[10] Around 400 years ago the land was drained and converted to grazing marsh using a series of windpumps or windmills and drainage ditches.

[10][12] This led to the loss of wildlife habitat and in 1981 an area 1,430 hectares (3,500 acres) in size was designated as a Site of Special Scientific Interest.

[10] The villages of Reedham, Wickhampton and Halvergate and the higher ground they occupy forms the western edge of the marshes, with the market town of Acle at the extreme north-west.

The drainage ditches which cross the marshes are deemed to be of "outstanding importance for nature conservation" and support a range of freshwater and brackish communities of plants and invertebrates.

[13] Freshwater ditch communities, which lie mainly along the western side of the SSSI area, are recognised as being of "being of international importance" and support species such as broad-leaved pondweed Potamogeton natans, water violet Hottonia palustris and the nationally scarce whorled water milfoil Myriophyllum verticillatum.

The area of ditch close to Breydon Water are more brackish in nature and feature species such as soft hornwort Ceratophyllum submersum and the nationally scarce stiff saltmarsh grass Puccinellia rupestris.

[20] The Royal Society for the Protection of Birds takes a leading role in management on the marshes, working alongside other environmental bodies such as Natural England, Norfolk Wildlife Trust and the Broads Authority.

Farmers work in collaboration with environmental management agencies, for example to reinstate drainage ditches and dykes to support biodiversity on the marshes.