Draft PPS18: Renewable Energy
Annex 1 Wind Energy Planning Issues: Nature Conservation
A39. Planning Policy Statement 2 Planning and Nature Conservation6 sets out the Department’s current planning policies on nature conservation that are taken into account when considering any development of land. As the development of a wind farm is a civil engineering project, there can be potentially serious implications for biodiversity. The major ecological impacts are most likely to be associated with site infrastructure rather than the turbines themselves – other than the impact of the moving blades upon birds and bats, and the advice contained in PPS 2 should cover all aspects of the development. With such extensive application sites there will very often be opportunities for developers to mitigate for any potential ecological damage and preferably enhance current wildlife habitats.
A40. Beyond designated sites and peatland habitats the impact of a wind farm on local nature conservation interests should be minimal. A typical wind farm will usually leave the land between the turbines totally unaffected. There is little evidence that domesticated or wild animals will be affected by a wind farm – indeed, there are examples of cows and sheep grazing right up to the base of turbines.
A41. Applications to harness wind energy may be made in Sites of International Nature Conservation Importance, and such applications will be subject to the most rigorous examination. Developers should also note that applications which have the potential to significantly effect any such site as a matter of policy will be subject to an Appropriate Assessment7
A42. Experience indicates that bird species and their habitats are rarely affected by wind turbine developments and the impact of an appropriately designed and located wind farm on the local bird life should, in many cases, be minimal. To date, the most common concern has been the risk of ‘bird strike’ i.e. birds flying through the area swept by the blades and being hit, causing injury or death. This is most likely to occur if a wind turbine is erected directly in a migration path, where there are high concentrations of particular species (i.e. birds feeding), or where there are vulnerable species. Most birds in flight can be expected to take action to avoid obstacles but different species will vary in their reaction and manoeuvrability. Most evidence to date suggests that the risk of collision is minimal. However, some areas are important for a variety of bird species protected under the EU and UK legislation (SPAs, SACs and ASSIs). These could represent potential constraints to wind farm development. As indicated in PPS 2 on nature conservation, the importance of complying with international and national conservation obligations must be recognised and wind farms should not adversely affect the integrity of designated sites. Protected species, such as hen harriers, occupy many areas outside designated sites and are protected across Northern Ireland. These factors have to be considered against the positioning and size of turbines, including the size of the area swept by the blades in relation to the air space used by the birds in the vicinity of the development.
A43. Early consultation between the developer and the Department’s Environment and Heritage Service (EHS) and RSPB is recommended. Most sites will require an assessment of breeding birds (between late March and early June) and wintering birds (November to February). Others, where potential ornithological sensitivities are higher, may require substantially more survey work, including studies of wintering/passage birds, raptors and moorland birds and detailed observations to quantify bird flight activity across the site.
A44. Among the other potential impacts to birds, loss of habitat, the deposition of spoil or hazardous substances from construction and operation, scrub and hedgerow removal should also be assessed.
“The risks of disturbance to bird species during construction and operation of the wind farm is also an important consideration. For some species this is of greater potential significance than collision mortality. Scottish Natural Heritage, in consultation with the British Wind Energy Association (BWEA), is preparing a ‘Methodology for assessing the effect of wind farms on ornithological interests’. Whilst this publication tackles the situation in Scotland it is equally relevant to England. In addition, the DTI’s Renewable Energy Programme has published a report ‘Cumulative effects of wind turbines’ in which Section 3 deals with ‘Cumulative effects on birds’. Both will be of use to developers when assessing the potential impact of proposed developments on bird life. Royal Society for the Protection of Birds (RSPB), World Wildlife Fund (WWF), English Nature and BWEA have also published ‘Wind Farm Development and Nature Conservation’. Another useful source of information is ‘Windfarms and Birds: An analysis of the effects of wind farms on birds, and guidance on environmental assessment criteria and site selection issues.”
RHW Langston & JD Pullan (2003). BirdLife International on behalf of the Berne Convention.
A45. The impact of the moving blades of a wind turbine upon bats and their ultrasound has also on occasion been raised as a concern, but there is little evidence to date to suggest that significant numbers of deaths or injuries will occur. Early consultation between the developer and EHS and the Bat Conservation Trust is recommended. Some sites may require the submission of a bat survey to assess the use of the site.
A46. In addition, under the EC Habitats Directive, other species or habitats of special interest may be present. For example, active peatland is of particular importance to the Region for its biodiversity, water and carbon storage and can be adversely affected by wind farm development. In general such areas should be avoided and where possible, encourage the restoration of degraded areas.
A47. The main potential impacts on habitats that can result in the reduction, or loss, of biodiversity are:
- Direct loss of habitat to the developments’ infrastructure, including turbine foundations, crane pads, buildings, roads, quarries and borrow pits;
- Degradation of habitats through alteration or disturbance, in particular arising from changes to hydrology that may alter the surface or groundwater flows and levels, and drainage patterns critical in peatlands and river headwaters and increase the risk of bog burst;
- Fragmentation of habitats and increased edge effects;
- Changes to land management brought about by improved access; and
- Degradation and loss of habitats outside the development site, especially wetland habitats that may arise from pollution, siltation and erosion originating from within the development site.
A48. Developers should ensure that their ecological advisers enter into early discussions with EHS about the presence and importance of species and habitats in and around a proposed development site. Discussions should assess any potential impacts and the scope for mitigation in the design and layout. A Phase1 Habitat Survey could usefully inform these discussions. In addition discussions with locally based groups such as the Ulster Wildlife Trust or RSPB could benefit the ecological assessment procedure.
6 This Planning Policy Statement is currently under review