· The River
The Mardyke is a long, slow flowing river, with a gradient of approximately 1:7500 (which is very low!). As a wildlife habitat , it suits species adapted to inhabit both still and slow flowing aquatic environments. However, in the wetter winter months, the level of the Mardyke frequently rises dramatically, with the river bursting its banks and providing suitable habitats in the flood plain/water meadows for species adapted to periodic flooding.

· The Flood Plain
The flat low lying land running along side the river comprises the flood plain. This land is flooded most winters and during wet weather acts as a useful area to store flood waters that would otherwise flow into the Thames and contribute to flooding elsewhere where the effects may be damaging.

· The River Valley
The flood plain lies at the bottom of a relatively steep sided valley, the Mardyke Valley! In the area of Davy Down the valley sides are covered in fabulous ancient woodland.