Pollution levels have exceeded health guidelines for the 11th time in Christchurch this year.
Last night, the city choked under levels of pollution nearly double those considered acceptable. The concentration of tiny airborne particles (PM10s) averaged 95 micrograms per cubic metre of air on Sunday, twice the 50mg acceptable.
By this time last year, Environment Canterbury had recorded nine days of high pollution in Christchurch.
The target for Christchurch was to breached guidelines no more than three times a year by September 2016 and only once by September 2020.
In earlier years, 4-29 days of high pollution had been recorded by June.
As well as monitoring in St Albans since 1988, numerous other suburbs have also been monitored, including Woolston since 2005.
The most polluted day in Canterbury in the last 14 years was on July 31, 2001, when a reading of 228 was recorded in St Albans.
The highest this year was 105 in Woolston on May 31.
Health guidelines have now been exceeded on the following dates in Christchurch:
February 11 - 85 in Woolston due to wind-blown dust.
February 21 - 53 in Woolston due to wind-blown dust.
May 8 - 57 in Woolston due mainly to combustion
May 29 - 52 in Woolston due mainly to combustion.
May 30 - 66 in St Albans and 69 in Woolston due mainly to combustion.
May 31 - 88 in St Albans and 105 in Woolston due mainly to combustion.
June 1 - 75 in St Albans and 61 in Woolston due mainly to combustion. June 24 - 58 in Woolston due mainly to combustion.
June 25 - 68 in Woolston due mainly to combustion.
June 29 - 62 in St Albans due mainly to combustion.
Meanwhile, last night was Rangiora's fifth night of high air pollution this year, and the third for Kaiapoi.
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