Temporary Water Restriction - Northern NSW Murray Darling Basin Amendment

Reason for Decision

Temporary Water Restriction (Northern NSW Murray Darling Basin) Order 2020

Overview

A temporary water restriction applied to Northern Basin catchments from 17 January to 31 January to protect inflows arising from rainfall runoff for critical needs. This restriction has been extended until 17 February 2020.

Rainfall in the northern NSW Murray Darling Basin over January resulted in only short, sharp inflows into most river systems that received runoff, with no persistent flows. The exception being the Peel Regulated River Water Source where access was permitted for high security users and the Mooki River and Quirindi Creek water sources where access was permitted for unregulated river access users from 26 to 31 January 2020.

The Bureau of Meteorology has forecast further rain for February and this is likely to occur as localised storm events.

Protection of inflows resulting from this follow-up rain is necessary for the public interest, due to the ongoing severe drought conditions. It ensures local critical needs (town water, domestic and stock, basic landholder rights, and critical drought refuge areas) are met from inflow events and will improve the likelihood of flows from this and subsequent events reaching the Lower Darling.

Recent rain has also assisted in providing improved soil moisture across many of the northern valleys but has not provided connectivity of the river or addressed critical human needs in these valleys. However, many of the systems are now primed, and with the continuing forecast of storm events with increased moisture from the northern tropics, the section 324 order has been extended. This will protect flows that may occur to achieve connectivity along the northern rivers to ensure critical human needs are met, and that water holes along the river are filled.

Under the extended restriction, river pumping is not permitted by the licence holders listed in Table 1. This will allow replenishment of town water supplies, supply to high priority users, re-filling of instream refuge pools in the local catchment, and potentially flow into the Barwon-Darling and Lower Darling systems.

The temporary restriction does not apply to the take of water by regulated river general security access licence holders if, prior to the commencement of the temporary restrictions, the water has been ordered and released from a dam by WaterNSW.

The restriction has been amended so that restrictions do not apply in the Campbells River Downstream Management Zone, the Macquarie River above Bathurst Management Zone, the Fish River Water Source – downstream of Lake Oberon to confluence with Macquarie River, and the Macquarie River between Bathurst and Evans Plains Creek Management Zone, which are all Macquarie Bogan Unregulated Water Sources. All but Macquarie River between Bathurst and Evans Plains Creek Management Zone are subject to an existing temporary water restriction which is already protecting Bathurst’s town water supply. Irrigators in the Macquarie River between Bathurst and Evans Plains Creek Management Zone are reliant on excess water passing through Bathurst and sewage treatment plant discharge. As there are currently no natural inflows, a restriction would prohibit access to water that they would have otherwise be able to legally extract.

The temporary restriction does not apply to the take of water for testing metering equipment, and does not apply to the take of water from farm dams.

The restriction will be in effect until Monday, 17 February 2020. The restriction can be repealed or amended prior to this date, should conditions change.

The order provides for responsive management. That is, should a substantial natural unregulated flow event occur, and that flows are in excess of that required for critical needs in the northern tributaries or downstream river systems, the Department can approve the take of water by access licence holders. Rainfall and inflows will be closely monitored during this period to determine if a repeal, amendment or advice to customers allowing access is needed.

Table 1. Water sources and licence categories to which the restriction applies.
Water SourceLicences
Barwon-Darling Unregulated River Water Source Unregulated river (A, B and C Classes) access licences
Intersecting Streams Unregulated Water Sources Unregulated river access licence and unregulated river (special additional high flow) access licence
NSW Border Rivers Unregulated Water Sources Unregulated river access licences and unregulated river (special additional high flow) access licence
Namoi Unregulated Rivers Water Sources Unregulated river access licences and unregulated river (special additional high flow) access licence
Peel Unregulated River Water Sources Unregulated river access licences
Castlereagh River Unregulated Water Sources Unregulated river access licences and unregulated river (special additional high flow) access licence
Macquarie Bogan Unregulated Water Sources, with the exception of Campbells River Downstream Management Zone, Macquarie River above Bathurst Management Zone, Fish River Water Source – downstream of Lake Oberon to confluence with Macquarie River, Macquarie River between Bathurst and Evans Plains Creek Management Zone Unregulated river access licences and unregulated river (special additional high flow) access licence
Gwydir Unregulated River Water Sources Unregulated river access licence and unregulated river (special additional high flow) access licence
Peel Regulated River Water Source Regulated river (high security) access licence (unless water is ordered and released from a dam by WaterNSW)
NSW Border Rivers Regulated Water SourcesNSW Border Rivers Regulated Water Sources Regulated river (high security), regulated river (general security), regulated river (general security A and B class) access licences (unless water is ordered and released from a dam by WaterNSW)
Gwydir Regulated Water Source Regulated river (general security) access licences (unless water is ordered and released from a dam by Water NSW)
Upper and Lower Namoi Regulated River Water Source Regulated River (high security) access licences (unless water is ordered and released from a dam by Water NSW)

Background

In times of extreme drought, protecting water supply for critical needs is a key priority. All northern regulated valleys, and both the Barwon-Darling and Lower Darling, are in Stage 3 severe or Stage 4 critical drought. Inflows into the Barwon-Darling River and the major northern storages are at record low levels, despite recent rainfall events.

Having a temporary restriction order on irrigator access allows any moderate flows to be protected for critical needs.

Town water supplies remain at low levels across much of the north-west and far west of NSW.   Many towns such as Walgett and Mungindi could potentially be out of river water in the next few months if no or only low inflows occur into the major storages. Towns downstream of Tilpa (Wilcannia and Menindee) did not receive inflows from the November 2019 rain event. It is essential that all inflows are protected for these higher priority critical town supply needs.

The overarching aim of the restriction is to ensure that critical needs (town water supply, basic landholder rights, high security and environmental needs) are met if there are inflows following the extended dry period – both in local river valleys, and if possible downstream in the Barwon-Darling and the Lower Darling. Placing a temporary water restriction order on access to natural, unregulated flows by unregulated licence holders and general and high security licence holders is a way to achieve this aim.

Reasons for Decisions

Temporary water restriction – section 324

Section 324 of the Water Management Act 2000 allows the Minister or delegate to order that temporary water restrictions within a water source are to have effect for a specified period, if satisfied that these restrictions are necessary to do so in the public interest.

There is a public interest in making an order to prohibit take in accordance with the temporary water restriction order as follows:

  • “To cope with a water shortage” - Remaining water supplies in the north-western catchments are at very low levels. The north-western regulated river systems, the Barwon Darling and the Lower Darling are at Stage 3 (severe) or Stage 4 (critical) water shortage under the NSW Extreme Events Policy, and flows must be protected for critical human needs. Replenishment flows to many systems have not occurred for some time for domestic and stock purposes and water is being carted to many areas.
  • “Threat to public health and safety” - Town water supplies are reaching low levels across much of the north-west and far west of NSW. Many towns could potentially be out of river water in the next few months if there are no low inflows to storages. Similarly many creek systems in these valleys have not had full replenishment flows to meet domestic and stock needs, and water is being carted for these purposes. It is essential that all inflows are protected for these higher priority critical needs.
  • Manage water for environmental purposes” - Low flow conditions persist across most of the northern NSW Murray-Darling Basin. As the drought continues and the river system becomes increasingly disconnected, pools that provide critical refuge for aquatic biota are drying up water. The quality in remaining pools is declining, putting native fish (and other aquatic biota) at risk.

Prior to local rain in 2019 and the 2019 northern fish flow event, the Barwon-Darling River had not flowed since August 2018. There are still sections of the river that have not flowed since then.

Critical wetlands and habitats across the northern basin are heavily impacted by the current drought. Only limited releases are being made below Warren in the Macquarie River from the January inflows.

In the Gwydir and Mehi rivers, downstream inflows have provided riparian flows to limited river sections and assisted in recent environmental deliveries reaching the end of system in the Carole/Gil Gil and Gwydir systems. Inflows were insufficient to provide water for all river sections, with the Moomin Creek and Mehi River below Bronte unlikely to receive any flow.

Due to the ongoing drought conditions some inflows had high turbidity which may settle out in water holes as flows cease. Whilst no significant fish deaths or other water quality issues have been identified in the Gwydir Valley at this time, as flows cease and rivers dry back the potential for water quality impacts to occur is expected to increase throughout the remainder of summer and until conditions begin to cool.

If there are sufficient flows, the temporary water restriction will replenish pools in the inland northern rivers that provide refuge for fish and other aquatic species, contribute to connectivity, and improve water quality. Protecting any upstream flows should they occur will also enhance the prospects of water reaching Menindee, and potentially connect refuge pools and supply critical environmental needs in the Lower Darling.

Vanessa O'Keefe

A/ Executive Director, Water Policy, Planning and Sciences

30 January 2020