Updated guidance on transboundary assessments

AECOM's Fay Lagan discusses the European Commission's new guidance on transboundary impact assessment and its potential impacts

The idea of transboundary assessments is well enshrined in environmental impact assessment (EIA) methodologies, but in the past six months there has been a further development.

The European Commission has published new guidance on transboundary EIA and, although not mandatory, it could change how EIA projects with transboundary effects are undertaken.

As island nations, the UK and Ireland have had less experience of truly transboundary projects in comparison with mainland Europe, although there are notable examples.

The development of a European electrical supergrid and, perhaps, the results of the forthcoming Scottish referendum may increase the numbers of transboundary EIA projects and so the new guidance will become more familiar to EIA practitioners.

Espoo Convention

The basic requirement of the EIA process is to assess any “likely significant effects” of a proposed development. This requires an assessment of effects regardless of the development’s location or of national borders.

The international community recognised the transboundary issue and agreed the Espoo Convention in 1991. It sets out the obligations of EU member states to assess the environmental effects of certain activities at an early stage of planning and to notify and consult other states.

For most projects involving transboundary effects, the environmental statement or environmental impact statement (ES or EIS) that is prepared as part of the national planning application process is considered to also serve the function of the Espoo Convention. This is the case as long as the cumulative effects are fully assessed and all parties are properly informed of the applications in the respective countries.

Cumulative assessments have long been guided by methodologies such as the commission’s Guidelines for the assessment of indirect and cumulative impacts as well as impact interactions (May 1999) and the Design manual for roads and bridges (assessment and management of environmental effects).

Updated transboundary guidance

In May 2013, the European Commission published Guidance on the application of EIA procedure for large-scale transboundary projects.

The aim of the document was to build on “experience and the good practices identified so far” in the EIA field and to provide clarification of how to approach “large-scale transboundary projects”.

An observation made of the Espoo Convention has been that it did not grasp truly transboundary projects (ie where the development crosses a border), but instead focused on a project within one state having an indirect or secondary impact on another.

The projects focused on and defined in the new guidance are those which are “physically located in more than one country”.

The commission describes seven key steps in a transboundary EIA:

  1. Notification and transmittal of information;
  2. Determination of the content and extent of the matters of the EIA information – scoping;
  3. Preparation of the EIA information/report by the developer;
  4. Public participation, dissemination of information and consultation;
  5. Consultation between concerned Parties;
  6. Examination of the information gathered and final decision; and,
  7. Dissemination of information on the final decision.

The guidance further states: “For large-scale transboundary projects, the developer must comply with the requirements of the national EIA requirements of each country in which the project will be implemented. The developer should prepare individual national EIA reports and a joint environmental report that covers the whole project and assesses its overall effects, in particular cumulative and significant adverse transboundary effects.” (Emphasis added)

In terms of the scope of EIA reports, the guidance states that the following should be included:

  • a description of the proposed project and its purpose;
  • a description, where appropriate, of reasonable alternatives (for example, in terms of location or technology to be employed) and the “no-action” alternative;
  • a description of the environment likely to be significantly affected by the proposed project and its alternatives;
  • a description of the potential environmental impact of the proposed project and its alternatives and an estimate of its significance;
  • a description of the mitigating measures considered and an indication of the predictive methods, assumptions and data on which they are based; and
  • an outline of monitoring and management programmes and any plans for post-project analysis.

The commission also advises that, when determining the EIA report’s scope and level of detail, it should be kept in mind that EIA has a “wide scope and broad purpose” and it should take into account the specific character and effects of each project.

Nord Steam project

The new guidance document makes specific reference to the Nord Stream project as a good example of a transboundary assessment.

Nord Stream is a 1,200km twin pipeline system that has been constructed along the Baltic Sea to transport natural gas from Russia to Western Europe. It was assessed as having the potential to affect nine countries. While separate planning applications were progressed in each country, an over-arching Espoo report was prepared.

This comprehensive document divided the EIA into study areas based on bio-geographic similarity, rather than territory and instead. For instance, one sub-region assessed an area along the territorial waters of Sweden, Finland, Latvia and Estonia.

This was a truly transboundary approach to the EIA and allowed the environment to dictate the study areas, rather than national frontiers. However, this was possible because of the large expanses of bio-geographic similarity in the marine environment. It is difficult to envision how this approach could be efficiently applied in the UK and Ireland because of the differing study areas between specialist assessments and the wide diversity of our landforms.

It is likely that the commission’s new guidance document will change the way EIA practitioners approach transboundary EIA. An additional report will be expected alongside the ES/EIS prepared in each member state. This additional joint environmental report will assess the project as a whole and be in addition to the cumulative impact assessment that would be included in the ES/EIS.

It is likely that the joint environmental report will be directly informed by the contents of the ES/EIS and so could serve as summary reports of the overall development. As this is a recent change to guidance, it is likely the area will evolve in the future with new transboundary projects as case studies.


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

Fay Lagan is an associate director (environment) at AECOM.

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