The Future of Environmental Impact Assessments (EIA): Part 1

28.01.2025 6 min read

Part 1: History of EIA

The history of EIA has shaped the regulations and legislation to date, from international treaties to legal case law. Understanding its historical development reveals how EIA has adapted to address emerging challenges and further knowledge. In Part 1 we explore some important key milestones and their interactions with EIA.

EIA Evolution

In 1960, Rachel Carson, published “Silent Spring”, which played a hugely influential role in raising environmental awareness and building a public campaign against DDT (a chemical used as an insecticide). The increasing public concern and societal opinions regarding environmental issues were likely key factors in first laying the foundation for environmental laws and protection in the US.

By 1970, “Environmental Impact Assessments” became formalized in the United States with the introduction of NEPA One of the earliest applications was the Trans-Alaska Pipeline project, which required federal agencies to evaluate environmental effects systematically.

Unfortunately, another environmental health disaster in the US was shortly followed, and in 1978 the Love Canal Disaster ignited the environmental health movement in the US, globally highlighting the need for more stringent environmental protection laws.

The concept of EIA quickly gained traction and by 1985, the European Union introduced the EIA Directive (85/337/EEC), establishing minimum requirements for the process. In 1988, EIA became a formal requirement in the UK through the Town and Country Planning Regulations for England and Wales.

Multilateral Environmental Agreements (MEAs) and Trade Agreements

The 1992 Earth Summit (Rio Convention) was a pivotal moment in influencing improvements in EIA practice, specifically addressing the need to integrate environment and development in decision-making; encouraging governments to strengthen EIA frameworks and incorporate Strategic Environmental Assessments (SEA) as a new tool. Notably, Principles 17 and 19 of the Rio Declaration state:

Principle 17: “Environmental impact assessment, as a national instrument, shall be undertaken for proposed activities that are likely to have a significant adverse impact on the environment and are subject to a decision of a competent national authority.”

Principle 19: “States shall provide prior and timely notification and relevant information to potentially affected States on activities that may have a significant adverse transboundary environmental effect and shall consult with those States at an early stage and in good faith.”

In 1993, the UK signed the Convention on Environmental Impact Assessment in Transboundary Context (Espoo), which promoted environmental protection through EIA, and established the principle of transboundary EIA and cooperation. The convention also set a benchmark for best practices in EIA processes. The UK, as a signatory to the convention, has therefore certain obligations under international law.

Aarhus Convention

Five years later in 1998, the Aarhus Convention was adopted to provide a foundation for the principles of participative democracy and empower the role of society in environmental matters, with the UK ratifying this later in 2005. This international treaty played a key role in shaping EIA practice and the development of the SEA Directive; around its three pillars, through access to environmental information and reports, improving stakeholder engagement, and ensuring that the EIA is a formal procedure to be followed for compliance:

Environmental Consulting

Over time, updates to the EIA Directive and associated regulations have been implemented into UK law and associated case law has developed over decades to address MEAs, and emerging environmental challenges.

In May 2021, the UK and EU formally entered the Trade and Cooperation Agreement (TCA), The TCA governs post-Brexit environmental standards between the two parties, and as part of this encourages both parties to minimize technical regulatory divergence from international standards. Article 393 of the TCA states:

“The Parties reaffirm their respective commitments to procedures for evaluating the likely impact of a proposed activity on the environment, and where specified projects, plans and programmes are likely to have significant environmental, including health, effects, this includes an environmental impact assessment or a strategic environmental assessment, as appropriate.”

More recently in 2023, the UK also signed an agreement reaffirming its commitments to EIA: the Comprehensive and Progressive Agreement for Trans-Pacific Partnership or CPTPP. The partnership reaffirms commitments to MEAs of which the aforementioned declarations and conventions are part emphasising the need for high environmental standards and supporting international cooperation.

Green Financing

This is a good pause in our EIA timeline to recognise that rather than being a “cottage industry ”, EIA forms a key tool and an internationally accepted way of determining the impacts and significant effects of a development which has been embraced by most countries around the world and financial institutions as a way of deciding whether to invest in these schemes.

Since the start of the 20th century, financial institutions have progressed in addressing the environmental and social risks in project financing. Therefore going back to 2002, nine international banks convened to develop a banking industry framework for addressing environmental and social risks in project financing, with the launch of the Equator Principles (EPs) the following year..

The Equator Principles aim to provide a minimum standard for due diligence to support responsible decision making. In the most up-to-date EPs (2020), Principle 2 of this framework explicitly requires an appropriate environmental or social impact assessment to be undertaken. Therefore, it appears evident that the formation of these voluntary frameworks relies upon the integrity and robustness of EIA.

Indications of Reform in the Past 5 years

Despite all the strong historical backing of EIA and growing awareness of environmental and social risk, the past five years have seen significant political and regulatory shifts in the UK, including the impacts of Brexit  and the evolving attitudes and perceptions toward environmental regulation.

In 2020, the previous Government’s “Planning for the Future” White Paper consultation opened for opinions on changes to planning policy and regulations, focusing on digitalisation, maximising environmental benefits, and reducing duplication of efforts. The Institute of Environmental Management and Assessment’s (IEMA) formal response to this paper indicated that whilst there was agreement for the need for impact assessment reform that focussed on environmental outcomes, simplification must not reduce existing protections and consider EIA to be a proven tool to deliver the outcomes.

Two years later in 2022, the concept of full reform to the consenting regimes was again publicised, with the term Environmental Outcomes Reports (EOR) introduced within the Levelling Up and Regeneration Bill. Shortly after its royal assent, the previous government opened its consultation on this new approach to environmental assessment through EOR.

Despite a change in government, this idea of “EOR” seems to have retained momentum, and in December 2024, under the current government, further consultation opened on planning reforms. Despite no formal consultation response to the previous EOR consultation, the government has indicated that any new reform would be implemented under this new regime to replace EIA. It is not clear whether the current government therefore envisage the same “EOR” tool as their predecessors.

Further proposals on planning reforms are currently being published, which they propose to be included as part of the Planning and Infrastructure Bill later this year .

Next time in this series

We will discuss why there is a potential need for reform, and the challenges facing the EIA sector in the UK. We will begin to provide insight into what we currently understand about an alternative approach such as Environmental Outcome Reporting.

Key Contacts

Evie Scott Principal Consultant - EIA
Thomas Smeeton Senior Director - Environment
Temple