The proposal to raise the height of Warragamba Dam by 23 metres is unnecessary and environmentally damaging. The existing dam and auxiliary spillway provides the necessary dam safety. Installing new flood gates and improved flood monitoring would provide substantial flood mitigation at a saving of more than $500 million.
Some of the amount saved could be used for comprehensive flood management, including voluntary purchase and/or re-location of low lying houses and other structures; removing them from the path of all floods, not just smaller floods as is the case with the 23 metre raising.
There will be no protection against large floods (one in 500 average, and higher) even if the dam is enlarged.
Take Action - write to Premier Mike Baird (and check out the fact sheets below).
There would be significant and obvious damage of World Heritage 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.
The false sense of security created by raising the dam wall will encourage the further release of low lying land on which development is currently prohibited. As many as 100,000 houses could be constructed with the following detrimental effects:
- Up to a million additional vehicle movements per day in the Hawkesbury-Nepean valley, causing traffic congestion, air pollution and resulting health problems in the whole of western Sydney;
- A huge increase in run-off and sewage discharge that will cause even worse deterioration of water quality in the Hawkesbury-Nepean River;
- Loss of rich agricultural land to urban expansion and destruction of fisheries, including the major oyster farming industry.
Don't raise the dam fact sheets -