Currently, PM10 is the only criteria air contaminant of concern in Marlborough. The graphs below show this year to date and previous years PM10 concentrations in Marlborough. Redwoodtown is monitored daily with hourly updates. Springlands is monitored one in three days. Monitoring in Picton ceased in 2010 due to the site no longer being suitable for monitoring.
Air quality 2016/17
Live information can be found on the Land Air Water Aotearoa (LAWA) website.
In accordance with regulation 16 of the Resource Management Act (National Environmental Standards relating to Certain Air Pollutants, Dioxins and Other Toxics) Regulations 2004, referred to as the NES, Marlborough District Council gives notice that the NES for PM10 has been exceeded in the Blenheim airshed as follows:
|Date of Exceedence||Location of Exceedence||PM10 (µg m-3)|
|18 July 2016||Redwoodtown||51|
|25 May 2017||Redwoodtown||52|
|15 June 2017||Redwoodtown||54|
|16 June 2017||Redwoodtown||66|
|17 June 2017||Redwoodtown||51|
|20 June 2017||Redwoodtown||74|
|21 June 2017||Redwoodtown||59|
|24 June 2017||Redwoodtown||51|
|28 June 2017||Redwoodtown||57|
|30 June 2017||Redwoodtown||61|
|3 July 2017||Redwoodtown||51|
The Marlborough District Council monitors PM10 concentrations relative to the NES at an air monitoring site in Redwoodtown. The NES for PM10 allows the threshold of 50 µg m-3 to be exceeded on no more than one day per 12 month period. The NES has been breached on ten occasions in Blenheim for 2017.
Monitoring in Marlborough
Monitoring of PM10 in Marlborough first began in 2000 in Blenheim. Monitoring has since been carried out in Picton and Renwick. Currently monitoring is carried out at two sites in Blenheim.
The National Environmental Standard (NES) for PM10 is 50μg/m3 as a 24-hour average concentration. The standards allow for only one exceedance per year. Blenheim typically exceeds the NES for PM10 3-5 times per year. The greatest number of exceedances recorded was 14. The highest concentration recorded was 85μg/m3 but typically the highest concentrations are between 55–65μg/m3. No exceedance has been recorded for Renwick and only one exceedance has been recorded for Picton.
Daily monitoring - Redwoodtown
Since 2006, PM10 has been monitored in Redwoodtown (Blenheim) every hour using a MetOne Beta Attenuation Monitor (BAM). A 24-hour average was then calculated from this data. In August 2012, the MetOne BAM was replaced with a 5014i BAM.
On high pollution days in winter, where exceedance of the NES is observed, there is typically a morning and evening peak in PM10 concentrations.
One in three day monitoring
Monitoring is carried out every one in three days at Springlands (Blenheim) using a Hi-vol monitor. Filter paper is used to collect PM10 over a 24 hour period. These filter papers are then sent to the laboratory on a monthly basis for analysis.