WHAT DID WE DO IN DORKING? WHAT DID WE FIND?
We wanted to measure air pollution levels at a range of sites around Dorking during the COVID-19 lockdown period and to track changes over time as lockdown measures are eased. These results will provide the basis for corrective actions and public engagement on this critical issue.
What were the average concentrations of nitrogen dioxide, PM10 and PM2.5 particulates levels in a range of Dorking locations across April/May?
What were the average concentrations of nitrogen dioxide, PM10 and PM2.5 particulates levels in a range of Dorking locations in June?
To compare change in NO2, PM 2.5 and PM10 in those locations from April / May to June.
Nitrogen dioxide levels
There was a 14% increase in nitrogen dioxide levels across the monitored Dorking locations in the week in June, as the lockdown has begun to be eased, compared to April/May.
Specific sites in the town centre increased markedly:
Cockerel roundabout +46% 36.1 vs. 24.7 ppb (parts per billion)
High Street +30% 20.3 vs. 15.6 ppb
The highest levels of nitrogen dioxide in June were in town centre locations, other than the M25 motorway junction:
Cockerel roundabout 36.1 ppb (parts per billion)
Junction 9 M25 22.8 ppb
High Street 20.3 ppb
South Street 18.1 ppb
Vincent Lane 17.2 ppb
There was a 13% increase in PM10 levels across the monitored Dorking locations since lockdown began to be eased. This increase was primarily in out of town locations.
The highest levels of PM10 were:
Cockerel roundabout 41.3 µ/m3 (micrograms per cubic metre)
Junction 9, M25 33.5 µ/m3
Vincent Lane 29.0 µ/m3
There was a 5% increase in PM2.5 levels in the period between April and early June. As with PM10, the increase was primarily outside the town centre.
The highest levels of PM2.5 were:
Junction 9, M25 19.1 µ/m3 (micrograms per cubic metre)
Cockerel roundabout 16.4 µ/m3
Vincent Lane 16.2 µ/m3