View all publications

5 Ambient standards

The regulations state that after 1 September 2005 regional councils and unitary authorities must:

  • monitor air quality in accordance with the methods specified in the regulations if it is likely that the ambient standards will be exceeded in an airshed

  • give public notice if the air quality in an airshed breaches the ambient standards.

5.1 Monitoring

Councils identified a total of 39 airsheds likely to exceed the ambient standards, as shown in table 5. The review shows that all councils are monitoring in accordance with the regulations in most areas that are likely to exceed the ambient standards.7 Auckland Regional Council and Environment Canterbury have the most extensive monitoring networks in the country, with a significant historical record (going back to the 1960s).

A number of councils are further undertaking co-located monitoring (ie, monitoring PM10 using different monitoring methods in the same location). This includes Auckland Regional Council, Environment Canterbury, Environment Waikato, Environment Southland, Otago Regional Council and Northland Regional Council.

The review reveals that five airsheds are likely to exceed the ambient standards in which councils are not monitoring in accordance with the regulations. It is noted that ambient air quality monitoring incurs significant expenditure, and that these airsheds all have populations less than 6000.8

Table 5: Monitoring of airsheds likely to exceed the ambient standardsa

CouncilAirshed likely to exceed – monitoredAirshed likely to exceed – not monitored
AucklandAuckland, Kumeu, Pukekohe 
Bay of PlentyRotorua 
CanterburyAshburton, Christchurch, Geraldine, Kaiapoi, Rangiora, Timaru, WaimateHanmer, Kaikoura, Temuka
Hawke’s BayAwatoto, Hastings, Napier,Whirinaki 
NelsonNelson A, Nelson B 
NorthlandMarsden Point, Whangarei 

Airsheds 1, 2 and 3 with monitoring carried out in:

Alexandra, Arrowtown, Clyde, Cromwell, Dunedin, Milton, Mosgiel, Ranfurly and Oamaru

SouthlandGore, InvercargillWinton
WaikatoHamilton, Putaruru, Taupo, Te Kuiti, Tokoroa 
WellingtonWairarapa, Wainuiomata 
West CoastReefton 

a In accordance with Schedule 2 of the regulations.

b Otago airsheds were gazetted collectively as Airsheds 1, 2 and 3. Monitoring need only be carried out in one area of these airsheds to satisfy the regulations. In reality, the following areas are also considered likely to exceed but are not being monitored continuously: Balclutha, Palmerston and South Dunedin.

5.2 Public notice

Since the ambient standards came into force on 1 September 2005, nearly all councils have measured breaches of the ambient standards. Councils that monitor and that have had no breaches are Horizons Regional Council, Gisborne District Council, Northland Regional Council and Taranaki Regional Council.

The regulations require councils to notify all breaches of the ambient standards through a public notice, and generally this has occurred. Three exceptions are:

  • Environment Bay of Plenty, which did not publicly notify exceedances of the sulphur dioxide ambient standard measured at Mt Maunganui during the summer of 2005–2006

  • Hawke’s Bay Regional Council, which did not notify six exceedances of the PM10 ambient standard measured by Ravensdown Fertiliser Cooperative at Awatoto during 2006

  • Marlborough District Council, which did not notify one exceedance of the PM10 ambient standard measured in Blenheim during 2007.

Summary information on these exceptions is provided in appendix 2. Appendix 3 provides example public notices from all councils.

5.3 Review of implementation

Ambient air quality monitoring and reporting are stand-out areas for implementation. The regulations’ explicit requirement for councils to monitor and publicly report has resulted in a dramatic improvement in publicly available information on ambient air quality. What is outstanding is that councils report ambient air quality monitoring of PM10 live to the internet in 34 areas:

  • Environment Bay of Plenty: Tauranga, Rotorua, Whakatane

  • Environment Canterbury: Rangiora, Kaiapoi, Christchurch, Ashburton, Timaru, Waimate, Geraldine

  • Environment Southland: Invercargill, Gore

  • Environment Waikato: Te Kuiti, Tokoroa, Taupo, Hamilton, Putaruru

  • Greater Wellington: central Wellington, Lower Hutt, Upper Hutt, Wainuiomata, Tawa, Karori, Masterton

  • Otago Regional Council: Alexandra, Clyde, Cromwell, Arrowtown, Ranfurly, Central Dunedin, Mosgiel, Milton

  • West Coast Regional Council: Reefton.

Environment Canterbury and Otago Regional Council also provide weekly updates via email to interested stakeholders, and Environment Southland reports PM10 monitoring results on regional television and radio daily.

Actions to reduce emissions require justification to the public and council, and credible air quality data makes this possible. However, such extensive monitoring has not come without a cost: ambient air quality monitoring is expensive, and all councils identified this as a key barrier to implementation of the regulations.

What can the Ministry do?

Although all councils carry out some form of quality assurance and data validation of their ambient air quality monitoring data, few hold accreditation and the approaches vary. Only five councils carry out external audits of their ambient monitoring programmes regularly.9 Several councils asked the Ministry to specify minimum monitoring and reporting requirements. There was further strong support for the Ministry to take more of a leadership role in monitoring through the provision of annual audits and workshops to address issues such as differences between monitoring methods.

Effectiveness of monitoring and public notices

Councils were largely non-committal on the question of the effectiveness of the monitoring and public notice requirements of the regulations. A number commented on the limited readership of public notices and reported very little interest in exceedances reported. An exception was Environment Southland, which has fielded enquiries following the presentation of monitoring data supplied to regional television. The Ministry notes the limited readership of public notices, but overall views the monitoring and public notification requirements of the regulations as being highly effective.


7  Except Taranaki Regional Council, which considers no areas likely to exceed in their region.

8  Initial capital outlay and set-up costs for a PM10 monitor are around $50,000–$70,000.

9  Auckland Regional Council, Environment Bay of Plenty, Environment Canterbury, Gisborne District Council, Otago Regional Council and Tasman District Council.

[ |