Save The Blue Mountains Wild Rivers

The proposal to raise the height of Warragamba Dam is unnecessary and environmentally destructive.

Raising the dam would destroy 65 kilometres of pristine wild rivers and drown 4700 hectares of Blue Mountains’ world heritage listed National Parks. The Kowmung River, one of NSW’s few remaining wild rivers, will be drowned under Lake Burragorang.

Lower Kowmung River


Warragamba Dam plan puts Blue Mountains World Heritage Area at risk: environmentalists

The Blue Mountains World Heritage Area is under threat if the state government’s plans to raise the Warragamba Dam wall proceed, environmentalists warn.

"Raising the dam will destroy unique environments within the Blue Mountains World Heritage Area, including the pristine Kowmung River wilderness,” said Harry Burkitt from the Colong Foundation.

Overflowing in 2013: Warragamba Dam, four years ago. Environmentalists are opposed to plans to raise the dam wall by 14 metres.

Overflowing in 2013: Warragamba Dam, four years ago. Environmentalists are opposed to plans to raise the dam wall by 14 metres.

"The Kowmung River is one of only six declared wild rivers in NSW, and it will be permanently scarred from inundation if the dam raising goes ahead.”

Ecologist and former Blue Mountains resident Roger Lembit said the rare Camden White Gum, a unique species of eucalpyt, which is primarily found in the proposed upstream inundation area, would be lost. 

Under threat: Raising the Warragamba Dam wall would destroy environments around the Kowmung River, environmentalists say. Picture: David Noble

Under threat: Raising the Warragamba Dam wall would destroy environments around the Kowmung River, environmentalists say. Picture: David Noble

“You can’t put them back. The conditions are not the same and the soil changes. Extra sediments change the soil chemistry and invertebrates in the soil are affected,” Mr Lembit said.

Animals would also be affected.


“Platypus in the area and wombats that live on the flood plain are particularly at risk,” Mr Lembit said.

The opportunity for weeds to be introduced and replace native plant communities, was also problematic, he said. 

“The proposal being pursued will impact on world heritage area values,” Mr Lembit said.

In June 2016, then Premier Mike Baird said the wall would be raised by 14 metres, as flood mitigation in the Hawkesbury-Nepean Valley.

 It "will offer significant extra protection for townships downstream, including Windsor, Richmond and parts of Penrith," Mr Baird told Fairfax Media at the time.

Construction, at an estimated cost of about $690 million, was expected to be complete within three years after a business case is signed off in 2020, subject to planning approvals.

Raising the dam wall is meant to reduce the impact of flooding thanks to a higher capacity to store water before the dam spills, however, it will not stop flooding completely.

There hasn’t been a significant flood event since 1990, but the dam did spill in 2015.

Mr Burkitt said the proposal was unnecessary, and other options should be considered.

"Constructing flood levies, pre-releasing dam water before floods, and not building new housing developments on floodplains are alternative measures that can be implemented at far less cost, while not destroying parts the most protected natural landscape in Australia," he said.

The Colong Foundation has started a campaign against the proposal. Visit for more information.​

Media Release: Don’t Raise the Warragamba Dam Wall

The Kowmung River

The Kowmung River

Coming on the heels of plans to rip up native vegetation laws in the city and the bush, conservationists are reeling from today’s announcement to raise of the Warragamba dam wall as it would damage the Greater Blue Mountains World Heritage Area.

“There would be significant and obvious damage to World Heritage listed wilderness and national parks upstream of the dam.  The lower reaches of protected wild rivers, including the Kowmung, Coxs and Nattai Rivers, would be damaged.  Flood inundation will scar wilderness areas by killing river bank vegetation and depositing sediment”, Keith Muir director of the Colong Foundation for Wilderness said, responding to the Premier, Mike Baird’s announcement of this morning.

“Even with the proposed dam wall raising the other half of Hawkesbury-Nepean’s catchment south of Sydney can produce major floods, as experienced at Picton less than two weeks ago.  Big floods from the Grose, Colo and Macdonald Rivers and the South Metropolitan Catchments will still affect residential property”, he said.

“What the Warragamba dam raising proposal will do is encourage massive urban sprawl over flood prone areas, putting more people at risk of the floods.  So the dam wall raising proposal is a half measure, one that creates a false sense of security and probably produce no net gain in public safely.  Further, urban development on previously flood prone land will further degrade the Hawkesbury-Nepean River from addition urban runoff and sewage discharges.  Oyster farmers will also be badly hit by extended fresh water floods from mitigation discharges killing off oyster farms and causing economic ruin,” Mr Muir said.

“A better solution is to use the capacity of the existing dam for flood mitigation and rely on the auxiliary spillway on the eastern side of the dam wall to carry extreme floods past the dam with safety.  This proposal will provide many of the benefits of the proposed dam wall raising for a faction of the cost.  More importantly, it respects our international obligations to protect World Heritage, something that, like climate change, appears to be of no concern to this current NSW Government,” said Mr Muir.

For more information contact: Keith Muir, (02) 9261 2400 (wk) or 0412 791 404 (mob)



Colong Foundation Media Release : Raising Warragamba Dam Wall - Expensive, Ineffective and Environmentally Destructive

Raising the wall of Warragamba Dam by 23 metres to reduce downstream flooding -- as recommended in the Hawkesbury-Nepean Valley Flood Management Review -- would lead to the destruction of some of the most heavily-protected wilderness areas in Australia, yet still fail to eliminate the flood risks for western Sydney communities. 

Media release: Raising Warragamba Dam Wall - Expensive, Ineffective and Environmentally Destructive.