Environmental Impact Assessment

The Conference on the Human Environment, held in Stockholm in 1972 as part of the United Nations’ Environment Programme (UNEP), asserted the responsibility of States to ensure that activities within their jurisdiction or control do not cause damage to the environment of other States or of areas beyond the limits of national jurisdiction (principle 21 in the Declaration). In 1975, the Helsinki Final Act referred to “legal and administrative measures for the protection of the environment including procedures for establishing environmental impact assessments” and mandated the United Nations’ Economic Commission for Europe (UNECE) to follow up on the concept of EIA.

In September 1979 the Seminar on Environmental Impact Assessment took place in Villach, Austria under the stewardship of the UNECE. The reason for convening the meeting was that the rapid pace in technological and economic development led to detrimental effects on the environment and it was therefore recognised that policies needed to be formulated with the aim of averting future environmental damage while developing methods, procedures, techniques, and policies on Environmental Impact Assessment. The Seminar focused on the core elements of environmental assessments: the integration of environmental considerations into planning and decision-making, public information and participation, and EIA as an instrument for handling transboundary problems.

Even though there was no measure adopted in the field of environmental assessments under international law until 1991, the conclusions and recommendations of the Villach Seminar (presented in the conference summary) were essential drivers for the development of legislation on environmental assessments and in particular for the first EIA Directive in the EU.

By the early 1980s, EIA procedures were in place in a number of Member States and, in 1982, a Group of Experts on EIA was established under the Senior Advisers to ECE Governments on Environmental and Water Problems. In January 1987, the UNEP Group of Experts on Environmental Law elaborated the concept of EIA in a transboundary context.

As a result, the Espoo Convention on Environmental Impact Assessment in a Transboundary Context was adopted on 25 February 1991, followed by the Convention’s signature by the European Community (now European Union) and twenty-nine States in the period up to 2 September 1991. The Convention was opened for ratification, acceptance, approval and accession from 3 September 1991. The Convention entered into force ninety days after the sixteenth ratification (Poland, 12 June 1997) on 10 September 1997. The Convention, following its first amendment in 2001 (entry into force: 26 August 2014), is also open to accession by UN Member States that are not members of the UNECE.

In the 1992 Rio Declaration, the UN General Assembly also embraced and endorsed the precautionary principle by stating that “In order to protect the environment, the precautionary approach shall be widely applied by States according to their capabilities. Where there are threats of serious or irreversible damage, lack of full scientific certainty shall not be used as a reason for postponing cost-effective measures to prevent environmental degradation.”

In the sphere of public participation (one of the key elements of environmental assessments), the Aarhus Convention was adopted in 1998 and entered into force in 2001. Most importantly, it requires both public participation in decision-making and access to justice for projects which require the EIA.

With regard to strategic environmental assessment, the Kyiv Protocol was adopted at an extraordinary meeting of the Parties to the Espoo Convention on 21 May 2003 during the ‘Environment for Europe’ Ministerial Conference. Thirty-six States and the European Community (now EU) signed the Protocol, with Montenegro later succeeding to signature. The Protocol entered into force on 10 July 2010.

The International Court of Justice (ICJ) has played a significant role in affirming the customary law status of EIA. In its advisory opinion on the Legality of the Threat or Use of Nuclear Weapons, the ICJ indicated that EIA is a general obligation under international law. Subsequent cases, such as the Pulp Mills on the River Uruguay case, have further solidified this position.

The importance of EIA as customary law is multifaceted. Its universal application means that it binds all states, regardless of their participation in specific treaties, establishing a global baseline for environmental protection. It also provides a foundation for the development and implementation of international and regional agreements on EIA, strengthening the legal framework. Moreover, customary law sets a minimum standard for EIA processes, which states can then enhance through national legislation and agreements. Crucially, it provides a basis for holding states accountable for environmental damage resulting from a failure to conduct proper EIAs, establishing state responsibility under international law. Ultimately, EIA as customary law plays a vital role in promoting sustainable development by integrating environmental considerations into decision-making at all levels.