Environmental Impact Assessment (EIA)

Primary Source: Jöborn, I. (2006) Environmental Impact Assessment Swat Evaluation in Report on the SWOT analysis of concepts, methods, and models potentially supporting LCA. Eds. Schepelmann, Ritthoff & Santman (Wuppertal Institute for Climate and Energy) & Jeswani and Azapagic (University of Manchester), pp 83-87.

Level of analysis: Micro level. EIA is made for public and private projects, for example when planning for a new industry or infrastructure (roads, railroads, pipelines).

Assessed aspects of sustainability: Impacts on the environment and on human health, it can also include socio-economic or social impacts.

Main purpose of the assessment: To predict and communicate the impacts on the environment of projects in order to prevent negative environmental and assess socioeconomic impacts of the development. The outcomes of EIA are used to inform decision-making on whether to proceed with the development.

Description of the methodology: Environmental Impact Assessment (EIA) is a systematic procedure that examines the environmental consequences of development projects, at the proposal stage. It is a framework and can include several different methods and tools for analysis, depending on the technical/environmental content of the decision at hand. The analysis is prospective and site specific.

Detailed description

Environmental Impact Assessment (EIA) was first introduced in the USA in the National Environmental Policy Act (NEPA) in 1969. The aims were to evaluate environmental impacts of proposed developments, make the planning decisions more transparent and the process more democratic. NEPA has led to the adoption of similar environmental impact laws all over the world. The European Community Directive on EIA was introduced in 1985 (85/337/EEC) and was updated in 1997 (97/11/EC). The directive is applied to the assessment of the environmental effects of public and private projects that are likely to have significant effects on the environment.

EIA is a tool to assess impacts on the environment and on human health. In some countries, social or socio-economic aspects are also included. In other cases, the social impacts are analysed in a parallel process: social impact assessment (SIA). The aim of EIA is to prevent or minimise negative environmental impacts of a development action.


EIA is an instrument for supporting as well as documenting decision-making processes in planning. Important steps in the EIA process are (Glasson et al., 1999):

–          project screening,

–          scoping,

–          the consideration of alternatives,

–          the description of the project/development action,

–          the description of the environmental baseline,

–          the identification of the main impacts,

–          the prediciton of impacts,

–          the evaluation and assessment of significance,

–          mitigation,

–          public consultation and participation,

–          EIA presentation,

–          decision-making,

–          post-decision monitoring, and

–          auditing.

EIA is prospective (assessment of the future state of the environment, both with the project and in the absence of the project) and site specific (the different locations environmental values and problems are evaluated in order to decide the most suitable location for the development). One of the most important aspects of the EIA process is consideration of different alternative project locations, scales, processes, layouts and the “no-action” options. No-action is the state of the society and the environment in the future if the planned development is not carried out. The EIA tool is not intended to be used in order to get accurate answer about future environmental impacts, but to compare different alternative and evaluate which is the best for the environment, and to identify strategies to prevent or minimise negative environmental impacts.

The time-scale used in EIA depends on when the planned project will be finished and when the impacts are likely to appear. This can cover a period from one to several years (normally 10 to 15 years).

Participation and transparency are two key words in EIA. Likely environmental impacts of a proposal should be communicated throughout the whole process both internally in the project and externally with the concerned public and authorities. Examples of stages in the EIA process where consultation and participation can be useful (Glasson et al., 1999):

  • in determining the scope of an EIA,
  • in providing specialist knowledge about the site,
  • in evaluating the relaive significance of the likely impacts,
  • in proposing mitigation measures,
  • in ensuring that the EIA is objective, truthful and complete, and
  • in monitoring any conditions of the development agreement.

To be effective, the EIA process should start at the beginning of the planning process of the project. In this way environmental issues have the possibility to be integrated in the decision making process and negative impacts on the environment then can be prevented. Ideally the predicted impacts in the EIA should be audited and compared with those that actually occur once the development is finished. This stage is usually not carried out in practice.


Strengths with EIA are for example:

–          the procedure is relatively easy to implement and understand,

–          in Europe the EIA process and documentation are regulated in a EC directive,

–          environmental issues are integrated in the planing process of a project,

–          the procedure is relatively democratic, which is obtained through involving the public and other stakeholders in the planning process (fill in knowledge gaps, make the process more objective, and increase the chance for acceptance of the final decision),

–          this also makes the procedure transparent,

–          conflicts of interest become apparent early in the process,

–          site-specific environmental issues are integrated in the study,

–          alternative actions are searched for,

–          a no-action option is included in the assessment,

–          the prospective perspective makes it possible to consider future impacts in a society in change,

–          “soft” issues like landscape, archaeological and cultural assets, worries of potentially affected people etc. are qualitative described, and

–          cumulative effects and interactions between impacts are accounted for.


Weaknesses with EIA are for example:

–          uncertainty of results due to making predictions of a future development and inequality in the description of the environmental baseline (note, however, the aim of EIA is to compare the future environmental impacts between alternative actions, not to get accurate quantified predictions of the environmental impacts),

–          use of subjective elements in the evaluation,

–          feasible alternatives can be difficult to identify,

–          the time requirements and cost can be high,

–          the mix of qualitative and quantitative analyses makes it hard to compare the impacts of the alternative actions, and

–          there is rarely monitoring of actual impacts once the development has been finished to check whether the EIA predictions were correct or not.

Opportunities for broadening and deepening LCA

–          Conflicting interests often occur among stakeholders in a decision-making process. The public or authorities can, for example, have issues that they consider to be very important to analyse, but that are neglected in the LCA, because they are not considered important in a scientific context. This can cause conflicts later on in the process, for example when introducing a new product.

–          A decision often has impacts that can be quantified as well as impacts that are difficult or impossible to quantify.

–          Our society as well as the environment is in constant change over time. The complexity of this development is great because of the interactions between society and the environment. For example, future changes in the electricity system will affect the environmental impacts resulting from the use of electricity. Future changes in the environment, such as climate-change, in turn affect the sociotechnical systems.

–          These facts offer opportunities for the use of participative, qualitative and prospective elements from the participative EIA procedure in LCA or as a complementary procedure.

Threats for broadening and deepening LCA

Experience indicates that it is more likely to use LCA-thinking in EIA rather than the other way around. The risk of mixing EIA with LCA is that neither stringency nor proper accounting of the characteristics of decision making is made. Consequently the best way might be to keep the methods conceptually apart and understand their respective strengths and weaknesses, maintaining a conscious use of these widely different and complementing methodologies.

Literature/Internet links

Commission of the European Communities 1997. Council Directive 97/11 EC of 3 March 1997 amending Directive 85/337/EEC on the assessment of certain public and private projects on the environment. Official Journal. L73/5.

Glasson, J., Therivel, R. & Chadwich, A. 1999. Introduction to Environmental Impact Assessment, 2nd Edition. Spon Press, London.



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