River Mardyke

The Mardyke is a small river situated in the south of Essex in the borough of Thurrock. Its headwaters lay between Great Warley and Little Warley at Holden’s Wood, and flows for around 17km before joining the River Thames at Purfleet.

Historically the Mardyke was a vital connection between the River Thames and the inland fens to the northeast of the county.

This map shows the completed walkovers for the River Mardyke.

Click or tap a pin to see details of a walkover

There is a water treatment plant present on this stretch of river and there appears to be a possible channel diversion around this so it becomes very straight. However, along other parts of this stretch it is more natural with meanders present. The channel can become choked with large amounts of vegetation with some large reed beds in places. There are good buffer strips of vegetation separating the arable land from channel.

The channel has been straightened and is quite narrow and featureless here, with very steep banks that are undercut in places. Surrounding land is mainly arable fields. There are a network of ditches at the furthest point upstream.

The channel is straightened, featureless and narrow at this point with some in channel reed present. Buffer strips are located on either side of the river creating some separation between the channel and the arable fields, a ford and a bridge are also present.

The surrounding land is arable fields. The channel becomes less straightened and more natural further upstream and there are buffer strips of vegetation on both banks separating the arable land from the channel. At the time of the survey the buffer strips consisted of a variable mix of herbs.

The surounding land is arable fields with some shading from trees but the channel is mainly open. There are buffer strips of vegetaion on both banks separating the channel from the arable land. There was also some in channel vegetation at the time of the survey.

The channel has been straightened and reprofiled in the past.

The surrounding land consists of arable fields and paddocks. There was good vegetation along both banks at the time of the survey.

There was some shading from bankside trees and scrub, with good margin plants and some in channel vegetation at the time of the survey.

The bankside habitat is a mixture of woodland one side and pasture, arable land and woodland on the other side. There are more features present in the channel than areas downstream.

At the time of the survey horses were being grazed in the pasture areas.

This stretch of river is predominantly grassland, some of which is grazed by horses. There is footpath access along the south bank, and the river channel itself has been modified in the past.

This area is run by the Davy Down Trust. It is managed for wildlife and as a public open space.

This area is a combination of amenity grassland, scrub, woodland and semi to unimproved grassland. The channel has been straightened and dredged in the past.

There is some trampling along the bank but this is from dogs as this is a popular dog walking area.

This stretch of river and bankside pasture is owned by Thurrock Council and a grazier grazes his horses here. The area suffers from erosion and fly tipping issues, and previous attempts at reedbed creation have not been successful, although in some fenced areas scrub has developed to provide habitat for birds. The area is very open with very few trees and herbs along the banks.

This stretch of river is adjacent to grazing pasture owned by Thurrock Council and managed by a grazier who grazes horses here. The channel has been straightened and reprofiled in the past, and has issues with trampling and overland runoff, as well as potential pollution problems.

This land is owned by Thurrock Council and a tenant grazier grazes his horses here. This stretch of river is surrounded by pasture land. Previously there have been attempts to create habitat such as reedbeds for wildlife, but these efforts have been unsuccessful and are now causing issues with overland runoff, which may be leading to contamination issues within the Mardyke.

This land is owned by Thurrock Council but a tenant grazier grazes his horses here. The area has little bankside vegetation, and the banks are heavily trampled, causing collapsed banks in some areas.

At the time of the survey there were bundles stored on the banks and were suspected to be rubbish from a landfill site and a possible source of contamination.

This section lies between a busy road bridge over Tank Hill Road to the West and a railway bridge to the East. It is a relatively short stretch of river through a fairly industrialised area, but is adjacent to areas with high wildlife potential. One bank has recently been planted with trees and a reedbed created.

The channel is canalised and reinforced with scrub along both banks after the sluice gate. Due to the dense scrub the channel and bank are very shaded, which is probably one of the factors that is preventing the growth of in channel vegetation. The channel is straight and generally featureless and there is little connection between bankside and in channel habitats due to the reinforcement along most of the stretch.

Website key stakeholders:

Environment Agency logo      Essex Wildlife Trust logo           ESWT Logo 70

Design by LTD Design Consultants and build by Garganey Consulting based on an original concept by Herts and Middlesex Wildlife Trust