Canvey Marsh (EHER 48412)

An area of marsh located on the south side of Canvey Island adjacent to an oil refinery. The marsh contains areas of both ‘improved’ grasslands and relict grazing marsh with fossilised creeks and earthworks or red hill salt making sites. Sites of two farmsteads with post medieval origins remain occupied, and there is evidence for ‘stetch’ cultivation or other surface drainage. A Second World War pillbox survives. A modern road (Roscommon Way) extension has reduced the northern extent of the western area of the march. The grassland is mainly improved but includes the nationally rare Stiff-saltmarsh grass Puccinellia maritima in its Western part.

2014. Historic Grazing Marsh Project. Historic environment character: The marsh was probably reclaimed, with the involvement of Dutch engineers, during the early 17th century, when it formed part of a larger area of reclamation on Canvey Island. The line of the sea wall survives along the southern western part of the marsh, although has been considerably altered. The marsh boundaries demarcate boundaries between several detached parishes. A large curving fleet survives as a body of water towards the centre of the marsh. The marsh includes the sites of at least two farms, including Brick House Farm, depicted on the 1st edition OS map, which remain in occupied today <1>. The area show signs of ‘stetch’ and includes straight drainage ditches. However sinuous ditches/fossilised creeks survive and the western side of the marsh includes the earthwork remains of one or more Roman red hills (salterns), one of which has also produced evidence for early Anglo-Saxon re-use. A Second World War pillbox (EHER 10798) survives as a standing structure. Today, the setting of the marsh has been largely compromised by housing development and an oil refinery. Character of vegetation: Semi-improved grassland dominated by Red Fescue Festuca rubra and Bentgrasses Agrostis spp. In Western half, Bird’s-foot trefoil Lotus spp. Is abundant and Red Clover Trifolium pretense and Strawberry Clover T. fragifera occur. Sea club-rush Bolboshoenus maritimus found along sea wall. Nationally rare Stiff-saltmarsh grass Puccinellia maritima also found in Western part. Threats: Potential threat from development See <2>.