Marlborough region

Air Quality

Air quality in Marlborough is generally good but Blenheim has an air quality problem during winter, most of it due to home heating. All current monitored towns are shown.

Marlborough’s air story

Air quality in Marlborough is generally good. The main source of air pollution in Marlborough towns is smoke from home heating. Other sources of contaminants may include industry, traffic and rural burning, as well as natural sources (sea salt, dust and pollen). Blenheim has an air quality problem during winter with the main source at this time due to home heating. During the winter our cold, still, frosty days mean the smoke from home heating isn’t blown away and gets trapped until the air warms up or the wind picks up.

The particulates from smoke (and from sea salt, dust and cars) are known as PM₁₀ and these tiny particles can get deep in to our lungs and cause health issues for some people. During winter in Blenheim, daily average PM₁₀ concentrations can exceed national guidelines. The National Environmental Standards require no more than one day per year in Blenheim when PM₁₀ is greater than 50 µg/m³, from 1 September 2016.

You can find information for all current monitored towns below and see how they compare from year to year, and against the national guidelines. Marlborough District Council monitor air quality in Blenheim at one site in Redwoodtown, but has historically undertaken monitoring in other suburbs to understand air pollution across Blenheim. Trend data on PM₁₀ for Blenheim has shown no measurable decline or improvement in air quality.

We all have a role to play in achieving cleaner, healthier air to breathe. Marlborough District Council continues to work with the community to improve air quality and meet national health-based guidelines.

Regional Summary

PM₁₀and PM_2.5at towns in this region

The most significant air pollutant in New Zealand are small airborne particles in our air (known as particulate matter). Particulate pollutants are of most concern in New Zealand because of their high concentrations in some of our towns. Exposure to high levels of airborne particle pollutants has the potential to cause respiratory and cardiovascular issues. View a factsheet on why air quality is important here.

Particulate Matter (PM) are of concern in Marlborough towns. Exposure to these pollutants can have short and long term health effects. We report of annual and daily PM₁₀ and PM_2.5 concentrations each year. PM₁₀ has been measured in Blenheim since 2006, while PM_2.5 has been measured since 2017. Only trends in PM₁₀ concentrations are reported for Blenheim as this is the only site and pollutant that we have 10 or more years worth of data.

PM monitoring history at towns in this region

Annual average
Highest daily average
Exeedance

Showing:

PM₁₀

Guideline

Concentration

% of guideline

What is this showing me?

The graph shows the annual average and highest daily average PM₁₀ concentrations, and number of exceedance days for the year selected. These are shown against air quality guidelines of 20 µg/m³ for annual averages and 50 µg/m³ for daily averages. The World Health Organisation published new guidelines in September 2021 of 15 µg/m³ for annual averages and 45 µg/m³ for daily averages. Values above the guidelines can be a cause for concern as exposure to high PM₁₀ values can cause short and long term health effects. The trends in the table below indicate whether the PM₁₀ concentrations have been improving, showing no measurable change, or declining over the previous 10-years. (For towns that have more than one monitoring site, a representative site is shown).

Data table PM₁₀

Towns	10-year Trend	annual average (µg/m³)	Highest daily average (µg/m³)	2nd highest daily average (µg/m³)	Number of exceedances

PM_2.5

Guideline

Concentration

% of guideline

What is this showing me?

The graph shows the annual average and highest daily average PM_2.5 concentrations, and number of exceedance days for the year selected. These are shown against air quality guidelines of 10 µg/m³ for annual averages and 25 µg/m³ for daily averages. The World Health Organisation published new guidelines in September 2021 of 5 µg/m³ for annual averages and 15 µg/m³ for daily averages. Values above the guidelines can be a cause for concern as exposure to high PM_2.5 values can cause short and long term health effects. The trends in the table below indicate whether the PM_2.5 concentrations have been improving, showing no measurable change, or declining over the previous 10-years. (For towns that have more than one monitoring site, a representative site is shown).

Data table PM_2.5

Towns	10-year Trend	annual average (µg/m³)	Highest daily average (µg/m³)	2nd highest daily average (µg/m³)	Number of exceedances

Towns 1

Towns in the Marlborough region

Select the town you'd like to see information on by clicking the buttons below or navigate using the map.

Blenheim

1 Site