The Cooks River, a semi-mature tide-dominated drowned valley estuary,[1] is a tributary of Botany Bay, located in south-western Sydney, New South Wales, Australia.

It serves as part of a stormwater system for the 100 square kilometres (39 sq mi) of its watershed, and many of the original streams running into it have been turned into concrete lined channels.

It reaches its northernmost point at Strathfield, where it leads into a concrete open canal, no more than one metre wide and thirty centimetres deep.

The League recommended cleaning up the river by developing a canal system and removing of the footings of Tempe Dam, proposal which had been made originally by engineer H B Henson, in 1896.

[2] Selected areas of the Cooks River which is lined with concrete will be replaced in 2013 and 2014 with a more natural bank with sandstone rocks and indigenous planting.

The Alliance combines and builds resources, experience, knowledge and skills within councils and communities, to work on complex environmental challenges.

It is generally thought that four different clans, each speaking a distinct dialect of the Darug language, inhabited the area surrounding the river.

whilst on the northern side, it is generally thought that the Gameygal clan lived between the mouth of the Cooks River and the ocean.

Further west, the river was used by the Cadigal people (whose country extended north up to Port Jackson and took in the area where modern-day Sydney is now located).

In 1770, Captain Cook sailed into Botany Bay and made the first written description of the river as follows: "I found a very fine stream of fresh water on the north side in the first sandy cove within the island before which a ship might lay land-locked and wood for fuel may be got everywhere.

The first land grants along the river tended to be fairly large and used mostly for grazing and timber with some fishing and lime burning at Botany Bay.

Governor Macquarie makes reference to a slender bridge in his 1810 diary, adding that "the soil is bad and neither good for tillage or pasturage".

Despite the increasingly doubtful quality of the water, the river remained a popular place in the late nineteenth century for boating, picnics and swimming.

In 1894, artist Sydney Long painted an idyllic scene of boys swimming in the Cook's River, entitled By Tranquil Waters, which was so well received that it was bought by the Trustees of the Art Gallery of New South Wales.

[13] Initiatives from 1976 onwards have attempted to preserve and return the natural features of the river system with tree planting, pollution traps and landscaping.

[5] In November 2007 the Federal Australian Labor Party, then in opposition, made an announcement of A$2 million for environmental projects on the Cooks River.