A small village near Ely, Cambridgeshire

Traffic and Pollution

Wilburton Sign

Anyone living in or around Wilburton will know that traffic levels are high, especially during peak time. The Cambridgeshire Joint Parishes HCV Action Group contacted East Cambs District Council Environment Services in March 2016 to enquire if diffusion tubes could be deployed at a number of locations in local villages - including Wilburton. Although the group did not undertake the deployment themselves, Environment Services successfully bid for a budget to fund tubes for a seven month period from October 2016 to April 2017.

The full list of monitoring locations and details are available in the documents linked below. For Wilburton, the locations were:

  • Old School, Wilburton - roadside
  • Post Office, Wilburton - roadside
  • St Peter's Church, Wilburton - roadside

The full results are also provided in the linked documents - complete with discussion. The survey has found annual mean NO2 concentrations at all locations to be within the national air quality objective of 40µg/m³ - when an annualise mean and bias adjustment are applied.

For Wilburton, looking at the figures on an individual monthly basis, the tube near the Post Office recorded raw values of 53.6µg/m³ in December 2016, and 71.4µg/m³ in January 2017. Even with bias adjustment applied, these values are above the air quality objective.

East Cambs Environmental Services go on to conclude that air quality in Wilburton, Haddenham and Sutton is negatively impacted by road traffic emissions, especially in the winter months. The site at the Post Office has now been added to the district network of monitoring sites because there is clearly an adverse impact of traffic on air quality. This location is now designated as NAS18 - High Street, Wilburton.

Results for this site for 2017 are shown below:

Site ID Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Raw Data Bias Adjusted (0.77) and Annualised
NAS18 71.4 45 42.9 38.7 32.8 33.2 32 35.4 43.8 42.6 40.5 39.7 41.5 32.0

These show that over a 12 month monitoring period, the raw mean value is over the 40µg/m³ objective and is the second highest of all monitoring sites across the region - whilst in January 2017 Wilburton recorded the highest level of all monitoring sites in the region. The raw data reading exceeded the air quality objective in 6 months - and was close in a further 2 months.

Discussion relates the figures to winter - but it could be argued that there is a correlation between lower levels and schools holidays - when there is generally less traffic. Bias adjustment lowers the annual value to below the air quality objective so no action is required. Monitoring continues in Wilburton.

We would like to thank East Cambs District Council Environment Services for their monitoring and for allowing us this data - it is currently awaiting sign off by DEFRA. More on Air Quality monitoring can be found on the ECDC Air Quality page.

Update - the ECDC Air Quality page now includes figures for 2018 and 2019.

Update - May 2020 - with the lock down in place across the UK, measured levels of NO2 and PM2.5 across the country have fallen significantly. The BBC News reports Lockdown prompts clear fall in UK air pollution. What is noticeable from the figures given by the BBC is that the adjusted mean average figure for Wilburton in 2017 of 32 is significantly higher than mean figures for Belfast, Birmingham, Bristol, Cardiff, Glasgow and York between 2015-2019. The measurements might not be comparible like-for-like, but the adjusted mean figures are usually a good indicator.

Downloadable PDF documents:
NO2 Concentrations - Oct 2016 - April 2017
Review of supplementary NO2 monitoring - Oct 2016 - April 2017
Appendix B: Full Monthly Diffusion Tube Results for 2017