Westport subject to winter air monitoring

Nicole Mathewson Reporter from The Press

By Brendon McMahon, local democracy reporter

Westport air quality is being surveyed again this winter.

It follows a winter survey by the West Coast Regional Council in 2022 that found air quality in parts of the town might exceed monitoring standards.

An environmental science report to council's Resource Management Committee on Tuesday [June 13] says the range and number of monitoring sites has been expanded to 18 locations for the new winter survey.

"The instruments will be monitoring fine particles of particulate matter in the air (PM 2.5), which can be harmful to human health," the report says.

PM 2.5 is often associated with solid fuel burning.

"On the West Coast we generally see higher levels of particulate matter in the air over winter months due to solid fuel burning for domestic home heating."

Coal fires have traditionally been the main source of domestic heating in Westport and other West Coast towns such as Reefton and Greymouth.
However the latest monitoring project was not targeting individual emission sources but designed to show the levels and variation of PM across the town during the winter months, the report says.

This would help council identify "if there are any air quality issues" in Westport that would require further investigation.

The same survey in 2022 indicated that air quality in parts of the town may exceed monitoring standards, but it was decided to run a repeat in 2023 due to the variability of environmental and anthropogenic factors such as wind speed, air temperature and burning habits.

"Having two winters' worth of data will be more robust and provide a better, more informed understanding of Westport's air quality."

The last PM monitoring in Westport was nearly 20 years ago.

Last winter, the appearance of monitoring stations around Westport prompted some concerns about the council's motive.

Former councillor Laura Coll-McLaughlin, of Westport, noted at the council table in July that social media comment about the air quality project reflected some "mixed community sentiment".

There was also suspicion of "some ulterior motives" but it was positive the council was gaining baseline data, she said.

Environmental science staff pointed out that council was statutorily required to monitor air quality and would need to do a bigger body of work in future around that while allowing for a transition in the type of heating local people could use to keep their homes warm and dry.

The other West Coast town subject to ongoing air quality monitoring by council for years is Reefton.

It sits in an inland basin with typically still weather during winter, resulting in 'smog'.