Sites of Special Scientific Interest.
The country’s best wildlife and geological sites. Development affecting an SSSI — or its hydrology and setting — triggers consultation with Natural England and a high bar where harm is likely.
- Schemes with no likely effect on features
- Robust mitigation and biodiversity net gain
- Sensitive recreation / access management
- Works improving the site’s condition
- Development within an impact-risk zone
- Schemes affecting hydrology or air quality
- Increased recreational pressure
- Lighting and noise near sensitive habitats
- Direct loss of SSSI habitat
- Harm to notified features
- Damage to geological exposures
- Unmitigated hydrological change
SSSIs are notified by Natural England under the 1981 Act for their flora, fauna, geological or physiographical features. Natural England is a statutory consultee on development likely to affect a site, and its impact-risk zones mean even schemes some distance away can trigger consultation where they affect hydrology, air quality or recreation pressure.
NPPF directs that development likely to harm an SSSI should not normally be permitted unless the benefits clearly outweigh both the impacts on the site and any broader network of national sites. For the most sensitive sites, an exception test and robust mitigation are needed — so early ecological survey is essential.
On or near an SSSI, ecology leads the scheme. Survey early, understand the impact-risk zone, and design to avoid likely significant effects before fixing the layout.
Schemes that arrive with Natural England already engaged and credible mitigation in place are in a completely different position from those that treat ecology as a late-stage report.
How schemes actually fare inside this designation — approval rates, appeal survival, which authorities apply it hardest — needs the designation joined to the decision record. That join isn’t built, so those figures aren’t published here. We won’t estimate them.
The Atlas maps SSSIs and their impact-risk zones against INSPIRE parcels. Check whether your site triggers Natural England consultation.