Environmental impact assessment

Purpose of EIA

An environmental impact assessment (EIA) is an assessment of a project's likely significant environmental effects. It enables significant effects on the environment to be given due weight, along with economic or social factors, when planning applications are being determined, and provides an opportunity for negative environmental effects to be reduced or mitigated where possible. It also gives the public and other consultees opportunities to participate in the decision-making procedures of consents which affect the environment. See Practice Note: Environmental impact assessments—key points.

Legislation and guidance

In a town and country planning context, the EIA process is governed by:

•
the Town and Country Planning (Environmental Impact Assessment) Regulations 2017, SI 2017/571 (the English EIA Regulations) in England, and
•
the Town and Country Planning (Environmental Impact Assessment) (Wales) Regulations 2017, SI 2017/567 (the Welsh EIA Regulations) in Wales

together the 'EIA Regulations'.

See Practice Note: Environmental impact assessments—key points.

The EIA Regulations transpose into English and Welsh law the changes made by Archived Directive 2014/52/EU to Archived Directive 2011/92/EU on the assessment of the effects of certain public and private projects

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