Bill Johnson, 1st May 2020
Introduction; water for irrigation, utilities and stock and domestic use
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.
A former water department regional manager in Dubbo once explained that it helped to think of a ‘notional dam near Narromine.’ From the position of maximising regulation and extractive use this makes sense. But it is a legacy of a time when other values of water were not considered.
Role of the re-regulating storage
The Macquarie River Re-regulating Storage (MRRS) Scoping Report states that;
The new re-regulating storage will improve water security, reliability and delivery efficiency in the Macquarie River valley. The re-regulating storage will be located downstream of Burrendong Dam, between the townships of Narromine and Warren (p 6).
WaterNSW and the consultants have said that the new storage will not regulate tributary flows.
The MRRS Scoping Report says otherwise. Section 2.1.1 points out that, under the current plan, some tributary flows will be regulated (my highlighting).
The proposed re-regulating storage would function as a storage that is capable of capturing surplus flow events and regulating them, as required, to reduce operational losses. The intent of the storage is to capture operational releases from Burrendong Dam that are surplus to operational need and to store them temporarily until required to supply subsequent water orders. Releases identified as surplus within approximately 6 days’ travel time from Burrendong Dam may potentially be captured.
The source of operational surplus flows released from Burrendong Dam can include the following:
- Customer orders that are subsequently cancelled due to, for example, rainfall events occurring which negate the need for irrigation
- Orders subsequently met by useful tributary contributory inflows
- Releases in excess of those required to cover delivery losses (p 16).
This section cannot be interpreted in any way other than that tributary flows will be regulated by the new storage.
My summary of the Report is;
The purpose and operation of the storage will be to capture operational releases from Burrendong Dam and store them to meet orders. These releases include tributary flows downstream of the dam.
Statements that downstream tributary flows will not be regulated by the new storage are only true because they are considered by WaterNSW to be releases from Burrendong Dam.
A reasonable person would not call tributary flows into the Macquarie, downstream of Burrendong Dam, releases from Burrendong Dam. Flows from the Talbragar, Bell and Little Rivers, Coolbaggie Creek, and other smaller streams that join the Macquarie downstream of the dam do not come from the dam.
A reasonable person would be astonished by this notion. That the notion exists, and is the published position of the NSW Government, would be met with disbelief.
Operation of the weir
The term useful tributary flows, meaning those that can be used to meet orders, demonstrates the NSW Government’s priorities. There is no stated limit to the amount of water to be regulated from the tributaries. Flows will be regarded as useful, and will be regulated, if they can be used to meet orders.
The capacity to hold these flows in the new storage means that more flows will fit the category of useful, and more water will be regulated and extracted. It allows a blank cheque for regulation and extraction of tributary flows.
It is naïve to think that WaterNSW will not use the storage to regulate as much of the tributary flows as possible. It will be managed to maximise the amount of water extracted. The more water it can control the better the narrow financial argument for it will be.
It is likely that tributary flows will be deemed useful, and available for regulation by the storage, if they can be used to;
- meet irrigation orders rather than using releases from Burrendong Dam,
- restore flows to regulated sections of the river and creeks downstream of the weir,
- provide regulated stock and domestic supplies,
- provide stock and domestic supplies from unregulated flows.
In 1987 the NSW Government published a Regional Environmental Plan for the Macquarie Marshes that said;
The Audit found the WRC [Water Resources Commission] was ineffective in management of the State’s water resources, having difficulty in moving beyond its former role of rural supply authority. Broad water needs of the whole community, including the needs of the natural environment, were residual considerations to irrigation development and operations…The new Department of Water will be required to address cultural, scientific and aesthetic values as legitimate community needs in terms of water management.
Water is mentioned in terms of losses and surplus more than 60 times in the MRSS Scoping Report. The proposal by WaterNSW to build a new storage on the Macquarie River, and the language it uses, show that the perspectives and objectives of the NSW water agencies have not changed since the 1980s.
Government failure to address the broad water needs of the whole community has long been a serious problem. Community dissatisfaction with water management in NSW was a major factor in the National Party’s loss of the seat of Barwon to the Shooters, Fishers and Farmers Party. It is a lesson that hasn’t been learnt.