Habitats Regulations Appraisal (HRA): appropriate assessment

An assessment of impacts, using the conservation objectives – is there no adverse effect on site integrity? 

For a competent authority to approve a proposal, it must carry out an appropriate assessment (AA) and this must clearly show that the plan or project won’t adversely affect the site’s integrity.

What is an appropriate assessment?

An AA can be broken down into two distinct phases:

  1. a scientific appraisal of all the likely significant effects of the plan or project on the relevant qualifying interests of a European site, based on the site's conservation objectives
  2. a decision-making process based on the conclusions of this appraisal – i.e. coming to a conclusion about the integrity of a European site

Checking for a plan or project’s likely significant effects on a European site determines whether an AA is required.

An AA isn’t required if the plan or project is directly connected with – or essential to – nature conservation management. This derogation relies on the plan or project promoting the conservation objectives of the European site and it must take into consideration all features on the site.

How to conduct an appropriate assessment

Deciding if a proposal will not have an adverse effect on site integrity calls for scientific judgement. A competent authority may ask the applicant for any information necessary to inform an AA.

An appropriate assessment should:

  • focus exclusively on the qualifying interests of the European site
  • clearly use the site's conservation objectives to help conduct the appraisal

Conservation objectives for each site can be found on SiteLink, for SACs these are within the Conservation Advice Packages (CAPs) or Conservation and Management Advice Documents (CMAs).

The assessment should be based on – and supported by – evidence that can stand up to scientific scrutiny. It must be detailed and robust enough to answer the question “Can it be ascertained that the integrity of the European site will not be adversely affected?” European case law* confirms that, in order to conclude a lack of adverse effects, there must be no reasonable scientific doubt about their absence.

A hierarchy of consents and/or assessments may apply to a proposal. If so, the Habitats Regulations Appraisal (HRA) must be revised and updated to take account of recent developments, changes or information. This helps to ensure that you assess the potential impacts on European sites at every relevant stage.

* Note that following the UK’s departure from the European Union rulings from the European Court of Justice remain in force as though made by the Supreme Court.

Concluding no adverse effects

The competent authority must be sure – by means of the AA – that the plan or project will have no adverse effect on site integrity (including any potential cumulative effects). This reflects the degree to which the precautionary principle is written into law via the Habitats Regulations.

There are no concrete rules about what constitutes ‘no adverse effect on site integrity’. Each case should be judged on its own merits. Previous legal judgements can help you to correctly interpret the legislation.

Mitigation of potential impacts on site integrity can be used in an AA to support a conclusion of no adverse effects on site integrity. But note that ‘mitigation’ and ‘compensatory measures’ are two quite different things in the HRA context. Case law has established that compensatory measures cannot be used to support a conclusion of no adverse effect on site integrity. The Briels case (European Court of Justice C-521/12) somewhat clarifies this issue.

A competent authority may also set up a legally enforceable framework (e.g. conditions) to ensure no adverse effect on the integrity of a European site.

Consenting a proposal with potential to adversely affect site integrity

A competent authority may wish to consent a proposal despite the potential for an adverse effect on site integrity. Where this is the case, it must first show that there are no alternative solutions, and that it is imperative to public interest to grant consent.

Help and advice

Read further help and advice on Habitats Regulations Appraisal.

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