Air quality on Warminster Road shows ‘significant improvements’

Warminster Road, once known as one of the most polluted stretches of road in Wiltshire, is now showing “significant improvements” in air quality according to new data from Wiltshire Council.  

Pollution levels there now meet UK air quality standards, says the council, despite the road being plagued by the effects of heavy through-traffic on the A350. 

Monitoring from Westbury Town Council also shows that pollution levels are falling. 

The road was first declared an Air Quality Management Area (AQMA) in 2001 after exceeding the legal annual limit for nitrogen dioxide (NO₂), a harmful gas produced largely by vehicles.  

But a sustained five-year downward trend in NO₂ levels means Warminster Road could soon be removed from Wiltshire Council’s AQMA list altogether. 

Wiltshire Council Leader Cllr Ian Thorn said, “We are pleased to note that there has been a downward trend in concentrations of nitrogen dioxide in the Warminster Road over the past five years and we will continue to monitor at this location.” 

Monitoring is conducted across the county, and the council is now expanding its focus to include PM2.5 – fine air particles that are even more damaging to human health than NO₂ or another pollutant PM10. A new initiative, the Wiltshire Community Air Quality Network, will deploy 100 small sensors at pollution hotspots.  

Local support and scepticism 

The findings have been backed up by Westbury Town Council’s own monitoring programme, which operates independently of Wiltshire Council. A monitor positioned near Aldi on Warminster Road reports real-time air quality data online, with consistently low readings for both NO₂ and PM2.5. 

Cllr Mark Bailey of Westbury Town Council explained, “Because of the very heavy traffic that passes through the town, the perception of residents is that air quality must be poor – but surprisingly, our own monitors support Wiltshire Council’s claims. We measure nitrogen oxide and PM2.5, and our readings are consistently in the low range.” 

The town council’s hourly air quality readings are available to the public at: westburytowncouncil.gov.uk/dept/air-quality-monitor 

Caution urged

 Fellow Westbury town councillor Mike Sutton, though, has urged some caution, saying, “It is pleasing that the level of pollution has reduced, although what Wiltshire measure is only some of the pollutants affecting the town. We would like to know to what Wiltshire Council attributes the reduction, as traffic has certainly not reduced. There must be a reason – and that may lead to more scrutiny. 

“As one of the designated areas of poor air quality, how will Wiltshire Council determine if it deteriorates again without monitoring all relevant pollutants?” 

As part of the Wiltshire Community Air Network, members of the public, including schools, will be invited to host air quality sensors – each no bigger than a mobile phone – helping to build a clearer picture of PM2.5 levels in local communities. More information can be found at: https://www.wiltshire.gov.uk/wiltshire-community-air-network 

Pictured: the busy A350 through the centre of the town.