The visual and landscape impacts of wind farms are often the key focus for objections and are often the determining factor in whether or not consent is granted. The material used by landscape architects in assessing these impacts includes photomontages, wirelines, assessments of the zones of theoretical visibility (ZTVs) and other map based material. Professional judgment is then used to reach a conclusion regarding the impacts using all of these tools.
Over the last year there has been increasing debate regarding the way in which photomontages should be presented. There is no doubt that technological advances, in particular in relation to camera technology, offer opportunities to produce visualisations in a number of ways.
Scottish Natural Heritage's Position
SNH's "Visual Representation of Windfarms: Good Practice Guidance (February 2007)" sets out a range of methods that can be employed to produce these visualisations. This guidance recognises the limitations of visualisations and that no one method is necessarily any better than any other. In particular however, it does set out how a photograph taken with a fixed 50mm lens should be presented. For example it recommends that the vertical height of such an image should be at least 130mm but that 200mm is preferred and that the viewing distance must be correct – i.e. between 300-500mm, but ideally 400-500mm.
Single Frame Images
A debate regarding single frame images and their use was stimulated some time ago by "The Visual Issue: an Investigation into the Techniques and Methodology used in Windfarm Computer Visualisations – April 2007" by Architech Animation Studios (UK).
More recently, Perth & Kinross and Highland Councils have produced Draft Planning Standards and Requirements which seeks to require the production of single frame images in addition to panoramic photomontages. One of the requirements of these Planning Standards and Requirements is to produce images with different focal length lenses. Traditionally this would have involved significant additional work, in that individual viewpoints would have had to be photographed with different lenses or alternatively a variable focal length camera. The problem with the latter type of lens is ensuring that the precise focal length is actually achieved. There is a preference amongst landscape professionals for a fixed focal length camera to be used to avoid this problem. However, given the development and greater availability of 35mm format digital cameras with full frame sensors, it is now possible to use appropriate software to accurately recalibrate other focal lengths from an image taken with a fixed 50mm lens. Suitable equipment will therefore reduce the amount of work involved in having to comply with such requirements.
One question in relation to these requirements is whether it is in fact necessary for these additional visualisations to be part of the Environmental Statement (ES). ESs are already unwieldy documents and their purpose is to detail the assessments of the impacts of a development. The key concerns regarding the use of the material within an ES is that it is not considered to be "user friendly" by the general public. To this end, it may be that any additional visualisations, prepared primarily to aid the public's consideration of the project, should actually become part of the exhibitions relating to such projects and as supplementary information as opposed to being contained within the ES itself. This could provide a compromise between ensuring that the public can understand the information, whilst not creating an even more unwieldy document.
Scottish Ministers' Position
The Scottish Ministers have endorsed the guidance produced by SNH but have also recognised that in some circumstances single frame images may have a role to play. Indeed the Director and Chief Planner of the Scottish Government, Jim Mackinnon, wrote to the Heads of Planning on 20 January this year. In this letter he directs the Heads of Planning to the SNH guidance and in particular highlights that all images should be accompanied by a description of how to view the image, information as to whether it is a single frame image or a composite panoramic image and details of the horizontal field of view.
Given the increase in the number of windfarm developments coming forward, the quality of the visualisations has had to improve and in our experience it has. There is no doubt that some of the earlier material was quite poor. All visualisations have limitations and that different methodologies may be appropriate in different circumstances.
The position that any single form of image is to be preferred to any other has, however, not been borne out in our inquiry experience. On the contrary, we consider that there are a variety of practises and procedures which each has their own benefits and disadvantages. However, developing practise seems to suggest that single frame images are likely to be required as well as panoramic images. This mirrors developments in zones of theoretical visibility (ZTVs) which not only illustrate theoretical visibility but also the vertical and horizontal arc of view. Technology therefore continues to increase the tools in the landscape architect's toolbox.
If you would like further information on any of the matters raised in this update, please contact either Colin Innes on 0131 473 5104 or Pippa Bowyer on 0131 473 5493.