Regional

water availability

report

Weekly edition

1 February 2021

1

Contents

1. Overview ...... 3

2. System risks ...... 3

3. Climatic Conditions ...... 4

4. Southern valley based operational activities ...... 6

4.1 Murray valley ...... 6

4.2 Lower Darling valley ...... 8

4.3 Murrumbidgee valley ...... 9

5. Central valley based operational activities ...... 12

5.1 Lachlan valley ...... 12

5.2 Macquarie valley ...... 14

6. Northern valley based operational activities ...... 16

6.1 Namoi valley ...... 16

6.2 Gwydir valley ...... 18

6.3 Border rivers ...... 19

6.4 Barwon-Darling River system ...... 20

7. Coastal valley based operational activities ...... 22

7.1 Bega river ...... 22

7.2 Hunter valley ...... 23

7.3 Toonumbar ...... 24

8. Rural Dam Levels ...... 25

9. More Information ...... 26

Water availability weekly report 2

1. Overview

WaterNSW manages and operates 42 and storages to deliver water for environmental, domestic, town water, stock, industrial and irrigation purposes across the state. WaterNSW storages provide supplies to all the major river systems in Western NSW, Greater , the Southern Highlands, Shoalhaven Bay as well as the Hunter, Bega, and Iron Pot valleys in coastal NSW.

The total active storage percentage of rural water supplies on 1 February 2021 was 48.2%. This was a decrease of 0.4% since last week.

The total storage level of urban water supplies on 1 February 2021 was 92.9%. This was an increase of 0.1% since last week.

2. System risks

Rainfall in previous weeks with some increases in stream flows in the Gwydir, Namoi and Castlereagh/Macquarie valleys, and the Barwon-Darling system. Cease to flow along the Darling River below Wilcannia with risks of poor water quality as flows recommence. WaterNSW is working with BOM in assessing the likelihood of filling storages, with the positive seasonal rainfall forecasts, and preparing for pre-releases and flood operations. All floodplain landholders are recommended to review their flood operations plans and be aware of any notifications from BoM and SES. Any floods and floodplain flows that occur in the coming months may also trigger poor water quality, particularly low dissolved oxygen for fish, as floodwaters may pick up significant amounts of accumulated leaf litter. Rainfall over most catchments in previous weeks has maintained stream flows and inflows to the dams. Water availability has increased in several valleys and operational plans are being reviewed as these inflows accumulate.

Water availability weekly report 3

3. Climatic Conditions

A low-pressure trough across central parts will continue to move northeast today before weakening over the far northeast later, resulting in the continuation of unsettled conditions over the east and north of the state. A southerly change will also move north along the east coast today, with a low-pressure system deepening offshore of the south coast. A high-pressure system over the Great Australian Bight will continue to extend a ridge over the west of the state with mostly sunny conditions.

For the first part of the week, most regions across the state are predicted to receive rainfall. Falls of up to 25mm should be received state-wide. As the week progresses, the rainfall will move easterly with again up to 25 mm being forecast for most regions. The western regions of the state are predicted to remain dry.

Figure 2a – First 4-day forecast (2 – 5 February 21) Figure 2b – Following 4-day forecast (6 – 9 February 21)

Water availability weekly report 4

Climate outlook overview

Issued 28 January 2021

February–April likely wetter than average • February is likely to be wetter than average along the NSW coast (greater than 60% chance). Elsewhere there is no significant shift towards a wetter or drier than average month.

• February to April is likely to be wetter than average across much of NSW, (greater than 50% chance)

•

Figure 3 – 3-month rainfall outlook

ENSO Outlook The 2020–21 LaNiña is likely to have peaked with respect to atmospheric and oceanic patterns in the tropical Pacific. However, impacts associated with La Niña, such as above average rainfall in eastern and northern Australia, are expected to persist into early autumn, indicating above average rainfall is likely for parts of these regions.

Water availability weekly report 5

4. 4Southern valley based operational activities

4.1 Murray Valley

Storage and release status

• is currently at 55 percent of active capacity and releasing about 6,200 ML/d. The release will vary to meet the regulated flow demands.

• Release downstream of Yarrawonga Weir is at approximately 8,900 ML/d and is likely to remain steady. The operational deliveries below Yarrawonga will be within channel capacity.

• The Edward River offtake flow (about 1,580 ML/d) will remain within channel capacity of 1,600 ML/d.

• The Gulpa Creek offtake flow (340 ML/d) will gradually come down to 250ML over the next few days to channel capacity.

• Stevens Weir level is at approximately 4.50 m and will vary marginally to supply environmental water to Wakool system. Currently, the water level upstream of Wakool District Main Canal Regulator is approximately 1.6 m.

• Flow downstream of Stevens Weir is approximately 2,500 ML/d to meet MDBA flow requirements to address the Barmah choke capacity constraints. The flow in the Edward River system is augmented by delivery via Edward River Escape (up to about 1,700 ML/day) of the Mulwala Canal to maintain the higher delivery targets below Stevens Weir.

• Water is also delivered via Perricoota Escape (about 70ML/day) and up to 100ML/day via Billabong Escape (Murrumbidgee system) to meet the operational demands of the MDBA.

• Flows into Colligen Creek (210 ML/d) will return to operational target flows of about 170 ML/day over the week; Wakool River (80 ML/d) and Yallakool Creek (240ML/d) will be varied to match the hydrograph required for the environmental water delivery.

• Flow in the Niemur River at Mallan School is currently at approximately 180 ML/d and will remain relatively steady over the week.

• Merran Creek flow upstream of its confluence with Wakool is approximately 95 ML/d with the flow forecast to marginally decrease over the week.

• Flow in Wakool River at Stoney Crossing is currently at approximately 685 ML/d and will remain relatively steady.

• Flow at Balranald is approximately 1,550 ML/d to meet end of system targets for February (180 ML/day) and the IVT volumes ordered by MDBA. However, the daily flow rates are forecast to gradually increase to about 3,000 ML/day by later this week.

Water availability weekly report 6

• Lake Victoria is currently holding approximately 311GL or 46 percent of active capacity. The flow to South Australia is at approximately 8,300 ML/d.

Environmental water operations

• The e-Water spring flow delivery into Wakool system is continuing, as per the hydrograph provided by the water holder.

Water availability

• The Water Allocation Statement (WAS) by the NSW Department of Planning, Industry and Environment (DPIE) (dated 1 February 2021) confirmed that in the NSW Murray Valley Local Water Utility (LWU) and Domestic and Stock (D&S) allocation are at 100 percent. High Security (HS) allocation is at 97 percent. The total allocation for 2020-21 to the general security category remains at 46 percent, with an average GS carryover of approximately 21 percent, this means the NSW Murray total GS water availability has reached approximately 67 percent of entitlement.

Drought operation measures

• The NSW Murray Regulated River water source remains at Drought Stage 1, meaning all allocated water can now be delivered under normal regulated river operations. Despite the small improvements, drought conditions persist.

Water quality

• Potential Blue Green Algae issues:

o A Red Alert is current for the lower Murray River from Mt Dispersion to Lock 9. There has been a minor shift in the algal assemblage over the past 7 days within the high alert zone with the potentially toxic species, Chrysosporum ovalisporum and Microcystis identified.

o Amber Alerts are in place at Hume Dam and Yarrawonga Weir. On the Murray River all stations between Picnic Point and Euston Weir are on Amber Alert. Also, there is an Amber alert at Lock 8.

o Along the Edward/Wakool River system Amber alerts remain current for Gulpa Creek, Mathoura, Old Morago and at Moulamein on the Edward River and at the Wakool- Barham Road station on the Wakool River.

o Levels of blue green algae in other sections of the Murray River continue to fluctuate.

o For more information, please visit the Water Quality Algae section of the WaterNSW website.

Planned supply interruptions:

• Maintenance activities are underway in the Stevens Weir gates and super structure under the Coatings Program. However, the maintenance activities are not expected to impact normal river operations or weir levels.

Water availability weekly report 7

4.2 Lower Darling valley

Storage and release status

• The system collectively holds approximately 321 GL of total volume of water (or 17 percent of active capacity), is releasing approximately 360 ML/d.

• Lake Wetherell is releasing 10 ML/day while Lake Pamamaroo releases are at 350 ML/day.

• The status of individual lakes are as follows: Lake Wetherell –26 percent, Tandure – 42 percent and Lake Pamamaroo – 91 percent, Copi Hollow – 86 percent, while Lakes Menindee and Cawndilla remain dry.

Environmental water operations

• The Water Sharing Plan minimum flows for the months of January through to March 2021 is 350 ML/d measured at Weir-32.

Water availability

• Forecast inflows from the current flows in the Darling River tributaries are expected to be about 5-10GL later in February.

• The total storage volume is below 640 GL and is not forecast to reach this trigger in the next few months. As such, the storage remains in NSW control and the resources are being managed for Lower Darling operations.

• The WAS by DPIE (dated 1 February 2021) confirmed that all high priority entitlements have received a full allocation including all LWU, D&S and HS licences, in accordance with the Water Sharing Plan. GS allocation remains at 30 percent. Carryover of approximately 48 percent is fully available.

Drought operation measures

• The Lower Darling Regulated River water source is assessed to be in Drought Stage 2.

Water quality

• An Amber Alert Level has been assessed for Lake Wetherell (Site 1, 2, 3 and 4), Green Alert Copi Hollow (Site N1094), Wilcannia (N1042), Darling River at Weir 32 (N1086), Darling River u/s of Weir 32 (Site N1171 and Daring River Pumping Station at Menindee (N1095).

• For more information visit the Water Quality Algae section of the WaterNSW website.

Planned supply interruptions:

• Nil.

Water availability weekly report 8

4.3 Murrumbidgee valley

Storage and release status

• is currently at 70 percent of active capacity, releasing approximately 450 ML/d and will vary to meet the system demands.

• is currently at 74 percent of active capacity releasing approximately 2,000 ML/d to satisfy the environmental, irrigation and IVT demands.

• The Beavers Creek offtake flow is 110 ML/d and the flows will marginally vary to meet the daily flow target of 60 ML/d at Kywong during the period from December 2020 through to April 2021.

• Berembed Weir is at full supply level (4.94 m) and will remain steady over the week.

• Bundidgerry storage is currently at approximately 4.17 m and will vary over the week to 4.00m depending on the diversions by Murrumbidgee Irrigation.

• Gogeldrie Weir is at approximately 5.98m and will remain steady over the week.

• The Tombullen storage (3.52m) has been refilled with system surplus as a result of rainfall rejection.

• Hay Weir is at approximately 7.64 m and with recent rainfall and rainfall rejection the weir pool level will increase to full supply level (8.6 m) over the next two weeks as the Hay Weir will be actively used to capture system surplus.

• The water level at Maude Weir (about 5 m) will increase to full supply level of 6 m to capture the system surplus. The weir will be actively used to reregulate system surplus.

• Currently, the Redbank Weir water level is at approximately 5.5 m. The weir will increase gradually to 5.64M to capture surplus flows due to the recent rain event and order rejection.

• Flow at Balranald is approximately 1,550 ML/d to meet end of system targets for February (180 ML/day) and the IVT volumes ordered by MDBA. However, the daily flow rates are forecast to gradually increase to about 3,000 ML/day by later this week.

• The current diversion into Yanco Creek is about 650 ML/day to meet system requirements. The flow into the Yanco arm below Tarabah Weir will stay steady at about 130 ML/d while the split into the Colombo arm will be approximately 450 ML/d to supply water to increasing irrigation orders and Forest Creek for environmental flows. Due to recent rainfall the DC800 and CCD escapes from CICL have been cut back to 0ML/d and Finley escape (MIL) to a flow rate of 100ML/d.

• The end of system target at Darlot is currently 300 ML/day, which includes about 50ML/day of planned eWater and up to 250 ML/day of operational demands by MDBA to supply the Murray system via Finely Escape.

• Due to the system surplus generated by rainfall rejection a 2-day supplementary event has been approved the DPIE-Water.

Water availability weekly report 9

Environmental water operations

• Planned Environmental Water Flow Rules are fully complied with at both Balranald and Darlot.

• Total combined environmental water orders for the current events stand at approximately 374 GL including planned eWater (discretionary component), held eWater and supplementary (Lowbidgee category). Of this about 115 GL is planned eWater.

• A significant eWater delivery of approximately 103 GL from early July 2020, via Yanga 1AS into Lowbidgee. The event is now complete.

• The second event delivered approximately 11 GL through Waugorah 1ES, commenced in the last week of July 2020 and is now extended to mid-February.

• A third event to deliver approximately 53 GL commenced end of July 2020 at the Nimmie Creek offtake. The event will continue until mid-February 2021. The event will support rookery maintenance in the Telephone Bank / Nap Nap.

• A fourth event to deliver approximately 45 GL commenced by mid-August 2020 to Lowbidgee assets via North Redbank Channel. This event finished in early January 2021.

• A fifth event to deliver approximately 12 GL commenced by late August 2020 at the Warriston Weir in the Forest Creek. The event is likely to be extended to second week of February 2021. The event supports the rookery in the Wanganella Swamp.

• A sixth event to deliver 119 GL is being delivered to North and South Caira channels since the end of August 2020. The delivery is planned to continue to mid-February 2021. The event will fill Loorica, Kieta, Kia lakes and to maintain bittern / rookery in the Eulimbah-Suicide- Websters swamp.

• A seventh event to deliver 30 GL of held eWater under The Living Murray (TLM) was delivered at Balranald Weir to enable fish connectivity with Murray River between 9 November and 19 November 2020.

Water availability

• For the Inter Valley Transfer (IVT) account from Murray to Murrumbidgee, please refer to the Murrumbidgee IVT Account Status section of WaterNSW website.

• The WAS by DPIE (dated 15 January 2021) confirmed that all high priority entitlements have received full opening allocations as per the Valley’s Water Sharing Plan. This includes all LWU, and D&S licences. HS licences received a further 5 percent and has now reached full 100 percent allocation for the water year. Similarly, GS licence holders have received an increase in allocation of 23 percent taking the total allocation to 100 percent. Conveyance entitlements have received commensurate full allocations as per the Water Sharing Plan.

Drought operation measures

• The Murrumbidgee Regulated River Water Source is at Drought Stage 1, meaning all allocated water can now be delivered under normal regulated river operations.

Water availability weekly report 10

Water quality

• Potential Blue Green Algae issues:

o Burrinjuck Dam at Goodhope is on red alert level, while Station One (Dam Wall), Burrinjuck Water State Park, and Woolgarlo are at Amber alert level.

o Blowering Dam Station 1 (Dam wall) and Blowering Downstream are at Green Alert Level.

o Hay Weir and Maude Weir buoys are on green alert level, while Murrumbidgee river at Redbank Weir Buoy and Balranald Weir are on amber alert level.

o Lake Wyangan North in Griffith has a Red status, while Lake Wyangan south has an amber alert for blue green algae

o Lake albert at Wagga Wagga has an amber alert level.

o For more information, please visit the Water Quality Algae section of the WaterNSW website.

Unplanned supply interruptions:

• Nil

Planned supply interruptions:

• The painting program for Gogeldrie started on 30 June 2020 and will continue until mid- February 2021. However, the maintenance activity under the coating program is not expected to impact normal River Operations and weir levels.

• High Level Offtake at the Burrinjuck Dam is unavailable due to potential trash rack failure with flow-induced vibrations. The repair works will be undertaken only when the Burrinjuck Water levels are low enough. The maximum release capacity through fixed outlet from the dam is partially reduced until the remedial works are completed. However, with the availability of other low-level valves, power stations and Stoney sluice, the system supply is expected to be fully met under normal river operations.

• Due to a planned inspection of the hollow het valves at the Blowering Dam on 2nd and 3rd February 2021, the maximum release from the Blowering Dam during the period would be limited to 3,000 ML/day. However, this will not impact the system supplies as the rest of the irrigation/environmental demand will be met from Burrinjuck Dam.

Water availability weekly report 11

5. Central valley based operational activities

5.1 Lachlan valley

Storage and release status

• is currently at 29.2 percent of capacity and is releasing approximately 2 ML/d.

• is currently at 58.5 percent of capacity and is releasing approximately 500 ML/d to meet system demand.

• Lake Cargelligo is currently at approximately 61.4 percent of capacity and will remain steady for the rest of the week.

• Releases downstream of the Brewster Weir are around 350 ML/d. Releases are forecast to remain between 400 – 500 ML/d during the week.

• Good tributary inflows this year has allowed the S&D replenishment flows to be delivered into Willandra Ck (stopped on 24 September 2020), Merrowie Ck (stopped on 26 September 2020), Merrimajeel and Muggabah ceased on 6 October 2020.

• Lake Brewster storage on 28th January 2021 was 5.12 percent of capacity with a volume of approximately 7,450 ML.

• Recent rain had produced good tributary inflows in the Belubula system resulting in access to supplementary and uncontrolled flow access.

Environmental water operations

• Tributary flows in Belubula are continuing. End of system flow condition is met by flow provided by tributaries.

• Translucent period in Lachlan ended on 15 November 2020.

• Approximately 5.5 GL of the Lachlan Water Quality Allowance will be utilised to provide a flow of 100 ML/day at Booligal Weir during January 2021 to March 2021 to reduce the risk of low dissolved oxygen for fish.

Water Availability

• WAS published by DPIE on 13th January 2021 for Lachlan, confirmed no additional allocation of GS licence holders, the total allocation this year remains 38 percent.

• In Belubula, access to uncontrolled flow event was announced below Needles on 1st Feb 2021and will cease on the 3 February 2021at 9am.

• The WAS published by DPIE on 21 October 2020 for Belubula confirmed that there is no change to allocations in the Belubula regulated river water source.

• In Belubula, GS water access licence holders have zero percent allocation but will have access to account water that has been carried over from the previous Water Year (2019- 20).

Water availability weekly report 12

• Water operations update for Belubula can be found at the Belubula operations section of the WaterNSW website.

• Water Quality

• The Wyangala Storage results (14 January 2021) show continuing low productivity at all sites. Detections of Dolichospermum circinale were observed at Station 1. The storage is now on Green Alert Level.

• The Carcoar Storage latest samples (6 January 2021) continue to show low productivity with no cyanobacteria detected in the upstream sample. Downstream also showed no cyanobacteria detected. Storage remains at Amber Alert Level.

• The Lake Brewster Sample results from the 8 January 20221 showed high productivity across the system. Lake Brewster Outlet Channel is now on Red alert.

• Results from Lake Cargelligo on 6 January 2021 show slightly increasing productivity across the storage. Green and flood alga dominate the assemblage at all sites however Dolichospermum sp. is now present at the Curlew waters and downstream in the Lachlan. Few other cyanobacteria were detected. System is now on amber alert.

Planned supply interruptions:

• Nil

Water availability weekly report 13

5.2 Macquarie valley

Storage and release status

• is at 39.7 percent of active capacity and currently releasing approximately 1,400 ML/d. Releases are expected to be between 1,000- 1,200 ML/d this week. Currently all releases made from the dam are to satisfy irrigation demand.

• Windamere Dam is currently at 29 percent of active capacity and releasing 70 ML/d. Releases are forecast to remain steady at about 50 - 70 ML/d during this week.

• Rainfall and inflows this year have delayed indefinitely the second phase of the transfer from Windamere to Burrendong. The transfer will leave a minimum of 70 GL in Windamere Dam, which provides a very secure supply for local demand for the next five to seven years.

Environmental Water operations

• Environmental watering event at Marebone will finish on 4th Feb 2021.

• The translucent flow period in Macquarie ended on 30 November 2020.

• Translucent environmental water from Windamere Dam is deliverable all through the year when inflows to the Dam meet the relevant triggers, subject to storage volume being more than 110 GL. Windamere storage volume reached 110GL on 13 Nov 2020 but has now fallen below that trigger level.

Water availability

• The WAS published by DPIE on 15 January 2021confirmed that an additional allocation of 5 percent has been made to GS licence holders, bringing the total allocation this year to 28 percent.

• LWU, S&D licences and HS allocations have 100 percent entitlement.

• All HS licence categories received 100 percent allocation on 1July 2020.

• Trade from the Cudgegong Valley down to the Macquarie water source can resume in accordance with the Water Sharing Plan.

• Given that GS water users have been prevented from accessing their water during the drought, protection from account reductions due to evaporation or spills from Burrendong Dam will be provided until the end of February 2021.

• Burrendong Dam gained approximately 35,000 ML in the month of January 2021.

• Carryover evaporation reduction in Macquarie and Cudgegong has been applied on carryover balances of General Security and High Security accounts at the end of the second quarter of the 2020-21 Water Year.

• A 3 percent carryover evaporation reduction was applied to Macquarie River and 1 percent to .

Water availability weekly report 14

Drought operation measures

• Due to recent rainfall and inflows into the dam and downstream of the dam, the Macquarie Regulated River Water Source has improved to Drought Stage 1.

• All S&D replenishments were completed in 2019-20 water year.

Water quality

• Burrendong Dam: Results for the 29 December show low productivity near the Dam Wall but productivity increases up into the arms. Few cyanobacteria were noted at most sites however Dolichospermum sp. is prevalent in the Mookerawa arm. The Cudgegong arm shows elevated productivity but few cyanobacteria. Storage is now at Green alert.

• Windamere dam: Results for 5 January 2021 show that productivity has remained high across the storage. The assemblage has shifted to Microcystis sp. Downstream results showed no cyanobacteria present. Windamere Dam is now on Red alert.

• The cold-water pollution curtain at Burrendong is damaged and the curtain is not in operation. WaterNSW is assessing the damage.

Planned supply interruptions: N/A

Water availability weekly report 15

6. Northern valley based operational activities

6.1 Namoi valley

Storage, release and inflow status

• is at 12.62 percent of active capacity (down from 12.69 percent a week ago), and releases are 30ML/d. Releases are forecast to increase to 50 ML/d during the week.

• is at 43.76 percent of active capacity, down from 44.77 percent a week ago, and is currently releasing about 1,000 ML/d. Releases are forecast to remain around 1,000 ML/d during the week and then to decrease to less than 800 ML/d at the end of the week.

• is at 42.00 percent of active capacity, up from 41.93 percent a week ago, and is currently releasing 3 ML/d.

• The Pian Creek replenishment flow has been completed from flows below Keepit Dam.

• For regular updates, refer to the Operations Update section of WaterNSW website.

Environmental water operations

• There are no current orders for the release of environmental water in the Namoi Valley.

• Planned environmental releases of 3 ML/d from Chaffey Dam continue as the dam has risen above the 20 percent trigger in the Chaffey pipeline authorisation.

Water availability

• Uncontrolled flow access was allowed in Peel Valley due to recent rainfall event.

• The Water Allocation Statement, published by DPIE (dated 14 January 2021) confirmed that in the Peel Valley both Local water utility (LWU) and Domestic and Stock (D&S) allocations have received another increase by 10 percent of entitlement resulting in a total 100 percent; HS and its sub-categories' allocations have received another increase by 50 percent of entitlement resulting in a total 100 percent

• Peel General Security (GS) allocation has received an increase by 16% resulting in 16% allocation for the current water year. Environmental Contingency Allowance (ECA) account also increases by the same percentage.

• The latest Water Allocation Statement, published by DPIE (dated 13 January 2021) confirmed resource improvements high enough to warrant increase in allocations both in the Upper Namoi Valley and in the Lower Namoi Valley: the GS allocation the Upper Namoi Valley have increased by 50% of entitlement, for a cumulative allocation of 100 per cent for the current water year. The GS allocation the Lower Namoi Valley have increased by 23.7% of entitlement, for a cumulative allocation of 31.7 per cent for the current water year.

Water availability weekly report 16

• All other categories of licence in the Upper and Lower Namoi Regulated River Water Source remain unchanged.

Drought operation measures

• The Peel Valley is in Drought Stage 1. Commissioning of the Chaffey to Dungowan pipeline is complete and operation of the pipeline commenced on 17 June 2020 and have now ceased as the dam is above 20 percent. Operational flow targets below Chaffey will be for water-on-order and release will increase when needed.

• The Upper Namoi Valley is at Drought Stage 1. Releases will be used to supply water orders in the Manilla River from Split Rock Dam to the junction with the Namoi River. For customers located on the Namoi River (below Manilla), water orders will be supplied (where possible) using the inflows from the Namoi Unregulated River. Customers wishing to take water from their HS, GS or S&D licences are reminded to place an order for their water.

• The Lower Namoi is at Drought Stage 1 under the Incident Response Guide.

• The Lower Namoi Operations updates.

Water quality

• Split Rock Dam is on an Amber Alert Level in the storage.

• Keepit Dam is on a Green Alert Level in the storage; and

• Chaffey Dam is on an Amber Alert Level in the storage.

Planned supply interruptions:

• Mollee Fishway is currently unavailable due to infrastructure failure.

Water availability weekly report 17

6.2 Gwydir valley

Storage, release and inflow status

• is at 19.16 percent of active capacity (down from 19.63 percent last week). Copeton Dam is currently releasing about 1,060 ML/d; releases are likely to decrease during the week.

• Block releases started on 26 November 2020 and releases have varied as tributary inflows have contributed to meeting demands. Releases are being reassessed - please see the Gwydir Valley Update

Environmental water operations

• Environmental flow orders are continuing in parts of the system.

• Planned environmental “3 Tributary’ water continues to be delivered as per water sharing plan rules.

Water availability

• The latest Water Allocation Statement published by DPIE -Water (dated 15 January 2021) confirmed that general security allocation in the Gwydir received an increase of 7.11 percent of entitlement resulting in 12.18 percent of general security entitlement for the 2020- 21 Water Year. Environmental Contingency Allowance (ECA) account also increases by the same percentage.

• Approximately 5 percent of the GS has been carried over the 2020-21 Water Year.

• LWU licence holders and D&S access licence holders have 100 percent entitlement and HS licence holders have 100 percent.

• Supplementary access was allowed in Gwydir Valley due to recent rainfall event. Refer to

• supplementary announcement page in WaterNSW website for details

Water quality

• Recent Blue Green Algae (BGA) sampling at Copeton shows Copeton on an Amber Alert Level in the storage.

Drought operation measures

• The Gwydir Valley is in Drought Stage 1. Management action will focus on ensuring water is available for critical needs for as long as possible.

Planned supply interruptions

• No supply interruptions are expected.

Water availability weekly report 18

6.3 Border Rivers

Storage, release and inflow status

• is at 11.8 percent of capacity. Currently releasing around 50ML/day as translucent flow.

• Glenlyon Dam is at 13.9 percent of capacity and releases have ceased.

• Boggabilla Weir is currently full from tributary inflows and passing all inflows.

• For regular updates, please refer to the Operations Update section of WaterNSW website.

Environmental Water operations

• Stimulus flow release from Pindari Dam started on 1 October 2020 and around 4,500 ML was released throughout October 2020. Please visit the Operational Update section of the WaterNSW website for more details.

• Translucent flow release of about 50 ML/d from Pindari Dam has commenced again after the completion of the block release.

• Around 2.9 GL of environmental water has been delivered at Mungindi. That water started arriving at Mungindi on 4 January.

Water availability

• The latest WAS, published by DPIE -Water (dated 18 November 2020) confirmed 41.3 percent allocation for General Security A in the NSW Border Rivers regulated water source that totals 64.6 percent. No allocation to General Security B is possible until A receives a full (100 percent) allocation, in accordance with the Water Sharing Plan.

• There are no temporary water restrictions, but low storage levels mean deliverability of account water is challenging and depends on drought operational measures and tributary inflows.

• All licence categories, except GS, have received full allocations.

• Block release from Pindari Dam commenced on 17 December 2020 and completed on 3 January 2021.

Drought operation measures

• The Border Rivers are in Drought Stage 2.

Water quality

• Recent Blue Green Algae (BGA) sampling at Pindari shows a red alert level.

Planned supply interruptions:

• Pindari dam low level valve maintenance work has been completed.

Water availability weekly report 19

6.4 Barwon-Darling River system

River flow status

• River system is currently flowing from Mungindi to Wilcannia. Flow first arrived from Thalaba Creek upstream of Walgett on 26 December 2020 and further inflow arrived later from Namoi, Moonie, Border, Gwydir and Culgoa. Local rainfall also contributed to this event.

• A significant part of Border and Gwydir inflow is active environmental water.

• While inflows from Border, Namoi and Gwydir is continuing at lower rates, additional inflow has arrived from the Castlereagh and Moonie Rivers.

• Water reached Wilcannia on 30 January. Based on current forecast, around 13 - 20 GL expected at Wilcannia. Around 5 -10 GL is forecast to reach Lake Wetherell from this event.

Environmental water operations

• Environmental water delivery is currently in progress. Around 2.9 GL at Mungindi from the Border Rivers and 5.1GL at Galloway from Gwydir system was ordered. Most of that water is now in the Barwon-Darling system.

• Environmental licence holders have also elected to ‘protect’ their share of access and this Active Environmental Water (AEW) is being actively managed down the river system.

• Planned Environmental Water (PEW) is water in the system that is below the Commence to Pump conditions for access licences. From 9am 12th January 2021 to 24 January, access was not available in all Management Zones because of the activation of the Resumption of Flow rule which was relaxed on 9am 24 January.

• Barwon Darling full Active Management has commenced. The flow class announcements indicate the amount of Active Environmental Water at each location.

Water Availability

• The latest WAS, published by DPIE -Water (dated 1 July 2020) confirmed 100 percent allocation for all licence classes in the Barwon Darling Unregulated River water source.

• According to the amended WAS, published 1 July 2020, flow class announcements will be made every day when the flow class availability is A class or above. Please refer to the Water Insights Portal for recent flow class announcements.

• From 9am 12th January 2021, access was not available in all Management Zones because of the activation of the Resumption of Flow rule.

• The Resumption of Flow rule is further relaxed from 9:00AM 29 January 2021 and currently normal access is available for all management zones. The relaxation of the Resumption of Flow rule is based on the current forecast exceeding the flow requirements under the Water Sharing Plan.

Water availability weekly report 20

Drought operation measures

• The Barwon Darling unregulated river water source is assessed to be in Drought Stage 2.

Water availability weekly report 21

WaterNSW HYPLOT V134 Output 02/02/2021 Period 8 Month 01/07/2020 to 01/03/2021 2020-21 416001 BARWON R @ MUNGINDI 141.008 Hour Mean Discharge (ML/d) CP 6000 5000 4000 3000 2000 1000 0 416050 BARWON U/S PRESBURY 141.008 Hour Mean Discharge (ML/d) CP 6000 5000 4000 3000 2000 1000 0 422004 BARWON @ MOGIL MOGIL 141.008 Hour Mean Discharge (ML/d) CP 6000 5000 4000 3000 2000 1000 0 422003 BARWON @COLLARENEBRI 141.008 Hour Mean Discharge (ML/d) CP 6000 5000 4000 3000 2000 1000 0 422025 BARWON @ TARA 141.008 Hour Mean Discharge (ML/d) CP 6000 5000 4000 3000 2000 1000 0 422001 BARWON @ DANGAR BDGE 141.008 Hour Mean Discharge (ML/d) CP 6000 5000 4000 3000 2000 1000 0 422026 BARWON @ BOOROOMA 141.008 Hour Mean Discharge (ML/d) CP 6000 5000 4000 3000 2000 1000 0 422027 BARWON @ GEERA 141.008 Hour Mean Discharge (ML/d) CP 6000 5000 4000 3000 2000 1000 0 Jul Aug Sep Oct Nov Dec Jan Feb

WaterNSW HYPLOT V134 Output 02/02/2021 Period 8 Month 01/07/2020 to 01/03/2021 2020-21 422002 BARWON @ BREWARRINA 141.00 8 Hour Mean Discharge (ML/d) CP 6000 5000 4000 3000 2000 1000 0 422028 BARWON @ BEEMERY 141.00 8 Hour Mean Discharge (ML/d) CP 6000 5000 4000 3000 2000 1000 0 425039 DARLING@WARRAWEENA 141.00 8 Hour Mean Discharge (ML/d) CP 6000 5000 4000 3000 2000 1000 0 425003 DARLING@BOURKE TOWN 141.00 8 Hour Mean Discharge (ML/d) CP 6000 5000 4000 3000 2000 1000 0 425004 DARLING@LOUTH 141.00 8 Hour Mean Discharge (ML/d) CP 6000 5000 4000 3000 2000 1000 0 425900 DARLING@TILPA 141.00 8 Hour Mean Discharge (ML/d) CP 6000 5000 4000 3000 2000 1000 0 425008 DARLING@WILC. MAIN C 141.00 8 Hour Mean Discharge (ML/d) CP 6000 5000 4000 3000 2000 1000 0 Jul Aug Sep Oct Nov Dec Jan Feb

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7. Coastal valley based operational activities

7.1 Bega river

Storage and release status

• is at 101 percent of capacity and spilling.

Environmental water operations

• There are no current additional operations.

Water availability

• An AWD of 40 percent for GS, and 100 percent for all other licence categories was announced on 1 July 2020.

• Access to Supplementary in all sections of Bega Brogo river has now ceased. Access to Uncontrolled flows is available in all river sections until further notice.

Drought operation measures

• The Bega/Brogo Regulated River water source is assessed to be in normal conditions now, improved from Drought Stage 4 to normal conditions.

• WaterNSW held an online River Operations Stakeholder Consultation Committee (ROSCCo) meeting on 9 September 2020 and provided the operational updates to the group.

Water quality

• Recent sampling (3 November 2020) continue to show very low productivity across the storage. No cyanobacteria were observed upstream. The assemblage is dominated by small counts of diatoms. Downstream showed a minor cyanobacterial detection. Storage remains on green alert.

Planned supply interruptions

• Nil.

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7.2 Hunter valley

Storage and release status

• is currently at 50 percent of capacity. Releases from the dam were ceased due to recent rain and increase in tributary inflows.

• is at 44 percent of capacity and releases were restarted with 20ML/d as tributary flows have receded.

• is at 101 percent of capacity and spilling.

Environmental Water operations

• Currently, all environmental flow targets are being met.

Water availability

• Supplementary and uncontrolled flow access in all sections has ceased except Zone 2B.

• The recent WAS published by DPIE on 19 January 2021 confirms that a 13 percent increase in allocation has been made to GS licences.

• The new allocation has increased total GS AWD to 75 percent this year. Carryover is equivalent to approximately 23 percent of the total share component. HS and all other categories received 100 percent allocation.

• The EWA has been credited with 20 GL in accordance with the Water Sharing Plan.

• Paterson Valley allocations are at 100 percent for all licence categories.

Drought operation measures

• The Hunter Regulated River water source is assessed to be at Drought Stage 1 normal operations.

Water quality

• Recent samples (17 November 2020) at Glenbawn shows that Microcystis sp. is still present at all upstream sites however overall productivity has declined. Downstream results showed no cyanobacteria present. Storage is now at Green Alert Level.

• Recent sampling results (26 November 2020) at Glennies Creek Dam show that productivity is increasing again across the storage. Assemblage is mixed with small counts of cyanobacteria, flood and green alga present. No cyanobacteria were detected downstream. Storage is now at Green Alert Level.

• Recent BGA results for Lostock dam shows the upstream assemblage is dominated by flood alga. No cyanobacteria were observed. Downstream results showed a minor Microcystis sp. detection. Storage remains at Green Alert Level.

• Planned supply interruptions:

• Nil

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7.3

Storage and release status

• Toonumbar Dam is at 100 percent of capacity and spilling.

• The previous dam spill was in March 2018.

Environmental water operations

• No current additional operations.

Water availability

• All licence categories have 100 percent availability.

• WaterNSW held an online ROSCCo meeting on 14 October 2020 and advised the stakeholders present of the current situation and future operations plan.

• Full allocations already announced for all entitlement holders in the 2020-21 Water Year.

Drought operation measures

• The Drought Stage level has eased from Drought Stage 2 to normal operations.

Water quality

• Sample results for Toonumbar Dam (17/11) shows that productivity has increased across the storage. Minor counts of Microcystis sp. were noted however the assemblage is dominated by benign cyanobacteria. A similar assemblage of cyanobacteria was observed downstream. The storage is now on amber alert.

Planned supply interruptions:

• Scheduled works for replacement of the 610” valve have been postponed, until further notice.

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8. Rural Dam Levels

The following table shows the status of water supplies at 1 February 2021.

Weekly Likeliho Active River Valley Current Status change Comments od of fill Allocations for 2020/21 Capacity (GL) and spill

percent of Weekly C’over Active High Gen. Storage Dam, Nearest Town (GL) active Change Supply Issues avail @ (GL) Security Security capacity (GL) 1/7/20

Border Rivers Glenlyon Dam, Stanthorpe 253 14% 35 -0 Release ceased <20% 100% 5.4% 2% (Qld)

Pindari Dam, Inverell 312 12% 37 -0 Translucent flow release <20% 100% 5.4% 2%

Gwydir Valley Copeton Dam, Inverell 1346 19% 258 -6 Regulated releases <5% 100% 12.18% 5% Namoi Valley Keepit Dam, Gunnedah 419 44% 183 -5 Regulated releases <20% 100% 31.7% 6% Split Rock Dam, Manilla 394 13% 50 -0 Regulated releases <5% 100% 100% N/A Chaffey Dam, Tamworth 101 42% 42 -0 Min release & d/s tribs <50% 100% 16% N/A

Macquarie Valley

Irrigation water release. Env Burrendong Dam, Wellington 1154 40% 459 -12 <10% 100% 28% 16% releases complete

Windamere Dam, 367 29% 106 -1 Regulated releases <5% 100% 28% 58%

Lachlan Valley Wyangala Dam, Cowra 1217 59% 712 -13 Regulated releases <10% 100% 38% 6%

D/s trib flows increase, Supp Carcoar Dam, Carcoar 36 29% 10 -0 <10% 100% 0% 28% and UCF access

Murrumbidgee Valley Regulated releases Burrinjuck Dam, Yass 1025 70% 713 -21 <25% 100% 100% N/A including eWater and IVT Regulated releases Blowering Dam, Tumut 1604 74% 1183 -2 <10% 100% 100% N/A including eWater and IVT Murray Dartmouth, Mitta Mitta (Vic) 3837 61% 2333 10 Minimum releases N/A N/A N/A N/A Regulated releases Hume Dam, Albury 2982 54% 1622 -8 <25% 97% 46% 21% including eWater Lower Darling

Menindee Lakes, Broken Hill 1633 18% 283 -5 Min regulated releases <30% 100% 30% 48%

Hunter Valley Reduced Regulated Glenbawn Dam, Scone 750 50% 373 -0 release, Supp access in <10% 100% 75% 23% lower sections Glennies Ck Dam, Singleton 282 44% 123 1 Regulated release <20% 100% 75% 23% Lostock Dam, Gresford 20 101% 20 0 Spill 100% 100% 100% N/A Coastal Area

Toonumbar Dam, Kyogle 11 100% 11 -0 Spill 100% 100% 100% N/A

Spilling, access to Supp Brogo Dam, Bega 9 101% 9 0 ceased and access to UCF 100% 100% 40% N/A continues until further notice

Total 17749 48.2% 8560 -63 WaterNSW has water resources in Dartmouth, Hume and Glenlyon Dams. TWS = Town Water Supplies 1 Gigalitre (GL) = 1,000 Megalitres (ML) 1 ML = 1,000,000 litres

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9. More Information

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