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These Guidelines have been developed by the Institute of Ecology and Environmental Management (IEEM) to promote good practice in Ecological Impact Assessment (EcIA) relating to marine, coastal and estuarine environments of Britain and Ireland. They complement and in part overlap the Guidelines for EcIA for the UK1, which cover all terrestrial, freshwater and coastal environments to extreme high water.

EcIA is a key sub-component of statutory Environmental Impact Assessments (EIA) and is therefore subject to the relevant EIA Regulations where undertaken as an integral part of an EIA. However, unlike EIA, EcIA is not currently in itself a statutory requirement. It is an evaluation process undertaken to support a range of environmental assessments and/or appraisals. ‘If properly implemented it provides a scientifically defensible approach to ecosystem management’ (Treweek, 1999)2.

EIA and EcIA should be undertaken by qualified professionals with experience in ecological survey and impact assessment and recognised by a relevant professional body e.g. IEEM.

EcIA should include the following stages:

  • scoping, involving consultation to ensure the most effective input to the definition of the scope of an EcIA (in practice, scoping is iterative throughout the EcIA process);
  • identification of the likely zone of influence, which may vary during the whole lifespan of the project;
  • identification and evaluation of ecological features, resources and functions likely to be affected by the project;
  • identification of the drivers of biophysical changes attributable to the project;
  • identification of the biophysical changes attributable to the project that are likely to affect valued ecological features and resources;
  • assessment of whether these biophysical changes are likely to give rise to a significant ecological impact, defined as an impact on the integrity of a defined site or ecosystem and/or the conservation status of habitats or species within a given geographical area, including cumulative and in-combination impacts;
  • refinement of the project to avoid or reduce identified negative impacts and incorporate mitigation measures and/or compensation measures for any residual significant negative impacts and ecological enhancement measures to improve the wider environment;
  • assessment of the ecological impacts of the refined project and definition of the significance of these impacts, including cumulative and in-combination impacts;
  • provision of advice on the consequences for decision making of the significant ecological impacts, based on the value of the resource, feature or function; and
  • provision for monitoring and following up the implementation and success of mitigation and compensation measures and ecological outcomes, including feedback in relation to predicted outcomes.

The EcIA process should be iterative and responsive to increasing knowledge as the project evolves. It is also a ‘partnership’ process, which is most effective if all contributing ecologists and other specialists work in collaboration. An EcIA should clearly and simply describe the impacts of any project so that all interested parties understand the possible implications of what is proposed. It should improve and allow for informed decision-making.

Experience has shown that the process of EcIA can be greatly improved by early consultation with the statutory nature conservation organisations (SNCOs), Environment(al) Protection Agencies (EPA) and the voluntary sector (NGOs). In the first instance problems can be resolved by making sure that the client organisation (developer/proponent) is fully aware of relevant site designations and their implications before pursuing their project. Once a commitment has been made to pursue a project, engagement with the SNCOs, EPAs and NGOs on a regular basis is recommended, especially at the screening and scoping stages, but also (especially in the case of possibly contentious cases) during the development of EcIA. This is an essential pre-requisite for minimising misunderstanding and controversy. It can also provide an effective environment for problem-solving in the case of major projects that have important impacts but accord with Government policy statements on essential infrastructure.