Rainham, Wennington and Aveley Marshes (EHER 48399)

An extensive area of surviving grazing marsh, situated to the south of the A13 and CTRL, and adjacent to the River Thames to the south. The area now forms the RSPB’s Rainham Marshes reserve. The marsh has numerous sinuous boundaries, representing the lines of former creeks, and extensive military structures remaining from the WWI Purfleet rifle range, and later Second World War anti-aircraft defences, although a significant number of these structures have been demolished, following archaeologically recording. The area was part of ‘Rainham level’ during the medieval period. Current land use within the reserve is grazing and nature conservation. The marsh is dominated by common grasses, but includes a number of nationally rare species such as divided sedge Carex divisa, which is extensive.

2014. Historic Grazing Marsh Project. Historic environment character: The marsh is considered medieval in origin, and was certainly completed by the time of the Chapman and Andre map of 1777 <1>, with a small area along the southern boundary added between 1799 and 1837. During the late medieval period the marsh was part of ‘Rainham Level’. The area retains its physical association with the River Thames to the south, and Mardyke to the east. The 1st edition OS map <2> shows a number of sheepfolds dotted across the marsh, together with track-ways. The sea wall survives on the southern side along the line shown on the 1st edition map. The area also encompasses the former channel of Wennington Creek. Drainage ditches throughout the area retain a sinuous form highlighting their origin as creeks. Areas of stetch cultivation are evident from aerial photographs and some parts of the marsh have been affected by the RSPB’s efforts to increase wetland habitat on its reserve. There are significant earthworks and built structures associated with the Purfleet rifle ranges and later anti-aircraft defences dating to the Second World War. Modern reserve infrastructure includes a visitor centre, multi-user paths etc. The marsh is mainly grazed but there are some un-grazed areas. Character of vegetation: Mix of ungrazed and grazed areas. Nationally rare divided sedge Carex divisa extensive. Marshes dominated by common grasses such as red fescue Festuca rubra, meadow foxtail Alopecurus pratensis, crested dog's-tail Cynosurus cristatus and perennial rye-grass Lolium perenne. Wet drains dominated by common reed Phragmites australis, contain locally rare aquatic species such as lesser pondweed Potamogeton pusillus and threadleaved water-crowfoot Ranunculus trochophyllous; and nationally rare soft hornwort Ceratophyllum sumbersum and brackish watercrowfoot Ranunculus baudotii. One creek contains stiff-saltmarsh grass Puccinellia rupestris, a rare plant only known in the London region from this and a few neighbouring sites. The pond/depression contains nationally rare species such as saltmarsh rush Juncus gerardii and marsh dock Rumex palustris. Threats: The biodiversity of the area managed by the RSPB for nature conservation is unthreatened, but the historic environment of the reserve could be negatively affected by nature conservation, or recreational impacts, as it has been in the past during the creation of the reserve and its infrastructure. Thames 2100 Rainham Marshes Policy Unit: potential impact on historic environment resulting from required enhancements to drainage system on marshes, including local fluvial flood storage. Front runner choice of Option 2 (Flood storage) in 2070 would result in loss of the grazing marshes. See <3>.