DRAFT Sustainability Appraisal Report for the Emerging Local Plan ...

The dispersion software used to model future concentrations assume large
reductions in emissions in future years associated with cleaner vehicles – so even
with a large increase in vehicle numbers developers can still report an improvement
in air quality.
Developers do not take into account the cumulative impacts of other proposed (or
already permitted) developments for the area.
As there is no official national guidance on determining the significance of air quality
impacts, describing significance remains an issue of contention. For instance,
developers can interpret increases in concentrations of up to 0.4 µg/m 3 as
imperceptible or negligible following Development Control: Planning For Air Quality
(2010 Update).
9.107 As it is assumed that every development will add to overall air emissions, be it emissions from
buildings or additional traffic, it is proposed that every new development meeting the CIL’s
definition of a dwelling is required to contribute towards the cost of tackling poor air quality.
These financial contributions secured through Community Infrastructure Levy (CIL) would be
then spent on offsetting measures (as listed in Appendix 15).
9.108 In addition, to minimise site‐specific direct emissions from new developments and reduce
exposure of new residents to poor air quality, developers will be required to implement
redesign and mitigation measures according to the magnitude of impacts and existing
pollutant concentrations at the development site. The assumed scale of impact was related to
the predicted increase in car numbers and based on the study of available guidance
documents – listed in Table 2 of Appendix 15.
9.109 Small development of up to 10 units to be located at sites where air pollutant levels are close
to or exceeding objectives can be required to make improvements to the development design
and layout (redesign measures in Appendix 15), for example, ensure that at busy roads
appropriate distance is maintained between the building and the road; place sensitive uses
(bedrooms, children play areas) in the least polluted parts of the site; limit car parking spaces;
provide cycling facilities (e.g. shelters) and look into improving building insulation (above
current regulations) and/or increasing the proportion of energy generated from renewable
sources (above current regulations). Small developments in background locations where
current air pollution levels remain well below objectives can still be required to look into
design improvements and, for example, provide shelters for bicycles and improve building
thermo efficiency. These design improvements will be secured through planning conditions.
9.110 The direct impact of slightly larger developments of 11‐50 units is also considered to be low;
however, if located at sites of relatively poor air quality, they may be required to make
changes to design and layout (similar to small developments). They could also use some of
the mitigation measures in Appendix 15 to encourage sustainable modes of transport, for
example, by providing new residents with information of public transport, routes/times and
walking and cycling routes. Mitigation measures will be secured through planning obligations.
9.111 It is assumed that developments of 50‐100 units will have the potential for a low to medium
impact on air quality, depending on the existing pollutant concentrations in the area. It is
suggested that higher adverse impact of these development is managed by a broader range
of redesign and mitigation measures. In addition to the measures described above for smaller
developments, the measures to be applied by larger developments could, for example,
include reduced parking provision and /or preference given to low emission / car club
vehicles and improvements to traffic management or road layout at the development site.
9.112 Unless proven otherwise, potentially significant adverse air quality impacts of developments
of a size above 100 units will be presumed. Developers will be required to use a broad range
of redesign and mitigation measures. Redesign measures to be considered by large
developments include walking and cycling routes/facilities; provision of facilities for public
transport, such as bus stops and lay‐bys, communal combined heat and power and improved
building insulation (above current regulations). Part L of the Building Regulations identifies
the legal minimum a development needs to meet in terms of energy efficiency in the UK. The
Council could introduce more stringent demands for larger developments. In addition, a
Page | 137 Runnymede BC FINAL Sustainability Appraisal Report – Feb 2013