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Badgerys Creek Airport – Comments on Draft EIS

by Ben on December 17th, 2015

Ben Scott  (BSc. M.AppSci)



A key component of the Draft Environmental Impact Statement (EIS) for the proposed airport at Badgerys Creek, NSW is the impact of aircraft noise during operation of the airport.  This document uses an independent spatial analysis of flight paths, altitudes and noise levels to highlight inaccuracies in the noise assessment and areas where information should have been provided to the public but has been omitted from the EIS.  Whether deliberate or as a result of poor quality control, the identified deficiencies result in the EIS portraying the proposed airport as being less harmful than it is likely to be in reality.  The EIS therefore does not serve its intended purpose of providing a rigorous and independent assessment of the environmental impacts of the development.

It should be noted that while these particular comments focus on the aircraft noise assessment, similarly significant deficiencies in other parts of the EIS have been highlighted by other reviewers, particularly in relation to rounding of emissions figures, which have been found to vary between different parts of the document by a factor of 1000.

Noise Levels

The noise assessment presented in the EIS is unsuitable for the proposed airport location as it has been assessed only on the basis of noise levels and flight frequencies that would be acceptable in a city environment.  The design, analysis and presentation of the noise assessment are based on a misleading assumption that aircraft noise below these standards is of no consequence.   Examples of this approach are as follows:

  • The use of noise standards (ANEF, ANEC, N70 and N60) alone for assessing impact on residential areas (Appendix E1, page 15-18). These measures are more suited to industrial and high density urban environments.  The EIS does not adequately explore measures of noise disturbance relevant to quieter environments.
  • The EIS provides single event contours for arrival and departure to the airport (e.g. Appendix E1, page 37-46), however the contours are only symbolised down to 60 dBA, which is designed to mislead the reader into thinking that noise below 60 dBA is of no concern.
  • The assessment of noise in recreational areas (Appendix E1, page 82), including camping, walking and picnic sites in natural environments, is also assessed using thresholds of 60 and 70 dBA and do not consider the location of lower noise level impacts.
  • The assessment of noise impacts on the Greater Blue Mountains World Heritage Area only considers noise levels of 50 dBA and above (e.g. Volume 2. Page 539-540).


The EIS must address the impact of aircraft noise at levels suitable for the urban and natural environments that occur under the flight path. The impact of noise on a community and/or natural environment must be assessed by comparison with the normal background noise level.  An indication of these levels is available in  noise monitoring results presented in Table 2-1, Appendix E2, Page 10.

New Picture

The proposed flight paths overlay significant portions of the Blue Mountains National park and World Heritage Area.  The towns of the Blue Mountains have a vital tourism industry which is centred around its quiet, peaceful and natural environment.  In vast areas of the Blue Mountains which are under the proposed flight path, background noise levels would frequently be as low as 30 db in urban or semi-urban environments and 25 db in bushland environments.  A noise level of 50 dBA is roughly equivalent to the sound of a truck passing on a highway 50m away.  The EIS works on the assumption that noise at this level would be acceptable on a regular basis over wide swathes of the over Blue Mountains, even in its quietest, most remote areas.  This is completely unacceptable.

Figures 1, 2, 3 and 4 provide single event noise contours for 747 and A320 aircraft which show the area across Blue Mountains towns and World Heritage Area that would be subjected to noise levels between 30 and 60 decibels.  The modelling has been compared, and for the most part appears to conform with, the modelling in the EIS, however the maps are symbolised down to 30 dBA.

Click here for Figures 1-4 in the form of dynamic web maps


Brief methodology steps for analysis:
* digitise flight plans from maps
* convert to distance from takeoff
* use regressions of distance vs altitude to estimate altitude for each 50 m grid cell along the flight path and where necessary adjust using altitudes in published flight path plans
* create layer of distance from flight path and altitude of closest flight path for whole study area
* use basic trigonometry to calculate direct distance to flight path, incorporating the elevation of each ‘observation point’ relative to the flight path
* use regressions of altitude vs decibels to estimate sound levels at every point in the study area (using information from figure 7 below, sourced from the draft EIS Volume 2, page 22)


Figure 1 – Estimated single event noise contour for 747 arrival symbolised to 30 dBA.

New Picture (1)

Figure 2 – Estimated single event noise contour for 747 departure symbolised to 30 dBA.

New Picture (2)


Figure 3 – Estimated single event noise contour for A320 arrival symbolised to 30 dBA.

New Picture (3)

Figure 4 – Estimated single event noise contour for A320 departure symbolised to 30 dBA.

New Picture (4)

The noise affected area increases even further under the draft flight plan for a future double runway scenario in 2063 (see figure 1), which would for all practical purposes see the whole of the Blue Mountains World Heritage area and Blue Mountains towns subjected to aircraft noise, and would see total daily aircraft movements (see table 2-3, Appendix E1, page 23) similar to the current traffic in the busiest airports in Europe, including Heathrow.

New Picture (5)

Figure 5 – Potential Flight Paths by 2063 (Figure B-1 in the EIS appendix E1)

New Picture (6)

The EIS must properly assess the impact of noise levels using assumptions of acceptable noise which are suitable for Wilderness, National Park and quiet bushland residential areas.  It must contain an adequate assessment of options to prevent aircraft noise being heard in the World Heritage Area, and to keep noise in bushland residential areas to levels close to background levels. 

Departure Climb Rates and Altitudes

One of  the key references for the public about the impact of flights from the airport is the flight plan maps (figures ES 8 and ES 9, Volume 1 page 20-21, figures 5 and 6 below).  These show point altitudes at various points along the potential flight paths.

Figure 5 – Flight plan map, 05 track

New Picture (7)

Figure 6 – Flight plan map, 23 track

New Picture (8)

The departure point distances in the maps, and the noise assessment, assume that 747 aircraft would climb at the same rate as A320 aircraft.  Elsewhere in the EIS (figure 10-2, Volume 2, page 22 – figure 7 below), however, there are diagrams indicating the altitude during departure and arrival for both 747 and A320 aircraft, which show 747 aircraft climbing at a much slower rate.  There is no indication in the EIS of the method by which climb rates for noise modelling were determined,  whether the single assumed climb rate is possible for 747 aircraft, and if it is possible, whether it results in increased noise which should be taken into consideration in the assessment.

Figure 7 – Climb and descent rates and associated noise levels for 747 and A320 aircraft, sourced from the EIS Volume 2, page 22.

New Picture (9)

The EIS must include this information and must separately model the correct climb rate for each aircraft if this is necessary as a result of aircraft specifications.  If the climb rate in the diagram above is assumed for 747 aircraft the single even noise contours are significantly different to those published, evidenced by a comparison of figure 8 with figure 3 on page 4 above.

Figure 8.  Single event noise contours based on climb rates in Figure 10.2 of the EIS Vol 2, page 22.

New Picture (10)


The Blue Mountains contains some of the largest contiguous areas of native forest in Australia, preserved as wilderness and World Heritage Listed because of their beauty and their lack of disturbance by European people.  These areas are bordered by a series of towns which have been favoured by tourists and residents as a place of quiet retreat and recreation for over 150 years.

The Badgerys Creek airport Draft EIS is completely inadequate for assessment of the impacts of aircraft noise on these areas. It is designed as if the region is just another patch of inner city urban sprawl, and in doing so paves the way for its substantial and  permanent degradation.  Instead, the final EIS must comprehensively assess the impact of proposed flight paths using methods suitable for the region, and propose suitable alternatives which will see the quiet beauty of the Blue Mountains preserved for future generations.


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