Don’t Damn the Macquarie
The Dam Project – Gin Gin
At least $84 million dollars of public money would be used to build a new dam on the Wambuul-Macquarie River that would only benefit a small portion of the community.
The NSW government want to build the enormous structure to gain more control over the water in the river, and increase the volumes that can be pumped by general security customers.
The extra water that will be available for customers is water that is currently free to flow naturally down the river, through Warren to the creeks, Macquarie Marshes, Lower Macquarie and onto the Barwon Darling Rivers.
When full, the massive super weir, with 8.2 meter high gates, would back the river up for 32km – holding back 6 billion litres of water and raising the depth of the current Gin Gin weir pool by about 4.5 meters.
32km of riverbank vegetation would be drowned, including centuries old River Red Gums.
WaterNSW know that a registered Aboriginal Heritage site will be inundated by the dam. In their scoping report they say that there’s likely to be other similar sites around, as if that makes the destruction of one site OK.
Murray Lower Darling River Indigenous Nations (MLDRIN) is a peak representative body, advising the MDBA, as well as NSW agencies regarding appropriate consultation with First Nations on waterway management issues. MLDRIN has received no formal notification or been engaged by the proponent on this project. Read MLDRIN’s submission to the project’s EPBC referral here.
The internationally recognised Ramsar listed Macquarie Marshes are one of the most important sites for waterbirds in Australia. In 2010 the Australian Government issued a formal notification of a likely “change of ecological character of the Macquarie Marshes Ramsar site” to the Ramsar Secretariat. The condition of the Macquarie Marshes Ramsar site remain poor because of the ongoing effects of river regulation. This project will exacerbate ongoing decline in all of the elements outlined in the 2010 notification to Ramsar listed wetlands. Read what ecologist Professor Richard Kingsford said in his submission to the EPBC referral here.
The dam would destroy habitat, and significantly impact populations of vulnerable Murray Cod and threatened Trout Cod and Silver Perch. The impact to iconic native fish this dam would have cannot be ameliorated by a fishway. The new re-regulator will have highly varying water levels that will vary over short time scales within an irrigation season. These are likely to impact breeding of Murray cod and catfish. – read what Dr Martin Mallen-Cooper, native fish expert has to say
WaterNSW keep saying they will not catch tributary inflows from rivers like the Talbragar, Bell and Little, however their own documentation says that they will, making it difficult to trust what they say. How else can the dam produce the extra water it is promising general security irrigation customers?
The project will catch free flowing unregulated water that currently flows freely to the struggling internationally recognised Ramsar listed Macquarie Marshes and the Barwon Darling-Baaka River.
So how can WaterNSW say they won’t capture tributary flows? Well they call some tributary flows dam releases! It’s a matter of making the definition suit your purpose. Read what river ecologist Bill Johnson has to say.
The irrigation industry in the Macquarie Valley far exceeds the natural capacity of the Valley to provide water. The over-allocation of the river is a critical issue – highlighted by the fact that as of July 2020, not all of the water allocated to general security in 2016 was available to be delivered.
Water woes in the valley could be addressed by changing some key rules in the water sharing plan, like taking into account drought figures that include the years after 2004, not selling water that has not yet fallen as rain, and debiting customer’s water accounts if they order too much water.
It’s time now for the community to decide – is this the future that we want? Is the Wambuul Macquarie River more than just an irrigation water delivery channel?
Ecologists Bill Johnson, Professor Richard Kingsford and Dr Martin Mallen-Cooper.
Bill Johnson, 1st May 2020
In the Macquarie Valley, tributary flows downstream of Burrendong Dam are considered part of the regulated supply for the purpose of meeting water orders or other commitments. If the tributaries are flowing their water is used, where possible, to meet demands that would otherwise be met from the regulated supply in Burrendong Dam. Read Bill Johnson’s comments
Professor Richard Kingsford, 9th June 2020
The key elements of these objectives are delivery efficiency, reduction in transmission losses, and maximising available water for general security. This identifies that the proposed weir and re-regulating storage structure is aimed to capture unregulated flows in the Macquarie River so that they can be diverted primarily for irrigation. This water is currently not diverted for irrigation. It goes to support the riverine environment, including
downstream wetlands such as the Macquarie Marshes and its dependent organisms. The proposed re-regulating storage on the Macquarie River will reduce flows downstream to these important, nationally significant and Ramsar-listed wetlands, and will have socio economic impacts on downstream areas of the Macquarie Marshes. It will be able to redirect planned environmental water and unregulated water from the Little Bell River, the Bell River and the Talbragar Rivers – all of which are currently unregulated and exhibit flows
consistent with natural regimes – for irrigation use downstream. The quantity of flows which will be taken from the environment, as a result of this proposed structure remains unknown. Read Professor Kingsford’s submission here
Dr Martin Mallen-Cooper, 30th June 2020
The proposed Macquarie Re-regulating Structure would have a major negative impact on the river ecosystem, reducing biodiversity and reducing native fish populations. There are four major impacts….. Read Dr Mallen-Cooper’s comments here
Healthy Rivers Dubbo 