1.7. Assessing seascape/landscape effects

1.7.1.    Interface between SLVIA and Onshore LVIA

  1. Together, the SLVIA and the onshore Landscape and Visual Impact Assessment (LVIA) provide a whole project assessment of the effects of the Project. The offshore elements of the Project (the Proposed Development) are assessed in the SLVIA and the onshore elements of the Project (the onshore substation, onshore cable corridor, and landfall location) are assessed in the LVIA.  Both the SLVIA and the LVIA follow a broadly similar assessment methodology that uses the same glossary and terminology.
  2. The SLVIA also provides an assessment of the cumulative effects likely to result from any areas where the construction, operation and decommissioning of the offshore and onshore elements combine to affect receptors within the SLVIA study area. An example could include effects on views where both offshore and onshore elements are visible, potentially resulting in cumulative landscape and visual effects as a result of the construction, operation and decommissioning of the offshore and onshore elements. These are assessed as part of the Tier 1 Cumulative Effects Assessment in Chapter 15 (Section 15.12).
  3. The SLVIA study area includes the intertidal area and this area is also considered as part of the onshore LVIA study area. The intertidal area at the proposed landfall incorporates the rock platform and shingle beach west of Chapel Point. As trenchless technology (e.g. horizontal directional drilling (HDD)) will be employed to bring the offshore export cable ashore, no physical disturbance of the beach or intertidal area is predicted.

1.7.2.    Approach to Assessment of Seascape and Landscape Effects

  1. The Marine Policy Statement (MPS) (UK Government, 2011) states “references to seascape should be taken as meaning landscapes with views of the coast or seas, and coasts and the adjacent marine environment with cultural, historical and archaeological links with each other.”
  2. In England, seascape characterisation includes both the sea surface and what lies below the waterline, however in Scotland, ‘the focus is on the coast and its interaction with the sea and hinterland, relationships that are quite distinctive in the Scottish context’ (NatureScot, 2018).
  3. Given the definition in the MPS and the NatureScot coastal character assessment guidance, the assessment of seascape character effects in this SLVIA focuses on areas of onshore landscape with views of the coast or seas/marine environment, in other words the ‘coastal character’, on the premise that the most important effect of offshore wind farms is on the perception of the character of the coast.
  4. Coastal character is the ‘distinct, recognisable and consistent pattern of elements on the coast, land and sea that makes one part of the coast different from another’ (NatureScot, 2018) and is made up of the margin of the coastal edge, its immediate hinterland and areas of sea.
  5. The extent of the coast is principally influenced by the dominance of the sea in terms of physical characteristics, views and experience. The landward extent of the coast can be narrow where edged by cliffs or settlement; or broad where it includes raised beaches, dunes or more open coastal pasture or machair. The major determinant in defining the landward and seaward components of the coast is the sea - the key characteristic.
  6. Regional Coastal Character Areas (CCAs) are appropriate for the assessment of effects on coastal character. The coastal character of the SLVIA study area within Scotland is defined at the regional level within the Regional Seascape Character Assessment Aberdeen to Holy Island Suffolk (Forth and Tay Offshore Windfarm Developer Group, 2011).
  7. The Regional Seascape Character Areas defined in the FTOWDG Seascape Character Assessment are considered to equate to Regional CCAs as defined in the subsequent NatureScot Coastal Character Assessment Guidance (NatureScot, 2018) i.e. recognisable geographical areas with a consistent overall character at a strategic scale. Regional CCAs are shown as a simple colour line along the coast (Figure 15.3).
  8. Due to its scale, distance from shore and extent of visibility, it is necessary to consider the effects of the Proposed Development on both coastal character and landscape character.
  9. The effect of the Proposed Development on coastal (seascape) character is considered within the boundaries of defined coastal character areas (CCAs) and the immediately adjacent landscape character type (LCT) covering its hinterland, as defined in Figure 15.3, where there is a strong visual relationship with the sea/tidal waters and coastal landscapes such as dunes or cliffs.
  10. The effect of the Proposed Development on landscape character is considered on LCTs outside and inland of these CCAs and coastal LCTs, where there may be some intervisibility of the Proposed Development, but where the land is unlikely to have a strong visual relationship with the sea/tidal waters. These LCTs are identified in Figure 15.3 In general they are considered unlikely to experience significant character effects as a result of the Proposed Development because it is located in the sea, and these landscapes do not have a strong visual relationship with the sea and their character is fundamentally defined by other characteristics.
  11. Where detailed assessment of CCAs is required, effects are assessed on the discrete aspects of coastal character as defined in the coastal character assessment guidance (NatureScot, 2018) follows:
  • Maritime influences and experience from the sea,
  • Character of the coastal edge and its immediate hinterland,
  • Extent of human activity, and
  • Views and visibility (visual assessment).
    1. The assessment of effects on coastal character focuses upon the experiential characteristics that may be affected by the Proposed Development, rather than physical characteristics (which will not be affected by offshore development).

1.7.3.    Seascape / landscape effects

  1. In respect of the Proposed Development, the potential seascape/landscape effects, occurring during the construction, operation and decommissioning periods of the Proposed Development may therefore include, but are not restricted to the following:
  • changes to coastal character / landscape character and qualities: coastal/landscape character may be affected through the incremental effect on the perception of characteristic elements, landscape patterns and qualities (including experiential characteristics) and the addition of new features, the magnitude of which is sufficient to alter the perceived coastal character / landscape character within a particular area.
  • changes to the perceived character of designated landscapes: that will affect the perceived special landscape qualities underpinning the designation and potentially its integrity.
  • cumulative effects on coastal character / landscape character: where more than one development of a similar type may lead to a cumulative effect on the perception of coastal character or landscape character.
    1. Effects on coastal character and landscape character arising from the Proposed Development will be indirect effects, which will be perceived from the wider landscape, outside the Proposed Development array area.

Evaluating seascape/landscape sensitivity to change

  1. The assessment of sensitivity takes account of the seascape / landscape value and the susceptibility of the receptor to the Proposed Development. 
  2. Seascape/landscape sensitivity often varies in response to both the type and phase of the development proposed and its location, such that sensitivity needs to be considered on a case by case basis.  It should not be confused with ‘inherent sensitivity’ where areas of the landscape may be referred to as inherently of ‘high’ or ‘low’ sensitivity.  For example, a National Park may be described as inherently of high sensitivity on account of its designation and value, although it may prove to be less susceptible (and therefore sensitive) to a particular development. The susceptibility of seascape/landscape receptors has been assessed in relation to change arising from the specific development proposed.

Sensitivity of seascape/landscape receptor

  1. The sensitivity of a seascape/landscape character receptor is an expression of the combination of the judgements made about the susceptibility of the receptor to the specific type of change or the development proposed, and the value related to that receptor.
Value of the seascape/landscape receptor
  1. The value of a seascape/landscape character receptor is a reflection of the value that society attaches to that seascape/landscape. The assessment of the seascape/landscape value has been classified as high, medium-high, medium, medium-low or low and the basis for this assessment has been made clear using evidence and professional judgement, based on the following range of factors.
  • Seascape/landscape designations - A receptor that lies within the boundary of a recognised landscape related planning designation will be of increased value, depending on the proportion of the receptor that is affected and the level of importance of the designation which may be international, national, regional or local. The absence of designations does not however preclude value, as an undesignated landscape character receptor may be valued as a resource in the local or immediate environment.
  • Seascape/landscape quality - The quality of a seascape/landscape character receptor is a reflection of its attributes, such as scenic quality, sense of place, rarity and representativeness and the extent to which its valued attributes have remained intact. A seascape/landscape with consistent, intact, well-defined and distinctive attributes is considered to be of higher quality and, in turn, higher value, than a landscape where the introduction of elements has detracted from its character.
  • Seascape/landscape experience - The experiential qualities that can be evoked by a landscape receptor can add to its value and relates to a number of factors including the perceptual responses it evokes, the cultural associations that may exist in literature or history, or the iconic status of the seascape/landscape in its own right, the recreational value of the seascape/landscape, and the contribution of other values relating to the nature conservation or archaeology of the area.
Seascape / landscape susceptibility to change
  1. The susceptibility of a seascape/landscape character receptor to change is a reflection of its ability to accommodate the changes that will occur as a result of the addition of the Proposed Development without undue consequences for the maintenance of the baseline situation and/or the achievement of landscape planning policies and strategies. Some landscape receptors are better able to accommodate development than others due to certain characteristics that are indicative of capacity to accommodate change. These characteristics may or not also be special landscape qualities that underpin designated landscapes.
  2. The assessment of the susceptibility of the seascape/landscape receptor to change has been classified as high, medium-high, medium, medium-low or low and the basis for this assessment has been made clear using evidence and professional judgement. Indicators of landscape susceptibility to the type of development proposed (construction, operation and decommissioning of the Proposed Development) are based on the following criteria.
  • Overall strength and robustness: Collectively the overall characteristics and qualities of a particular seascape/landscape result in a strong and robust landscape that is capable of reasonably accommodating the influence of the Proposed Development without undue adverse effects on the special landscape qualities (in the case of a designated landscape) or the key characteristics for which an area of seascape/landscape character or a particular element it is valued.
  • Landscape scale and topography: The scale and topography are large enough to physically accommodate the influence of the Proposed Development. Topographical features such as more complex, distinctive or small-scale coastal landforms are likely to be more susceptible than simple, broad and homogenous coastal landforms.
  • Openness and enclosure: Openness in the seascape/landscape may increase susceptibility to change because it can result in wider visibility, however open seascape/landscape may also be larger scale and simple, which will decrease susceptibility. Conversely, enclosed seascape/landscapes can offer more screening potential, limiting visibility to a smaller area, however they may also be smaller scale and more complex which will increase susceptibility. In general, large scale, simple and open seascapes/coastlines are likely to be less susceptible to the Proposed Development than more enclosed, complex seascapes/coasts (such as indented bays, headlands etc).
  • Skyline: Prominent and distinctive skylines and horizons with important landmark features that are identified in the landscape character assessment, are generally considered to be more susceptible to development in comparison to broad, simple skylines which lack landmark features or contain other infrastructure features.
  • Relationship with other development and landmarks: Contemporary landscapes where there are existing similar developments (WTGs or energy developments) or other forms of development (industry, mineral extraction, masts, urban fringe/large settlement, major transport routes) that already have a characterising influence result in a lower susceptible to development in comparison to areas characterised by smaller scale, historic development and landmarks.
  • Perceptual qualities: Notable landscapes that are acknowledged to be particularly scenic, wild or tranquil are generally considered to be more susceptible to development in comparison to ordinary, cultivated or farmed / developed landscapes where perceptions of ‘wildness’ and tranquillity are less tangible. Landscapes which are either remote or appear natural may vary in their susceptibility to development.
  • Landscape context and association: the extent to which the Proposed Development will influence the character of seascape/landscape receptors across the study area relates to the associations that exist between the seascape/landscape receptor within which the Proposed Development are located and the seascape/landscape receptor from which the Proposed Development is being experienced. In some situations this association will be strong, i.e., where the seascapes/landscapes are directly related, and in other situations weak (where the landscape association is weak). The context and visual connection to areas of adjacent seascape/landscape character or designations has a bearing on the susceptibility to development.
Seascape/landscape sensitivity rating
  1. An overall sensitivity assessment of the seascape/landscape receptor has been made by combining the assessment of the value of the seascape/landscape character receptor and its susceptibility to change. The evaluation of seascape/landscape sensitivity has been applied for each seascape/landscape receptor - high, medium-high, medium, medium-low and low - by combining individual assessments of the value of the receptor and its susceptibility to change. The basis for the assessments has been made clear using evidence and professional judgement in the evaluation of sensitivity for each receptor. Criteria that tend towards higher or lower sensitivity are set out in Table 1.8   Open ▸ below.
Table 1.8:
Seascape/Landscape Sensitivity to Change

Table 1.8: Seascape/Landscape Sensitivity to Change

1.7.4.    Seascape/landscape magnitude of change

  1. The magnitude of change on seascape/landscape receptors is an expression of the scale of the change that will result from the Proposed Development and is dependent on a number of variables regarding the size or scale of the change. The consideration of the size or scale of the effect, its geographical extent and its duration and reversibility are kept separate, by basing the magnitude of change primarily on size or scale to determine where significant and non-significant effects occur, and then describing the geographical extents of these effects and their duration and reversibility separately.

Size or scale of change

  1. This criterion relates to the size or scale of change to the seascape/landscape that will arise as a result of the Proposed Development, based on the following factors.
  • Seascape/landscape elements: The degree to which the pattern of elements that makes up the seascape/landscape character will be altered by the Proposed Development, by removal or addition of elements in the seascape/landscape. The magnitude of change will generally be higher if the features that make up the seascape/landscape character are extensively removed or altered, and/or if many new offshore elements are added to the seascape/landscape.
  • Seascape/landscape characteristics: This relates to the extent to which the effect of the Proposed Development changes, physically or perceptually, the key characteristics of the seascape/landscape that may be important to its distinctive character. This may include, for example, the scale of the landform, its relative simplicity or irregularity, the nature of the seascape/landscape context, the grain or orientation of the seascape/landscape, the degree to which the receptor is influenced by external features and the juxtaposition of the Proposed Development in relation to these key characteristics. If the Proposed Development are located in a seascape/landscape receptor that is already affected by other similar development, this may reduce the magnitude of change if there is a high level of integration and the developments form a unified and cohesive feature in the seascape/landscape.
  • Seascape/landscape designation: In the case of designated landscapes, the degree of change is considered in light of the effects on the special landscape qualities which underpin the designation and the effect on the integrity of the designation. All landscapes change over time and much of that change is managed or planned.  Often landscapes will have management objectives for ‘protection’ or ‘accommodation’ of development. The scale of change may be localised, or occurring over parts of an area, or more widespread affecting whole landscape receptors and their overall integrity.
  • Distance: The size and scale of change is also strongly influenced by the proximity of the Proposed Development to the receptor and the extent to which the development can be seen as a characterising influence on the landscape. Consequently, the scale or magnitude of change is likely to be lower in respect of landscape receptors that are distant from the Proposed Development and / or screened by intervening landform, vegetation and built form to the extent that the scale of their influence on landscape receptors is small or limited. Conversely, landscapes closest to the development are likely to be most affected. Host landscapes (where the development is located within a ‘host’ landscape character unit) will be directly affected whilst adjacent areas of landscape character will be indirectly affected.
  • Amount and nature of change: The amount of the Proposed Development that will be seen. Visibility of the Proposed Development may range from one WTG blade tip to all of the WTGs; generally, the greater the amount of the Proposed Development that can be seen, the higher the scale of change. The degree to which the Proposed Development is perceived to be on the horizon or ‘within’ the seascape/landscape. Generally, the magnitude of change is likely to be lower if the Proposed Development is largely perceived to be on the horizon at distance, rather than ‘within’ the seascape/landscape.

Geographical extent

  1. The geographic extent over which the seascape/landscape effects has been experienced is also assessed, which is distinct from the size or scale of effect. This evaluation is not combined in the assessment of the level of magnitude, but instead expresses the extent of the receptor that will experience a particular magnitude of change and therefore the geographical extents of the significant and non-significant effects.
  2. The extent of the effects will vary depending on the specific nature of the Proposed Development and is principally assessed through analysis of the extent of perceived changes to the seascape/landscape character through visibility of the Proposed Development.
  3. Landscape effects are described in terms of the geographical extent or physical area that will be affected (described as a linear or area measurement). This should not be confused with the scale of the development or its physical footprint. The manner in which the geographical extent of the seascape/landscape effect is described for different seascape/landscape receptors is explained as follows.
  • Seascape/landscape character: The extent of the effects on seascape/landscape character will vary depending on the specific nature of the Proposed Development. This is not simply an expression of visibility or the extent of the ZTV, but also includes a specific assessment of the extent of landscape character that will be changed by the Proposed Development in terms of its character, key characteristics and elements. 
  • Landscape Designations: In the case of a designated landscape, this refers to the extent the special landscape qualities of the designation are affected and whether this can be defined in terms of area or linear measurements, or subjectively through professional judgement (with the support of an expert topic group and / or peer review) and whether the integrity of the designation is affected.

Duration and reversibility

  1. The duration and reversibility of seascape/landscape effects has been based on the period over which Proposed Development are likely to exist (during construction and operation) and the extent to which these elements has been removed (during decommissioning) and its effects reversed at the end of that period. Long-term, medium-term and short-term seascape/landscape effects are defined as follows:
  • long-term – more than 10 years (may be defined as permanent or reversible);
  • medium-term – 6 to 10 years; and
  • short-term – 1 to 5 years.

1.7.5.    Seascape/landscape magnitude of change rating

  1. The ‘magnitude’ or ‘degree of change’ resulting from the Proposed Development is described as ‘High’, ‘High-medium’, ‘Medium’, ‘Medium-low’ ‘Low’ or ‘Negligible’. In assessing magnitude of change, the assessment focuses on the size or scale of change. The geographic extent, duration and reversibility are stated separately in relation to the assessed effects (i.e., as short/medium / long-term and temporary/permanent). The basis for the assessment of magnitude for each receptor has been made clear using evidence and professional judgement. The levels of magnitude of change that can occur are defined in Table 1.9   Open ▸ .
Table 1.9:
Seascape/Landscape Magnitude of Change Ratings

Table 1.9: Seascape/Landscape Magnitude of Change Ratings

1.7.6.    Evaluating seascape/landscape effects and significance

  1. The level of seascape/landscape effect is evaluated through the combination of seascape/landscape sensitivity and magnitude of change. Once the level of effect has been assessed, a judgement is then made as to whether the level of effect is ‘significant’ or ‘not significant’ as required by the relevant EIA Regulations. This process is assisted by the matrix in Table 1.10   Open ▸ which is used to guide the assessment. The factors considered in the evaluation of the sensitivity and the magnitude of the change resulting from the Proposed Development and their conclusion, has been presented in a comprehensive, clear and transparent manner.
  2. Further information is also provided about the nature of the effects (whether these will be direct/indirect; temporary/permanent/reversible; beneficial/neutral/adverse or cumulative).
  3. A significant effect will occur where the combination of the variables results in the Proposed Development having a defining effect on the seascape/landscape receptor, or where changes of a lower magnitude affect a seascape/landscape receptor that is of particularly high sensitivity. A major loss or irreversible effect over an extensive area or seascape/landscape character, affecting landscape elements, characteristics and / or perceptual aspects that are key to a nationally valued landscape are likely to be significant.
  4. A non-significant effect will occur where the effect of the Proposed Development is not defining, and the landscape character of the receptor continues to be characterised principally by its baseline characteristics. Equally a small-scale change experienced by a receptor of high sensitivity may not significantly affect the special landscape quality or integrity of a designation. Reversible effects, on elements, characteristics and character that are of small-scale or affecting lower value receptors are unlikely to be significant.

1.8. Evaluation of significance

  1. The significance of the effect upon seascape, landscape and visual receptors is determined by correlating the magnitude of the impact and the sensitivity of the receptor, as presented in Table 1.10   Open ▸ .
  2. The significance of the effect on each seascape/landscape character and visual receptor is dependent on all of the factors considered in the sensitivity of the receptor and the magnitude of change resulting from the Proposed Development. Factors which influence levels of sensitivity and magnitude of change assessed in the SLVIA are set out in full in Volume 3 Technical Appendix 13.1: SLVIA Methodology. Judgements on sensitivity and magnitude of change are combined to arrive at an overall assessment as to whether the Proposed Development will have an effect that is significant or not significant on each seascape/ landscape and visual receptor.
  3. The matrix in Table 1.10   Open ▸ is used as a guide to help inform the threshold of significance when combining sensitivity and magnitude to assess significance. On this basis potential impacts are assessed as of negligible, minor, moderate and major. In those instances where there would be no effect, the magnitude has been recorded as ‘Zero’ and the level of effect as ‘None’.
  4. For the purposes of this assessment, any effects with a significance level of major and major/moderate have been deemed significant in EIA terms (dark shaded boxed in Table 1.10   Open ▸ ). ‘Moderate’ levels of effect (indicated in mid-grey in Table 1.10   Open ▸ ) have the potential, subject to the assessor’s professional judgement, to be considered as significant or not significant, depending on the sensitivity and magnitude of change factors evaluated. These assessments are explained as part of the assessment, where they occur.
  5. Significance can therefore occur at a range of levels depending on the magnitude and sensitivity, however in all cases, a significant effect is considered more likely to occur where a combination of the variables results in the Proposed Development having a defining effect on the landscape/seascape character or view. Definitions are not provided for the individual categories of significance shown in the matrix and the reader should refer to the detailed definitions provided for the factors that combine to inform sensitivity and magnitude. Effects assessed as being either moderate/minor, minor, minor/negligible or negligible level are assessed as non-significant (light shaded boxes in Table 1.10   Open ▸ ).
  6. In line with the emphasis placed in GLVIA3 upon the application of professional judgement, an overly mechanistic reliance upon a matrix is avoided through the provision of clear and accessible narrative explanations of the rationale underlying the assessment made for each landscape and visual receptor.
Table 1.10:
Impact Significant Matrix

Table 1.10: Impact Significant Matrix

 

1.9. Nature of effects

1.9.1.    Overview

  1. The nature of effects refers to whether the landscape and/or visual effect of the Proposed Development is positive or negative (herein referred to as ‘beneficial’ and ‘adverse’).
  2. The EIA Regulations 2017 state that the ES should define ‘the direct effects and any indirect, secondary, cumulative, transboundary, short-term, medium-term and long-term, permanent and temporary, positive and negative effects of the development’.
  3. Cumulative effects have been described in Section 13.10, and ‘short-term, medium-term and long-term, permanent and temporary’ effects are described in Section 13.5 and 13.6 under the heading ‘Duration of Effect’. Transboundary effects are relevant only to the SLVIA and concern the overlap of the SLVIA 50 km study area with EU maritime waters.

1.9.2.    Direct and indirect effects

  1. Direct landscape effects relate to the host landscape and concern both physical and perceptual effects on the receptor.
  2. Indirect landscape effects relate to those landscapes and receptors which separated by distance or remote from the development and therefore are only affected in terms of perceptual effects. The Landscape Institute also defines indirect effects as those which are not a direct result of the development but are often produced away from it or as a result of a complex pathway. 
  3. Visual effects are considered as direct effects, as the view itself may be directly altered by the Proposed Development.

1.9.3.    Positive and negative effects

  1. Guidance provided by the in GLVIA3 on the nature of effect (i.e., beneficial or adverse) states that ‘in the LVIA, thought must be given to whether the likely significant landscape and visual effects are judged to be positive (beneficial) or negative (adverse) in their consequences for landscape or for views and visual amenity’, but it does not provide guidance as to how that may be established in practice. The nature of effect is therefore one that requires interpretation and, where applied, this involves reasoned professional opinion.
  2. In this assessment the nature of effects refers to whether the landscape and/or visual effect of the Proposed Development is positive or negative (herein referred to as ‘beneficial’/‘neutral’ or ‘adverse’).
  3. In relation to many forms of development, SLVIA will identify ‘beneficial’ and ‘adverse’ effects by assessing these under the term ‘Nature of Effect’. The seascape, landscape and visual effects of wind farms are difficult to categorise in either of these brackets as, unlike other disciplines, there are no definitive criteria by which the effects of wind farms can be measured as being categorically ‘beneficial’ or ‘adverse’. In some disciplines, such as noise or ecology, it is possible to quantify the effect of a wind farm in numeric terms, by objectively identifying or quantifying the proportion of a receptor that is affected and assessing the nature of that effect in justifiable terms. However, this is not the case in relation to landscape and visual effects where the approach combines quantitative and qualitative assessment.
  4. Generally, in the development of ‘new’ wind farms, a precautionary approach has been adopted, which assumes that significant landscape and visual effects are weighed on the adverse side of the planning balance. Unless it is stated otherwise, the effects considered in the assessment have been considered to be adverse. Beneficial or neutral effects may, however, arise in certain situations and are stated in the assessment where relevant.  The following definitions have been used.
  • Beneficial effects - contribute to the seascape, landscape and visual resource through the enhancement of desirable characteristics or the introduction of new, beneficial attributes. The development contributes to the landscape by virtue of good design or the introduction of new landscape planting. The removal of undesirable existing elements or characteristics can also be beneficial, as can their replacement with more appropriate components.
  • Neutral effects - occur where the Proposed Development fits with the existing seascape/landscape character or visual amenity. The development neither contributes to nor detracts from the landscape and visual resource and can be accommodated with neither beneficial or adverse effects, nor where the effects are so limited that the change is hardly noticeable. A change to the seascape, landscape and visual resource is not considered to be adverse simply because it constitutes an alteration to the existing situation.
  • Adverse effects - are those that detract from the seascape/landscape character or quality of visual attributes experienced, through the introduction of elements that contrast, in a detrimental way, with the existing characteristics of the seascape, landscape and visual resource, or through the removal of elements that are key in its characterisation.

1.10. Assessing cumulative seascape, landscape and visual effects

1.10.1.              Methodology

Approach to Additional or Combined Cumulative Effects

  1. The Cumulative Effects Assessment (CEA) takes into account the impact associated with the Proposed Development together with other relevant plans, projects and activities. Cumulative effects are therefore the additional or combined effect of the Proposed Development in combination with the effects from a number of different projects, on the same receptor or resource. Please see volume 1, chapter 6 for detail on CEA methodology.
  2. GLVIA3 (Landscape Institute and IEMA 2013, p120) defines cumulative landscape and visual effects as those that ‘result from additional changes to the landscape and visual amenity caused by the proposal in conjunction with other developments (associated with or separate to it), or actions that occurred in the past, present or are likely to occur in the foreseeable future.’
  3. NatureScot’s guidance, Assessing the Cumulative Impact of Onshore Wind Energy Developments (NatureScot, 2021) is widely used across the UK to inform the specific assessment of the cumulative effects of windfarms. Both GLVIA3 and NatureScot’s guidance provide the basis for the methodology for the cumulative SLVIA undertaken in the SLVIA. The NatureScot (2021) guidance defines:

Tiered Approach to CEA

  1. In accordance with NatureScot guidance and GLVIA3 (para 7.13), existing projects and those which are under construction are included in the SLVIA baseline and described as part of the baseline conditions, including the extent to which these have altered character and views, and affected sensitivity to windfarm development. An assessment of the additional effect of the Proposed Development is undertaken in conjunction with a baseline that includes operational and under-construction projects as part of the main assessment in Chapter 15, Section 15.11 Assessment of Significance. This includes assessment of the Proposed Development against magnitude factors such as its size, scale, spread and landscape context, as well as cumulative effect factors relating to the operational and under-construction wind farms, such as its increase in spread, aesthetic relationship, and contrasts of size and spacing of turbines of the projects.
  2. A further assessment of the additional cumulative seascape, landscape and visual effects of the Proposed Development with other potential future projects is undertaken in Chapter 15, Section 15.12 Cumulative Effects Assessment (CEA).
  3. In undertaking this CEA for the Proposed Development, it is important to bear in mind that other projects and plans under consideration will have differing potential for proceeding to an operational stage and hence a differing potential to ultimately contribute to a cumulative impact alongside the Proposed Development. Therefore, a tiered approach has be adopted. This provides a framework for placing relative weight upon the potential for each project/plan to be included in the CEA to ultimately be realised, based upon the project/plan’s current stage of maturity and certainty in the projects’ parameters. The tiered approach which will be utilised within the Proposed Development CEA employs the following tiers:
  • tier 1 assessment – Proposed Development (Berwick Bank Wind Farm offshore) with Berwick Bank Wind Farm onshore (whole project effect assessment);
  • tier 2 assessment – All plans/projects assessed under Tier 1, plus projects with consent and submitted but not yet determined;
  • tier 3 assessment – All plans/projects assessed under Tier 2, plus those projects with a Scoping Report; and
  • tier 4 assessment – All plans/projects assessed under Tier 3, plus those projects likely to come forward where an Agreement for Lease (AfL) has been granted.
    1. This tiered approach has been adopted to provide an explicit assessment of the Proposed Development as a whole.
    2. The projects and plans selected as relevant to the CEA presented within this chapter are based upon the results of a screening exercise (see volume 3, appendix 6.3 of the Offshore EIA Report). Each project or plan has been considered on a case by case basis for screening in or out of this chapter's assessment based upon data confidence, effect-receptor pathways and the spatial/temporal scales involved. A comprehensive ‘long list’ of projects was reviewed, and projects within the cumulative search area base plan compiled within the 60 km SLVIA study area (Figure 15.16), with potential for cumulative impact interactions. The specific projects scoped into the CEA for seascape, landscape and visual receptors, are set out in Chapter 15.
    3. The range of potential cumulative effects that are identified and included in the CEA, is a subset of those considered for the Proposed Development alone assessment. This is because some of the potential impacts identified and assessed for the Proposed Development alone, are localised and temporary in nature. It is considered therefore, that these potential impacts have limited or no potential to interact with similar changes associated with other plans or projects. These have therefore been scoped out of the cumulative effects assessment.
    4. Similarly, some of the potential impacts considered within the Proposed Development alone assessment are specific to a particular phase of development (e.g. construction, operation and maintenance or decommissioning). Where the potential for cumulative effects with other plans or projects only have potential to occur where there is spatial or temporal overlap with the Proposed Development during certain phases of development, impacts associated with a certain phase may be omitted from further consideration where no plans or projects have been identified that have the potential for cumulative effects during this period.

1.10.2.              Types of Cumulative Effect

Cumulative Visual Effects

  1. Cumulative visual effects consist of combined and sequential effects:
  • Combined visibility - occurs where the observer is able to see two or more developments from one viewpoint. Combined visibility may either be where several developments are within the observer’s main angle of view at the same time, or, where the observer has to turn to see the various developments. The cumulative visual effect of the Proposed Development may be significant, or not significant, depending on factors influencing the cumulative magnitude of change, such as the degree of integration and consistency of image with other developments in combined views; and its position relative to other developments and the landscape context in successive views.
  • Sequential visibility - occurs when the observer has to move to another viewpoint to see different developments. Sequential effects are assessed along regularly used routes such as major roads, railway lines and footpaths. The occurrence of sequential effects range from ‘frequently sequential’ (the features appear regularly and with short time lapses between, depending on speed of travel and distance between the viewpoints) to ‘occasionally sequential’ (long time lapses between appearances, because the observer is moving slowly and/or there are large distances between the viewpoints). The cumulative visual effect is more likely to be significant when frequently sequential.

Cumulative Seascape/ Landscape Effects

  1. Cumulative development within a particular area may build up to create different types of seascape/landscape effect. The significance of the cumulative seascape/ landscape effects of the addition of the Proposed Development will be assessed as follows.
  2. If the Proposed Development forms a separate isolated feature from other developments within the seascape/landscape, too infrequent and of insufficient significance to be perceived as a characteristic of the area, then the cumulative seascape/ landscape effect of the Proposed Development is unlikely to be significant.
  3. If the addition of the Proposed Development results in offshore windfarms and/or energy generation/ transmission developments forming a key characteristic of the seascape/landscape, exerting sufficient presence as to establish or increase the extent of a ‘seascape/landscape with windfarms’; then the cumulative seascape/ landscape effect of the proposal may be significant or not significant, depending on the sensitivity of the receptor and magnitude of the change.
  4. If the addition of the Proposed Development results in offshore windfarms forming the prevailing characteristic of the seascape/ landscape, seeming to define the seascape/ landscape as a ‘windfarm seascape/ landscape character type’ then the cumulative seascape/ landscape effect of the Proposed Development is likely to be significant.

1.10.3.              Assessing Cumulative Seascape, Landscape and Visual Effects

Cumulative Sensitivity of Landscape and Visual Receptors

  1. In evaluating cumulative sensitivity in the cumulative SLVIA (section 15.12 of Chapter 15), the sensitivity to change of seascape, landscape and visual receptors are retained from the main assessment in sections 15.10.

Cumulative Magnitude of Change

  1. The cumulative magnitude of change is an expression of the degree to which seascape, landscape and visual receptors will be changed by the addition of the Proposed Development cumulatively. The cumulative magnitude of change is assessed according to a number of criteria, described below. 
  • The location, position and visual relationship of the Proposed Development:  Depending on the viewpoint/viewing angle from the coast, the Proposed Development may be viewed adjacent to other developments on the skyline, covering a wider lateral spread; they may form one grouping or could be viewed separately on the skyline (separated by space on the skyline); or could be viewed with one project being ‘behind’ the other project. The overall magnitude of change will vary depending on this visual relationship at different viewpoints and is likely to be higher when two projects are viewed adjacent to each other over a wider lateral spread; and lower when one project is viewed behind the other project.
  • The location of the Proposed Development in relation to other developments:  If the Proposed Development is seen in a part of the view or setting to a landscape receptor that is not affected by other development, this will generally increase the cumulative magnitude of change as it will extend influence into an area that is currently unaffected by development. Conversely, if the Proposed Development is seen in the context of other developments, the cumulative magnitude of change may be lower as development is not being extended to otherwise undeveloped parts of the outlook or setting. This is particularly true where the scale and layout of the proposal is similar to that of the other developments as where there is a high level of integration and cohesion with an existing site the various developments may appear as a single site.
  • The extent of the developed skyline: the proportion (or horizontal angle) of the view that is affected by the combined lateral spread of the Proposed Development and other projects on the horizon. If the lateral spread/horizontal angle of the Proposed Development will add notably to the developed horizon in a view, the cumulative magnitude of change will tend to be higher.
  • The number and scale of developments seen simultaneously or sequentially: Generally, the greater the number of clearly separate developments that are visible, the higher the cumulative magnitude of change will be. The addition of the Proposed Development to a view or seascape/ landscape where a number of smaller developments are apparent will usually have a higher cumulative magnitude of change than one or two large developments as this can lead to the impression of a less co-ordinated or strategic approach.
  • The scale comparison between developments:  If the Proposed Development is of a similar scale to other visible developments, particularly those seen in closest proximity to it, the cumulative magnitude of change will generally be lower as it will have more integration with the other sites and will be less apparent as an addition to the cumulative situation.
  • The consistency of image of the proposal in relation to other developments:  The cumulative magnitude of change of the Proposed Developments is likely to be lower if its turbine height, arrangement, layout design and visual appearance/aesthetics are broadly similar to other developments in the seascape, as they are more likely to appear as relatively simple and logical components of the seascape.
  • The context in which the developments are seen: If projects are seen in a similar seascape/ landscape context, the cumulative magnitude of change is likely to be lower due to visual integration and cohesion between the sites. If projects are seen in a variety of different settings, this can lead to a perception that development is unplanned and uncoordinated, affecting a wide range of landscape character and blurring the distinction between them.
    1. The magnitude of change of the Proposed Development as assessed in the project alone assessment:  Where the Proposed Development is assessed to have a negligible or low magnitude of change on a view or seascape/landscape receptor, there is more likely to be a low cumulative effect.
    2. Definitions of cumulative magnitude of change are applied in order that the process of assessment is made clear. These are:
  • High - where the magnitude of change arising from the Proposed Development will result in a high cumulative change, loss or addition to the seascape/landscape receptor or view;
  • Medium - where the magnitude of change arising from the Proposed Development will result in a medium change, loss or addition to the seascape/landscape receptor or view;
  • Low - where the magnitude of change arising from the Proposed Development will result in a low change, loss or addition to the seascape/landscape receptor or view; and 
  • Negligible - where the magnitude of change arising from the Proposed Development will result in a negligible incremental change, loss or addition to the seascape/landscape receptor or view.
    1. There may also be intermediate levels of cumulative magnitude of change - medium-high and medium-low - where the change falls between two of the definitions.

Significance of Cumulative Effects

  1. The objective of the cumulative assessment is to determine whether any effects that the construction and operation of the offshore infrastructure will have on seascape, landscape and visual receptors, when seen or perceived cumulatively with the construction and operation of the other projects, will be significant or not significant.  Significant cumulative seascape, landscape and visual effects arise where the addition of the Proposed Development, leads to offshore windfarms becoming a prevailing seascape, landscape or visual characteristic of a receptor that is sensitive to such change. Cumulative seascape/ landscape effects may evolve as follows:
  2. A small scale, single development will often be perceived as a new or ‘one-off’ landscape feature or landmark within the seascape. Except at a local site level, it usually cannot change the overall existing seascape character, or become a new characteristic element of a landscape/seascape;
  3. With the addition of further development, it can become a characteristic element of the landscape/ seascape, as they appear as elements or components that are repeated. Providing there was sufficient ‘space’ or undeveloped landscape/seascape between each development, or the overlapping of several developments is not too dense; they would appear as a series of developments within the landscape/seascape and would not necessarily become the dominant or defining characteristic of the seascape nor have significant cumulative effects; and
  4. The next stage would be to consider larger scale developments and/or an increase in the number of developments within an area that either overlap or coalesce and/or ‘join-up’ along the skyline. The effect is to create a landscape/seascape where the offshore windfarm and/ or energy generation/ transmission element is a prevailing characteristic of the landscape/ seascape. The result would be to materially change the existing seascape/landscape character and resulting in a significant cumulative effect. A landscape/seascape characterised by offshore windfarm or energy generation/ transmission development may already exist as part of the baseline seascape context.
  5. Less extensive, but nevertheless significant cumulative seascape, landscape and visual effects may also arise as a result of the addition of the Proposed Development where it results in a seascape, landscape or view becoming defined by the presence of more than one offshore windfarm or similar/large scale development, so that other patterns and components are no longer definitive, or where the proposal contrasts with the scale or design of an existing or development.
  6. Higher levels of cumulative effect may arise when projects are clearly visible together in views, however provided that the projects are designed to achieve a high level of visual integration, with few notable visual differences between developments, these effects may not necessarily be significant. In particular, the effects of an extension to an existing development are often less likely to be significant, where the effect is concentrated, providing that the design of the developments are compatible and that the overall capacity of the seascape is not exceeded.
  7. The capacity of the seascape/ landscape or view may be assessed as being exceeded where the seascape, landscape and visual receptor becomes defined by a particular type of development, or if the Proposed Development extends across seascape/landscape character areas or clear visual/topographic thresholds in a view.
  8. More substantial cumulative effects may result from developments that have some geographical separation, but remain highly inter-visible, potentially resulting in extending effects into new areas, such as an increased presence of development on a skyline, or the creation of multiple, separate offshore windfarm defined seascape/landscapes.

1.11. Visual representations