The Cooks River, a semi-mature tide-dominated drowned valley estuary, is a tributary of Botany Bay, located in south-eastern Sydney, New South Wales, Australia.
The course of the urban waterway has been altered to accommodate various developments along its shore. It serves as part of a stormwater system for the of its watershed, and many of the original streams running into it have been turned into concrete lined channels. The tidal sections support significant areas of mangroves, bird, and fish life, and are used for recreational activities.
Course
The river begins at Graf Park, Yagoona, then flows in a roughly north-easterly direction to Chullora. 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. It then heads towards the south-east. Where Cooks River runs through Strathfield Golf Course, the concrete lining has been partly removed. Here the plants have returned and have created an environment where the water is filtered and runs clean, and where wildlife has returned. One section here is called the Chain of Ponds.
At Belfield it joins with the Cox Creek Channel and flows in an easterly direction. The canal widens and deepens as it picks up stormwater from surrounding suburbs, such as Campsie and becomes influenced by tidal action.
At Canterbury, it is joined by Cup and Saucer Creek. Industrial areas line the Cooks River at Canterbury. In the past, factories discharged their waste directly into the water.
The valley becomes more pronounced as the river reaches Tempe, where it is joined by Wolli Creek and the Alexandra Canal. The Princes Highway crosses the Cooks River and links Tempe to the suburb of Wolli Creek. Also here is the low-lying Fatima Island, which is submerged at high tide.
The course of the final south-flowing section of river is entirely artificial. The river formerly flowed, via marshes, on a meandering course across the present site of Sydney Airport to meet Mill Stream and enter Botany Bay from the northern end of the bay. The boundary between the Parish of Botany and the Parish of St George remains at the former mouth of Cooks River. This part of the river course was altered to accommodate the expanding Sydney Airport. Cooks River now connects with Botany Bay at Kyeemagh.
The corridor of land beside the river is a conduit for many services along large parts of its length including electricity, high-voltage lines, a high-pressure oil pipe owned by Shell, and high-volume sewage pipes. Many of the lower-lying areas have been filled and are parks and sports grounds. In spite of this the river and adjacent lands are being recognised for their beauty, history, amenity and environmental value, if not also for potential for improvements. The walkway and cycleway beside much of the river is part of the path connecting Sydney Olympic Park with Botany Bay.
Management
Care and control of the river is shared between many local councils and the New South Wales Government through agencies such as the Sydney Metropolitan Catchment Management Authority, the Department of Planning & Environment and Sydney Water.
The river also has a number of community-based organisations which assist its maintenance, in particular the Cooks River Valley Association (CRVA). The CRVA grew from The Cooks River Improvement League, founded in 1925, which had published a book entitled "Our Ocean to Ocean Opportunity". 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.
In 2010 the Cup and Saucer Wetlands were built in Canterbury to create a natural environment for the native wildlife and fauna.
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.