I believe it is time to correct some misinformation that has been doing the rounds regarding the Yanco, Billabong and Colombo Creeks.
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The Sustainable Diversion Limit (SDL) adjustment project involves placing a regulator at the top of the Yanco Creek. This is not designed to cut off or drain the Yanco and Billabong systems.
At the top of the Yanco system there is an open cutting from the Murrumbidgee River that was originally dug in the 1800s. This cutting diverts approximately 10 per cent of the flow that is moving down the Murrumbidgee River downstream of the Yanco Weir.
The current operational plan of the Yanco Creek aims at maintaining flows under 1000 megalitres a day – this keeps the flow within the creek’s banks.
A flow rate of 1400 ML/d is an absolute maximum within the operational plan. Flows higher than this spill out into flood runners (particularly at the top of the Yanco Creek), cause minor flooding and substantially reduce delivery efficiency. The only exceptions to this are planned flooding (detailed in the above report) and natural flooding on the Murrumbidgee which would still flow down the Yanco.
An example of this occurred last year with an attempt to flood the mid-Murrumbidgee Wetlands downstream of Yanco Weir. With the operational limit at Wagga of 20,000 ML/d, a flow of 15,000 to 17,000 ML/d can be achieved at the Yanco Weir. With the cutting and no regulator, 1500 to 1700 ML/d of this flows down the Yanco. This means that the flow downstream of Yanco Weir is reduced to around 13,500 to 15,300 ML/d. This makes it harder to get water into the Mid-Murrumbidgee wetlands downstream of Yanco Weir and takes longer for those that can be reached with this lower flow.
The works proposed as part of this project allow more efficient watering of those wetlands and reduces the amount of the water needed to achieve the same environmental result – hence the SDL adjustment savings (estimated at 10 to 15 gigalitres). These savings mean less water is required in the environmental bucket, not that water is taken from production.
The concept document around this project has been released and clearly shows the intention to maintain flows for environmental and other needs in the Yanco and Billabong systems. Copies of that report are publicly available at https://www.industry.nsw.gov.au/__data/assets/pdf_file/0006/165129/Improved-Flow-Management-Works-at-the-Murrumbidgee-Rivers-Yanco-Creek-Offtake-Business-case.pdf
The relevant section on the Yanco System Ecology etc starts on page 17 of the report, in particular the sentence on page 19 that states: “This recommendation correlates to a target end of system baseflow recommendation of 50 ML/d (Jan-Apr) and 200 ML/d (May-Dec)”.
Any references to piping etc as part of the effluent streams project (separate project) refer to the small flood runners, anabranches etc not the main channel of the Yanco, Billabong, Colombo system.
I do not support draining or cutting off the Yanco, Billabong and Colombo system. I do not believe that this project is designed to drain or cut off the Yanco, Billabong and Colombo system. If anyone proposes draining or cutting off the Yanco, Billabong and Colombo system – I will fight it along with everyone else, to prevent that happening.
These are not just words. I have a track record in this area.
During my time at CICL, I championed to the board for the installation of a FlumeGate regulator at the bottom end of the Coleambally Main Canal to replace the manual gate at the escape (and I was the project manager for the installation). This escape feeds into the Coleambally Catchment Drain (CCD) which then flows into the Yanco Creek just downstream of Morundah. Installation of the remotely operated FlumeGate allowed delivery of up to 150ML/d to the Yanco within 24 hours. Delivery to this point from the offtake at Yanco Weir takes up to 3-5 days. This improved the ability to react to increases in demand along the Yanco system.
Due to the success of this installation, State Water (now WaterNSW) funded the installation of a second FlumeGate at the escape and very substantial CCD widening works to increase the capacity to 300 ML/d. As the GM Operations I advocated for this to the CICL board and oversaw the works.
The other criticism of the SDL adjustment project is the lack of consultation. That is understandable.
The process for these SDL Offset projects is a convoluted one. Until now, it has involved ensuring it is listed with the Federal Government. Whilst that is called a business case (as required in the act), in reality it is more a concept plan. Approval by the Federal Government (passed in May this year) means that it can now be considered.
The NSW Government is currently seeking funding from the Commonwealth Government to allow us to do the pre-construction activities, such as consultation, further design, environmental assessment and approvals.
The formal consultation will start as soon as that funding is provided by the Commonwealth. That is the way that this process works.
While the 198 page report contains a lot of detail, it does not mean that the project is a done deal or that the construction is due to start (it is still a long way from shovel ready). Having been involved in a number of consultations over the last decade or more, the usual criticism is that not enough information is provided – that is not the case for the upcoming consultation on this project.
I have my own ideas on ways that some of the project might be done differently. I expect these ideas, along with everyone else’s, to be considered as part of the consultation.
I hope this information addresses some of the concerns that have been raised over recent days.