Glossary: S

Scottish Environment Protection Agency (SEPA)

The Scottish Environment Protection Agency is responsible for the protection of the environment in Scotland.

Site of Special Scientific Interest (SSSI)

SSSIs are the country’s very best wildlife and geological sites.

Shrink-swell

Shrinking and swelling of the ground (often reported as subsidence) is one of the most damaging geohazards in Britain today. Many soils contain clay minerals that absorb water when wet (making them swell), and lose water as they dry (making them shrink).

Soluble Rocks

Ground dissolution occurs when water passing through soluble rocks produces underground cavities and cave systems. These cavities reduce support to the ground above and can cause localised collapse of the overlying rocks and deposits.

Source Protection Zone (SPZ)

Defined by the Environment Agency, SPZs show the risk of contamination from any activities that might cause pollution to groundwater resources. The size and shape of an SPZ depends on the surrounding environmental factors. SPZs are split into 3 zones depending on the distance and how many days it would take any pollution to reach to the borehole.

Special Areas of Conservation (SACs)

Special Areas of Conservation are strictly protected sites designated under the EC Habitats Directive.

Special Protection Areas (SPAs)

Special Protection Areas are strictly protected sites classified in accordance with Article 4 of the EC Directive on the conservation of wild birds (79/409/EEC), also known as the Birds Directive, which came into force in April 1979.

Statutory Water Quality Objectives (SWQOs)

For each stretch of a river the Environment Agency establishes a river quality objective. This reflects the uses to which the waters are put and is the basis for deciding the discharges which can be allowed.

Subsidence

The motion of the Earth’s surface as it shifts downwards. Subsidence usually happens when problems occur with houses built on clay soils, or when water leaks into soil.

Surface Water Abstraction Licence

A licence authorised by the Environment Agency to divert surface water for a designated purpose, such as irrigation or potable water supply.

Surface Water Flooding

Ambiental Risk Analytics surface water (pluvial) FloodMap identifies areas likely to flood as a result of extreme rainfall events,typically this is topography low spots which are naturally vulnerable to surface water ponding or flooding.