An Environmental Impact Assessment is essential to ensure that development projects consider their potential environmental impact before starting work. This helps minimise the project's footprint on the surrounding area and protect sensitive ecosystems.

But, what does an Environmental Impact Assessment involve, when do you need one and how do they work?

This comprehensive guide will explore the key aspects of an Environmental Impact Assessment, including why it’s so important, who requires an EIA and how you can request one.

What Is an Environmental Impact Assessment (EIA)?

An Environmental Impact Assessment (EIA) is a comprehensive process that assesses the potential environmental consequences of a proposed development or project. It is a crucial tool for ensuring that development decisions are made with consideration for the environment, promoting sustainable practices and safeguarding the natural world.

EIAs, which are governed by the Town and Country Planning Regulations 2017, are conducted for a wide range of projects, from large infrastructure developments like motorways and power plants to smaller-scale projects like new housing developments or industrial facilities. 

The process involves evaluating potential impacts on various environmental aspects, including:

• Air quality: The impact of a project on air pollution levels, including emissions from vehicles, machinery or industrial processes.
• Water resources: The impact on water quality and quantity, including potential contamination from pollutants or changes in water usage.
• Land use: The impact on existing land use, habitats and biodiversity, including the potential for deforestation, habitat loss or disruption of wildlife.
• Noise pollution: The potential impact on noise levels, particularly in residential areas or sensitive environments.
• Visual impact: The visual impact of a project in relation to its surroundings, such as the construction of new buildings or infrastructure.
• Socioeconomic impact: The potential impact on local communities, including employment opportunities, housing needs and social cohesion.

Why Is an EIA Important?

An Environmental Impact Assessment aims to protect the environment by ensuring that local planning authorities consider all significant environmental impacts before deciding whether or not to grant planning permission for a project. The regulations set out a procedure for identifying projects which should be subject to an EIA, and for assessing the potential environmental impacts of a proposed project, including its effects on air quality, water resources, land use, biodiversity and human health. Ultimately, the goal is to promote sustainable development by integrating environmental considerations into the decision-making processes.

Who Requires an EIA?

In England and Wales, the Town and Country Planning Regulations 2017 specify which types of developments require an Environmental Impact Assessment. 

These include:

• Major infrastructure projects: Large-scale projects like motorways, power plants and airports are generally subject to EIA.
• Certain developments in sensitive areas: Projects located in areas with special environmental designations, such as national parks or areas of outstanding natural beauty, are also required to undergo an EIA.
• Developments with specific environmental impacts: Projects with significant potential to impact the environment, such as those involving hazardous substances or large-scale deforestation, require an EIA.

The EIA Process

Now let’s explore the standard process for conducting an Environmental Impact Assessment. Keep in mind, however, that the specific steps and requirements may vary depending on the location, size and complexity of the project, as well as local regulations and governing bodies.

Screening

The process begins with screening to determine whether a particular development requires a full Environmental Impact Assessment. The EIA regulations provide a set of thresholds and criteria for screening projects. For example, projects falling under Schedule 1 of the Building Regulations are automatically subjected to a comprehensive assessment, while those in Schedule 2 must undergo a screening process to determine their significance.

Scoping

If, after screening, it is determined that a project requires an Environmental Impact Assessment, the next step of the process is detailed scoping. Scoping is conducted to identify key environmental issues and concerns. This step also defines the boundaries of the assessment and helps in focusing on relevant factors, ensuring that the assessment is comprehensive and relevant.

Baseline Studies

Baseline studies are conducted to establish the existing environmental conditions of the project site. This involves assessing air and water quality, biodiversity, noise levels and other relevant parameters. These studies provide a basis for comparing the existing conditions with the potential impacts of the proposed development.

Environmental Impact Assessment

The Environmental Impact Assessment is conducted, including the collection and analysis of environmental data, the identification of potential direct, indirect and cumulative impacts, and the assessment and proposal of mitigation measures. This can include changes in project design, the implementation of technology or the recommendation of best practices to minimise environmental impacts.

Environmental Statement

The findings of the EIA, including the baseline studies, impact assessments and proposed mitigation measures, are compiled into an Environmental Statement. This document is submitted to the relevant authorities for consideration during the decision-making process.

Consultation and Public Participation

In the UK, the Environmental Impact Assessment process emphasises public participation and consultation. During this stage of the process, local communities have the opportunity to express any concerns and opinions, ensuring that a variety of perspectives are considered.

If any concerns are raised, developers will typically be required to respond to them in a detailed and constructive manner. This can include addressing concerns directly, modifying the project or proposing additional mitigation measures such as plans for monitoring pollution levels, protecting wildlife habitats or implementing community benefits programs.

Decision-Making

The last stage of the process is making and communicating the final decision. In other words, whether the proposed development meets all required environmental standards, and the project can go ahead. The Environmental Impact Assessment report and public comments are considered during the decision-making processes, including planning applications and permitting procedures. 

If the outcome is favourable, then the developer can begin construction in line with approved mitigation measures. However, if the EIA is not successful, then the project will need to be postponed and adapted so that it meets all Environmental Impact Assessment standards requirements.