Somerset Landscape Sensitivity Assessment

This assessment draws on advice contained in Natural England’s ‘Approach to landscape sensitivity assessment’, which describes the term ‘landscape sensitivity’, within the context of spatial planning and land management, as follows:

“Landscape sensitivity may be regarded as a measure of the resilience, or robustness, of a landscape to withstand specified change arising from development types or land management practices, without undue negative effects on the landscape and visual baseline and their value.”

It is a term applied to landscape character and the associated visual resource, combining judgements of their susceptibility to the specific development type / development scenario or other change being considered, together with the value(s) related to that landscape and visual resource.

The study determines sensitivity of the landscape around settlements to two types of development as set out below in Table 2.2. These typologies represent generic forms of development most likely to come forward within the county. 

Landscape sensitivity assessment requires judgements on both landscape susceptibility and landscape value. Landscape susceptibility relates to how vulnerable the landscape is to change from the type of development being considered, in this case, built development. Landscape value relates to the consensus about importance, which can be recognised through designations as well as the ‘key sensitivities and valued features’ set out in the Somerset Landscape Character Assessment.

For assessment parcels situated on the border of the Somerset Council area, the Landscape Character Assessments for neighbouring authorities have been referred to where relevant. Where these assessments have not explicitly referred to key sensitivities and/ or valued features, the relevant key characteristics have instead been referred to in order to provide an indication of what makes the landscape sensitive to change.

The selection of landscape sensitivity indicators for the LSA were informed by attributes of landscape most likely to be affected by housing or commercial development. The sensitivity indicators include both ‘landscape’ and ‘visual’ aspects of sensitivity. The indicators include:

• Physical character (including landform, scale and field pattern)
• Natural character
• Historic character and time depth
• Character and setting of the settlement
• Visual prominence, skyline and views
• Perceptual and scenic qualities (including access and recreation)

The section below provides descriptors of each of the different indicators for landscape sensitivity and sets out some examples for each sensitivity score. As with the overall sensitivity score, these range from High to Low, with examples provided for high, moderate and low scores.

Physical character

This considers the shape and scale of the landform, landscape pattern and landscape elements in relation to the scale of potential development. Smooth, gently undulating or flat landforms are likely to be less sensitive to development than a landscape with a more dramatic landform, distinct landform features or incised valleys with prominent slopes.

This indicator considers how developments fit with the scale of the landform (understanding the scale of the development proposed is important when applying this indicator). Larger scale, simple landforms are likely to be less sensitive to larger scale developments than smaller scale, enclosed landforms (where large-scale developments could appear out of scale with the underlying landform). Conversely, smaller developments may be able to be screened within enclosed landforms, therefore reducing landscape sensitivity. Existing small-scale features in the landscape in the form of existing buildings or trees can also influence the scale of development that can be accommodated in the landscape.

Natural character

This indicator considers the ‘naturalistic’ qualities of the landscape in terms of coverage of semi-natural habitats and valued natural features (e.g. trees, hedgerows) which could be vulnerable to loss from development. Assessment parcels with frequent natural features (including large areas of nationally or internationally designated habitats) result in increased sensitivity to development, while landscapes with limited natural features (including intensively farmed areas or areas with high levels of existing development) will be less sensitive. Relevant natural heritage designations include Sites of Special Scientific Interest (SSSI), Ancient Woodland, Ramsar, Special Areas of Conservation (SAC), National Nature Reserves (NNR) Local Nature Reserves (LNR) and Local Wildlife Sites (LWS).

Historic character and time depth

This considers the extent to which the landscape has ‘time-depth’ (a sense of being an historic landscape, with reference to the Somerset and Exmoor Historic Landscape Characterisation and/or the presence of heritage assets that are important to landscape character (i.e. Conservation Areas, Registered Parks and Gardens, Scheduled Monuments, listed buildings, archaeological features and remains or other features listed in the landscape character assessment). Landscapes with small-scale, more irregular field patterns of historic origin are likely to be more sensitive to the introduction of modern development than landscapes with large, regular scale field patterns because of the risk of losing characteristic landscape patterns.

Character and setting of the settlement

This considers the overall settlement form and character of the existing settlement and considers whether development in the landscape would be in accordance with the general pattern, setting and form of current development and relationship with the existing settlement edge. It includes an understanding of the landscape pattern associated with settlement edges (where relevant), for example if it is well integrated by woodland cover or open and exposed to form a ‘hard edge’ to the adjoining landscape.

This indicator also considers the extent to which the landscape contributes to the identity and distinctiveness of settlements, by way of its character and/or scenic quality, for example by providing a backdrop/ setting, or playing an important part in views from a settlement. These considerations have greater weight when the settlement edge is historic or distinctive (for example if it forms part of a designated Conservation Area or its setting). This also considers the extent to which the area contributes to a perceived gap between settlements (the loss of which would increase coalescence).

Visual prominence, skyline and views

• This considers the visual prominence of the assessment parcel, reflecting the extent of openness or enclosure in the landscape (due to landform or land cover), and the degree of intervisibility with the surrounding landscape (i.e. the extent to which potential development would be visible).
• Visually prominent landscapes are likely to be more sensitive to development than those which are not so visually prominent. Landscapes which are visually prominent and intervisible with adjacent landscapes (both urban and rural) are likely to be more sensitive to development than those which are more hidden or less widely visible.
• It also considers the skyline character of the assessment parcel including whether it forms a visually distinctive skyline or an important undeveloped skyline. Prominent and distinctive and/or undeveloped skylines, or skylines with important landmark features, are likely to be more sensitive to development because new buildings/structures may detract from these skylines as features in the landscape. Important landmark features on the skyline might include historic features or monuments.

Perceptual and scenic qualities (including access and recreation)

This considers qualities such as the rural character of the landscape (traditional land uses with few modern human influences), scenic qualities, sense of remoteness, and the extent of public access via Public Rights of Way (PRoW) and/or Open Access Land.

Landscapes that are relatively remote or tranquil (due to freedom from human activity and disturbance and having a perceived naturalness or a traditional rural feel with few modern human influences) tend to increase levels of sensitivity to development compared to landscapes that contain signs of modern development. High scenic value also add to sensitivity in relation to this indicator. This is because development will introduce new and uncharacteristic features which may detract from scenic value or remoteness/naturalness.

Making judgements on levels of landscape sensitivity

For each assessment parcel, a commentary is provided against each sensitivity indicator and a score determined (as detailed above). This judgement relates to a generic sensitivity of each aspect of the landscape to the principle of generic built development. The commentary provided for each sensitivity indicator then informs the subsequent judgement on the overall landscape sensitivity of the assessment parcel to the specific development types (residential and commercial as described in Table 2.2). A five-point scale from ‘low’ to ‘high’ landscape sensitivity is used to define levels of landscape sensitivity for both of these judgements, as shown in Table 2.12.

The five defined levels of landscape sensitivity form stages on a continuum, rather than clearly separated categories. Any given landscape may or may not fit neatly into one category, and an element of professional judgement is required.

As with all assessments based upon data and information which is to a greater or lesser extent subjective, some caution is required in its interpretation. This is to avoid the suggestion that certain landscape features or qualities can automatically be associated with certain sensitivities – the reality is that an assessment of a landscape’s sensitivity to development is the result of a complex interplay of often unequally weighted variables (or ‘indicators’).

There may be one indicator that has a strong influence on landscape sensitivity in a particular assessment parcel which increases the overall landscape sensitivity score. In addition, it may be that a proportionally small area of the assessment parcel may raise the sensitivity of the entire assessment parcel. There may also be indicators that produce conflicting scores. For example, a small-scale landscape with historic field patterns may be considered as high sensitivity for ‘Historic character and time-depth’ but may also afford greater screening of development from topography and a dense network of hedgerows, and therefore score as low sensitivity for ‘Visual prominence, skyline and views’.

The judgement of overall landscape sensitivity is therefore based on transparent professional analysis, rather than a mechanical process of addition. All indicators are taken into account in the context of their importance to the landscape character and quality of the assessment parcel.

This study provides an assessment of the relative landscape sensitivities of the different assessment parcels to development, without knowing the exact location, layout, design or mitigation proposed. It therefore should not be interpreted as a definitive statement on the suitability of a certain location for a particular development. It is not a replacement for detailed studies for specific siting and design and all developments will need to be assessed on their individual merits.

It is also worth noting that the LSA considers the following:

• The natural character of the landscape but not specific ecological issues in relation to species or habitats;
• The historic and cultural character of the landscape but not specific cultural heritage/archaeological issues associated with individual designated heritage assets and their settings; and
• The visual character of the landscape but not visual amenity issues associated with specific receptors, such as the overall quality, experience and nature of public views from specific locations such as promoted viewpoints, or of private views and outlook available to occupants of residential properties.

These are all issues that will need to be taken into account in site selection and impacts will need to be reported at the time when individual proposals are put forward – as such they will be addressed through planning applications and Environmental Impact Assessment (EIA) process including more detailed landscape and visual impact assessments (LVIAs) or landscape and visual impact appraisals (LVAs).

This study concentrates on understanding the sensitivities to development and does not address capacity. Capacity is a further stage of assessment that requires consideration of cumulative development, landscape objectives, and thresholds of acceptable change to identify likely quantum of change that can be accommodated.

Finally, the study remains strategic and is based on the assessment of broad settlement edge assessment parcels. There may be spatial variations in character within any one assessment parcel and these are generally described in the text. Individual site level investigations will likely indicate further differences and variations at the site scale.

This study was undertaken at 1:25,000 scale and involved desk study and field work from roads, public rights of way and other public vantage points.