Crossness Nature Reserve

About

Crossness Nature Reserve is a 25.5 hectare local nature reserve in Crossness in the London Borough of Bexley. It is part of the Erith Marshes Site of Metropolitan Importance for Nature Conservation. The site is adjacent to Crossness Sewage Treatment Works; the works form the reserve's western boundary. It was created under a planning condition (Section 106 agreement) in 1994 and is owned and managed by Thames Water. At the northern edge of the reserve is a waste management facility owned and operated by Cory.

Crossness is part of the original Thames floodplain called Erith Marshes. It is one of the few remaining areas of grazing marsh in London, and it has the largest reedbeds in Bexley. It also has ponds and ditches, and areas of scrub and rough grassland. It is a major site for water voles, and 130 species of birds have been recorded, together with some rare invertebrates, including five species of water beetles and one of the UK's rarest wild bumblebee species, the Shrill Carder bee. Scarce plants include Borrer's saltmarsh grass and frog rush, a species that was previously thought to be extinct in Kent.