Air quality
Contents
TWBC has statutory duties under Part IV, Section 83 (1) of the Environment Act 1995, which requires Local Authorities to review and assess air quality within their areas. The Act sets limits, known as objectives, for a number of air pollutants. Local Authorities have a duty under the 1995 Act to designate those areas where the air quality objectives are not being met or at risk of not being met, and where people are likely to be regularly present, as Air Quality Management Areas (AQMAs). Whenever an Air Quality Management Area is declared, an Air Quality Action Plan (AQAP) describing actions by which the air quality will be brought back into compliance with the objectives, must be produced.
Annual air quality reports
TWBC is required to submit an ‘Annual Status Report’ (ASR) to DEFRA each year, in which it discusses the work it has undertaken to improve air quality in the Borough, the monitoring it has carried out and the progress it has made on delivering its AQAP. These reports are published on the ‘KentAir’ website where air quality information from other Councils across Kent can be found, together with live air quality monitoring. Here, you can also find information about air quality and health, and sign up for air quality alerts when air quality is likely to be poor.
Below are links to earlier ASRs:
Air quality objectives
The pollutant of most concern for most local authorities is nitrogen dioxide (NO2). The legislation sets two objectives for most pollutants, including NO2; a long term one and a short term one. The short term objective applies where people spend short periods of time, for example, outdoor areas such as busy shopping streets. Exceedances of the short-term objective are very rare and there are none in anywhere in Tunbridge Wells Borough.
The long term objective is based on the average level of NO2 over a full year. This applies mainly at residential property. Exceedances of this objective are quite common, and several hundred AQMAs have been declared across the country where these exceedances of this objective have occurred.
Air quality in Hawkhurst
In Tunbridge Wells Borough, we also measure particulate matter (PM10 and PM2.5) All of the current air quality objectives are met everywhere, with the exception of a small stretch of Cranbrook Road in Hawkhurst, where the annual mean objective for NO2 has been exceeded. The Council monitored at the front of the Colonnade in Hawkhurst for many years, and pollution levels there were always well below the annual mean objective. When monitoring was established in Cranbrook Road, higher levels of NO2 were found.
Specialised air quality consultants were commissioned to undertake some modelling of air quality in Hawkhurst based on air quality measurements we have taken, mainly during 2019. The results of this modelling have indicated that there may be exceedances of the annual mean objective for NO2 at about 40 properties in Cranbrook Road.
The modelling showed that, at the majority of the affected properties, any exceedance will be borderline, nevertheless, as a precautionary approach, and on the advice of the consultant, the council has taken the decision to include all 40 of the properties in the AQMA. The consultant’s report was published in the Tunbridge Wells annual air quality report (ASR) for 2020, TWBC ASR 2020.
Hawkhurst AQMA
Consequently, an AQMA was declared in this area in 2021 and the Hawkhurst AQAP was published in February 2023. The AQAP can be in the Tunbridge Wells Air Quality Action Plan.
Location of Hawkhurst AQMA: 
The main cause of elevated NO2 levels is traffic, but traffic conditions are as important as traffic volume. Pollution levels are increased where there is stop-start traffic and queuing, uphill gradients, and narrow streets with buildings on either side which prevent the pollution from dispersing and give rise to the so called ‘street canyon’ effect. At the top of Cranbrook Road all these factors are present and all contribute to the problems we have described.
Since declaring the AQMA in Hawkhurst, we have seen NO2 levels both locally and nationally decline quite rapidly. There are a number of reasons for this, which include a move away from diesel cars, increasing numbers of electric and hybrid cars, and improvements to the bus and HGV fleet with the advent of Euro VI engines. We anticipate that this downward trend will continue, and perhaps even accelerate. Therefore, in 2025, we undertook an update to the previous modelling, based on our latest monitoring in the area. This modelling has shown that all the properties in the AQMA are now compliant with the NO2 annual mean objective. Provided that NO2 levels continue to decline, or at least remain at their current levels, the TWBC will be able to consider revoking the Hawkhurst AQMA. The modelling is reported in our 2026 ASR which will be available soon.
Air quality and planning
Planning applications sometimes have to look at how the proposed development may affect the environment. Some developments may have an impact on the local air quality.
Assessments of potential air quality impacts are sometimes necessary before planning permission is granted.
Does my proposed development site cause air quality impacts?
If the development has associated traffic – potentially, yes. If the development has energy plants such as biomass or gas combined heat and power – potentially, yes.
Does my proposed development need an air quality assessment?
It depends on how much pollution may be generated and where it is situated.
Are there locations where assessments are more important?
Yes – particularly the area near the Hawkhurst AQMA.
Proposed development sites within this area which could cause air quality impacts generally need an air quality assessment alongside the planning application. Contact with the Environmental Protection Team is advised before submitting such applications to determine the level of assessment required.
What happens if the assessment shows negative impacts which would affect air quality?
Mitigation to reduce negative air quality impacts would be necessary and would need to be included in the air quality report. Those measures would then be conditioned to the planning permission if granted.
More generally air pollution levels are on a long term downward trend. There are a number of reasons for this, which include a move away from diesel cars, increasing numbers of electric and hybrid cars, and improvements to the bus and HGV fleet with the advent of Euro VI. We anticipate that this downward trend will continue, and probably even accelerate, so that, eventually, the Hawkhurst AQMA will be able to be revoked.
Planning position statement
The council's position and guidance on any new development in Hawkhurst and the surrounding area can be found in our Planning Position Statement for proposed developments which may impact on air quality in Hawkhurst document.
Other Air Quality Work
The Council is also working on two air quality projects which have been supported by grant funding from DEFRA. These are
The Pollution Patrol which includes games and activities to help children learn about air pollution.
The Clean Air Academy is primarily aimed at health professionals and has advice on how air pollution affects your health and how to stay safe.
Some documents on this page may not be in an accessible format. If you require any documents in an accessible format, please complete our online form to request them.