Forthbank Wind Energy Development - Partnerships for Renewables

Forthbank Wind Energy Development
9.5.25 The cumulative magnitude of change is an expression of the degree to which landscape
character receptors and views will be changed by the addition of the proposed wind energy
development to wind energy developments that are already existing, consented or proposed.
This is dependent on a number of variables detailed in the table below.
Table 9.12 Cumulative Magnitude of Change
The location of the
wind energy
development in
relation to other wind
energy developments.
The extent of the
developed skyline
The number and scale
of the developments
seen simultaneously,
successively, or
sequentially.
The context in which
the wind energy
developments are
seen.
The distance of the
wind energy
development from the
viewpoint or receptor.
The magnitude of
change of the wind
energy development
as assessed in the
main assessment.
If the wind energy development is seen in a part of the view that is not affected by another
development, this will generally increase the cumulative magnitude of change as it will
extend the wind energy development influence into an area that is currently unaffected.
Conversely, if the wind energy development is seen in the context of other sites, the
cumulative magnitude of change may be lower as it is not extending development to hitherto
undeveloped parts of the outlook. This is particularly true where the scale and layout of the
wind energy development is similar to that of the other sites, as where there is a high level of
integration and cohesion with an existing site, the various wind energy developments may
appear as a single site.
If the wind energy development will add notably to the developed skyline in a view the
cumulative magnitude of change will tend to be higher, as the nature of the skyline has a
particular influence on both views and landscape receptors.
Generally, the greater the number of visible developments, the higher the cumulative
magnitude of change will be. Furthermore, the addition of the wind energy development to a
view where a greater number of smaller developments are apparent will usually generate a
higher cumulative magnitude of change than a view of one or two large developments as
this can lead to the impression of a less co-ordinated or strategic approach.
If all of the wind energy developments are seen in a similar landscape context, the
cumulative magnitude of change is likely to be lower due to visual integration and cohesion
between the sites. If wind energy developments are seen in a variety of different landscape
settings, this can lead to a perception that wind energy development is haphazard and
unplanned, affecting a wide range of landscape characters.
As in the assessment of the site itself, the greater the distance, the lower the cumulative
magnitude of change will tend to be.
The lower this is assessed to be, the lower the cumulative magnitude of change is likely to
be. Where the wind energy development itself is assessed to have a negligible magnitude of
change on a view or receptor there will not be a cumulative effect as the contribution of the
wind energy development will equate to the ‘no change’ situation.
9.5.26 Definitions of cumulative magnitude of change are applied in order that the process of
assessment is made clear in the Table 9.13 below.
Table 9.13 Significance of Cumulative Effects
High
Medium
Low
Negligible
where the addition of the wind energy development will make an immediately apparent contribution to
the cumulative situation in a landscape receptor or view, and will result in the landscape receptor or view
being perceived as a ‘wind energy development landscape’.
where the addition of the wind energy development makes a notable contribution to the cumulative
situation, and its addition is readily apparent.
where the addition of the wind energy development will make a minor contribution to the overall
cumulative situation, and its addition may be missed; and
where the addition of the wind energy development will make a negligible contribution to the cumulative
situation and its addition equates to a ‘no change’ situation.
9.5.27 There may also be intermediate levels of magnitude of change where the change falls between
two of the definitions.
Cumulative Zone of Visual Influence
9.5.28 As not all areas with potential views, have been visited, the assessment of the visual effects
have been identified using the computer aided cumulative ZTVs and wireframes. Cumulative
ZTVs are illustrated in Figures CZTV 9.1 – CZTV 9.77 within 35km and Figures CZTV 9.32 –
CZTV 9.55 in Appendix 9.11 for wind energy developments between 35km and 70km. Each
ZTV has been calculated to blade tip based on the turbine dimensions and available layouts at
November 2010 Chapter 9 Page 101
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