Assessment of the visual and historic environment effects of operational wind farms in Northumberland

EXECUTIVE SUMMARY FINDINGS

The following points set out the key findings of this study. These should be viewed as headline points only, and full context for these findings is presented in the following chapters and appendices.

Overview of Landscape, Visual and Heritage Effects

• Significant adverse landscape and visual effects from wind energy developments have arisen in parts of Northumberland. However, these are in the main localised in extent although some longer distance impacts were observed. 

• Significant cumulative landscape and visual effects across those parts of the county studied are also localised in extent (for example Wandylaw with Middlemoor and Boundary Lane with Kiln Pit Hill Wind Farms). 

• Most installed wind energy developments across the county (at the time of study) have altered the balance of features within the landscape locally, but generally have not altered that character either significantly or irreversibly. 

• The potential for harmful adverse cumulative landscape and visual and character effects is however increasing, and in more sensitive locations, significant.

• Landscape capacity may be close to its thresholds in parts of the county. 

• Adverse effects upon important views and vistas from some of Northumberland’s most distinctive and important landscape and heritage  features have been identified. In particular, inland vistas from the Northumberland Coast Area of Outstanding Natural Beauty (AONB), and particularly from some of its outstanding heritage assets (in particular the coastal Castles) have been eroded as has its wider landscape context and sense of remoteness.

• The passage of time was found to have significant effects in relation to the visual prominence of wind turbines, both negative and positive due to forest clearance and more generally woodland and vegetation growth. 

• Effects on the setting of specific heritage assets have generally been limited and have not significantly degraded the value of this distinctive resource across Northumberland overall. However, views from and the immediate context of some specific sites have been harmed. 

Technical Findings

• Submitted landscape, visual and heritage assessment material in support of planning applications for wind energy developments varies in quality and accuracy, but was mostly found to present conclusions with which this study concurred although specific points of disagreement have arisen (for example, in the scale of zones within which likely potential adverse effects might arise).  

• Photomontages, (notwithstanding issues of accuracy) were helpful in assessing landscape effects to a greater degree than wireframe visualisations. Within the general support for the conclusions of ES material on landscape and visual effects, issues of inaccuracy in visualisations were consistently observed as listed below.

• Photomontages and wireframes are usually presented at A3 size within a separate volume of the ES or as part of the main ES, and either way are often large unwieldy documents that proved very difficult to use in the field. 

• Photomontage and wireframe visualisations of proposed wind energy developments invariably present images which when observed in the field under-represented the scale of visual prominence of installed turbines by around 30%.

• Some wind farm layouts as installed diverge from visualisations by a magnitude greater than could be attributed to micro-siting variations. 

• Selection of visualisation viewpoints were found on occasion to be unhelpful by using sites where vistas of the proposed development was limited or screened, yet open vistas could be found in close proximity.

• Supporting material to help accurately locate visualisation viewpoints (grid references, descriptions and OS mapping extracts) was frequently inaccurate or not-fit-for purpose.

• Determination of the ‘significance’ of predicted impacts was inconsistently arrived at across the study sample.

• Where systematic matrices were presented for determining the ‘significance’ of effects as a function of magnitude of effect and sensitivity of the receptor, professional judgements would tend to underplay effects where marginal assessments arose, although examples of a precautionary judgement were also observed.

• Significance matrices tended to weight possible outcomes towards nonsignificant effects.

• Significance matrices differed in respect to the transparency of categorisation of effects or magnitude of change.

• There tended to be an inverse correlation between the age of the ES or other supporting material and their quality and transparency, although the technical shortcomings noted above were evident over more recent outputs as well as older materials.