Further observations on air quality relating to the Canterbury District Local Plan resulting from the recent judgement by the High Court inClientEarth (No.2) v Secretary of State for the Environment, Food and Rural Affairs [2016] EWHC 2740 (Admin)

  1. The recent (2/11/16) High Court ruling in Client Earth versus Secretary of State for Environment, Food and Rural Affairs,stated that the current standards and plans for managing air pollution are inadequate.The judge concluded that current emissions models use over-optimistic pollution modelling based on flawed lab tests of diesel vehicles rather than actual emissions on the road. He also argued that current plans for tackling air pollution issued by DEFRA in 2015 place insufficient urgency on tackling breaches of the Air Quality Directive 2008/50/EC and that new plans are needed to ensure compliance as soon as possible.
  1. While the Environment Act 1995 requires the Secretary of State to comply with EU air quality limits, the responsibility for monitoring and addressing air quality issues lies with local councils. Since 1997 Councils have had the duty to review and monitor air quality, declare Air Quality Management Areas (AQMAs) where national limits are breached and develop Air Quality Action Plans (AQAPs) to ensure local air quality complies with National Directives. This role of local councils is made clear in a letter from DEFRA to council leaders, chief executives and Directors of Public Health dated 14th November 2016.
  1. This ruling has two important implications for the assessment of the proposed Canterbury Local District Plan (CDLP):
  • the impact of revised emissions guidance on future estimates of vehicle emissions
  • the need to ensure that air quality in Canterbury complies with the Air Quality Directive 2008/50/EC as soon as possible.
  1. These two factors are significant when set against:
  • current breaches of national limits for NO2and ozone
  • non-compliance of the AQMA
  • the lack of any current AQAP
  • lack of any estimates of the cumulative impact of development on air quality
  • reference in the CDLP Sustainability Assessment that the Plan will have a detrimental effect on air quality

As a result, the current plan cannot comply with the National Planning Policy Framework (NPPF - para 124) and is therefore unsound.

  1. This paper sets out the current context of air quality in Canterbury, details the key relevance of the High Court ruling to the proposed CDLP. The first section highlights current breaches of the Air Quality Directive and briefly outlines the key health implications of vehicle emissions on health. The next section briefly sets out the arguments relating to problems in assessing the impact of planned developments set out in the CDLP on air quality. There then follows a discussion of whether the proposed CDLP adequately addresses air quality implications in the light of the High Court ruling on the need to ensure compliance with the Air Quality Directive as soon as possible. Finally an assessment is provided of the implications of the Court’s ruling relevant to the following CDLP proposed policies:

T1 - a. Controlling the level and environmental impact of vehicular traffic including air quality

CC1 - In considering such proposals, the Council will give significant weight to their environmental, community and economic benefits, alongside consideration of public health and safety and impacts on biodiversity, air quality, landscape character, the historic environment and residential amenity of the surrounding area

DBE 3 - The proposed development does not have a detrimental effect on the highway network in terms of congestion, road safety and air quality

QL11 - Development that could directly or indirectly result in material additional air

pollutants and worsening levels of air quality within the area surrounding the development site will not be permitted unless acceptable measures have been taken as part of the proposal.

Current breaches of air quality standards in Canterbury

  1. Air quality in Canterbury remains of significant concern with continuing breaches of NO2(annual mean of 40µg/m3) and ozone limits (10 annual occurrences of 100µg/m3 8-hour average). There is no current roadside monitoring of PM2.5and PM10 levels in the city and only background monitoring of PM10.Up until 2016, NO2 was measured at three roadside automatic monitors in the AQMA, one background monitorand several diffusion tubes. Two roadside monitors were decommissioned in 2016 including one recording levels of NO2 in excess of national limits. What is clear from the hourly monitoring of NO2is the significant contribution that traffic makes to both the overall levels of NO2 and the variation in levels during the day and the cumulative increases over the period of a week.
  1. Ratified data for NO2is available for the yearsup until the end of 2015 from diffusion tubes which are located in a number of areas in the city. The data showed that NO2 levels in some areas did not comply with national limits. Unratified data for diffusion tubes from 2016 also suggests continuing non-compliancein a number of areas within the AQMA.In particular, air quality in Wincheap and along sections of the A2050 and A28 breach limits set by the Air Quality Directive 2008/50/EC. These lie within the current AQMA which covers these roads within the city.
  1. There have been 17 breaches of UK ozone limits in 2016 recorded at the background monitoring site at Chaucer School. The UK limit was established by DEFRA in 2005 and is a measurement exceeding 100µg/m3 average over an eight-hour period with only 10 exceedances allowed in oneyear. This follows 11 recorded breaches in 2015. Nationally, Canterbury was one of 10 local Councils reported by DEFRA as having Measured Exceedances of the Ozone Information Threshold Value in 2015 of the 1-hour maximum threshold when a level of 185µg/m3 was recorded.
  1. Vehicle emissions are a major contributor to ground level ozone as it is formed from NOx, CO,SO and other volatile organic compounds (VOCs). The increase in ozone levels possibly indicates that while NO2 levels - as measured at different locations within the city - do not always breach upper limits, there may be a cumulative effect due to geography or other factors that is having an impact on ozone levels.
  1. With exceedances of both NO2 and ozone limits, the local AQMA does not comply with the Air Quality Directive 2008/50/EC. In such circumstances the local authority is legally required to have an AQAP. In Canterbury, the AQAP was produced in 2009,but this only covered the initial small AQMA1 area. With continuing breaches of air quality limits the AQMA was extended to cover a much larger area of the city and, despite the duty to have anAQAP in place, one does not exist for the revised AQMA2. Nor is there a current AQAPbeing developed as a result of the DEFRA plan which was published in December 2015 following the Supreme Court ruling that year.Consequently, there is no AQAP which sets outhow the Council will ensure compliance with the Air Quality Directive nor examines the impact of the proposed CDLP.
  1. National Planning Guidance highlights the importance of addressing air quality issues ( It states (Para 002):

Local Planscan affect air quality in a number of ways, including through what development is proposed and where, and the encouragement given to sustainable transport. Therefore in plan making, it is important to take into accountair quality management areasand other areas where there could be specific requirements or limitations on new development because of air quality. Air quality is a consideration in Strategic Environmental Assessment andappraisal can be used to shape an appropriate strategy, including through establishing the ‘baseline’, appropriate objectives for the assessment of impact and proposed monitoring.

Drawing on the review of air quality carried out for the local air quality management regime, the Local Plan may need to consider:

  • the potential cumulative impact of a number of smaller developments on air quality as well as the effect of more substantial developments;
  • the impact of point sources of air pollution (pollution that originates from one place); and,
  • ways in which new development would be appropriate in locationswhere air quality is or likely to be a concern and not give rise to unacceptable risks from pollution. This could be through, for example, identifying measures for offsetting the impact on air quality arising from new development including supporting measures in an air quality action plan or low emissions strategy where applicable.
  1. Poor air quality has a major detrimental effect on peoples’health and within Canterbury leads to over 100 premature deaths every year and over 1000 years of life lost. Poor air quality is associated with increases in asthma and other respiratory diseases, cardiovascular disease and recent research has linked pollution to diabetes and cancer. Children are particularly affected by pollutants such as vehicle emissions and childrens’ lungs sustain lifelong damage from levels of NO2 of 10µg/m3 – levels regularly found on all major roads within Canterbury. Nationally poor air quality is responsible for over 40,000 premature deaths every year and represents a significant financial burden to society and to the NHS.
  1. Recent NICE guidance highlights the enormous societal cost and catastrophic impact of poor air quality, and vehicle emissions in particular, on peoples’ health. The draft guidance issued by NICE ( specifically refers to the role of planning to limit and control vehicle emissions. NICE highlight that where air quality does not meet national guidelines “… those at particular risk (this includes children aged 14 and under, older people aged 65 and older, pregnant women and people with pre-existing respiratory or heart problems).”

Current emissions modelling underestimates actual future emissions

  1. The High Court ruling has relevance to any current and future air quality modelling undertaken within the city – including that associated with current developments in Thanington and South Canterbury. The ruling supports earlier argument that emissions modelling has insufficiently taken into consideration the impact of developments and their resultant increase in traffic on air quality in the AQMA and Canterbury more generally due to utilising outdated emissions guidance.
  1. Modelling by developersin all current and approved planning applications has been based on laboratory emission data as set out in DEFRA guidance from 2009 and is based on versions of theEmissions Factor Toolkit prior to August 2016 (up to version EFT v.6.0.2). The 2015 Action Plan produced by DEFRA relied substantially on modelling using version 6.0.2. The judge was clear in his ruling that this modelling underestimated the actual level of emissions. He referred in particular to evidence by Dr Claire Holman from the Institute of Air Quality Managementwho explained how EU regulations have set "… progressively more stringent emission limits for NOx" 2… but that the "… imposition of Euro standards have failed to deliver reductions in NOx emissions from diesel vehicles in real-world driving conditions in the last 20 years." While Euro 6 standard for cars "… became mandatory for new models from September 2014 and for all new vehicles for September 2015 ". Dr Holman argued that"… the emission limit is currently based purely on laboratory testing. Various real-world tests carried out on Euro 6 cars have shown that they exceed the emission limit by a very large margin."(extract from para 76: ClientEarth v Secretary of State for the Environment Food and Rural Affairs, Judgement 2/11/2016)
  1. Justice Garnham noted that “it is apparent that DEFRA recognised that they [the Government] were adopting an optimistic forecast as a foundation of their modelling.” (Para 83). This view is reinforced by the release of revised emission factors guidance by DEFRA in August 2016.
  1. In his ruling Justice Garnham dismissed the Government’s argument that the COPERT modelling underpinning the 2015 Air Quality Action Plan was “widely used”. He argued that this was an insufficient defence given that it has been recognised for some time that the data on Euro 6 vehicle emissions was incorrect (see for example House of CommonsEnvironmental Audit Committee2014), the issuing of revised guidance on calculating emissions by DEFRA (August 2016) and the Highways Agency in 2015 (IAN 185/15).
  1. Following concerns raised about the accuracy of vehicle emissions data DEFRA released interim emissions factors guidance in August (v7.0.1)and in September Emisia SA1 published new COPERT guidance.
  1. The COPERT 5 v1.0 and COPERT 4 v11.4 calculation of emissions guidance issued by Emisia SA contains a new set of Euro 6 NOx emissions factors (EFs) for passenger cars and light commercial vehicles (LCVs) and updated NOx emission factors for Euro 5 LCVs. These are based on latest emission information collected by the European Research on Mobile Emission Sources (ERMES) parties and by individual European Member States. This is an interim set of EFs aim at reflecting average measured levels so far and represent the best estimate of future technology progress.
  1. These new EFs lead to almost twice as high levels for Euro 6 diesel NOx for vehicles put in to circulation until 2016 compared to our previous estimates.With the transitional introduction of Euro 6 Real Drive Emissions (RDE) regulation, diesel emission levels are considered to further improve in time. Additional data are being collected in the EU that will help establish the rate of improvement. Based on these, a more refined dataset is prepared to be included in the 2017 version of COPERT 5 but the current assessment is that it should not substantially differ from the 2016 interim one.
  1. Final confirmed details will only become available when DEFRA releases a revised Emission Factor Toolkit and associated Emissions Factors Toolkit v7.0User Guide currently dated August 2016.
  1. It is clear from this new EmisiaSA guidance and the High Court judgement that any modelling for emissions impacts needs to take account of higher levels of emissions in line with emerging EF guidance. Any submissionsbased on laboratory Euro 6 data does not provide accurate emissions forecasts. Thus,where planning permission has recently been granted or is under consideration in Canterbury developers will have underestimated future levels of NO2 and particulate matter in any air quality modelling. Inaddition,any particulate matter modelling is based on assumptions rather than actual data as roadside PM2.5 and PM10 are not measured in Canterbury, although levels would be related to NOx levels. Therefore, current analysessubmitted in support of planning applicationsand, if undertaken, for the CDLP Sustainability Assessment, underestimate future estimates of pollution levels and thus cannot be accepted as they stand.
  1. There will also be additional cumulative increases in emissions from traffic generated by other proposed developments allocated within the proposed CDLP and from other additional sites allocated for housing and commercial development that are not noted in the Plan. It is clear from planning guidance and the NPPF that these are relevant considerations in ensuring a sound district plan.
  1. Current estimates from Kent County Council modelling and those submitted by developers in recent applications all show increasing traffic volumes which will have a detrimental effect on air quality by increasing vehicle emission levels. Modelled traffic levels and estimates of modal shift from cars to cycling, public transport use and walking have been challenged as underestimating traffic increases and over estimating modal shift. Irrespective of the actual increase,the new and emerging emissions guidance means that any traffic increase will lead to further deterioration in air quality and continued breaches of national limits in the AQMA with a consequent impact on peoples’ health.

Impact on achieving compliance with the Air Quality Directive 2008/50/EC

  1. I argued in my original submission to the District Plan Inquiry that the Council has a duty to ensure that statutory limits for air quality are met as set out in the 2015 DEFRA national Air Quality Action Plan. In accordance with the NPPF para 124 “Planning policies should sustain compliance with and contribute towards EU limit values or national objectives for pollutants, taking into account the presence of Air Quality Management Areas and the cumulative impacts on air quality from individual sites in local areas. Planning decisions should ensure that any new development in Air Quality Management Areas is consistent with the local air quality action plan.”The recent High Court judgement has significant relevance to this in relation to Canterbury’s proposedCDLP as it places a further requirement to ensure compliance with the Air Quality Directive as quickly as possible.
  1. I argued thatwhile the air quality policy in the Local Plan (QL11) was welcome, the City Council had not demonstrated how it will ensure improved air quality. Reference is made to the AQAP (Para 12.46) but this was drawn up in 2009 and requires revision to cover the whole AQMA and especially in the light of the South East (zone 0031) section of the national Air Quality Plan. The absence of a current AQAP is a serious omission in relation to whether the proposed CDLP can be approved.
  1. TheHigh Court ruling places greater emphasis on achieving compliance with air quality limits as soon as possible. Justice Garnham noted that:

“It is plain from the words of the Article that the Member State is obliged to ensure that the plans are devised in such a way as to meet the limit value in the shortest possible time” (Para 47)