Background
On 1 December 2022 Airways implemented a new flight path system (DMAPS) which was approved by Wellington International Airport Limited (WIAL). This was done without consultation with the northern suburb residents of Johnsonville, Broadmeadows and Khandallah, despite it being noted that "the change in flight departure paths may be noticed by some residents in the Johnsonville/Khandallah area". - Read more.
Whilst WIAL has stated, "In cases like this public consultation isn’t normally undertaken". A more inclusive approach was adopted in 2018, arguably establishing a precedent for the conduct of flight path changes that would allow residents comparable justice. In 2018, public consultation was conducted, as was a 12-month trial period, and residents of the northern suburbs were notified by post when a change in flight path occurred with similar justifications. In 2018 the change process specifically welcomed and incorporated community feedback. - More here.
An initial acoustic report commissioned by WIAL states that noise levels are 'reasonable' and that there has been 'generally an imperceptible increase in noise', however, this is disputed by residents. As is the suggestion that this is a return to usual, pre-covid noise. The February 2023 acoustic assessment evaluated data from one noise monitor placed at a much lower altitude than the highest affected suburb - Broadmeadows, which is located 300m above sea level. The single noise monitor is also depicted to be close to the original flight path, not where the difference in noise would be greatest, at the furthest point from the previous flight path (Broadmeadows). The WIAL website and the noise contour within this report, do not include the suburbs of Ōhāriu Valley, Ngaio and Crofton Downs, where residents are also complaining of increased noise. The report analyses a 'single noise event' of a domestic flight to Auckland on an A320 which could be seen as a best-case scenario. WIAL has accepted that an international Boeing 737-800 flight increases the noise levels by an additional 3 decibels (later reported as 5dB). Still, a single noise event of this flight wasn't reported. Boeing 737-800 jets fly over the suburbs daily, with the first departing in the early hours of the morning. By comparison, the 2018 PBN trial included readings from 4 noise monitors placed along the proposed flight path, before and during the trial to gather benchmark data, to accurately determine the effects on residents along the new flight path. The first Marshall Day report is dated 14 February 2023, post-implementation of DMAPS.
Since the DMAPS change was implemented, residents of these suburbs have been experiencing a distressing increase in noise levels, which is becoming more acute and not less impactful as time progresses. WIAL has claimed that "a change in noise patterns is more disruptive than the noise level itself ", however two years on, the increased noise level is continuing to impact residents' sleep, peace and enjoyment of their homes - inside and outside, exacerbating health conditions and disturbing working-from-home setups. Read our neighbours' impact stories. WIAL's 'Game Changer' announcement in November 2024 threatens to worsen the situation, with runway modifications enabling longer-haul flights and larger aircraft that are reportedly 50-100%, louder than the current Boeing 737-800 and Airbus A320.
Following pressure from Plane Sense and the community, WIAL and Airways agreed in April 2023 to install 4 out of the 6 requested sound monitors in the affected suburbs. Installation finally took place between 12 July and 25 September and noise data was captured until 26 November 2023 (full sound monitor timeline can be found in our 19 July 2023 post). Plane Sense has been denied access to the raw data for independent analysis and WIAL maintains that the Ministry of Health's Public Health specialists must submit a written request to justify their need to access and interpret this data, to analyse the effect of noise on the health and well-being of residents. Plane Sense continues to push back against the use of subjective terms such as 'reasonable' and 'acceptable' in Marshall Day reports, particularly as the impact of noise on health and wellbeing is not within Marshall Day's field of expertise. The subsequent sound report, whilst still not sufficiently analysing the extent of single noise events vs ambient conditions (where data hasn't been averaged out over periods when planes are not flying - ie. in southerly conditions and overnight), generally supports the residents' concerns. Plane Sense findings from the report can be found in the March 2024 post here. Marshall Day's conclusions about reasonable noise differ from their founder's evidence in a July 2024 Auckland case. In that case, noise levels during a flyover were expected to be around 75–80dBA and drop to ambient levels after 30–60 seconds (the same levels of noise measured by Marshall Day in 2023 and experienced by the Plane Sense community). Mr Day gave evidence that the projected noise level constitutes a significant adverse effect on a residential development, that based on community response studies undertaken by the World Health Organisation and Federal Aviation Administration - 38 to 52 per cent of people would be expected to be highly annoyed living in this noise environment, and residents in the outdoor areas of the Development or indoors with windows open would need to shout or pause a conversation for 30 seconds every time an aircraft passed overhead.
Since Plane Sense investigations began, the team has built a timeline from Airways documents obtained by resident Official Information Act requests. Emails (including some omitted from Airways OIA response to Plane Sense) disclose that WIAL approved DMAPS on 9 August 2022 just 24 hours after receiving an 'initial outcomes' email with 'more to come' from Marshall Day, on 8 August 2022. This just met Airways' approval deadline of 10 August 2022, a delay or public consultation would have impacted a 1 December 2022 implementation date. (See our 1 September 2023 post here). WIAL and Airways have declined to comment on the timeline of events Plane Sense has deduced from OIA material. Through OIA requests and conversations with the CAA, we believe that DMAPS wasn't officially approved through the correct process, therefore making DMAPS invalid. After pointing out non-compliance with the Civil Aviation Rules, the CAA gazetted the flight tracks in December 2023. In our opinion, this attempt to validate the procedures more than a year after they were published to flight crew does not have retrospective effect and the purported validation may not be effective anyway. Discussions with the CAA about the Director's statutory duty to “Monitor adherence, within the civil aviation system, to any regulatory requirements relating to … public health” have resulted in the CAA claiming that the obligation is minimal.
Despite domestic readings of up to 80 decibels, residents of the northern suburbs are not entitled to the WIAL Quieter Homes package. The Quieter Homes package aims to reduce aircraft noise within residential homes to 45 decibels. WIAL has said that homes within the DMAPS flight path can expect internal noise between 45-50 decibels based on the noise assessment. Residents are taking readings of more than 45-50 decibels within their homes and the increase between everyday noise and a flight overhead can jump 20-30+ decibels, which is greatly felt. The February 2023 acoustic assessment advises of a 1-2 decibel increase in noise generally, whereas the December 2023 assessment reports a 4-5 decibel increase. Decibel levels are like the Richter scale, an increase in decibels results in noise level intensity increasing exponentially. The Wellington Council District Plan (page 29) recognises that Airport noise "is a significant environmental effect and is experienced well beyond the boundaries of the Airport", and that "it can have a substantial effect on residential quality of life".
Plane Sense has consistently challenged the averaged decibel levels in reporting and pushed for peak noise levels vs ambient noise levels. Residents are not experiencing averages, they are experiencing noise events of aircraft that dramatically escalate sound levels from typical, quieter background noise. With the installation of additional sound monitors, negotiated by Plane Sense, it is possible to see that single noise events of aircraft do not vary greatly from the decibel readings experienced around the airport. This is despite the northern suburbs' ambient noise appearing lower than city noise in general, therefore creating a greater difference in noise level fluctuation. Unfortunately, pre-DMAPS benchmark data from these sound monitor locations in the suburbs does not exist, as it was not collected for comparison.
Residents worry about increased disturbance as the noisier international flights rise to their pre-covid numbers and beyond. WIAL has said (February 2023) that international flights are at 64% of 2019 international departures and residents can expect these to reach 100% in 3-4 years. WIAL has also announced runway modifications to increase international capacity. The flight path above these suburbs is the path used by domestic and international jets, whereas prop-planes and lighter aircraft take alternative paths. WIAL has stated "There is no limit on number of flights", when pressed by residents about the future disruption they can expect. Residents have already experienced flights departing within 1-2 minutes of each other. Since Plane Sense was formed, WIAL has also announced additional Qantas flights to Brisbane and Melbourne and an increase of the louder Boeing 737-800 flights.
It has also been broached with WIAL that the neighbourhood is noticing less native birdlife in the suburbs, such as the recovering populations of tūī, kākā and kererū. The affected suburbs incorporate the naturally beautiful Khandallah Reserve, which is part of a corridor of native bush that runs from Zealandia to Otari Wilton Bush, and onto Johnsonville, providing a home for native birds and supporting their numbers as their populations recover. The Reserve surrounds Mount Kaukau/Tarikākā - meaning 'where the parrots nest'. Over the years, residents have enjoyed and encouraged native birdlife into the area and their gardens, as a result of the extensive conservation work by Zealandia and with active participation in the Predator Free initiative. The Wellington City Council website reports "Between 2011 and 2021, average annual counts of kākā have increased by 270%, kererū by 243% and tūī by 74%", and "These results are largely due to the predator-free Zealandia sanctuary, and the measurable 'halo' effect on native forest bird communities". WCC, which owns 34% of WIAL, states "Our mission has always been to connect people with nature, and for them to feel an emotional attachment and want to protect it". Forest and Bird responded to residents' concerns confirming that "Overseas data definitely implies that airport noise does affect birds". When asked which environmental agencies were engaged with when increasing flights over and near the Reserve, WIAL did not name any environmental agencies and stated, "We are not aware of any evidence this has had any impact on birdlife". Sustainability is one of WIAL and Airways' justifications for the flight path change.
Representatives have been analysing Official Information Act request information, to discover what process was followed, the legality of residents not being consulted, whether aircraft are flying in closer proximity to land and houses on the new flight path vs the original flight path (due to the higher altitude of the suburbs). Also questioning and putting into perspective the sustainability claims of the new system, given there are more than 18,000 flights in out of Wellington per quarter (January-March 2023). View Plane Sense's Community Meeting presentation, with findings to date (June 2023). Airways' sustainability claim refers to car emissions and not plane emissions and is less impressive when converted to plane emissions, particularly in light of increasing aircraft departures.
The northern suburbs do not have in-person representation at the Air Noise Management Committee, which is represented by as few as 4 Wellington residents, from the Eastern and Western Wards. Plane Sense representatives have engaged with both Airways and WIAL, also with the Mayor who sits on the Board of Directors at WIAL. Suburbs impacted by aircraft noise as a result of DMAPS do not feature in WIAL's Airport Noise Management Plan, or in WIAL's Air Noise Committee meeting minutes until March 2023 - post-implementation.
Plane Sense has attempted to work collaboratively with Airways and Wellington Airport since March 2023. It has worked tirelessly as a voluntary organisation to have the original departure path reinstated over the harbour, by agreement with all parties. However, Wellington Airport and Airways have offered no commitment to change, despite the December 2023 acoustic report validating resident concerns and establishing that the original noise modelling work was inadequate and inaccurate. Plane Sense has filed and served the parties involved to account for public health, safety and legal issues associated with the DMAPS flight path change. Plane Sense is fundraising with a goal of $25k, donations can be made here. Have questions? - see our FAQs here.
Plane Sense is calling for Airways and Wellington Airport to reinstate the over-water departure procedure for Runway 34, and as a matter of urgency - to minimise the continued suffering of our community.
