Media release

Dunedin achieves five consecutive years of air quality compliance

Thursday 24 November 2016

Central Dunedin has notched up its fifth consecutive year of compliance with air quality standards.

The achievement was praised today by the chairwoman of the Otago Regional Council’s technical committee, Cr Maggie Lawton, who noted the contribution made by large industrial emitters to this result.

A summary of 2016 air quality results presented to councillors yesterday noted that in Dunedin, PM10 (air particulate) levels have dropped significantly in the past five years, and have remained low throughout that time.

There were no breaches of the National Environmental Standard for Air Quality in Dunedin this year, a pattern that goes back to 2011.

Cr Lawton said improvements in industrial air discharges and the replacement of older, inefficient solid fuel-burners with cleaner burning systems were the most likely contributors to this perfect compliance record.

PM10 levels increased in Mosgiel from 2007 through 2011, but have since started to decline with this year having some of the best year-round air quality over the past 10 years.

Overall, the concentrations of pollutants being discharged to air from domestic and industrial chimneys in Otago have been gradually reducing during the past 10 years.

ORC conducted air quality monitoring this year in Alexandra, Arrowtown, Clyde, Cromwell, Balclutha, Dunedin, Milton, and Mosgiel to measure the amount of PM10 in the atmosphere.

The Alexandra, Arrowtown, Dunedin and Mosgiel monitoring is done year-round while in Balclutha, Milton, Clyde, and Cromwell this is limited to the colder winter months.

The National Environmental Standard for air quality was exceeded in Alexandra on 39 days this calendar year, followed by Milton (35), Cromwell (33), Arrowtown (30), Clyde (17), Balclutha (11), Mosgiel (8), and Dunedin (0).

In Alexandra, while year-round PM10 values do not indicate any significant trend over the past 10 years, on days where the national standard was exceeded a small but steady decrease in those highest values has emerged.

Cr Lawton said that the replacement of older, inefficient wood burners with newer, more efficient models was the most likely cause of this improvement.

In Arrowtown, PM10 values have been much more variable year-to-year but with a significant decrease from 2007 to 2011. In 2013, the monitoring equipment was moved to an alternate location in Arrowtown, where PM10 levels are generally higher, but improvement was still evident over the past three years.

“Improving air quality in Otago, particularly in Central Otago, is challenging – however, these slight but sustained improvements over a 10-year period are encouraging,” Cr Lawton said.

“I am confident that through the development of an air strategy and investigation of new, smart technologies, these improvements will continue so we can all enjoy fresh, clean air, and preserve the magnificent landscapes Otago is famous for."

For more information please contact

Cr Maggie Lawton
Technical committee
Ph 0275377711

Dr Gavin Palmer
Director engineering, hazards, and science
Ph 0800 474082 or 0274 933960

ORC Communications contact

Mark Peart
Team Leader Communications – Channels
Ph 0800 474082 or 027 5312620