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State of the Environment Environment New Zealand 2007 - Summary Online version Section three: State of the environment
Section three: State of the environment
Air
New Zealand has good air quality in most places for most of the time. Nevertheless, emissions from wintertime home heating and road traffic can affect air quality in about 30 locations around New Zealand. Around 53 per cent of New Zealanders live in these locations. Both large urban areas and small settlements can be affected by poor air quality.
In most areas that experience poor air quality, the cause is high winter levels of small particles from coal and wood home heating. These are known as PM10 particulates, because they are smaller than 10 microns in diameter (about a fifth of the thickness of a human hair). The Auckland area, home to about one-third of the country’s population, also occasionally experiences high PM10 particulate levels from road transport. Regional PM10 particulate monitoring networks have been expanded and upgraded to ensure continuous monitoring where levels are of concern.
Air quality and human health
Pollutants in the air can affect human health because they are inhaled into our lungs. Vulnerable groups such as the very young, very old, and those with underlying respiratory or cardiac disease, are particularly at risk. In New Zealand, around 1,100 people die prematurely each year from exposure to air pollution. Of those, the number of people dying prematurely from traffic-related air pollution is close to the number killed in road accidents.
PM10 particulate levels
Figure 3.1 on page 32 shows that PM10 particulate levels appear to be falling in some of the main centres of population, although the influence of weather on air pollution makes it difficult to assess trends. Levels of PM10 particulates at roadside locations in Auckland appear to have fallen over the past 10 years.
Overseas, health experts have, in recent years, become concerned about the health impacts of even smaller particles in the air (PM2.5). The monitoring for PM2.5 particulates that has been carried out in New Zealand so far shows a strong correlation between high levels of PM10 particulates and high levels of PM2.5 particulates.
Air pollution in a rural community during winter.
Source: Courtesy of Greater Wellington Regional Council.
Local action on air pollution
Auckland Regional Council 0800 Smokey campaign
In August 2000, Auckland Regional Council began a public education campaign designed to raise awareness of Auckland’s air pollution problems from motor vehicles. The aims of the 0800 Smokey campaign were to:
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raise awareness that motor vehicle emissions cause more than 80 per cent of the air pollution in Auckland and that owners should tune their vehicles to reduce the impact of motor vehicle emissions
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promote the 0800 SMOKEY hotline and website through which people could report smoky vehicles
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raise the profile of air quality in the region to influence national policies on fuel quality and vehicle importation.
Throughout the campaign, free exhaust emission checks were offered to vehicle owners.
Over a 15-week period, 20,000 people reported 23,000 different smoky vehicles. One vehicle was reported 67 times.
Nelson City Council and Tasman District Council Good Wood scheme
Firewood retailers are encouraged to become ‘Good Wood’ suppliers who agree to supply dry wood (or wood that will be dry for the following winter). Suppliers must have moisture meters to confirm the moisture content of the wood supplied. Retailers who agree to the code can use the Good Wood logo. Regular marketing and promotion of Good Wood suppliers is carried out by the Nelson City Council and Tasman District Council.
Nelson City Council Smoke Patrol
Nelson City Council has a dedicated smoke patrol officer. The officer’s role is to identify excessively smoky domestic fires and offer the householder advice on ways to reduce smoke, information about Good Wood, and financial assistance to upgrade old burners and improve insulation.
National environmental standards for air quality
National air quality standards adopted in 2004 are helping improve air quality, including by reducing PM10 particulate levels (see box ‘National environmental standards for air quality’).
National environmental standards for air quality
The Resource Management (National Environmental Standards Relating to Certain Air Pollutants, Dioxins, and Other Toxics) Regulations 2004 set air quality standards for PM10 particulates, nitrogen dioxide, carbon monoxide, sulphur dioxide, and ground-level ozone. In addition, certain activities are prohibited, such as burning tyres, bitumen, coated wire, and oil in the open. The standards also prohibit the use of incinerators at schools and health care institutions, unless authorised by resource consent. New high-temperature waste incinerators are also prohibited.
The national environmental standard (NES) for the five air pollutants mentioned above is defined in terms of a maximum concentration of the pollutant in the air and the frequency with which that maximum concentration may be exceeded without breaching the NES.
The NES requires air quality to be measured and publicly reported by regional councils and unitary authorities wherever air pollution exceeds levels set by the standards. Councils have identified airsheds where PM10 particulates are known, or suspected to be, of concern. PM10 particulate levels in these airsheds are required to comply with the ambient air quality standard by 2013. After August 2013, no resource consents to discharge PM10 particulates to air can be granted if the air quality standard is still being breached (that is, exceeded more than once in 12 months).
The NES also includes a design standard for new wood burners installed after September 2005 to reduce particulate emissions and provide better heat efficiency. Although the wood burner standard only limits emissions of small particulates, it has the additional benefit of controlling emissions of other harmful pollutants such as carbon monoxide, volatile organic compounds, hydrocarbons, and dioxins.
See figure at its full size (including text description). The box ‘Other air pollutants monitored in New Zealand towns and cities’ shows the status of other air pollutants in New Zealand, including nitrogen dioxide, carbon monoxide, sulphur dioxide, ground-level ozone, benzene, and lead.
Other air pollutants monitored in New Zealand towns and cities
Environment New Zealand 2007 presents an extensive overview of air quality monitoring of contaminants other than PM10 particulates. In brief:
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Levels of nitrogen dioxide are at an acceptable level around New Zealand, with the exception of some locations in Auckland that are affected by traffic emissions. Emissions of nitrogen dioxide in Auckland appear to be increasing.
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Levels of carbon monoxide, mostly from traffic emissions, were of concern 10 years ago. Since then, levels appear to have fallen at sites that have historically experienced high concentrations. The improvement is most likely due to improvements in vehicle technology.
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Sulphur dioxide concentrations declined in the 1980s and are considered to be low in most parts of the country. The exceptions to this are areas around the Marsden Point Oil Refinery and some other individual sources.
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As a result of traffic emissions, areas around Auckland, Hamilton, and Christchurch were identified in the mid-1990s as having the greatest potential for elevated levels of ground-level ozone. However, monitoring indicates that ozone levels are satisfactory in these locations.
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Benzene levels at monitored locations are satisfactory. Roadside levels are higher than in residential areas, but appear to be improving. This is probably due to changes in fuel composition.
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Lead was eliminated from New Zealand petrol in 1996 and airborne lead levels are now very low.
Government action on air quality
Warm Homes initiatives
Through the Warm Homes project, central government is working with local government to help New Zealanders reduce the pollution effects of home heating while staying warm. The project aims to ensure all New Zealanders heat their homes cleanly, efficiently, and sufficiently. Pilot programmes were run in Tokoroa, Timaru, and Taumarunui to retrofit homes with insulation and new heating sources, and evaluate the impacts of this on air quality and health. In 2006, the Warm Homes project also ran seven community workshops in six regions across New Zealand.
Transport initiatives
Petroleum Products Specifications Regulations 2003
These Regulations specify the technical requirements for petrol and diesel supplied for retail sale (excluding aviation, jet boat, and motor racing). Progressive improvements in fuel specifications have reduced the amount of pollutants such as PM10 and benzene that are emitted from vehicle exhausts.
The Vehicle Exhaust Emissions Rule
This Land Transport Rule, introduced in 2003, requires all motor vehicles entering the New Zealand fleet for the first time to have been manufactured to the applicable emissions standards specified in the rule. Since 2006, the rule has required all vehicles to undergo a visible smoke test check at every compliance test (that is, border entry, warrant of fitness, and certificate of fitness inspections). This complements the Land Transport (Road User) Rule 2004 which requires that vehicles do not emit visible smoke for more than 10 seconds.
At the time of writing, government is consulting on proposed tighter emissions standards for new vehicles and used vehicles entering New Zealand.
Reducing the sulphur content of diesel in New Zealand
In 2002, the Government introduced regulations that reduced the sulphur content of diesel. By September 2002, the sulphur content of diesel available in Auckland and Northland had reduced from 3,000 parts per million to 1,000 parts per million.
In August 2004, levels were further reduced throughout New Zealand to 500 parts per million. This was followed by another decrease to 50 parts per million in January 2006, representing a 60-fold reduction in sulphur content since 2002. The sulphur content in diesel will be further reduced to 10 parts per million in January 2009.
Clearing the air
Today, the main focus for improving air quality in New Zealand is to reduce emissions of PM10 particulates from home heating and transport. Now that regular monitoring of air quality in managed airsheds has been put in place through the national environmental standards, the focus has shifted to monitoring how levels of PM10 particulates are tracking against the national environmental standard target set for 2013.
As the Resource Management Act 1991 is unlikely to be effective in controlling air pollution from traffic, other work is underway to minimise the impact of air pollution from road transport. This includes a visible smoke test when vehicles go for a warrant of fitness, and emissions standards for imported vehicles.
But, as noted in the Transport section, improvements in fuels and vehicle technology alone will not be enough to reduce air pollution from road transport. Further measures, such as a well-functioning and convenient public transport system, and, in the long run, changing the shape of our urban environment to reduce our dependence on motorised transport, will also need to be part of the mix.
Future work on improving air quality in New Zealand is also likely to focus on developing a better understanding of PM2.5 particulate concentrations around New Zealand.
Busy Auckland motorway.
Source: Courtesy of Gavin Fisher.
