[4] [1] The coastal plain is a 30-kilometre-wide (19 mi) strip on the Indian Ocean coast directly west of the Darling Scarp uplands running from Cape Naturaliste in the south to north of the city of Perth.

A number of rivers cross the plain from east to west from the Darling Scarp towards the sea, including the Swan and its main tributary, the Canning.

On reaching the Swan Coastal Plain, they encounter two obstacles: firstly, the high permeability of the soil results in the loss of much water.

For example, on reaching the coastal plain, Ellen Brook runs south for around 30 kilometres (19 mi), picking up a number of watercourses along the way, before finally emptying into the Swan River.

[7] Early work on all three dune systems considered them to have been formed at differing times by the deposition of sands carried by wind (aeolian and/or by river processes (fluviatile).

The south west region of Western Australia was one of the first places on earth to experience the effects of human induced climate change, namely a significant decline in annual rainfall.

The traditional flora of the dunes and the fairly infertile plain was dense shrubby kwongan heathland adapted to the poor soils, dry summers, and regular fires.

Kwongan vegetation contains a large number of endemic plant species, especially shrubs and wildflowers, including yellow flame and toothbrush grevilleas, fan-flowers, and cockies' tongues.

The coastal plains skink, discovered in 2012, is endemic to sand dunes in the area, and is threatened by residential development.

Although some areas are protected, clearance is going on while the plant disease Phytophthora dieback and changes to traditional fire regimens affect the heathland vegetation including the Banksia trees.

Traditionally, this area was under the care and control of the Yued, Whadjuk, Binjareb, and Wardandi Noongar peoples, whose hunter-gathering firestick farming practices maintained the climax vegetations old growth forests observed at the time of first contact.

Lake Monger was originally part of a series of freshwater wetlands running north from the Swan River along the coastal plain for about 50 kilometres (31 mi).

Many of these lakes formed a natural interconnected drainage system which found its way into the Swan River at East Perth through Claise Brook.