The report, by researchers at the University of NSW, found waste water was constantly flowing into the river through broken and leaking sewers.

Peter Stevens from Wolli Creek Preservation Society said the tragedy was that it was well known the river was being polluted by the sewerage system.

‘‘The issues are known,’’ Mr Stevens said. ‘‘But it has just been a matter of the state government not getting to fixing it.’’

Mr Stevens said community groups had done their best to improve the river’s health but had been let down by the government.

‘‘The community has put in heaps and heaps of time improving the surrounds of the river and testing the water but there are some things the community can’t do, like fixing the sewerage system,’’ he said.

The Leader asked NSW Environment Minister Robyn Parker whether the government planned to fix the sewerage system but did not receive a response before going to press.

A spokeswoman for Ms Parker pointed to a now defunct program rolled out by the previous Labor government, the Cooks River Sustainability Initiative, and $2 million granted in 2008 by the federal government under former PM Kevin Rudd, as examples of state government efforts to improve the river, but did not outline new funding or plans.

‘‘The NSW government recognises the important role of the Cooks River Alliance — a group that involves eight local councils — to continue the environmental management and preservation of the Cooks River,’’ the spokeswoman said.

South West Enviro Centre vice-president Gary Blaschke has lived near the river for 50 years and manages a wetland system upstream at Chullora.

He said $6 million in funding was needed to clean up the river.

‘‘Up until now there has just been tokenistic stuff done,’’ Mr Blaschke said.

‘‘[The river] has been used and abused by every government that’s been around and it’s been neglected by every government.’’

He said the river needed a series of offline wetlands to filter and purify water.

Are you concerned about the state of the Cooks River?