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Legal landscape: Does air quality concern equate to a moratorium on development?

Ashdown Forest

An environmental precedent set in a recent case close to Ashdown Forest has implications for housebuilding across the UK, says Mark Appleton.

Legal action taken by Wealden District Council (WDC) on environmental grounds threatens far-reaching consequences in relation to desperately neededhousebuilding projects.

WDC’s action relates only to the protection of air quality around the Ashdown Forest, but it is already affecting planning decisions in neighbouring authorities in the South East.

There is a danger that a legal precedent has been set for the way potential increases in traffic movements caused by building new homes are aggregated over wide areas and deemed detrimental to Special Areas of Conservation (SACs).

The issue arose following a case between the Secretary of State for Communities and Local Government, Knight Developments and WDC. Knight Developments’ application was not approved as the judge said fumes from additional cars would have a detrimental effect on nearby Ashdown Forest as there was no agreed heathland management scheme in place. The inspector had made mistakes so his decision was flawed.

The Design Manual for Roads and Bridges has previously stated that traffic increases along sensitive sections of road below 1,000 annual average daily traffic movements do not need to be taken into consideration.

As the joint core strategy in relation to Ashdown Forest Special Area of Conservation anticipated increases in traffic below 1,000 AADT (annual average daily traffic) along the roads adjacent to the SAC, it was thought these could be ignored. In another case, the secretary of state had argued that the 1,000 AADT threshold equated to a 1 per cent change in the critical levels relating to pollutants. If this was not exceeded, then there would be no likely significant effect on the SAC – and development should be assessed case by case. WDC argued otherwise.

"Developments will only be permitted when they can prove that they will not damage the SAC any further"

Mr Justice Jay found that on a proper interpretation, developments could not be considered in isolation. Indeed, the housing policies of the authority had already breached the threshold quoted for acceptable levels of traffic. All increases in traffic must be considered when considering a development proposal – even though the proposed development itself does not exceed the 1,000 AADT threshold.

As such, Lewes District Council and South Downs National Park Authority should, notwithstanding advice from Natural England, take into account the impact of all vehicle emissions on nitrogen deposits in the heathland within the SAC. Though relating specifically to air quality controls along the A22 and A26, the case could affect local towns such as Lewes and East Grinstead, and as far afield as Brighton and Hove. This will have disastrous effects on house building.

WDC issued a release on 7 March 2017 confirming that taking into account existing traffic and development commitments that are in place there is already an unacceptable level of nitrogen deposits in areas close to forest roads. The district council will not accept planning applications and will not grant any new planning consents that could affect the SAC.The exclusion zone could be up to 25 km.
Developments will only be permitted when they can prove that they will not damage the SAC any further. Only some types of development are exempt, such as home extensions, local shops and some brownfield land. Housing quotas cannot be met on this basis.

There are 658 designated SACs across the UK. The WDC case could be used by other local authorities or local action or environmental groups to prevent development. The case has already been referred to in the planning inspector’s observations on Leeds City Council’s Sites Allocation Plan.

WDC itself is now objecting to applications submitted to neighbouring councils on the grounds of intensification of nitrogen deposition from additional traffic movements. The minister for housing needs to be petitioned immediately to resolve this – by whatever means are necessary to prevent a potentially catastrophic effect on the housing industry.

Mark Appleton is partner, commercial property, at Boyes Turner UK

Photo | Shutterstock


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