Environmental impact assessment EIA

1 Overview
2 Updates
3 Related articles on Designing Buildings
4 External references

[edit] Overview

The purpose of an Environmental Impact Assessment (EIA) is to ensure that the environmental effects of a proposed development are properly considered. An EIA provides the local planning authority with better information about certain types of projects, enabling them to make a more informed decision about whether permission should be granted and to allow imposition of more appropriate conditions and obligations to mitigate possible negative impacts.

The Town and Country Planning (Environmental Impact Assessment) (England and Wales) Regulations 2011 sets out a requirement to carry out an EIA as part of the planning application process for certain projects (generally those which are large or environmentally complex).

For more information, see Environmental impact and also Environmental Outcomes Report EOR

Carrying out an EIA can involve a considerable amount of work, can cause significant delays and incur additional costs to a project. It may therefore be advisable to enter into early consultation with the local planning authority to determine whether an EIA will be required, and if so, what it should contain and what methodology should be used to carry out the necessary assessments.

If an applicant is uncertain about whether an EIA is required, they can ask the local planning authority for a decision called a 'screening opinion' (or screening decision). They can also ask the local planning authority for advice about the required scope of the EIA; this is called a 'scoping opinion' (or scoping decision). If the applicant disagrees with these opinions, they can appeal to the Secretary of State who will then make a direction.

EIAs are required for developments described in Schedule 1 and Schedule 2 of The Town and Country Planning (environmental impact assessment) (England and Wales) Regulations. This includes a wide variety of projects such as:

Power stations
Refineries
Certain industrial processes
Certain transport projects
Dams
Pipelines
Airports
Major projects (above certain thresholds set out in Schedule 2)
Developments in sensitive or vulnerable locations (thresholds do not apply in sensitive locations such as national parks or national nature reserves where every project must be screened for environmental impact assessment).
Unusually complex projects that may have adverse environmental effects.

An Environmental Statement (usually prepared by the developer) summarises the findings of the EIA process and is used primarily to inform decision makers regarding the environmental implications of the development. In addition, it should provide appropriate information for statutory consultees, other interested organisations and members of the public and should provide a basis for consultation.

An Environmental Statement may contain:

A description of the proposed development and its use.
An estimate of the likely residues and emissions resulting from the construction and operation of the development (water, air and soil pollution, noise, vibration, light, heat, radiation, etc.).
An assessment of how the development complies with planning policy.
An assessment of environmental opportunities and constraints.
An assessment of appropriate alternatives. This may include an assessment of possible alternative sites, so it is important that this is done during the very early stages of a project - not as a process of post-rationalisation after the client has already selected a site.
An assessment of the likely impacts of the development.

See Environmental Statement for more information.

[edit] Updates

In April 2015, the Town and Country Planning (Environmental Impact Assessments)(Amendment) Regulations 2015 came into effect, raising the threshold above which a screening decision is required to determine whether an environmental statement is necessary, as set out in the Town and Country Planning (Environmental Impact Assessment) Regulations 2011. Controversially, this raised the threshold for industrial estates, residential developments and other urban developments from 0.5ha to five ha (or 150 units for residential developments).

In addition, in April 2014, the Council of the European Union approved changes to the environmental impact assessment directive with new elements including '...a mandatory assessment of reasonable alternatives studied by the developer, broader scope, as the EIA will cover new issues, and more detailed provisions on screening'. Member states have three years to incorporate the changes into national legislation (ref. EN, Council approves environmental impact assessment directive 14 April 2014).

In December 2016, the UK government launched a consultation on proposed changes to legislation that are needed to implement amendments introduced by the 2014 Directive. The consultation closed in January 2017.

In October 2018, the government published statutory instruments confirming that developers will still be required to undertake EIAs after the UK leaves the European Union, ensuring continuity of planning policy.

However the idea of uisng an alternative to Environmental Impact Assessments (EIA) was discussed, proposals bringing forward a new domestic framework for all the environmental assessment regimes which originated from the EU Environmental Impact Assessment Directive (EIA) and Environmental Assessment of Plans and Programmes (Strategic Environmental Assessment or SEA) Directive slowly started to appear.

In 2022 proposals by the Sunak Conservative Government were presented and a consultation 'Environmental Outcomes Report: a new approach to environmental assessment' which was published 17 March and closed 9 June 2023. The aim of the new approach being to be more effective as a tool for managing the effects of development on the natural environment, supporting better, faster and greener delivery of infrastructure and development, by simplifying and streamlining the assessment process making a more effective tool to support the delivery of environmental commitments. These proposals included the use of the Environmental Outcomes Report (EOR) as a replacement to Environmental Impact Assessments (EIA).

In 2024 under the Labour Government a number of propsals looked primarily at reform of the planning system to support development and economic growth, which included streamlinig processes, an outcomes-focused approach to impact assessments and the introduction of Environmental Outcomes Report (EOR) to replace Environmental Impact Assessments (EIA). In December 2024 the Policy paper "Planning Reform Working Paper: Development and Nature Recovery" concluded the approach proposed "shifting to a strategic and more outcomes-focused approach to impact assessment and nature recovery has great potential to support the environment as well as helping us deliver the housing and infrastructure we need. This shift to focussing on outcomes aligns with the ongoing work to implement Environmental Outcomes Reports."

By January 2025 the Chancellor announced 'Government goes further and faster on planning reform in bid for growth' outlining a number of further changes following those to the NPPF, looking towards infrastructure, reiterating the role of EORs and the environment saying:

"The government is also reforming environmental impact assessments, which have strayed from their original purpose of supporting decision making and have become voluminous and costly documents that too often support legal challenges rather than the environment. They will be replaced by Environmental Outcome Reports which will be simpler and much clearer, which will support growth by saving developers time and money, whilst still protecting the environment. The government will publish a roadmap for the delivery of these new Environment Outcomes Reports in the coming months."