Retrospection and alternative sites

Experts from WSP ask whether a retrospective approach to the consideration of alternative sites is the best that environmental impact assessment (EIA) practitioners can hope for?

The EIA Directive requires projects subject to EIA, to present an “outline of the main alternatives studied by the applicant or appellant and an indication of the main reasons for the choice made, taking into account the environmental effects” to be reported in the environmental statement (ES) and non-technical summary.

While the Directive only requires the presentation of an outline discussion of alternatives the developer has considered, good practice encourages the discussion of a number of scenarios, which include the consideration of alternative sites.

The quality of the consideration of alternative sites within an ES largely depends on the availability of relevant environmental information and the stage at which environment practitioners were engaged in the development process. If practitioners are engaged at early stage, during the allocation of the site within the local development plan, for example, they are be able to influence the spatial location and an appropriate level of data can be appropriate logged and stored for future use within an ES.

However, if practitioners are engaged at a later stage, such as the preparation of the planning application, they may find that environmental factors have played no or only a limited role in the site selection process. It may well be that other economic or commercial criteria have outweighed environmental factors. In this scenario there may be a need to undertake retrospective analysis to provide some consideration of alternative sites in line with the EIA Directive.

In this situation, WSP are now using a high-level environmental appraisal tool to prepare the retrospective analysis. This tool identifies alternative sites (if they are not known) and facilitates an independent review of those sites based on clear environmental criteria. If this approach is to be adopted, it is important to identify the sites, scope, methodology and associated limitations of the analysis at the EIA scoping stage. This ensures transparency of the approach to be adopted and considered by the determining authority and their consultees.

The key stages of this tool are:

  • Identification of alternative sites. There is a range of sources where information on potential alternative sites can be identified and these vary depending on the nature of the development. For example, for a major mixed-use scheme, alternative sites can be identified through a review of the local planning authority’s strategic housing land availability assessment.
  • Collection of publically available information from databases or in-house geographic information software tools.
  • Establishment of clear criteria against which to evaluate the alternative sites.
  • Scoring the sites using the criteria.
  • Ranking the sites in order of environmental suitability or preference.

The scores attributed across the technical disciplines for each alternative site can then enable conclusions to be drawn, although there may be a need for supplementary evaluation. Where there is insufficient environmental data to determine a score against the criteria, a middle ranking score can be assigned to ensure a fair assessment and to provide the best comparable score.

The EIA Directive suggests the consideration of alternatives should be undertaken at an early stage in the development process, allowing the evaluation of environmental factors and influencing the spatial location of the development.

As the development process advances, the opportunities to influence the alternative sites considered become increasing limited. It is in this scenario, that practitioners may need to undertake retrospective consideration of alternatives. However, as the analysis is independent, it may not always support the location in which the developer is seeking planning consent for and may compromise the purpose of the consideration of alternatives as intended by the EIA Directive.

Where a site is allocated for development within a development plan, there is likely to be a greater level of environmental analysis which may have contributed to the location of the development. If environment practitioners are engaged early in the process, they can influence and assist with the logging of documentation and decisions for future use within an ES.

If the site has not been allocated, there has been little consideration of environmental factors during the allocation process and/or the practitioner is only involved during the latter stage of the project, is retrospective analysis maybe the best we can hope for? If so, that raises other questions as to the effectiveness of the EIA Directive in enabling a robust consideration of alternatives, particularly when you bear in mind that the Directive is focused on the project level assessment, and whether closer scrutiny be applied to the strategic assessments at the plan level. Also, if a site has not been allocated and is proceeding towards a planning application, should spatial alternatives even be considered?


This article was written as a contribution to the EIA Quality Mark’s commitment to improving EIA practice.

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