Transport CommitteeWritten evidence from the London Borough of Hillingdon (AS 16)
Introduction
Thank you for the opportunity to participate in this Inquiry. I am submitting this evidence on behalf of the London Borough of Hillingdon. I have been the Leader of the London Borough of Hillingdon since 2000 and am a local councillor for the Ickenham Ward. I am one of the key partners of the 2M Group, an all-party alliance of local authorities concerned about the environmental impact of Heathrow operations on their communities. The Group, which took its name from the 2 million residents of the original 12 authorities, now represents a combined population of 5 million people and was successful in 2010 in overturning plans for a third runway at the airport. The Group is not anti-Heathrow but works together to improve the environment and protect the quality of life for local people.
My response is set below in an Executive Summary and under the specific questions that the Committee has agreed to pursue.
Executive Summary
The main points and key recommendation for action by the Government or others which I would like the Committee to consider for inclusion in its report to the House are as follows:
Main Points
a)
b)
c)
d)
e)
f)
g)
h)
i)
Key recommendation
I would ask the Committee to recognise that a third short runway at Heathrow is not likely to be sufficient in the long term and there will inevitably be pressure for a 4th runway. There is insufficient land for Heathrow Airport to expand to meet the long term requirements of a hub airport. To attempt to propose airport expansion in such an already congested location, with the devastating impacts arising from the demolition of homes and the loss of communities and the unacceptable levels of noise and air pollution that this would be bring to large areas of London, is not logical or rational in any future aviation policy.
Question 1—What should be the objectives of Government policy on aviation?
a.
1. The Government’s draft Aviation Policy Framework consultation states that international aviation connectivity is important to the UK. It follows, therefore, that the aviation industry has a role to play in ensuring that the UK remains a well connected nation. However, the question itself asks whether international connectivity is important to the UK aviation industry.
2. Our experience at Heathrow doesn’t allow the conclusion to be drawn that international connectivity is necessarily important to the aviation industry. Increases in capacity have not been synonymous with the provision of increases in connectivity.
3. When permission was given for the building of Terminal 5, it included a capacity increase up to 480,000 Air Transport Movements a year. Despite the increase in flight numbers, over time there has been a decline in destination choice with airlines simply operating more profitable routes at a higher frequency. The number of destinations served has dropped from 227 in 1990 to 180 today, despite the permitted increase in capacity. (page 24, All Party Parliamentary Group Inquiry into Aviation Policy and Air Passenger Duty (APPG Report), August 2012).
4. Maintaining diverse international connectivity for the UK has therefore been sacrificed for frequency on the same profitable routes. As this experience indicates, maintaining connectivity cannot be left to the airlines. This aspect is highlighted in the APPG report:
“airlines cannot be expected to substitute established and successful routes which provide an economic return for unproven new routes.” (page 24)
5. Given this statement, if diverse international connectivity is vital to the UK economy, there do not appear to be the appropriate Government interventions available to ensure that airlines play their part in maintaining and increasing international connectivity, nor any means of ensuring consolidation where slots are being used uneconomically and to the detriment of the UK’s international connectivity. There is no evidence to suggest that the repeated calls for capacity increases are a guarantee of better international connectivity. This is especially relevant at congested airports such as Heathrow.
b.
6. I have not focussed on this question.
c.
7. I have not focussed on this question.
d.
8. Whilst the provision of a good passenger experience is an important aspect for UK business, and its reputation internationally, sufficient weight needs to be given to protecting the needs of the local communities in close proximity to large airports.
9. Whilst the provision of jobs to local communities is a positive aspect of close proximity to an airport, the negative impacts such as increased pollution; increased noise; transport congestion on road networks; and over-crowded public transport can outweigh any benefits.
10. The Government has a duty to protect the health and well being of local communities, as well as having a legal obligation to comply with relevant European environmental legislation on issues such as local air quality. This needs to be reflected, and given sufficient weight, in any future aviation strategy. This aspect must not be sacrificed by simply putting in measures and policies to prioritise improving the passenger experience.
e.
11. At present, aviation doesn’t fit in the overall transport strategy. This is something that needs to be addressed urgently. Aviation must form part of an overall strategic national integrated transport infrastructure framework that encompasses airports, roads and rail, including any potential high speed rail.
12. As an example, decisions on High Speed 2 (HS2) have already been made for a preferred westerly route from London to incorporate a spur to Heathrow, described in the HS2 Decision documentation as the country’s major hub airport. This is not aligned to the timescales for the Independent Commission chaired by Sir Howard Davies to look at the requirements for future aviation capacity, including the potential for a new hub airport, which will not report until 2015.
13. Should the Independent Commission Review recommend a new hub airport in a location other than Heathrow, then the HS2 route and appropriate links would need complete re-assessment because it would not need to go west from London in order to link with Heathrow airport. If the Government is determined to postpone the decision on airports until post 2015, it should also call a halt on the proposal for HS2 as it currently stands and align the two strategies accordingly.
Question 2—How should we make the best use of existing aviation capacity?
a.
14. There are airports that are currently not at capacity which could be used to take the pressure off congested airports, such as Heathrow. The Government has suggested extending the fifth freedoms policy to Gatwick, Stansted and Luton. This policy grants rights to allow an airline of one country to land in a different country, pick up passengers and carry them on to a third country. By extending it to include Gatwick, Stansted and Luton, there are likely to be new services attracted to these airports and additional stop-over flights, which would support London’s and the UK’s aviation connectivity and the UK’s economy. The Government has also suggested other measures such as offering bilateral partners unilateral open access to UK airports away from the congested South East airports and reviewing the slot mechanism. I consider such measures are worthy of investigation.
15. The provision of resilience must be built into the operating model of any airport. At Heathrow the number of air transport movements has been set too high, ie at the actual capacity limits of the runways, as opposed to an operational capacity which would allow for the provision of resilience. This is considered to be unacceptable for two reasons. Firstly, appropriate limits on air transport movements at airports would ensure greater resilience and thereby improve the passenger experience in relation to punctuality and delays and also have environmental gains in aspects such as reducing stacking in the air and congestion on-airport. Secondly very high air transport movements has detrimental impacts on the surrounding communities, who have to cope with the extra measures which are put in place by airport operators to cope with congestion and improve resilience.
16. A recent statement from the Mayor of London (speech to Business Leaders, City Hall, 4th Oct 2012) has proposed that any runway utilisation should be at no more than 75% to avoid congestion on the ground, congestion in the air and improve the passenger experience in terms of the airport’s ability to recover from disruption. I would support this view.
b.
17. I have not focussed on this question.
c.
18. Currently different aspects of transport are looked at in isolation, for example, the high speed rail route and link to Heathrow has been given approval, yet the aviation strategy in relation to the potential expansion and location of future hub capacity is currently postponed to post 2015. There must be a strategic national integrated transport infrastructure planning framework. Without such a framework, airport growth will remain constrained by poor transport links to the detriment of the national economy and continue to have adverse social and environmental impacts to the detriment of local communities.
19. In terms of regional access, although an airport will have a clear objective to improve surface access for its passengers and workers, this must be delivered as an integral part of the whole surrounding road and public transport network, to ensure implementation of the best option for the region and local communities.
20. Heathrow airport is situated in a congested part of west London with motorways, local roads and public transport networks, including rail and tube lines serving central London, west London and the Thames Valley Corridor as well as several local borough networks. The development of the airport and its associated surface access infrastructure has been piecemeal. The result is a very congested road and public transport network, with traffic serving a large international airport having to compete with all other transport users. The consequences of a busy international airport in a very densely populated area include both congested road networks, resulting in unacceptable levels of air and noise pollution, and also unsatisfactory public transport, with commuters competing for space with airport passengers and luggage. Whilst further improvements to surface access may be feasible at Heathrow, they are limited given the existing congestion and the density of development in the area.
Question 3—What constraints are there on increasing UK aviation capacity?
a.
21. Where an airport is located in a densely populated area, environmental constraints pose a serious limit on its ability to increase capacity. At Heathrow, both air and noise pollution levels exceed acceptable limits. Where local communities in close proximity to an airport suffer from unacceptable levels of noise and air pollution, benefits in technologies such as quieter aircraft cannot be used as an opportunity to increase flight numbers but must be directed towards improvements in the health and well being of local residents. Due to the constrained nature of the airport location, Heathrow has developed to operate at capacity with no resilience. It is not acceptable to increase the burden on local communities by introducing extra measures to attempt to make an inappropriately located international airport more effective.
22. The wrong location for an international airport becomes its own constraint in terms of future growth. Heathrow is a two runway, segregated mode operation airport with an annual aircraft movement limit of 480,000. Its operation already causes intolerable levels of noise for swathes of Londoners, and, due to its congested urban location, is a main contributor to levels of air and noise pollution above health based standards for surrounding communities. In order to maintain its international hub status, Heathrow will inevitably require 4 runways and therefore continued incremental growth will not be practicable or sustainable in the future.
23. The constraints of noise, air pollution and operational resilience on increasing UK aviation capacity are discussed in more detail below.
i) Noise impacts
24. Heathrow is unique in Europe in terms of the magnitude of the noise impact on the surrounding densely populated area, with thousands of people living on a daily basis with an aircraft overhead every 90 seconds and with flights that disturb sleep from as early as 4:30 am. The levels of air pollution are above those set for the protection of health and the surrounding roads and public transport networks are congested. This has been the case for a number of years and it was these conditions which helped the Coalition Government decide that expansion in this location was not tenable.
“The quality of life impact of a third runway with up to 220,000 more flights over London every year, would be massive and there is no technological solution in sight to ensure planes become quiet enough quickly enough to make this burden in an way tolerable. So we need another solution…” (our emphasis), Theresa Villiers, Transport Times Conference, April 2012
25. Where an airport is located in a densely populated area such as London, its growth will be seriously constrained by the requirement to meet the Government aviation policy objective to reduce and limit those impacted by noise, and, to meet the National Noise Policy Statement for England objective to avoid significant adverse impacts on the health and well being of local communities, becomes a constraint on growth
26. Heathrow Airport accounts for approximately 70% of people in the UK exposed to aircraft noise, and the noise impact from this one airport easily exceeds the combined impact of all the other hub airports in Western Europe. The European Union Noise Directive requires the use of the 55 dB Lden contour which also takes account of the differing impacts at different times of the day, night noise being the most intrusive. The outdated DfT measure of 57dB LAeq16h, uses a higher noise level and is measured as a straight average over a 16hr day. The extent this difference has on the estimation of the impact on local communities is discussed below.
27. The DfT measure (57 dB LAeq16h contour) for Heathrow in 2010 covers an area of 106.3sqkm in which 224,550 people live, the EU Noise Directive criteria (55 dB Lden contour) covers an area of 222.3 sq km in which 712,100 people live. It is totally unacceptable to use out-dated metrics. A more accurate measure of community exposure to noise must be adopted as soon as possible, including recognition that the frequency of flights is an important aspect rather than just the noise of an individual flight, plus accounting properly for different times of the day, especially night noise. I have attached a technical paper which gives evidence to support our view (Appendix A)
b) Local air quality
28. Local air quality is a significant constraint to expansion at Heathrow with levels in the surrounding communities exceeding European health standards. The annual mean nitrogen dioxide standard was required to have been met by 2010. The UK Government Air Quality Plan which was submitted in September 2011 to the European Commission as part of its legal obligations for meeting air quality limits has predicted that this area will not be in compliance with this standard until at least 2020. This would appear to be unacceptable.
29. The previous Government’s proposals for expansion of Heathrow (Adding Capacity at Heathrow, 2008) relied heavily on assumptions that significant improvements in road vehicle technology would create the necessary level of “headroom” in which more flights could be added. This reliance has proved to be misplaced. As the Government Air Quality Plan submission to Europe has reported, limits will not be met, even under present operating conditions, until at least 2020. Given the legal significance of the UK Government being in breach of the legislation to meet European Union limit values for local air quality, this becomes a serious constraint on any future capacity increases in urban locations such as Heathrow.
c) Operating at capacity without resilience
30. Because Heathrow is operating at capacity, the airport has no operational resilience. To allow an airport, which is an uncontrolled source of emissions, to operate at capacity in such an urban location has proven to be a mistake to the detriment of local communities who have suffered as a result.
31. Measures are currently being tested at Heathrow to improve resilience through trials of operational freedoms, but it is the local communities who will again bear the brunt of this with encroachments into much valued respite periods being one of the potential outcomes.
32. I support the Mayor of London’s recent view that maintaining runway utilisation at 75%, as opposed to the 99% at Heathrow, could bring about improvements in congestion on the ground; reduce stacking in the air; and improve the passenger experience in terms of speedier recovery from disruption. Maintaining resilience becomes a constraint in terms of increasing capacity because in order to operate more efficiently, the current levels of air transport movements at Heathrow need to be actually decreased not increased.
b.
33. I have not focussed on this question.
c.
34. I have not focussed on this question.
Question 4—Do we need a step-change in UK aviation capacity? Why?
a.
The requirement for extra capacity
35. Before deciding on the need for a step change in capacity increases, there are a number of questions which require examination. Changes including new technologies such as video-conferencing; substitution of short haul for rail trips; increasing oil prices; and constraints in terms of reducing climate change emissions could all have an impact on the need for, and the magnitude of, any increases in capacity. In addition, the impact of new generation aircraft, such as the Boeing 787, which can potentially provide a point to point service over a greater distance, should be appropriately taken into account.
36. These issues need to be understood before any decisions are made on the provision of extra capacity or whether the hub model is the correct operating model for increasing capacity and maintaining connectivity.
The objective behind the need for capacity increases
37. If the Government objective is to maintain and improve international connectivity, there needs to be a recognition that extra capacity does not necessarily lead to extra connectivity. This has been proven by experience at Heathrow.
38. Airlines cannot be forced to either provide new routes or maintain existing ones where market forces dictate otherwise. There must be recognition of the risk that increased connectivity is not a guaranteed outcome, especially in situations where airports become quickly constrained, as would be the case of an additional short third runway at Heathrow. This aspect must be taken into account before decisions are made.
Hub location
39. The number of runways and the associated facilities to maintain a hub airport are larger than a traditional point to point airport, due to the nature of the hub operation and the requirement for feeder flights. Unless the hub airport is sited in a suitable location, maintaining its hub operation will become constrained by land availability and environmental issues, which is what has happened at Heathrow.
40. Heathrow is unusual in being a successful hub airport with only two runways and generally other successful hubs have more runways. In comparison, Schiphol has six runways; and Charles de Gaulle and Frankfurt have four. Given the pressure for future expansion to align with the predictions in aviation growth, and the need to connect with emerging markets such as Brazil, Russia, India and China, it is clear that there is growing concern that in order to maintain a successful hub operation, there is a need for more capacity and for additional runways. A third short runway at Heathrow is not likely to be sufficient in the long term and there will inevitably be pressure for a 4th runway.
41. The location of Heathrow Airport has become its own constraint. To attempt to propose airport expansion in such a congested location, with the devastating impacts arising from the demolition of homes and the loss of communities and the unacceptable levels of noise and air pollution that this would be bring to large areas of London, is not logical or rational in any future aviation policy.
42. A hub airport needs to have sufficient capacity to allow for growth in the feeder flights which are needed to maintain the hub model of operation and for it to be operated at a level where there is operational resilience. I support the Mayor of London’s view (Aviation speech, City Hall, 4th Oct 2012) that maintaining runway utilisation at 75% could bring about improvements in congestion on the ground, reduce stacking in the air and improve the passenger experience in regard to speedier recovery from disruption.
43. A hub airport must also be situated in a place which minimises harm to the environment, and, most importantly, people. West London is not somewhere that fits these criteria and a successful hub airport cannot be “shoe-horned” into Heathrow.
44. If the UK requires a first class hub airport for London, then other options for its location must be appraised against the national Aviation Policy Framework, including wider objectives such as the well being and quality of life of local residents.
b.
45. Up to now the main evidence for increasing aviation capacity has been based upon economic gain. I support the draft Aviation Policy Framework approach of achieving a better balance than in the past between the benefits aviation brings and its impacts. The impacts must be accounted for at both a global level, and at a local level in terms of health and wellbeing of communities and the environment.
46. If this objective is taken seriously, it is obvious that increasing capacity at Heathrow is not the answer to increasing UK aviation capacity because this would result in the demolition of hundreds of homes; the loss of communities; increased noise for millions of people; and unacceptable pollution levels above European Union legal standards for health.
APPENDIX A
NEW EVIDENCE ON AIRCRAFT NOISE ANNOYANCE
Introduction
This paper presents evidence that there is a useful correlation between the aircraft noise annoyance studies reported in European Environment Agency (EEA) report 11/2010 and the UK Government’s ANASE study. Both sets of studies have found a significant shift in that aircraft noise now causes annoyance at lower levels than it did previously. The significance of this, in relation to the Draft Aviation Policy Framework consultation, is that it provides some support for the use of the ANASE findings in the development of future aviation policy. This is important, as without this support, the ANASE findings have been set aside. However, until the ANASE issue can be resolved, the conclusion is that the EEA findings should be accepted for the development of future aviation policy, in relation to annoyance. There remains an important caveat to this, in that the EEA evidence itself needs to be improved by including the significance of flight numbers in any noise annoyance assessment. Only once this is resolved can the question of acceptable aviation capacity be addressed fully. So, in spite of the various study deficiencies, the message remains clear, that aircraft noise now causes annoyance at lower levels than it did previously, and this issue must be addressed in any future aviation policy.
EU and UK models for aircraft annoyance
European Environment Agency report 11/2010 [1] is a good practice guide intended to assist policy makers and competent authorities in understanding and fulfilling the requirements of Directive 2002/49/EC [2], commonly referred to as the Environmental Noise Directive, relating to the assessment and management of environmental noise. It summarises the latest European view on issues such as exposure-response relationships and thresholds for health endpoints (annoyance, sleep disturbance, cardiovascular effects and cognitive impairment). Individual annoyance relationships with the noise metric Lden are given for road, rail and aircraft noise.
The EEA report gives a previously used European aircraft noise annoyance relationship based on studies carried out prior to 1990. This is the same relationship as given in the 2002 EU Position Paper [3]. The relationship gives an estimate of the percentage of persons highly annoyed at a given Lden noise exposure. The EEA report mentions studies showing a trend change in annoyance around 1990, and gives an updated European annoyance relationship based on aircraft noise studies carried out after 1990. These were all European studies (Switzerland, Germany, Netherlands) regarded as more appropriate for the EU than the pre-1990 studies, which were mainly carried out in the USA and Australia. Figure 1 gives the results for the pre-1990 and post-1990 studies in terms of percentage highly annoyed in relation to Lden. It can be seen that levels of annoyance at a given noise level are much higher for the post-1990 studies than for the pre-1990 studies. The analysis given in Figure 1 is confined to the range of noise levels in the ANASE study (40.9 to 64.2 dB LAeq,16h).
At 59 dB Lden, for example, the relationship adopted for the pre-1990 studies in Figure 1 gives 16% highly annoyed. In the case of the post-1990 studies, the relationship adopted gives the same percentage highly annoyed at around 49 dB Lden. Thus, the EEA report suggests that levels of annoyance (expressed as percentage highly annoyed) that occurred at 59 dB Lden in the pre-1990 studies occurred at around 49 dB Lden in the post-1990 studies, a reduction of around 10 dB Lden.
The Government’s aviation policy uses 57 dB LAeq,16h as the level of daytime noise marking the approximate onset of significant community annoyance. This level is based on the Aircraft Noise Index Study (ANIS) [4] carried out in the UK in the 1980s. The CAP725 document [5] produced by the Civil Aviation Authority in 2007 outlines methodologies for environmental assessment of an airspace change proposal. It gives an aircraft noise annoyance response relationship for calculating percentage of people highly annoyed using LAeq,16h noise levels. The relationship is based on the Schultz curve produced in 1978 [6]. The document states that the ANIS results exhibit the same general trend as the aircraft studies in the Schultz analysis. The EU annoyance relationships use the Lden noise metric rather than the LAeq,16h noise metric used in the UK. Analysis of data [7,8] relating to Heathrow airport in 2006 shows that Lden is typically around 1.7 dB higher than LAeq,16h. This 1.7 dB adjustment has been used to convert LAeq,16h to Lden to give the CAP725 annoyance relationship shown in Figure 1.
The Attitudes to Noise from Aviation Sources in England (ANASE) study [9] reported in 2007 that annoyance with a given level of aircraft noise is much higher than when the ANIS study was carried out. The ANASE study made a direct comparison with the ANIS study in terms of “mean annoyance” with aircraft noise. This showed that the level of mean annoyance found at 57 dB LAeq,16h in the ANIS study was found in the ANASE study at a level of just over 50 dB LAeq,16h, a reduction of just less than 7 dB LAeq,16h.
The Government accepted that the ANASE study demonstrated that annoyance with a given level of aircraft noise is higher than found in the ANIS study. However, on advice contained in an independent peer review report [10], the Government decided that the detailed findings of the ANASE study should not be relied on.
Most of the analysis in the ANASE report related to “mean annoyance”, and trend lines were fitted to graphs of mean annoyance versus LAeq,16h. Figure 7.2 of the ANASE report gave a graph of percentage “at least very annoyed” versus LAeq,16h, but no trend line was fitted to the plotted data points. In the ANASE study, responses from respondents were recorded using an annoyance scale of (i) “Extremely annoyed”, (ii) “Very annoyed”, (iii) “Moderately annoyed”, (iv) “Slightly annoyed” and (iv) “Not at all annoyed”. The annoyance scale did not include a response of “Highly annoyed” as used in the EEA and CAP725 reports so comparison of the results of the different studies is not straightforward.
However, section 6 of the ANASE peer review report [10] assumes that the ANASE term “at least very annoyed” is equivalent to the term “highly annoyed” used in other studies. This assumption allowed the peer reviewers to deduce (apparently by eye) two trend points for the plotted ANASE data points. The two ANASE trend points given in the peer review report are 8.5% highly annoyed at 47/48 dB LAeq,16h, and around 40% highly annoyed at 57 dB LAeq,16h. These trend points relate to the corrected version of ANASE report Figure 7.2 given in the Erratum dated 1st November 2007 contained in the ANASE final report dated October 2007.
The two ANASE derived trend points are plotted in Figure 1, after converting LAeq,16h to Lden by adding 1.7 dB, derived from Heathrow data for 2006. Using the same assumptions that (i) the ANASE term “at least very annoyed” is equivalent to “highly annoyed” in other studies, and (ii) Lden can be estimated from LAeq,16h by adding 1.7 dB, the results derived for all ANASE sites have been plotted in Figure 1. That figure also shows a third order polynomial trend line fitted to the ANASE derived results. The relatively poor agreement between the plotted data points and the fitted trend line (R2 = 0.67) reflects the spread of the data points, but this is not unusual in social surveys of this kind.
It is important to note that Figure 1 shows that the annoyance levels at a given noise level are much higher for the EEA post-1990 studies than for the EEA pre-1990 studies. For example, percentage highly annoyed at 57 LAeq,16h (approximately equivalent to 58.7 dB Lden) is more than doubled from around 15% for the pre-1990 studies to around 37% for the post-1990 studies. It can be seen from Figure 1 that the annoyance levels for the UK’s CAP725 relationship are generally lower than given by the EEA pre-1990 studies relationship, and much lower than given by the EEA post-1990 studies. This implies that continued use in the UK of the CAP725 annoyance relationship will seriously underestimate levels of aircraft annoyance. The ANASE trend line is generally similar to the EEA post-1990 studies relationship, and certainly in much better agreement with the EEA post-1990 studies relationship than is the CAP725 relationship.
The Government rejected the detailed findings of the ANASE study and continues to rely on the ANIS, Schultz and CAP725 aircraft noise annoyance relationships, even though these relationships are based on social surveys carried out more than 25 years ago. It seems doubtful that these relationships remain in calibration for current public attitudes, flight numbers, aircraft fleet mixes and aircraft noise characteristics. The EEA report supports this doubt on the continued validity of these relationships. This is because the EEA report suggests that levels of annoyance at a given noise level are much higher than suggested by previous European guidance. Furthermore, these EEA findings of much higher levels of annoyance seem to be replicated by the results of the recent ANASE study.
Objectives and findings of the ANASE study
The ANASE study was commissioned by the Government in 2001 in order to update the ANIS study of 1982 which led to LAeq,16h noise index being adopted by the Government for measuring aircraft noise. The ANASE report recognises that the amount of air traffic has increased significantly since 1982 whilst the sound levels generated by individual aircraft events have been significantly reduced as older, noisier aircraft have been replaced by more modern aircraft types with quieter engines and much improved climb performance. It is also recognised that attitudes to aircraft noise may have been changed due for example to the general growth in personal income, higher expectations of a peaceful living environment and less tolerance of environmental intrusion.
The main findings of the ANASE study are reviewed below against the study objectives.
Objective 1: Re-assess attitudes to aircraft noise in England
The study found that the annoyance level of respondents increased as the noise indicator LAeq,16h increased, and that a large proportion of measured variation in annoyance can be accounted for by LAeq,16h. However, for a given LAeq,16h, there is a range of reported annoyance indicating that annoyance is not determined solely by the amount of aircraft noise as measured by LAeq,16h. The main additional influences on the level of annoyance were found to be respondent’s household income and socio-economic group.
The study found that for the same amount of aircraft noise, measured by LAeq,16h, people were more annoyed in 2005 than they were in 1982.
The study showed that people are much more sensitive to aircraft noise at night (particularly around midnight and the early hours thereafter). In contrast, people are least sensitive to aircraft noise in the morning and early afternoon. Ideally, therefore, a noise indicator for aircraft noise should reflect these times of day sensitivities. In contrast, LAeq,16h does not reflect weighting for sensitivities by time of day.
Objective 2: Re-assess their correlation with the LAeq,16h noise index
The study considered whether LAeq,16h is the appropriate measure of aircraft noise for predicting annoyance. The study found that while LAeq,16h continues to be a good proxy for measuring community annoyance at a given point in time, the relationship between LAeq,16h and annoyance is not stable over time. Because of this, use of LAeq,16h to predict future levels of annoyance may be misleading. In particular, where numbers of aircraft are increasing significantly, the ANASE results suggested that under-prediction of annoyance is likely.
The study recognised that the LAeq,16h noise index incorporates a mathematical trade-off of 10 between event noise level and number of noise events1, which means that each doubling or halving of the numbers of aircraft noise events counts as equivalent to a 3 dB increase or decrease in average noise levels2. The results from the study suggested that the LAeq,16h noise indicator gives insufficient weight to aircraft numbers, and a relative weight of 20 appears more supportable from the evidence than the relative weight of 10 inherent in LAeq,16h.
Objective 3: Examine willingness to pay to remove aircraft noise
The study was required to examine (hypothetical) willingness to pay in respect of nuisance from aircraft noise, and whether attitudes might be affected if cash transfers or, for example, noise insulation grants were made available. The study found that aircraft event noise level, aircraft type, time of day and personal characteristics (in particular household income) influence annoyance and willingness to pay.
Aircraft noise action plans
The EEA report 11/2010 [1] provides the dose-effect relationships intended to be used to assess the effects of noise on populations as required by the Directive [2]. Section 6 of the EEA report suggests that the lower noise thresholds for mapping are intended to delimit the area where noise is “considered to be a problem”. These thresholds are noise levels above which health effects start to occur.
The EEA report accepts that use of the current threshold levels for noise mapping of 55 dB Lden and 50 dB Lnight is understandable as a first step because of the large scale noise mapping required. However, the report points out that Member States are free to choose their own noise thresholds from where to start action planning, and the Lden threshold for noise mapping of 55 dB Lden does not take into account differences that exist between different noise sources. These differences are illustrated in Table 6.1 of the EEA report giving respective percentages highly annoyed at 45, 50 and 55 dB Lden for road, rail and aircraft noise. Table 6.1 of the EEA report is reproduced here (in part) as Table 1.
Table 1
TRANSPORTATION NOISE ANNOYANCE
(REPRODUCED FROM EEA REPORT)
|
Percentages of highly annoyed |
|||
|
Lden |
Road |
Rail |
Aircraft |
|
55 dB |
6% |
4% |
27% |
|
50 dB |
4% |
2% |
18% |
|
45 dB |
1% |
0% |
12% |
The EEA report states that while 55 dB Lden is a “fair” threshold for rail noise, use of 55 dB Lden for other noise sources leads to an underestimate of the actual burden. Table 1 gives the percentage highly annoyed at 55 dB Lden for rail noise as 4%, while the percentage highly annoyed at 45 dB Lden for aircraft noise is given as 12%. This means that to achieve annoyance levels approaching that regarded as “fair” for rail noise, the threshold for aircraft noise may have to be lower than 45 dB Lden. In fact, Section 2 of the EEA report gives 42 dB Lden as a general noise threshold above which annoyance effects start to occur or rise above background. It would therefore appear that the EEA report implies that the threshold for noise mapping where aircraft noise is considered to be a problem should be significantly lower than 55 dB Lden as currently used.
Conclusions
The EEA report recognises that levels of annoyance with aircraft noise are much higher for post-1990 studies than for pre-1990 studies. This paper compares the results for different annoyance models over the range of noise levels in the ANASE study (40.9 to 64.2 dB LAeq,16h). This analysis shows that annoyance levels predicted by the UK’s CAP725 relationship are generally lower than given by the EEA pre-1990 relationship, and much lower than given by the EEA post-1990 relationship. In contrast, the analysis shows that the much higher annoyance levels in the EEA post-1990 studies seem to be replicated by the ANASE study. Despite this, the Government continues to rely on the ANIS, Schultz and CAP725 aircraft noise relationships derived from social surveys carried out more than 25 years ago.
Until the issues of the ANASE study are addressed, it is suggested that Government policy should be based on guidance in the EEA report, including the specified relationship between annoyance and aircraft noise level. Although the EEA report gives increased levels of aircraft noise annoyance, it does not address all the objectives of the ANASE study. These objectives include the suitability of LAeq,16h as an indicator of community annoyance, the importance of numbers of aircraft flights, the relative importance of different times of day, and determining willingness to pay to reduce annoyance from aircraft noise. Further work is necessary to address these objectives.
It is concluded that there is an urgent need for updated guidance from the Government on the annoyance relationship for aircraft noise, and the threshold level at which aircraft noise is considered to be a problem.
References
[1] Good practice guide on noise exposure and potential health effects. EEA Technical Report No. 11/2010. European Environment Agency, 2010.
[2] Directive 2002/49/EC. Directive of the European Parliament relating to the assessment and management of environmental noise, 2002. Official Journal of the European Communities, L 189, 12–25.
[3] Position paper on dose response relationships between transportation noise and annoyance. European Commission Working Group, 2002.
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[5] CAP725, CAA Guidance on the application of the airspace change process. Civil Aviation Authority, 2007.
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[7] London Heathrow Airport Strategic Noise Maps 2006. ERCD Report 0706. Civil Aviation Authority, 2007.
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[9] ANASE: Attitudes to Noise from Aviation Sources in England. Final Report prepared for Department for Transport by MVA Consultancy, October 2007.
[10] Attitudes to Noise from Aviation Sources in England. Non SP Peer Review. Civil Aviation Authority and Bureau Veritas, draft July 2007, final October 2007.
1 LAeq,T = SEL + 10LogN – 10LogT, where SEL is event noise level (dB) for N events in T seconds
2 10Log(2/1) = +3 and 10Log(1/2) = -3