Air quality in Christchurch
2022 Update
Key points
• Air pollution can be an issue in Christchurch,
• In 2008 the annual average benzene
mainly during the coldest months.
concentration at the Riccarton Road
• PM
site was just over the guideline and has
10, PM2.5, NO2, SO2, CO, benzene and BaP
have been measured.
decreased since then. In 2022, the annual
average was one quarter of the guideline.
• Monitoring sites are currently located in St
Albans, Woolston and Riccarton. Historical
• CO and NO2 concentrations don’t
monitoring has occurred at other sites*.
breach the NESAQ. Annual average NO2
concentrations at the sites in Riccarton
• Monitoring sites are influenced by different
Road and St Albans have been higher than
pollutant sources. St Albans is a residential
the 2021 WHO guideline (Figure 6).
area, there are several industries in
Woolston, and Riccarton Rd is a busy,
• Annual average PM10 and PM2.5 concentrations
congested road.
measured at the St Albans site are shown
in Figure 7. In 2021, the St Albans site was
• Pollutants mainly from motor vehicles include
moved and only PM2.5 was monitored.
benzene, CO and NO2, which have been
Monitoring at the St Albans EP site started in
monitored for many years at roadside sites.
2022.
• Pollutants mainly from smoke from home
• Annual average PM10 concentrations since
heating include PM10, PM2.5 and CO.
2011 are below the AAQ guideline of
• SO
20 µg/m3.
2 comes from some industrial processes
and burning fuels like coal in industrial
• Annual average PM2.5 concentrations since
boilers. Coal used to be used for home
2016 are below the CARP guideline of
fires. With SO2 concentrations now very low,
10 µg/m3.
monitoring has stopped.
PM
PM
10
2.5
St Albans
Riccarton Rd
30
2005 WHO annual NO₂ guideline
25
40
3
NZ annual PM
20
10 guideline
3
30
g/m
µ 15
g/m
CA
C RP
R an
a nual
a lPM
guideline
µ
M 10
2.
2 5
.
guideline
₂ 20
P
5
NO
2021 WHO annual NO₂ guideline
10
0
0
1999 2002 2005 2008 2011 2014 2017 2020
1999 2003 2007
2011
2015
2019
Figure 7: Annual average PM10 and PM2.5
concentrations measured at the St Albans EP
Figure 6: Annual average NO₂ concentrations
monitoring site in 2022 and the St Albans site
measured at monitoring sites in Christchurch.
before 2021. PM2.5 monitoring started in 2011.
*www.lawa.org.nz/explore-data/canterbury-region/air-quality/christchurch/
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• Daily average PM10, PM2.5 and NO2
guideline. The updated WHO guideline is
concentrations measured during 2022 are
much less and there are many days when
shown in Figures 8, 9 and 10.
NO2 concentrations exceeded 25 µg/m3.
• There were three days in 2022 when
There have been no breaches of the NESAQ
PM
for NO2, which is for an hour average.
10 concentrations exceeded 50 µg/m3,
breaching the NESAQ.
• BaP was measured in 2003 and 2008 and
• There were 17 days in 2022 when PM
the annual average concentration was ten
2.5
concentrations exceeded 25 µg/m3. The
times the guideline.
number of days needs to reduce to zero by
• The main source of PM10, PM2.5 and BaP in
2030 to meet our CARP.
winter (when concentrations are highest) is
• Figure 10 shows the difference between
home heating.
daily average NO2 concentrations measured
• Strategies are in place to reduce emissions
at the roadside site and in a residential area.
of PM10 from home heating and these will
The concentrations do not exceed the AAQ
also lower emissions of PM2.5 and BaP.
St Albans
Riccarton Rd
Woolston
St Albans
Riccarton Rd
Woolston
75
75
3
NESAQ daily PM
3
10 guideline
50
50
g/m
g/m
µ
µ
10 25
2.5
CARP daily PM 2.5 guideline
M
25
P
M
P
0
0
Jan
Apr
Jul
Oct
Jan
Apr
Jul
Oct
Figure 8: Daily average PM10 concentrations
Figure 9: Daily average PM2.5 concentrations
measured at monitoring sites in Christchurch in
measured at monitoring sites in Christchurch in
2022.
2022.
St Albans
Riccarton Rd
The Christchurch airshed
NZ daily NO guideline
100
2
3
75
g/m
St. Albans
St. Albans EP
µ
monitoring site
monitoring site
₂ 50
NO
WHO daily NO2 guideline
25
0
Riccarton Road
monitoring site
Jan
Apr
Jul
Oct
Figure 10: Daily average NO₂ concentrations
measured at monitoring sites in Christchurch
in 2022.
See lawa.org.nz/explore-data/air-quality
to check air
pollution in Christchurch during the last few hours and
Woolston
days. You can also find more information on Environment
monitoring site
Canterbury’s air quality page ecan.govt.nz/data/air-
quality-data
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