades. • Avoid features encouraging residents to spend significant periods of time in polluted external environments, for example, balconies. • Where integral car parks are proposed sufficient distance must exist between residential uses and ventilation systems. This may require detailed assessment. • Provision of car free areas. Mitigation In some cases, fixed (unopenable) glazing with system for suitable artificial ventilation. Development that relies upon these measures is undesirable and will only be accepted as a last resort. Suitable ventilation systems will need to: • take air from a clean location • be designed to minimise energy usage • be sufficient to prevent summer overheating • have robust arrangements for maintenance • be designed to ensure satisfactory internal acoustics and prevent loss of amenity to neighbouring uses • avoid providing external doors opening directly into habitable rooms on polluted façade. Offsetting • Providing on and off-site measures to encourage and facilitate cycling, including well designed, secure cycle stores and improved cycle routes. • Provide a contribution to improve bus services, bus stops or facilities. • Provide a contribution to allow new or improved traffic management measures, for example, improved signalling and signing. • Commit to establishing and funding car club. • Provide a contribution to allow footways to be widened. Reference and Guidance Notes • NSCA - Development Control: Planning for Air Quality (Guidance from NSCA on dealing with air quality concerns within the development control process) NSCA 2006. • The Air Quality Strategy for England, Scotland, Wales and Northern Ireland 2007. • Circular 11/95 Use of conditions in planning permission. ODPM. 1995. • LAQM.PG (03) Policy Guidance (code PB7516), Defra 2003. • LAQM.TG (03) Technical Guidance (code PB7514), Defra 2003. • Town & Country Planning [Environmental Impact Assessments] England & Wales Regulations 1999. • PPG4 Industrial and Commercial Development and Small Firms (ISBN 0 11 752723 8), DOE 1992. • PPS6: Planning for Town Centres (March 2005). • RPG9 Regional Planning Guidance for the South East (2001). • Draft South East Plan. • PPS11: Regional Spatial Strategies (September 2004). • PPS12: Local Spatial Planning – (June 2008). • PPG13 Transport (April 2001). • Planning Obligations Circular 05/2005, ODPM 2005. • PPS23 Planning and Pollution Control (ISBN 0117539317), ODPM 2004. • Basingstoke and Deane Borough Adopted Local Plan (1996-2011). Sources of Further Information Basingstoke and Deane Borough Council website http://www.basingstoke.gov.uk this provides links to: • current information on air quality in the borough • Location of existing prescribed processes DEFRA website, http://www.defra.gov.uk contains information on air quality and prescribed processes. University of West of England http://www.uwe.ac.uk/aqm/review/guidance_05.html links to information on air quality and planning. UK Air Quality Archive, http://www.airquality.co.uk/archive/laqm/tools.php.. links to tools to assist consultants with Air Quality Impact assessments. Planning Portal, http://www.planningportal.gov.uk links to advice on planning legislation and policy.