Habitats Regulations Assessment (HRA)

Why do you need an HRA?

HRAs determine the ‘likely significant effect’ of any development on a designated Natura 2000 site protected under the Habitats Directive. Natura 2000 sites include Special Areas of Conservation (SACs), Special Protection Areas (SPAs) and Ramsar sites.

Impacts that may trigger an HRA include:

  • Increasing the number of residential units within 400m of an SAC/SPA
  • Increased recreational pressure
  • Discharges into watercourses
  • Noise or visual disturbance
  • Air or light pollution
  • Disturbance of species or habitats

What does an HRA involve?

HRAs have four stages: screening, Appropriate Assessment (AA), assessment of alternatives and consideration of Imperative Reasons of Overriding Public Interest (IROPI).


This looks at your development’s possible impacts on the integrity of the protected site or its qualifying features. We’ll provide a detailed assessment of construction- and operational-phase impacts that could have significant adverse effects on your site. If our assessment shows impacts are likely, an AA will be required. If no likely impacts are found, no further action will be needed. Single-unit or small home development projects can often be scoped out at the screening stage.

Appropriate Assessment

We’ll work with you to create a mitigation plan that avoids adversely impacting the protected site. Each impact we identify during screening will be subject to a full AA. Evidence showing avoidance and/or mitigation measures will be presented to the Local Planning Authority (LPA) for consideration.

Details will also be shared of any long-term management and maintenance that may be necessary to facilitate the measures, including funding. This is an in-depth report usually required for large developments.

Assessment of alternatives

Your assessment should identify and assess considered alternatives. For instance, a proposal of a different scale, a different location and an option of not having the scheme at all.

Consideration of IROPI

Where we can prove no alternative solutions would have a lesser effect on the integrity of the site, the project may still be carried out – but only if the competent authority feels the scheme must be carried out for imperative reasons of overriding public interest (IROPI). These could relate, for example, to human health, public safety or beneficial consequences of primary importance to the environment.