South Downs Local Plan: Preferred Options

Air Quality

Partnership Management Plan Outcomes and Policies

Outcome 1: The landscape character of the National Park, its special qualities and local distinctiveness have been conserved and enhanced by effectively managing land and the negative impacts of development and cumulative change.

Policy 1: Conserve and enhance the natural beauty and special qualities of the landscape and its setting, in ways that allow it to continue to evolve and become more resilient to the impacts of climate change and other pressures.

Outcome 5: Outstanding visitor experiences underpinned by a high quality access and sustainable transport network providing benefits such as health and well-being.

Policy 28: Improve and maintain rights of way and access land, to provide a better connected and accessible network for a range of abilities and users, and reduce conflict where it occurs.

Policy 29: Enhance the health and well being of residents and visitors by encouraging, supporting and developing the use of the National Park as a place for healthy outdoor activity and relaxation.


10.246 In general, air quality in the National Park is good. However, there are concerns with regard to nitrogen dioxide emissions in certain areas of concentrated and congested traffic particularly diesel vehicles, be that from cars or heavy goods vehicles (HGVs). In 2005 an Air Quality Management Area (AQMA) was declared in Lewes town centre for nitrogen dioxide[1], mainly due to emissions from traffic. There are similar AQMA designations in areas very close to the National Park boundary including Winchester Town Centre, Storrington High Street in Horsham District, and the A27 Upper Brighton Road in Worthing, where high levels of air pollutants may impact areas both outside and within the National Park.


10.247 In order to achieve the PMP outcomes particularly in regard to healthy outdoor activity it is important to ensure that further pockets of poor air quality do not become prevalent by reducing the negative impacts of development and reducing the need to travel by private car.


National Policy Context

10.248 Air quality is closely controlled by European Directives that set out statutory health-based objectives for key air pollutants that Member States are expected to achieve by certain dates. These targets have been transposed into minimum national standards for certain air pollutants, which are set out in the Air Quality Standards Regulations 2010[2].


10.249 With regard to plan making, the National Planning Policy Framework (NPPF) states that the planning system should seek to promote the conservation and enhancement of the natural environment by ‘preventing both new and existing development from contributing to or being put at unacceptable risk from, or being adversely affected by unacceptable levels of soil, air, water or noise pollution’ (paragraph 109). It goes on to say that the potential cumulative impacts of new development on both environmental and human health should be taken into account in the decision making process (paragraph 120).


Options considered and Preferred Approach

10.250 There were no specific references to air quality in the options consultation for the Local Plan.


Supporting Text

10.251 An Air Quality Action Plan (AQAP) has been produced for the Lewes town centre AQMA, including a number of measures that aim to improve air quality. It is expected that development will aid in the delivery of the AQAP by either providing measures set out in the AQAP or by funding their delivery, thereby mitigating the development’s potential negative impacts.


10.252 Applicants for development within or adjacent to an AQMA should discuss requirements with the Authority at the earliest opportunity and certainly before a planning application is submitted, to determine whether a proposed development could impact upon the AQMA and therefore require mitigation measures.


10.253 The effects of air pollution can be felt far beyond the original source of the pollution and impact other areas. Therefore all proposals, not just those for development within or adjacent to AQMAs need to consider the potential impact on air quality.

Development Management Policy SD58: Air Quality


1. The Authority, working with local authority partners and other relevant agencies will seek to improve air quality throughout the National Park. Development proposals that may lead to a significant deterioration in local air quality resulting in unacceptable effects on human health, the natural environment or local amenity, will require the submission of an air quality assessment, which should address:

a) The existing background levels of air quality;

b) The cumulative impact of development levels of air quality; and

c) The feasibility of any measures of mitigation that would prevent the national air quality objectives being exceeded, or would reduce the extent of the air quality deterioration.


2. Development proposals that by virtue of their location, nature or scale could impact on an AQMA will be required to:

a) Have regard to any relevant AQAP and to seek improvements in air quality through implementation of measures in the AQAP; and

b) Provide mitigation measures where the development and/or associated traffic would adversely affect any declared AQMA.


3. Development proposals that comply with other relevant policies, will be permitted where they:

a) Provide mitigation measures where the development and/or its associated traffic could lead to a declaration of a new or extended AQMA,

b) Ensure that the development will not have a negative impact on the surrounding area in terms of its effect on health, the natural environment or general amenity, taking into account cumulative impacts,

c) Promote opportunities for walking, cycling and public transport and congestion management to reduce traffic levels in areas of reduced air quality, particularly in town or village centre locations, and promote the opportunity for cycling through the provision of cycleways, and

d) Secure best practice methods to reduce levels of dust and other pollutants arising from the construction of development and/or from the use of the completed development.

Evidence and Background Documents

[1]    Declaration of an AQMA is necessary under Part 4 of the Environment Act 1995, when certain statutory air quality thresholds are breached.

[2]    Air Quality Standards Regulations (2010) For nitrogen dioxide there are two targets. That the level not to exceed 200μg.m-3 more than 18 times a year (1 hour mean) something which is not currently an issue in Lewes. And that the annual mean should not exceed 40μg.m-3 – currently exceeded in Lewes town centre, causing the AQMA to be declared.