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SSSI Definition: What is it and what does it mean for conservation and development?

A Site of Special Scientific Interest (SSSI) is a formal conservation designation for an area which is of particular interest because of its fauna, flora or geological or physiological features; in other words, these areas have extremely high conservation value.

The designation could be due to the presence of rare species or geological and physiological features. An SSSI can also be designated to give higher levels of protection over other designations that might be given to an area of land such as Areas of Outstanding Natural Beauty (AONB’s).

SSSIs are designated by an official authority. In England this is Natural England, in Wales the official authority is Natural Resources Wales, in Scotland it is Scottish Natural Heritage and in Northern Ireland it is the Northern Ireland Environment Agency. Northern Ireland SSSI’s are referred to as Areas of Special Scientific Interest (ASSIs).

SSSIs contain important habitats such as grasslands, parkland and woodland with some containing ancient woodland and ancient trees.

We estimate that in England, around 17% of ancient woodland listed on the Ancient Woodland Inventory (which, importantly, is incomplete) enjoys protection as a result of being within an SSSI designated area. Unfortunately, even SSSI status is enough protection to ensure ancient woodland are completely safe from development.

Visit an SSSI

Many SSSIs feature ancient woodland and are open for you to go and visit:.

Aversely Wood – Cambridgeshire

Aversley Wood

Cambridgeshire is the least wooded county in the UK, with just over 2% woodland cover and less than 1% ancient woodland which makes this ancient wood incredibly special. It has plentiful birdlife and a fantastic bluebell display each year.

Harpsden and Peveril Woods – Oxfordshire

Harpsden & Peveril Woods

This is another fantastic ancient broadleaved woodland. The wood is dominated by mature beech, pedunculate oak, ash trees and sessile oak as well as many other tree species as well as uncommon orchid species.

Can you build on an SSSI?

Building works and development can often disturb the very reason the SSSI was designated. Therefore, permission needs to be granted by the designating body for works to go ahead.

Certain works are exempt from these planning applications, for example when the work is an emergency. In the majority of cases permission from the designating body isn’t enough and planning permission will also need to be sought. The plans will often require survey work to be completed to assess the potential damage that could occur to the SSSI during the building work and once the works are completed.

When development is proposed on ancient woodland or in areas with ancient trees that are designated as SSSI we will challenge it, as we do with all potential threat to these irreplaceable habitats.

Help us fight development that will impact ancient woodland and or ancient trees by supporting our Enough is Enough campaign