Flawed reasoningSo, why is the government embarking upon such an expensive, ineffective and environmentally destructive project? We know from recent statements by Water Utilities Minister, Don Harwin, that the NSW Government plans to open 2355 hectares of downstream floodplains to property developers. The property developers want to build sprawling new suburbs across the Hawkesbury-Nepean floodplains. This is a seriously dangerous idea.
Property developers think that raising Warragamba Dam will allow them to falsely claim that the thousands of new houses they build will be safe from flooding. Floods are a natural and unstoppable phenomenon in the valley. Raising Warragamba Dam will by no means stop floods from happening. At best, a raised dam wall would marginally reduce the height of some floods. Building houses on floodplains puts thousands of lives at risk.
In terms of managing floods in existing suburbs, flood levee construction, pre-flood release of dam waters and improved evacuation routes are all alternative options which can be implemented at less cost, while not destroying parts of one of the most protected natural landscapes in Australia. It’s simply a no brainer.
Australia’s international world heritage obligations cannot be a secondary consideration to an ill-considered dam proposal. The NSW and Australian Governments risk international embarrassment and ridicule if the dam raising proceeds. Rare eucalypt and dry rainforest communities found nowhere else in the world would die from sedimentation, erosion and weed invasion. At least 29 endangered and critically endangered native plant and animal species are found in the proposed destruction zone. A raised dam would put their very existence at risk.
Downstream environmental damage would follow the raising of the dam wall. Longer duration floods would cause river bank
erosion, resulting in a wider and shallower Hawkesbury-Nepean River. Downstream wetlands such as Bakers Lagoon depend on natural floods for nutrient replenishment. These wetlands and their associated wildlife populations would deteriorate.
Protecting cultureMany Indigenous cultural sites would also fall victim to any raise of the Warragamba Dam wall. The Burragorang Valley was home to the Gandangara people long before Warragamba Dam flooded the valley in 1960. The dam drowned large parts of their land and precious cultural sites. We do not need to repeat this story of destruction with the remaining cultural sites in the rest of the valley.