WAVERLEY Borough Council has been accused of misleading the Department for Environment, Food & Rural Affairs (DEFRA) over the scale of Farnham’s air quality problems.

As reported in The Herald late last month, Waverley’s latest Air Quality Annual Status Report claims air pollution - and specifically levels of nitrogen dioxide (NO2) - now only “slightly exceeds” the national objective at three monitoring stations in Farnham; two in The Borough and one in Wrecclesham Road.

However, this has been challenged this week by Farnham-based independent air quality consultant David Harvey, who believes Waverley has miscalculated its data and dramatically under-estimated the problem.

Key to Mr Harvey’s argument is the way Waverley reports its data using a ‘local bias’ factor, which is designed to counter discrepancies between the council’s monitoring equipment.

Waverley has 19 ‘diffusion tubes’ set up across Farnham to monitor levels of NO2 - 13 of which exceeded the national annual mean objective of 40 micrograms per cubic metre (µg/m3) in 2015, the most recent data released by the council.

But while these tubes are relatively cheap, they are also notoriously unreliable. So in order to improve the reliability of its readings, the council compares its data to another piece of monitoring equipment called a ‘continuous analyser’.

While costing around £100,000 to install and maintain, this continuous analyser - located at the Royal Deer crossroads - gives a much more accurate reading of NO2 levels, with which Waverley calculates a ‘local bias’ factor to correct its less reliable diffusion tube data.

The problem identified by Mr Harvey, is that the local bias factor in Waverley’s 2016 status report allows for a far greater adjustment than in previous years, and indeed than Mr Harvey himself calculates - the reasons for which Waverley is still to explain.

As a consequence, Mr Harvey believes that rather than “slightly exceeding” national objectives at just three monitoring stations across Farnham, NO2 levels are in fact breaching the legal limit at double that number.

These include the two monitoring locations previously identified by Waverley in The Borough and Wrecclesham Road - plus two additional locations in Station Hill, and one in Downing Street.

Mr Harvey, a fellow of the Institute of Air Quality Management, has subsequently dismissed Waverley’s report as “flawed” and has called on DEFRA’s external reviewer to re-assess the report.

He has also asked the council for clarification, but he been told merely that the data was calculated based on DEFRA guidance and has been accepted by the government agency.

Despite Mr Harvey’s objections, and reservations by Tory councillor Wyatt Ramsdale and opposition leader Jerry Hyman, Waverley’s executive committee accepted the 2016 Air Quality Annual Status Report at its meeting on Tuesday night.

Addressing the committee, Rowledge member Mr Ramsdale praised the executive for forming a new Air Quality Steering Group to tackle the problem, but criticised the time is has taken to publish the 2015 data and sought assurance “that the situation in Farnham, which is of great concern to me, is addressed soon”.

He added: “Personally I am especially concerned about the Wrecclesham road readings. The A325 is a busy road in my ward and is about to get a lot busier with the development of the Bordon eco-town, and is also a much used walk to school route.

“I note that not only does the average NO2 exceed the objective there, but in March 2015 the NO2 reading was over twice the objective level.

“I believe real change to air quality needs infrastructure and new vehicle technologies, and I do hope the steering group can come up with actions that are much more tangible than those reported so far.”

Farnham Residents councillor for Farnham Castle ward, Mr Hyman also welcomed the new steering group, but endorsed Mr Harvey’s observation that the council’s report has “significant flaws”, and called on Waverley to allow cross-party scrutiny of its next status report before it is submitted to DEFRA.

He added: “This is a serious matter of public health, in which the health minister [Jeremy Hunt] himself is personally involved…but nearly 10 years have been wasted [since the Farnham Air Quality Management Area (AQMA) was established in 2008].

“The report says it ‘fulfils the council’s commitment to the continuing local air quality management process’ - that is debatable, it certainly does not fulfil our obligations under Section 84 of the Environment Act which requires a genuine, scheduled and funded plan of the actions being taken to achieve the legal limits.”

Responding, Waverley’s portfolio holder for the environment James Edwards stood by the claim that there has been an overall improvement in the nitrogen dioxide levels across the borough - including the two AQMAs in Farnham and Godalming.

However, he promised more “co-ordinated action” to improve air quality, including more “tangible measures” - particularly in Farnham.

Mr Edwards said: “Given there is already a designated AQMA in Farnham, and were continued exceedances for NO2 identified in this latest report, Farnham will be a major focus on this group’s work.

“I certainly hope that with a more joined-up and action-orientated approach, we will be able to make a very real difference to air quality in Farnham and across the rest of the borough.”

The portfolio holder added the timetable for releasing the next report has been “brought forward” and should be submitted to DEFRA “within the next month, and published as soon as we have their approval”.

Responding to Mr Harvey’s comments directly, a council spokesperson said: “The 2016 Air Quality Report is a complex and technical document.

“Waverley’s expert officers did an extremely thorough and professional job to calculate the figures used in the 2016 Air Quality Report in the most accurate way, using DEFRA guidance.

“DEFRA has audited and approved the report – including all the accurate data and figures within it. It would not have been accepted by DEFRA if there was anything wrong in the document.

“If Mr Harvey disputes the accuracy of the document he should contact DEFRA with his complaints.”