Environmental Impact Assessment (EIA) Services

An Environmental Impact Assessment (EIA) is a legally defined process used to identify, assess and manage the significant effects on the environment that may arise from a development proposal. Where a proposed development requires an EIA, the findings play a decisive role in the decision making process for planning permission.

Collington Winter Environmental provides specialist planning Environmental Impact Assessment services for developments across England and Wales. We support both public and private sector clients in navigating the Environmental Impact Assessment Regulations, ensuring projects comply with planning law while progressing efficiently through the planning system.

Understanding Environmental Impact Assessment (EIA)

An environmental impact assessment EIA considers how a development may influence a wide range of environmental factors, including:

• Ecology and biodiversity
• Population and human health
• Air quality and climate
• Water resources and drainage
• Landscape and visual effects
• Soil, geology and land use

The assessment identifies whether a development could result in significant environmental effects, either alone or in combination with other existing or proposed developments. Where impacts are identified, appropriate mitigation is proposed to avoid, reduce or offset any adverse effect.

EIAs are embedded within the town and country planning framework and form a critical evidence base for planners, statutory consultees and the appointed decision maker.

The Legal Framework: Environmental Impact Assessment Regulations

EIAs in England are governed by the Impact Assessment Regulations 2017, formally known as the Town and Country Planning (Environmental Impact Assessment) Regulations 2017.

These environmental impact assessment regulations determine:

• Which developments require an EIA
• How screening and scoping should be undertaken
• What information must be included in an Environmental Statement
• How environmental information must be considered during decision making

Compliance with the regulations is essential. Failure to follow the correct planning environmental impact assessment process can result in delays, refusals or legal challenge.

When Does a Proposed Development Require an EIA?

Whether a proposed development requires an EIA depends on its classification under Schedule 1 or Schedule 2 of the regulations and its likelihood of giving rise to significant effects on the environment.

Schedule 1 Development

Schedule 1 developments always require an EIA due to their scale or nature. These typically include:

• Nuclear power stations
• Large chemical and industrial installations
• Major waste disposal or hazardous facilities

Such developments are assumed to have potential for significant environmental effects and must be subject to full assessment.

Schedule 2 Development

Schedule 2 developments may or may not require an EIA. The need for assessment depends on:

• The size of the development
• Its location and environmental sensitivity
• The nature and scale of potential impacts

Residential schemes, infrastructure projects, energy developments and commercial uses often fall within Schedule 2 and require careful consideration under the country planning environmental impact framework.

Screening Opinions and Requests for Screening

Where there is uncertainty, developers can submit requests for a screening to the local planning authority. The authority will then issue a screening opinion, determining whether the proposal is likely to result in significant environmental effects.

A robust screening submission should:

• Describe the development clearly
• Identify relevant environmental factors
• Assess the likelihood of a significant effect
• Reference relevant thresholds and criteria

At Collington Winter Environmental, we prepare clear, evidence-led screening submissions that support proportionate decision making and help avoid unnecessary EIAs where impacts can be adequately controlled.

Scoping the EIA Process

If an EIA is required, the next step is scoping. Scoping identifies which topics must be addressed and the level of detail required within the Environmental Statement.

A scoping opinion issued by the local authority helps:

• Focus assessment on material environmental effects
• Avoid excessive or irrelevant reporting
• Provide clarity for consultees and stakeholders

Effective scoping is central to a streamlined EIA process and ensures assessments remain proportionate and policy-compliant.

Baseline Studies and Environmental Factors

Baseline data collection establishes the existing environmental conditions against which impacts are assessed. This includes surveys, desk studies and data analysis relevant to each environmental factor.

Accurate baseline information is essential for:

• Predicting potential impacts
• Assessing magnitude and significance
• Designing effective mitigation

Our ecology team undertakes detailed baseline assessments that provide a robust foundation for informed planning decisions.

Assessing Significant Environmental Effects

Impact assessment involves identifying how the development may affect environmental receptors during construction, operation and, where relevant, decommissioning.

Impacts are assessed in terms of:

• Nature and magnitude
• Duration and reversibility
• Sensitivity of the receiving environment

Where a significant environmental effect is identified, mitigation measures are proposed to reduce the impact to an acceptable level or remove it entirely.

Mitigation, Enhancement and Residual Effects

Mitigation measures may include:

• Design amendments
• Construction management controls
• Habitat creation or enhancement
• Long-term management strategies

The assessment also considers residual effects. These are impacts that remain after mitigation. Considering these effects ensures the decision maker has a clear understanding of environmental outcomes before granting consent.

Environmental Statements and Decision Making

The findings of the EIA are presented in an Environmental Statement (ES), which accompanies the planning application.

The ES forms a central part of the decision making process, enabling planning officers and committees to:

• Understand potential environmental impacts
• Consider representations from consultees and the public
• Make informed, legally compliant decisions

The decision maker must take the environmental information into account before determining the application.

Public Consultation and Transparency

EIAs promote transparency and engagement. Environmental Statements are made publicly available, allowing communities and stakeholders to comment on proposals that may affect their environment.

This consultative element supports balanced planning decisions and reflects best practice in town and country planning.

Public and Private Sector Experience

We deliver planning environmental impact assessment services for both public and private sector clients, including:

• Local authority-led projects
• Major residential and mixed-use developments
• Infrastructure and utilities
• Energy and industrial schemes

Our experience allows us to tailor assessments to the scale and complexity of each project while maintaining regulatory compliance.

International Considerations and the Espoo Convention

In rare cases where developments may have transboundary effects, the Espoo Convention applies. This international agreement ensures environmental impacts are assessed where a project in one country could affect another.

While most UK developments fall outside its scope, the Espoo Convention reinforces the importance of robust assessment and consultation principles within the UK EIA framework.

Why a Robust EIA Matters

A well-prepared EIA:

• Reduces planning risk
• Identifies issues early
• Supports sustainable development
• Strengthens the planning case

Conversely, inadequate assessment can lead to delays, refusals or judicial review.

How Collington Winter Environmental Can Assist

We provide comprehensive environmental impact assessment support throughout the planning lifecycle, including:

• Screening and screening opinion advice
• Scoping reports
• Ecological surveys and baseline studies
• Technical input to Environmental Statements
• Ongoing support during determination

Led by Ecology Director Olivia Collington, our team combines technical expertise with practical planning insight to deliver proportionate, defensible assessments.

Speak to Our EIA Specialists

If you need advice on whether your proposed development requires an EIA, or support navigating the Environmental Impact Assessment Regulations, our team is ready to help.

Early engagement can significantly reduce planning risk and streamline the assessment process.

Please contact us today for more information at info@collingtonwinter.co.uk or call the team on 01204 939 608.