South of Portland MCZ

Status: Proposed


Site overview

The powerful Portland Race, a raging tidal flow that runs south and north past Portland Bill, has gouged the 100m Portland Deep into the soft seabed rock south of the Isle of Portland. This site includes the Deep and the marine wildlife that inhabits this unique geological feature. The crags and canyons eroded into the Portland Stone, the same stone that built St Pauls Cathedral, the Tower of London and Buckingham Palace, provide a home for a higher than average diversity of invertebrates that cling on in this dynamic habitat. Beyond the Deep lie blue mussel beds, providing a slightly more relaxed habitat for a variety of fish and invertebrates.

Designation of this marine conservation zone in 2019 will protect this unique site and its marine wildlife for future generations.

MPA Type

Marine Conservation Zone

Marine Conservation Zones (MCZs) are designated under UK legislation (Marine and Coastal Access Act 2009) and have been established around England, Wales and Northern Ireland to contribute to the UK MPA network protect a range of nationally important marine wildlife, habitats, geology and geomorphology, and can be designated anywhere in English and Welsh territorial and UK offshore waters.

Surface Area

17.49 km2 (6.75 mi.2)


18.00 km (11.19 mi.)

Seasearch Logo

Seasearch survey dives are planned for Summer 2018. This is a very challenging site to dive, being up to 80m deep (well beyond normal limits for recreational SCUBA divers) and subject to very strong tidal streams. It is notable for its geological feature (Portland Deep) and high diversity of life on the seabed.

Learn more about Seasearch

Did you know?…

Over 170 parliamentarians from across the political spectrum signed up to our Marine Charter calling for a network of ‘marine protected areas’ in UK Seas

Over 500,000 records on undersea habitats and species have been collected by volunteer Seasearch divers providing significant evidence for inshore ‘marine protected areas’

An area over 9 times the size of Wales is now in marine protected areas in the UK, but less than 1% is considered by MCS scientists to be well managed

Stop the plastic tide

Support our appeal to turn the tide on plastics.

Find out more