Air quality review could see 20-fold rise in pollution breaches in Blenheim

Warm houses and polluted air, or cold houses and clean air?

That’s the balancing act troubling Marlborough District councillors during a discussion on ways the region could meet the Government's “unachievable” new air quality regulations.

Councils currently had to worry about particulate matter smaller than 10 micrometres under New Zealand’s air quality regulations, but the Government was proposing the focus instead shift to particles under 2.5 micrometres, which went deeper into the lungs.

Marlborough District Council air scientist Sarah Brand says if the proposal went ahead, Blenheim’s air pollution breaches could increase 20-fold, prompting “significant” management changes.

Marlborough's capital is already struggling to meeting the Government's current air quality target for bigger particles (PM10), having gone over the pollution limit almost every year since 2006.

The limit is more than 50mcgs of bigger air pollutants in a cubic metre of air and exceeding this upped the chance of health issues.

Air pollutants could come from human activities, like heating homes or running vehicles, or from natural sources, like dust, pollen and salt.

Marlborough District Council environmental scientist Sarah Brand says Blenheim will not be compliant if new air quality rules go ahead. Photo: Chloe Ranford/LDR.

The region's new environment plan says Blenheim would still have days with dangerous levels of pollution even if homeowners replaced their older, pollutant burners with modern, compliant ones.

She says if the new rules were adopted later this year, as proposed, the council would need to roll out “serious management measures”.

Councillor Jamie Arbuckle says he thought people inside the Blenheim airshed would need to take even more drastic steps, like stop burning wood, for the town to meet the proposed new rules.

The airshed covered most of Blenheim, from Waterlea Racecourse to Boulevard Park on Taylor, and from Springlands to Riverlands.

“How do we comply, because it seems impossible going forward.”

A 2017 report found most of Blenheim's air pollution comes from heating. Photo: Supplied.

Blenheim would have clocked 42 breaches last year had the Government’s proposed new limit of less than 25 micrograms of smaller (PM2.5) pollutants in cubic meter of air been in place.

Councillor David Croad says if Blenheim struggled to meet the current pollution limit, even with plan rules requiring new burners to be low-emission, then the new proposals were “just unachievable”.

Councillor Gerald Hope says he did not want the new rules to result in a ban on woodburners, “the most efficient and affordable heater”.

Gerald pointed out that cold homes led to health problems.

But Marlborough Mayor John Leggett says this was a “circular argument” because polluted air could also trigger health issues.

He asked councillors to discuss the issue at another time.

Blenheim's air was unsafe to breathe for two days in May last year. Photo: Chloe Ranford/LDR.

Sarah says the Government's new air quality proposals were based on World Health Organisation guidelines on PM2.5 which were “dated”, “not based on New Zealand conditions” and under review.

She says if the new rules were adopted later this year, as proposed, the council would need to roll out “serious management measures”.

Environment Canterbury had cracked down on air emissions by banning open fireplaces and phasing out low emission burners for ultra-low alternatives. Marlborough’s council could do the same.

“The goalpost [for air pollution] does need to change ... but how we get there is a whole other kettle of fish,” she said. “The community has done a significant amount of work in this space already [and] we’re asking them to do more. How can we go about doing that?”

Her report detailing last year’s breaches was shown to councillors at a council committee last week, and forwarded on to full council.