The evolution of environmental impact assessments

15th June 2023

Are we losing sight of its intended purpose and what does the future hold for EIA? Jo Beech, Tiziana Bartolini and Jessamy Funnell report.

Where did EIA begin?

Environmental Impact Assessment (EIA) was introduced in the 1980s through the EU directive 85/337/EC, however, the principle of environmental assessments was established earlier in the US. The original purpose of EIAs was to produce a high level of environmental protection by integrating environmental considerations into the development process. It was intended to apply to limited cases such as major infrastructure projects where there was potential for the greatest harm to the environment.

EIA also serves as an evidence base to support and justify planning decisions. EIA is an integral part of the UK planning system with the EIA planning practice guidance (EIA PPG) stating that its purpose is to ensure that a local authority has full knowledge of environmental effects and takes these into account during the decision making process. The EIA PPG reiterates that EIA should only apply to a small number of projects which are likely to have significant effects and that careful consideration should be given to whether a project is subject to EIA.

Evolution of EIA

EIA has significantly grown over time most recently to include effects on climate change, major accidents and disasters, and human health. It is often seen as a lengthy and technical process that is costly to the developer and in terms of the resources required within a local authority to determine such an application.

EIA is no longer applied only to significant infrastructure projects but to a variety of projects of varying scales. Some would argue that EIA has become too frequent in application as a result of a fear of legal challenge with objectors using it as a means to challenge a development.

The role of EIA post planning

There are several phases to the EIA process. Most people are familiar with the screening, scoping and preparation of an Environmental Statement (ES) or EIA Report, however, it is what happens after a project is granted consent that ensures whether EIA is successful in reducing environmental harm. ESs or EIA Reports provide the starting point by identifying impacts and mitigation measures necessary to avoid or reduce significant effects. It is the delivery mechanism and monitoring which dictates success.

Reserved matters applications for EIA developments should be supported by a review of the ES or EIA Report prepared at the outline stage and the identified mitigation requirements that ensure these are included in the detailed design. Planning conditions need to be suitably worded and enforced to ensure mitigation is implemented, with monitoring undertaken during construction and once schemes are operational. Live documents such as environmental management plans enable the continual application of best practice and mitigation to ensure no adverse harm results. These monitoring functions are the responsibility of local authorities and with increasing pressures on budgets and services it is questionable how this can be achieved.

What would happen if EIA did not exist?

Whilst EIA is engrained into the planning and development process, its absence would not result in ‘free rein’ and a significant harm to the environment. UK planning policy and legislation includes provisions covering topics such as climate change, flood risk, heritage and biodiversity. Regardless of whether EIA is required, these factors require consideration in designing a development and determining a planning application, but would be considered and reported on independently. Perhaps the real benefit of EIA is to create a uniform approach on how effects on the physical, social and human environment are considered and how effects these might interact.

The future of EIA?

The Levelling-up and Regeneration Bill, first published in May 2022, will replace the EU’s EIA and SEA systems with ‘Environmental Outcome Reports’ (EORs) and seeks to shorten planning consent procedures without reducing the level of environmental protection afforded under existing environmental law. The Bill shifts focus away from addressing environmental harm to securing ‘specified environmental outcomes’ which must be assessed against during relevant consents and plans. Without further details it is difficult to determine what the Bill means for EIA and, if it withstands the Bill, what EIA might look like in the future.

Jo Beech is senior town planner, Tiziana Bartolini is an environmental consultant and Jessamy Funnell is associate director at AECOM.


Please note: the views expressed in this blog are those of the individual contributing member and are not necessarily representative of the views of IEMA or any professional institutions with which IEMA is associated.


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