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Special Areas of Conservation

Essex Estuaries

Designated Special Area of Conservation (SAC)
Country England
Unitary Authority Essex, Extra-Regio
Centroid* TM103048
Latitude 51.70166667
Longitude 1.043611111
SAC EU Code UK0013690
Status Designated Special Area of Conservation (SAC)
Area (ha) 46109.95
* This is the approximate central point of the SAC. In the case of large, linear or composite sites, this may not represent the location where a feature occurs within the SAC.
Location of Essex Estuaries SAC

General site character

  • Marine areas, Sea inlets (30%)
  • Tidal rivers, Estuaries, Mud flats, Sand flats, Lagoons (including saltwork basins) (56.5%)
  • Salt marshes, Salt pastures, Salt steppes (11%)
  • Shingle, Sea cliffs, Islets (0.5%)
  • Improved grassland (2%)

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Note When undertaking an appropriate assessment of impacts at a site, all features of European importance (both primary and non-primary) need to be considered.

Annex I habitats that are a primary reason for selection of this site

  • 1130 Estuaries

    This is a large estuarine site in south-east England, and is a typical, undeveloped, coastal plain estuarine system with associated open coast mudflats and sandbanks. The site comprises the major estuaries of the Colne, Blackwater, Crouch and Roach rivers and is important as an extensive area of contiguous estuarine habitat. Essex Estuaries contains a very wide range of characteristic marine and estuarine sediment communities and some diverse and unusual marine communities in the lower reaches, including rich sponge communities on mixed, tide-swept substrates. Sublittoral areas have a very rich invertebrate fauna, including the reef-building worm Sabellaria spinulosa, the brittlestar Ophiothrix fragilis, crustaceans and ascidians. The site also has large areas of saltmarsh and other important coastal habitats.

  • Essex Estuaries represents the range of variation of this habitat type found in south-east England and includes the extensive intertidal mudflats and sandflats of the Colne, Blackwater, Roach and Crouch estuaries, Dengie Flats and Maplin Sands. The area includes a wide range of sediment flat communities, from estuarine muds, sands and muddy sands to fully saline, sandy mudflats with extensive growths of eelgrass Zostera spp. on the open coast. The open coast areas of Maplin Sands and Dengie Flats have very extensive mudflats and an unusually undisturbed nature. Maplin Sands is particularly important for its large, nationally-important beds of dwarf eelgrass Zostera noltei and associated animal communities.

  • Glasswort Salicornia spp. saltmarsh in the Essex estuaries on the east coast of England forms an integral part of the transition from the extensive and varied intertidal mud and sandflats through to upper saltmeadows. Although the saltmarshes in this area are generally eroding, secondary pioneer communities appear as a precursor to erosion on the seaward edge of degraded mid-marsh communities. The area of pioneer marsh includes gradation into extensive cord-grass Spartina spp. swards.

  • The most extensive remaining stand of the native small cord-grass Spartina maritima in the UK and possibly in Europe is found in the Essex Estuaries. The stand is located at Foulness Point and covers approximately 0.17┬áha. Other smaller stands are found elsewhere in the estuary complex, notably in the Colne estuary, where it forms a major component of the upper marsh areas.

  • Although the saltmarshes in this area are generally eroding, extensive salt meadows remain and Essex Estuaries represents Atlantic salt meadows in south-east England, with floristic features typical of this part of the UK. Golden samphire Inula crithmoides is a characteristic species of these marshes, occurring both on the lower marsh and on the drift-line. It represents a community of south-east England also found to the south in mainland Europe.

  • In this complex of estuarine marshes on the east coast of England the occurrence of Mediterranean and thermo-Atlantic halophilous scrubs is currently artificially restricted by sea-walls. It now occurs principally as a strandline community or at the foot of sea-walls. Recent managed retreat schemes offer the prospect of future expansion of the habitat type. The local variant of this vegetation, which features sea-lavenders Limonium spp. and sea-heath Frankenia laevis, occurs at one location, Colne Point.

Annex I habitats present as a qualifying feature, but not a primary reason for selection of this site

Annex II species that are a primary reason for selection of this site

  • Not Applicable

Annex II species present as a qualifying feature, but not a primary reason for site selection

  • Not Applicable

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