Environmental impact assessments in the UK — practice note

LexisNexis Legal & Professional, LexisNexis UK, LexisPSL, Environment, 11 July 2017


An EIA is an assessment of a project's likely significant environmental effects. It enables environmental factors to be given due weight, along with economic or social factors, when planning applications are being considered, as well as the scope for reducing them.


R (Goodman) v Lewisham London Borough Council [2003] All ER (D) 202 (Feb)

R (Wye Valley Action Association) v Herefordshire Council (National Farmers Union intervening) [2011] All ER (D) 188 (Jan)

It also gives the public and other consultees opportunities to participate in the decision making procedures.

Legislation and guidance

From 16 May 2017 onwards, EIA in respect of town and country planning matters 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.

The EIA Regulations transpose into English and Welsh law the changes made by EU Directive 2014/52/EC to EU Directive 2011/92/EU on the assessment of the effects of certain public and private projects on the environment, in so far as they govern town and country planning matters. See Practice Note: Directive 2014/52/EU on environmental impact assessment and New Environmental Impact Assessment Regulations made for more background.

Where a request for a scoping opinion was made, or an environmental statement submitted, before 16 May 2017, projects will continue to be governed by:


SI 2017/571, reg 76

SI 2017/567, reg 65

  • The Town and Country Planning (Environmental Impact Assessment) Regulations 2011, SI 2011/1824 (the 2011 EIA Regulations) in England, and
  • The Town and Country Planning (Environmental Impact Assessment) (Wales) Regulations 2016, SI 2016/58 (the 2016 EIA Regulations) in Wales together the Old EIA Regulations. The Old EIA Regulations will also continue to apply to screening opinions and directions in respect of which a request has been made before 16 May 2017 (or where the making or adoption of such opinions or directions was initiated before 16 May 2017).

Planning Practice Guidance provides guidance on the EIA procedure.


Planning Practice Guidance - EIA

When EIA is required

Schedule 1 and schedule 2 projects

In both England and Wales, an EIA is required for:

  • projects listed in Schedule 1 of the English and Welsh EIA Regulations, for which EIA is required in every case, and
  • projects listed in Schedule 2 of the English and Welsh EIA Regulations, for which EIA is required only if the particular project in question is judged likely to give rise to significant environmental effects—see Practice Note: Environmental impact assessment: meaning of ‘significant effect’

A project which falls into either of these categories is known as ‘EIA development’.

Whether an EIA falls into Schedule 2 may depend on:

  • the sensitivity of the area
  • mitigation measures
  • cumulative effects—in Ecologistas en Accion-CODA v Ayuntamiento de Madrid, the court established that, what is in substance and reality a single project, cannot be 'salami-sliced' into a series of smaller projects, each falling below the threshold criteria that EIA scrutiny is required.

See Practice Note: Environmental impact assessment—screening and scoping, which gives more detail on the factors that local planning authorities (LPAs) consider when deciding whether development is EIA development.

Where a consent procedure involves more than one stage (a ‘multi-stage consent’), the likely significant effects of a project on the environment should be identified and assessed at the time of the procedure relating to the principal decision. If effects are not identifiable at that time, the EIA must be undertaken at the subsequent stage. See Practice Note: Environmental impact assessment—screening and scoping.

The definitions in Schedule 2 are inherently imprecise. There is legitimate scope for differences of approach between different authorities. The courts role is supervisory, to check that the decision as to whether development falls within Schedule 2 was taken lawfully. It must not take on the function of primary decision maker and will only intervene if an LPA's decision is irrational.

It does not follow that a project must constitute 'development' under Town and Country Planning Act 1990, s 55 (TCPA 1990) in order to fall within the EIA Regulations. For example, demolition is capable of falling within the EIA Regulations, despite its exclusion from 'development' under s 55(2)(g).


Save Britain's Heritage v Secretary of State for Communities and Local Government, [2011] All ER (D) 305 (Mar)

Town and Country Planning Act 1990, s 55

LPAs should interpret ‘development’ broadly so as to include, wherever possible, projects which require EIA under the EIA Regulations.


Save Woolley Valley Action Group v Bath and North East Somerset Council, [2012] All ER (D) 25 (Aug)

If the project has several stages, the likely significant effects of a project on the environment should be identified and assessed at the time of the procedure relating to the principal decision. See Practice Note: Environmental impact assessment—screening and scoping.

In Thornhill v Cambridge City Council, the Court of Appeal held that a change of use of a second hand car sales site to a car hire business with ancillary office space on a scrap metal yard did not qualify as a change to or an extension of an 'industrial estate development project', as the scrap metal yard could not be so described in accordance with the first column of para 10(a) of the table in Sch 2 to the 2011 Regulations. Paragraph 10(a) in column 1 had to be construed in the context of the descriptions of the other infrastructure projects which fell within para 10, and not in isolation from the applicable thresholds in column 2. When para 10 was read as a whole together with the two columns, they gave a clear indication of the nature and size of those infrastructure projects that might be likely to have significant effects on the environment for the purposes of the English EIA Regulations.


Thornhill v Cambridge City Council [2015] EWCA Civ 340

Voluntary EIA

In certain circumstances, developers might increase their project’s certainties of cost, timescale and outcome by voluntarily submitting an environmental statement even where the EIA Regulations do not require it.

The EIA Regulations provide the Secretary of State/Welsh Ministers with residual discretion to direct that any Sch 2 development still needs an environmental statement, even if even if it is not in a 'sensitive area' or does not meet the thresholds or criteria in Sch 2. It is open to an LPA or an objector to request such a direction. See Practice Note: Environmental impact assessment—screening and scoping.


Town and Country Planning (Environmental Impact Assessment) Regulations 2011, SI 2011/1824, reg 4(9)

Town and Country Planning (Environmental Impact Assessment) (Wales) Regulations 2016, SI 2016/58, reg 4(9)

The Town and Country Planning (Environmental Impact Assessment) Regulations 2017, SI 2017/571, reg 5(7)

The Town and Country Planning (Environmental Impact Assessment) (Wales) Regulations 2017 SI 2017/567, reg 5(12)

A developer might consider a direction by the Secretary of State/Welsh Ministers possible where eg:

  • the size of the site is close to the threshold and could potentially exceed the threshold through a different means of calculation
  • strict application of the EIA Regulations does not necessitate an environmental statement but, objectively, that result would be considered unusual in the context

If there is a possibility of such a direction, it may be worth considering voluntary submission of an environmental statement, so as to avoid uncertainty and later delays. Developers often have to prepare reports and assessments on relevant environmental matters for the LPA even where no EIA is required, because such matters are likely to be material planning considerations, irrespective of the EIA Regulations.

The disadvantages of preparing an environmental statement where it is not legally required are:

  • additional publicity requirements
  • delay, due to time in carrying out the EIA, drafting the statement and a longer determination deadline (16 weeks). This could also interfere with using permitted development rights, where relevant
  • additional costs of employing environmental consultants and additional legal assistance to prepare the environmental statement

Once a developer has opted in to voluntarily produce an environmental statement, the EIA Regulations apply in the same way as if the environmental statement had actually been required by a screening opinion or direction.

Development covered by the regulations

The EIA Regulations apply to:


Planning Practice Guidance: Development covered by the regulations - list of relevant development consent mechanisms and controls

Planning conditions can indicate need for EIA

In Champion v North Norfolk District Council the LPA decided that no EIA was necessary, despite the proximity of the development site to a Site of Special Scientific Interest (SSSI) and a special area of conservation (SAC). However, it imposed conditions relating to the monitoring and, if necessary, restoration of water quality so as to avoid harm to the SSSI and the SAC. The High Court quashed the decision to grant consent, on the basis that it was irrational and inconsistent with the screening decision. The Court of Appeal overturned the High Court's decision. It held that the screening process and the consideration of the application at committee were separate processes and nothing in the committee papers suggested that the condition was imposed because it was considered that there was a likelihood of diminution of water quality.


Champion v North Norfolk District Council [2015] All ER (D) 233 (Jul)

The Supreme Court upheld the Court of Appeal's decision. It noted that cases of material doubt should usually be resolved in favour of EIA and the failure to treat the present proposal as EIA development was a procedural irregularity. Despite this, the Supreme Court noted that although there was a legal defect in the procedure, it has discretion to refuse relief if the applicant has been able, in practice, to benefit from the rights conferred by European legislation and if there is no substantial prejudice. It was not evident that the LPA’s decision would have been different if the procedure had followed the EIA regulations, and concerns about adequate hydrological separation were being addressed.

Wherever there is a risk of the development having a significant effect on the environment, the LPA must require an EIA. It cannot simply impose planning conditions to deal with the risk.

Pre-commencement conditions

Regulation 3 of the EIA Regulations prohibits both the grant of planning permission and any ‘subsequent consent’ in relation to EIA development unless environmental information has been considered.


The Town and Country Planning (Environmental Impact Assessment) Regulations 2011, SI 2011/1824, reg 3

The Town and Country Planning (Environmental Impact Assessment) (Wales) Regulations 2016, SI 2016/58, reg 3

The Town and Country Planning (Environmental Impact Assessment) Regulations 2017, SI 2017/571, reg 3

The Town and Country Planning (Environmental Impact Assessment) (Wales) Regulations 2017 SI 2017/567, reg 3

A ‘subsequent application’ means an application for approval of a matter where the approval:

  • is required by or under a condition to which a planning permission is subject, or
  • must be obtained before all or part of the development permitted by the planning permission may be begun (ie includes the discharge of pre-commencement conditions, which must be complied with before the development can be commenced) See Practice Note: Implementing planning permission

If an LPA fails to take the environmental consideration into account when discharging a pre-commencement condition, the discharge will be unlawful. The ‘Whitley principle’ provides that works that contravene conditions precedent cannot be taken as lawfully commencing development.

In Ellaway, the court dismissed a challenge to an authority’s decision not to take enforcement action in respect of development which was commenced without lawful compliance with the pre-commencement conditions.


Ellaway v Cardiff County Council (2014), [2014] EWHC 836 (Admin)

In taking the decision not to enforce against the unlawful commencement of development, the authority had relied on a well-established exception to the Whitley principle, which provides that works undertaken prior to formal approval may lawfully commence a development where the application is made before the expiry of the relevant planning permission, the works undertaken accord with the submitted details and approval is subsequently granted. It recognised that approval should be granted retrospectively in relation to an EIA development only in exceptional circumstances. The court in Ellaway considered that exceptional circumstances justified retrospective approval of the discharge of the conditions.

Retrospective planning permission for EIA development

European Union law permits the lawful grant of retrospective planning permission for EIA development so long as:


R (Ardagh Glass) v Chester City Council [2010] All ER (D) 208 (Jun)

  • the grant makes common sense
  • the need to ensure that measures to ensure compliance with the Council Directive are proportionate and in accordance with European Union law, and
  • the ECJ's judgment in Commission v Ireland C-215/06 (unreported), which expressly recognised that, subject to certain conditions, national law might permit regularisation of unauthorised EIA development is considered

In addition, once an enforcement notice is issued, the existing procedures ensure compliance with Council Directive 85/337/EEC (on the assessment of the effects of certain public and private projects on the environment).

In Commission of the European Communities v Ireland (C-215/06) [2009], as confirmed by Padden v Maidstone Borough Council [2014] All ER (D) 140 (Jan), the judge considered that retrospective permission for EIA development should only be granted:

  • first in exceptional circumstances, and
  • second if the developer does not obtain any improper advantage from the pre-emptive development

Immunity from enforcement

In Evans v Basingstoke [2013] EWCA Civ 1635, the Court of Appeal considered whether a change of use which would have required an environmental impact assessment (EIA) could become immune from enforcement action. The appellants argued that the time limits must be disapplied in EIA cases otherwise the EIA development would obtain immunity without having its environmental impact assessed. The court held that in fact it was well established in EU law that there could be time limits for the taking of action as an expression of the need for legal certainty. The time limits in the domestic enforcement regime did not make it excessively difficult to secure compliance with the EIA Directive.

Compensation as an alternative to carrying out an EIA

In Wells, the ECJ noted that failure to comply with the EIA Directive could, if the affected individual agreed, be dealt with by way of compensation.


Wells v Secretary of State for Transport, Local Government and the Regions Case C-201/02, [2005] All ER (EC) 323

Stages of EIA

There are five broad stages to the EIA process:

Procedure for submitting an environmental statement

The procedure for preparing and submitting an environmental statement, and determining an application for EIA development, is summarised as follows:

  • preliminary consultations
  • content of the environmental statement
  • statutory and other consultees; the general public
  • techniques of assessment; sources of advice
  • submission of environmental statement with planning application
  • handling by the planning authority
  • requests for further information
  • determination of application
  • appeals and call-ins

See Practice Notes: Preparing an environmental statement and Procedure for submitting and determining an environmental statement.

Where a valid planning application and ES have been received by the LPA, the LPA has 16 weeks to determine the application, beginning with the day immediately following receipt of the application and ES, although the period may be extended by written agreement between the LPA and the applicant.


Town and Country Planning (Environmental Impact Assessment) Regulations 2011, SI 2011/1824, reg 61(2)

Town and Country Planning (Environmental Impact Assessment) (Wales) Regulations 2016, SI 2016/58, reg 57

The Town and Country Planning (Environmental Impact Assessment) Regulations 2017, SI 2017/571, reg 68

The Town and Country Planning (Environmental Impact Assessment) (Wales) Regulations 2017 SI 2017/567, reg 61

Environmental considerations

The list of aspects of the environment which might be significantly affected by a project is set out in Schedule 4 of the EIA Regulations, and includes population, human health, biodiversity (for example fauna and flora), land (for example land take), soil (for example organic matter, erosion, compaction, sealing), water (for example hydromorphological changes, quantity and quality), air, climate (for example greenhouse gas emissions, impacts relevant to adaptation), material assets, cultural heritage, including architectural and archaeological aspects, and landscape.


The Town and Country Planning (Environmental Impact Assessment) Regulations 2017, SI 2017/571, reg 18 and schedule 4

The Town and Country Planning (Environmental Impact Assessment) (Wales) Regulations 2017 SI 2017/567, reg 17 and schedule 4

Town and Country Planning (Environmental Impact assessment) Regulations 2011, SI 2011/1824, Sch 4

Town and Country Planning (Environmental Impact Assessment) (Wales) Regulations 2016, SI 2016/58, Sch 4

Consideration should also be given to the likely significant effects resulting from the construction and existence of the development, from the use of natural resources, from the emission of pollutants, noise, vibration, light, heat and radiation, the creation of nuisances, and the disposal and recovery of waste, and risks to human health, cultural heritage or the environment. .

The ES must cover direct and indirect, secondary, cumulative, trans-boundary, short, medium and long-term, permanent and temporary, positive and negative effects where these are significant.

See Practice Note: Environmental impact assessment—screening and scoping.

The Rochdale Envelope

The 'Rochdale Envelope', named after Rochdale MBC ex parte Tew [1999] 3 PLR 74 and Rochdale MBC ex parte Milne [2001] 81 PCR 27 (not available in Lexis®Library) is a principle which allows a project description to be broadly defined, within agreed parameters, for the purposes of a planning application. It provides flexibility for development consents when the final form of a project cannot be defined. As the development progresses and more detail is known, further information regarding significant effects of the project can be provided.

The Infrastructure Planning Commission (IPC), citing the Encyclopaedia of Planning Law and Practice, summarises the implications of the Rochdale Envelope for development consent order applications. Although the IPC has now been abolished, the guidance is maintained. The principle applies equally to the town and country planning regime. It states that:


Using the 'Rochdale Envelope'

  • an application should acknowledge the need for details to evolve over a number of years, within clearly defined parameters and the EIA must take account of this and reflect the likely significant effects of such a project
  • the permission must create 'clearly defined parameters' and the LPA can impose conditions on the outline permission to ensure that the process of evolution remains within the parameters
  • the level of detail of the proposal, within the defined parameters, must be such as to enable a proper assessment of the likely environmental effects, and necessary mitigation
  • the assessment may conclude that a particular effect may fall within a fairly wide range. In assessing the 'likely' effects, it is entirely consistent with the objectives of European Council Directive 85/337/EEC on EIA (now replaced by EU Directive 2011/92/EU) to adopt a cautious 'worst case' approach: mitigation measures should be adequate to deal with the worst case so as to optimise the effects of the development on the environment
  • the flexibility is not to be abused and does not give developers an excuse to give inadequate descriptions of their projects
  • it is for the LPA to determine what degree of flexibility can be permitted in the particular case having regard to the specific facts of an application. It is prudent for developers and LPAs to ensure they have assessed the range of possible effects implicit in the flexibility provided by the permission

By way of example, the Rochdale envelope could apply, in the case of offshore wind farms, to the structural components of the turbine, eg rotor diameter and speed, the physical footprint of the device, the design and layout of an array and construction and deployment methods, etc.

The level of flexibility may be a contentious issue between developers, who are likely to want as much flexibility as possible, and regulators, who need to narrow the scope to the extent that they are able to undertake an accurate EIA.

Challenging an EIA decision—discretion to quash

Need for substantial prejudice

As referred to in Champion, normally for a claimant to succeed in quashing a decision, they must have been ‘substantially prejudiced’ by the failure to comply with the statute's procedural conditions. Under both substantive and procedural grounds of review, the courts have a residual discretion not to quash a decision where there has been no prejudice or detriment to the claimant and to refuse relief in exceptional circumstances. This approach was approved by Lord Carnwath in Walton and Edwards.


Walton v Scottish Ministers [2012] UKSC 44

Edwards v Environment Agency [2008] UKHL 22

Cannot retrospectively dispense with EIA requirement where outcome would be no different

The substantial prejudice principle was applied in an EIA context by the House of Lords in the case of Berkeley, which established that the court was not entitled retrospectively to dispense with the requirement of an EIA on the ground that the outcome would have been the same or that the LPA or Secretary of State had all the information necessary to enable them to reach a proper decision on the environmental issues.


Berkeley v Secretary of State for the Environment Transport and the Regions [2001] EWCA Civ 1012

Lord Hoffman held that:

'The Directive prescribed a particular procedure which was to be followed. In the absence of at least substantial compliance, the court should not exercise its discretion to validate retrospectively a breach of the Directive, even if satisfied that the result would have been the same. Although section 288(5)(b), in providing that the court ‘may’ quash an ultra vires planning decision, clearly confers a discretion upon the court, I doubt whether, consistently with its obligations under European law, the court may exercise that discretion to uphold a planning permission which has been granted contrary to the provisions of the Directive. To do so would seem to conflict with the duty of the court under article 10 (ex article 5) of the EC Treaty to ensure fulfilment of the United Kingdom’s obligations under the Treaty.'

Can only quash if outcome would be different

The German case of Gemeinde on procedural errors in public law challenges held that members states’ discretion under the EIA Directive is sufficient to allow a 'causal link' provision, ie if a decision is to be successfully challenged on the basis of a procedural error, there must, in the circumstances of the case, be a definite possibility that the contested decision would have been different without the procedural error.


Gemeinde Altrip v Land Rheinland-Pfalz [2013] All ER (D) 102 (Nov)

In the UK, such a causal link is now contained in statute. Section 84 of the Criminal Justice and Courts Act 2015 inserted provisions into section 31 of the Senior Courts Act 1981 to provide that:

'(2A) The High Court— (a) must refuse to grant relief on an application for judicial review, and (b) may not make an award under subsection (4) on such an application, if it appears to the court to be highly likely that the outcome for the applicant would not have been substantially different if the conduct complained of had not occurred.

(2B) The court may disregard the requirements in subsection (2A)(a) and (b) if it considers that it is appropriate to do so for reasons of exceptional public interest.'

The ECJ confirmed that it was not necessary that all defects in EIA could give rise to a challenge. However, the burden of proof in showing that the result could have been different were it not for the error could not be placed upon the applicant, as this could make the exercise of rights conferred excessively difficult.

Gemeinde was about a rule of standing, rather than remedial discretion, but is consistent with the conclusions of Lord Carnwath in Walton, establishing that courts can refuse to quash a decision where 'the applicant has been able in practice to enjoy the rights conferred by the European legislation'. However, it is necessary for courts to ensure that the burden of proof does not fall on the party challenging the decision, but instead upon the defendant who asks the court to exercise its discretion not to quash.

EIA and the Habitats Directive

The 'appropriate assessment' requirements of the Habitats legislation will not be satisfied by undertaking EIA of a proposed development project. While it may be both possible and advantageous to undertake both assessments in tandem (eg by including the Habitats assessment within the environmental statement (ES) produced for the EIA), the European Court of Justice (ECJ) has emphasised the differences between the two regimes, and care must be taken to ensure that the specific requirements of both are, where necessary, satisfied.


Habitats Directive 92/43/EEC

Commission v Ireland Case C-418/04, [2007] ECR I-10997 at [230]–[231]

The EIA Regulations provide that where an EIA and appropriate assessment under the Habitats legislation is required, the decision-maker must ensure the procedures for both sets of assessments are coordinated, where appropriate.


The Town and Country Planning (Environmental Impact Assessment) Regulations 2017, SI 2017/571, reg 27

The Town and Country Planning (Environmental Impact Assessment) (Wales) Regulations 2017 SI 2017/567, reg 26

See: Environmental Impact Assessment and the Habitats Directive.

EIA and Nationally Significant Infrastructure Projects

Separate Regulations apply in relation to EIA requirements for Nationally Significant Infrastructure Projects seeking a Development Consent Order under the Planning Act 2008. See Practice Notes: Environmental impact assessments and Development Consent Orders and Application procedure for nationally significant infrastructure projects.


Infrastructure Planning (Environmental Impact Assessment) Regulations 2009, SI 2009/2263

Infrastructure Planning (Environmental Impact Assessment) Regulations 2017, SI 2017/572

PINS: EIA - Screening, Scoping and Preliminary Environmental Information - Advice note seven

PINS: EIA Consultation and Notification - Advice note three: The Planning Inspectorate and nationally significant infrastructure projects