Regional

water availability

report

Weekly edition 13 July 2020

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 ...... 9

5.1 Lachlan valley ...... 13

5.2 Macquarie valley ...... 15

6. Northern valley based operational activities ...... 18

6.1 Namoi valley ...... 18

6.2 Gwydir valley ...... 20

6.3 Border rivers ...... 21

6.4 Barwon-Darling River system ...... 21

7. Coastal valley based operational activities ...... 27

7.1 Bega river ...... 27

7.2 Hunter valley ...... 28

7.3 Toonumbar ...... 29

8. Rural Dam Levels ...... 30

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 13 July 2020 was 36.2% of the total active storage capacity. This was an increase of 0.5% since last week.

*Note - Total volumes were reported for the previously which is now changed to active volume.

The total storage level of urban water supplies on 13 July 2020 was 80.4% of the total storage capacity. A decrease of 0.2% since last week.

2. System risks

The relatively small inflows to most northern dams mean that drought measures and works are being reviewed, but most will likely remain in place, despite the larger flows downstream. This is particularly the case for Chaffey, Split Rock and Wyangala Dams, where the risks to critical needs remains high. Risks are also increasing in the Hunter Valley as inflows to Glenbawn and Glennies Ck Dams continue to track well below previous drought records.

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3. Climatic Conditions

Figure 1 - Weekly rainfall totals for New South Wales

This week’s weather forecast

A low-pressure system over the Tasman Sea is deepening. This system will whip up blustery winds and powerful waves along parts of the New South Wales coast today. Winds are expected to gradually ease on Wednesday, and the waves on Thursday, as the low moves east towards New Zealand and a high-pressure ridge moves over the state from the west.

For the first part of the week, coastal regions of the state are forecast to receive up to 25mm of rainfall with the rest of the state predicted to remain dry. As the week progresses, majority of the state is predicted to remain dry with negligible rainfall only being seen along the coastal fringes.

Figure 2a – First 4-day Forecast (14 – 17 July 2020) Figure 2b – Following 4-day forecast (18 - 21 July 2020)

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Climate outlook overview

Issued 9 July

A wetter fortnight likely for New South Wales and a wetter 3 months likely for most of NSW

• NSW have increased chances of a wetter than average fortnight, greater than 70% chance.

• The August to October and September to November outlooks indicates that most of NSW is likely to see a wetter than average spring.

Figure 3 – 3-month rainfall outlook

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4. 4Southern valley based operational activities

4.1 Murray Valley

Storage and release status

• is currently 43% of active capacity, and at minimum releases of 600ML/d.

• Release downstream of Yarrawonga Weir is at about 8,200 ML/day and is likely to increase further above channel capacity, with forest regulators open to assist to manage the channel capacity constraint.

• Recent rainfall has led to modest streamflow rises in the Kiewa, Ovens and Goulburn catchments, which has helped extend the duration and volume of unregulated flows in the River Murray System. DPIE-Water extended the period of unregulated flow for certain reaches of the River Murray System that started on the 27 June 2020 to 21 July 2020.

• The Edward River Offtake flow is currently about 1,700 ML/d, which is above the regulated channel capacity. The increase has been necessary to manage the channel capacity at Picnic Point. The flow would be gradually returned to about 1,600ML/day over the week.

• The Gulpa Creek Offtake flow is at about 300ML/d and likely to vary up to 350ML/day over the week.

• Stevens Weir level is about 4.36 m and is likely to be gradually lowered to about 3.9m subject to prevalence of uncontrolled flow conditions. Water level upstream of Wakool Canal offtake is about 1.0 m.

• Flow downstream of Stevens Weir is about 600 ML/day and is forecast to vary between 500 and 600 ML/day due to supplementary access in the Murray system.

• Flows in the Colligen Creek (280 ML/day), Yallakool Creek (250ML/day), and Wakool offtake (20 ML/d) are likely to marginally vary to manage the supplementary access demands in the system.

• Flow in Niemur River at Mallan School is currently about 104ML/d and the flow will gradually increase to about 160ML/day over the next week.

• Merran Creek flows upstream of its confluence with Wakool is about 111ML/day and the flow will gradually increase to about 130ML/day over the next week.

• Flow in Wakool River at Stoney Crossing is currently at about 295 ML/day and is likely to increase gradually to about 430 ML/day over the week with the arrival of uncontrolled flows.

• Flow at Balranald is currently about 2,140 ML/d and will increase with uncontrolled flows over the week. The end of system target at Balranald for the month of July is 829ML/day.

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• Lake Victoria is currently holding about 630 GL or 92% of active capacity. The lake is effectively full under the Lake Victoria operating strategy that maintains airspace in the lake while there are unregulated flow conditions. The flow to South Australia is about 13,300 ML/d.

Environmental water operations

• eWater delivery has now ceased into Wakool-Yallakool system and into Colligen-Niemur system.

Water availability

• The Water Allocation Statement by DPIE (dated 15th July 2020) confirmed that in the NSW Murray Valley local water utility, and domestic & stock allocation is 100%; high security 97%, Regulated river (conveyance) category 51%, and general security is 2% with carryover equivalent to 21% of total general security share components. The allocations for all temporary critical conveyance licences are also 100%.

Drought operation measures

• The NSW Murray regulated river water source remains at Stage 2, meaning drought operational planning has commenced in preparation for extreme dry conditions that may continue through 2020-21.

Water quality

• Potential Blue Green Algae issues:

– Recent Blue Green Algae (BGA) sampling at Lake Hume shows Lake Hume is on a Green alert level. The sites at Heywoods and Ebden indicate Amber alert level.

– For more information visit: Water Quality Algae

Planned supply interruptions:

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

Water availability weekly report 7

4.2 Lower Darling valley

Storage and release status

• Menindee Lakes system collectively holds about 27% of active capacity, and is releasing about 220 ML/d.

• The status of individual lakes: Lake Wetherell - 68%, Tandure – 85%, and Lake Pamamaroo – 120%, Copi Hollow – 135%; while Lakes Menindee and Cawndilla remain dry.

• As per the Water Sharing Plan, the planned minimum flows for the months of May to October will target 200 ML/day measured at Weir-32.

• Total inflows to the lakes measured at Wilcannia that commenced on 10 March 2020 is about 667 GL.

Water availability

• To date the current inflows have not resulted in the total storage volume reaching 640GL and are currently not forecast to reach this trigger in the next few months. As such the storage remains in NSW control and the resources shall be managed for Lower Darling operations.

• The Water Allocation Statement by DPIE (dated 15th July 2020) confirmed that all high priority entitlements have received a full allocation including all local water utility, domestic, stock and high security licences, in accordance with the water sharing plan. General security entitlements have received an opening allocation of 30%. Carryover of about 48% is fully available.

Drought operation measures

• The Lower Darling regulated river water source is assessed to be in drought Stage 2.

Water quality

• Green alert for Lake Wetherell (site 1, 2, 3 and 4), 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 @ Menindee (N1095).

– For more information visit: Water Quality Algae.

Planned supply interruptions:

None

Water availability weekly report 8

4.3 Murrumbidgee valley

Storage and release status

• is currently at 44% of active capacity, releasing about 450 ML/d. The release is likely to vary in line with system demands especially when releases from the is stopped for maintenance activities.

• Blowering Dam is currently at 59% of active capacity, releasing about 560 ML/d. The release is likely to remain steady as per transparent release rules. However, there will be a two-day outage on 21-22 July when there will be no water release from the dam. See planned outage section below for details.

• With the rainfall over the last week of June, DPI&E has announced a one-day supplementary event. The event will be announced for different reaches of the river as the flow travels downstream. The alerts to the customers for the event as it opens for different reaches are sent via email and SMS. Customers may contact the WaterNSW Call Centre (1300 662 077) to register for receiving the alerts by email or SMS, if they have not already done so.

• The Beavers Creek offtake regulator is fully open as per the work approval conditions. Decreasing flows at Wagga Wagga (2,230 ML/day) are likely to further decrease in the Beavers Creek at Mundowey (11 ML/d) over the week.

• Berembed Weir (1.3 m) had been fully lowered for annual maintenance and the gates had been withdrawn from water last week. The scheduled maintenance is nearing completion and the weir is expected to be reinstated this week. This will result in the water levels upstream of the weir to gradually rise at about 300mm per day over the next two weeks.

• Bundidgerry storage is currently at about 4.2 m and is likely to gradually reduce as per MI water diversions and/or system losses. The storage will be replenished only by late July when the water level at Berembed Weir is sufficient to divert water into the Main Canal offtake.

• The annual maintenance work at Golgeldrie weir is now complete and the weir has been reinstated. Gogeldrie Weir is currently being filled at a rate of about 300 mm/d. The weir is expected to return to normal service levels by 24-July.

• Tombullen storage level is about 2.18m. Water from the storage will be released to meet downstream water demands over the next two weeks. The release rates will vary between 300 and 800 ML/day depending on the system demands. The storage is expected to be empty by the end of July. Capture and re-regulation of any future system surplus in the Tombullen storage is subject to the availability of the infrastructure managed by Coleambally Irrigation Corporation, especially the top section of their main canal.

• Hay Weir is currently being lowered for routine winter maintenance at a rate of 250 to 300mm/d. By mid-July the level is expected to below 5.5m impacting the town water supply pumps. The gates will be withdrawn clear of water by 24th July for annual essential maintenance.

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• Maude Weir is at 3.5 m that is the optimum weir height to keep the Nimmie-Caira offtake channels drier for maintenance works in the Nimmie Creek Regulator until 22-July.

• Currently, the Redbank Weir level is about 5.69 m. The level is to remain relatively steady for the next few weeks while environmental water is being delivered to Lowbidgee.

• Flow at Balranald is currently about 2,140 ML/d and will increase with uncontrolled flows over the week. The end of system target at Balranald for the month of July is 829ML/day.

• The current diversion into Yanco Creek is about 240 ML/d and is likely to remain relatively steady over the week. The flow into the Yanco arm below Tarabah Weir will be maintained at about 80 ML/day, while the split into Colombo arm will be about 140 to 160 ML/day.

Environmental water operations

• Planned environmental releases as per the transparency rules is being delivered from Blowering and transparent/translucent releases from Burrinjuck Dam.

• The Burrinjuck Dam translucent rules operate between 22 April and 21 October. These rules mean that a proportion of daily inflows are released, which means releases can be large when inflows are higher.

• Planned environmental water flow rules are fully complied with at both Balranald and Darlot.

• A significant eWater delivery of about 34,000ML (planned environmental water) over a period of about 6-weeks was started on 6th July via Yanga 1AS into Lowbidgee. In addition, about 5,000ML of planned environmental water will be delivered to Nimmie Creek system starting last week of July.

Water availability

• For Inter Valley Transfer (IVT) account from Murray to Murrumbidgee refer to WaterNSW website WaterNSW website

• The Water Allocation Statement by DPIE (dated 15th July 2020) confirmed that all high priority entitlements have received full opening allocations as per the valley’s water sharing plan. This includes all local water utility, domestic, stock and high security licences. General security users have received an increase in allocation of 4% taking the total allocation to-date to 14%. Carryover is fully available, estimated to be about 340 GL or 18% of general security entitlement on average. Conveyance entitlements have received full opening 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. Despite the small improvements, drought conditions continue to threaten.

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Water quality

• Potential Blue Green Algae issues:

– Burrinjuck Dam at Station 1 (Dam Wall), Downstream, Burrinjuck Water State Park, Woogarlo and Goodhope are at Green alert level.

– Blowering Dam on a Green alert status.

– For more information visit: Water Quality Algae.

Unplanned supply interruptions:

• Nil

Planned supply interruptions:

• Regular winter maintenance at Berembed Weir and the MI main canal offtake regulator is nearing completion. The weir is expected to be returned to normal service level by end of July 2020.

• Regular winter maintenance work at Gogeldrie Weir is now complete. Raising the weir pool has started on the 6th July 2020. The weir is expected to return to normal service levels by 24th July.

• Planning is underway to commence regular winter maintenance of Hay Weir. In preparation of the planned maintenance, the Hay Weir is being gradually lowered. Gates are expected to be clear of water by 24th July 2020. The weir is expected to be returned to normal service levels (about 6.0 m) by mid-August 2020.

• Maude weir will be maintained below a level of 3.7m in order to keep the Nimmie creek regulator work area from being inundated until 22nd July.

• As part of the coating program, the Nimmie Creek offtake gates will be removed for a period of 5-weeks starting on the 3rd June 2020. Supply to North Caira, South Caira and Nimmie Creeks are impacted. Due to wet-weather and resultant track issues there has been a minor delay in the schedule and as per the revised dates, the Nimmie Creek regulator is expected to be returned to service by 22nd July 2020. However, water delivery through any of these structures are reliant on sufficient head being available in the Maude Weir, which is expected to be by end of July 2020.

• Painting of super-structure of the Maude Weir has started and will be completed by 30th October 2020. Painting programme for Gogeldrie started on the 30th June and will continue until mid-January 2021. However, the maintenance activity under the coating program is not expected to impact the normal river operations and Weir levels.

• Planning is underway to carryout required works on the Emergency Coaster Gate in the Blowering intake tower. The closure will result in little or no flows in the Tumut River for about 48 to 72 hours during 21-22 July and again on 4-6 August 2020. However, the flow in the Murrumbidgee

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River will not be impacted as any tributary flow would be augmented by additional releases from Burrinjuck Dam to meet irrigation and environmental demands.

• Planned maintenance work in the High-Level outlets and one of the four low level outlets have commenced. The works are expected to be complete by end of July 2020. Due to the maintenance activities, the maximum release capacity from Burrinjuck Dam is expected to be about 6,000 ML/day during the planned outage period. The projected release capacity is forecast to be sufficient to meet the system demand during this time of the year.

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5. Central valley based operational activities

5.1 Lachlan valley

Storage and release status

• is currently 16.8% of capacity and releasing 2ML/d.

• is currently 17.1% of capacity and releasing around 60ML/d. Releases are forecast to remain at 60-80M/d for rest of the week.

• Maintenance works have been completed on Jemalong Weir gates, the level is currently 4m and will continue to rise to around 5.8m within the next two weeks.

• Lake Cargelligo is currently around 87.1% of capacity and will reduce slowly over the next two weeks to 70%, this will allow for the construction of seepage monitoring devices. Once works have finished the lake will be used to capture any tributary inflows downstream of Wyangala.

• Releases downstream of Brewster Weir are around 90ML/d. Releases are forecast to remain around 60-90ML/d during the week.

• Willandra Ck flow ceased from 1st December 2019 and releases may resume with any increase in tributary inflows.

• The recent rain and tributary flows d/s of dam have produced some surplus flows. The flows are being diverted into Lake Brewster outflow wetlands and into the main cell from Lake Brewster weir. The water coming from Lake Cargelligo storage due to maintenance works will also be captured in Brewster. The current Lake Brewster storage volume is 29% of capacity with a volume of 42,500ML.

Environmental water operations

• Due to drought conditions, end of system daily environmental flow requirements in the Belubula River have been suspended and are only being met intermittently with the contribution from tributaries.

Water Availability

• It is estimated that a combined dam and tributary inflow volume of more than 273GL was required in June before a further allocation could be made in the Lachlan River. Inflows received in June were just under 4GL.

• The DPIE Water Allocation Statement (WAS) published on 1 July 2020 water availability for 2020- 21 water year.

• Full (100%) allocation for all Local Water Utilities and Domestic & Stock license holders • 70% allocation for High Security license holders.

• Conveyance will receive its commensurate allocation in accordance with the water sharing plan.

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• No allocation to General Security. • In addition, access to water in general security accounts on 1 July 2020 will be restricted to 50% of the active sub-account balance on 30 June 2020.

Inflows needed to improve deliverability of carryover

2019-20 inflow period Inflows (GL) 1 July Additional combined Additional inflows 2019 to 30 April 2020 inflows required to deliver required for new GS remaining usable allocations in 2020-21, AWD (GL) begin to ease GS delivery restrictions and to start (no restrictions) increasing HS allocation

By end of June 177 95 273

By end of July 177 100

By end of Aug 177 168

Notes: Estimated water held in general security accounts on 1 July 2019 was 155,000 ML. Water delivery operations in 2019-20 provided under drought contingency planning (Stage 3). Minimum storage level of 5% is targeted at the end of 2019-20 water year to maintain critical supplies in 2020- 21.

• These are indicative improvements only and are not guaranteed. Estimates may change based on weather variability, water management decisions and other events. This means water users should use this information with caution and at their own risk, as it projects many months ahead.

• The assessment for the table above is based on water delivery operations in 2019-20 provided under drought stage 3 and 2020-21 under severe drought stage 4. NSW extreme events policy can be viewed at Extreme Events Policy.

• In the Belubula, general security water access licence holders have 0% allocation but will have access to account water that has been carried over from the previous water year. A Temporary Water Restriction under Section 324 of the Water Management Act 2000 has been gazetted on 1 October 2019. It allows access to 40% of the water in general security access licence account balance as at 30 September 2019. The remaining 60 per cent is moved to a drought subaccount and cannot be used. Please refer: Belubula WAS Oct 2019

• While allocations for the Belubula River system have been announced by DPIE Water, the delivery of water is restricted due to the ongoing drought. Please refer: Belubula Ops Update Oct 2019 • At the Belubula Landholders Association meeting on 21 January 2020 the following were agreed,

• Water delivery between Carcoar Dam and Needles is maintained to meet daily demand until end of February or early March 2020.

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• High security and domestic and stock access licence holders on regulated Belubula receive 100% allocation.

• The Department of Planning, Industry & Environment – Water has now approved access to uncontrolled flows in the Belubula River during the recent trib flow events.

Water Quality

• Latest BGA samples show that Lake Cargelligo Boatshed, Lake Cargelligo TWS, Lake Cargelligo Outlet, Lake Cargelligo intake d/s of Curlew Water are on a Green Alert.

• Wyangala Storage results (25th June) show that productivity has declined at all sites. Few cyanobacteria across the entirety of the storage have been noted except for a moderate Dolichospermum sp. detection at the Lachlan Abercrombie confluence. Downstream showed low level detections of benign cyanobacteria. The storage is now on amber alert.

• Some flow is being circulated through the Lake Cargelligo inlet and outlet with the intention of improving water quality in the channels connecting the lakes and the river.

Planned supply interruptions:

Jemalong Weir maintenance

• WaterNSW has scheduled planned maintenance and repair work on Jemalong Weir.

• Scheduled work at Jemalong Weir have commenced on 29th June and finished on the 9th of July. During this period, the weir gates will be fully raised, and a good flow will be still maintained past the weir resulting from the tributaries, this will meet the downstream requirements.

Wyangala Dam maintenance

• There will be an outage at Wyangala Dam starting the first week of June ending third week of July. This outage will require all releases to be through the bypass line and the maximum dam release capacity during the outage is about 300 ML/d. The forecast demand in the upper Lachlan above lake Cargelligo is unlikely to be more than the release capacity of the bypass line.

Water availability weekly report 15

5.2 Macquarie valley

Storage and release status

• is at 24.1% of active capacity and currently releasing around 30ML/d. Releases are forecast to remain steady this week. Downstream tributary flows continue to meet town water supply and Domestic and Stock demands. Storage inflows in June were around 21GL.

• is currently 27.1% of active capacity (100GL) and releasing 13ML/d. Releases are forecast to stay around 10- 20 ML/d during this week.

• The recent storms and isolated stream flows have delayed the second phase of the transfer from Windamere to Burrendong to at least March 2021. The transfer will leave a minimum of 70GL in Windamere Dam, which provides a very secure supply for local demand for the next five to seven years.

Environmental water operations

• 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 110GL.

• Environmental water in both active and translucent accounts is available.

Water availability

• The DPIE Water Allocation Statement (WAS) published 1 July 20.

• Local Water Utility (LWU), Stock & Domestic (SD) licences and High Security allocations have 100 per cent of entitlement.

• The temporary water restriction on Macquarie general security water accounts is being amended to allow the transfer of 40 per cent of the drought sub-account balance to the active account for use.

• All higher security licence categories receive100% allocation on 1July 2020.

• Trade from the Cudgegong down to the Macquarie water source can resume in accordance within the water sharing plan.

• Given that general security 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.

Drought operation measures

• Due to recent rainfall and inflows into the dam and downstream of dam, Macquarie Regulated River Water Source has improved to Stage 3 drought Criticality

• All S&D replenishments were completed from the recent rainfall events and contributions from downstream tributaries.

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• The actual inflows to Burrendong Dam since the last AWD in August 2017 totalled about 330 GL to end of May 2020. This was just 60% of the previous record low inflow for the 34 months ending in May.

• This drier than historical minimum inflow confirms that the system has entered into a new drought of record for Burrendong Dam.

Water quality

• Burrendong Dam results for the 17th June show few cyanobacteria at all upstream sites. A minor detection of Microcystis sp. was noted at the Dam Wall and small counts of benign cyanobacteria were detected both in the Mookerawa arm and downstream. The Cudgegong arm showed no cyanobacteria. Storage remains at green alert.

• Windamere dam results for 29/06 show the assemblage continues to be dominated by Microcystis sp. at all upstream sites. Latest results however show that numbers have declined near the Dam Wall but remain elevated mid-lake. No other cyanobacteria were observed mid- lake however a detection of Dolichospermum sp. was also noted near the Dam Wall. Downstream showed a minor Microcystis sp. detection. Windamere Dam remains on amber alert.

• Works to reinstate the temperature curtain at Burrendong Dam have been completed and the commissioning phase has commenced. The curtain is fully lowered due to low storage levels.

Planned supply interruptions:

• Nil

Water availability weekly report 17

6. Northern valley based operational activities

6.1 Namoi valley

Storage, release and inflow status

• is at 4.6 % of active capacity, is currently releasing 2ML/d.

• is at 15.2% of active capacity, releases have ceased after recommencing briefly for limited domestic and stock near the dam.

• is at 15.3% of active capacity and currently releasing around 11ML/d .

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

• For regular updates, refer to the Operations Update page in WaterNSW website.

Environmental water operations

• There are not any current orders for the release of environmental water in the Namoi.

Water availability

• The Water Allocation Statement by DPIE (dated 1st July 2020) confirmed that in the Peel Valley local water utility and domestic and stock allocation is 70%; high security and its sub categories is 50%, and general security is 0%.

• There is a shortfall of more than 34.19 GL before there is likely to be an AWD increment in the Lower Namoi valley.

• The latest Water Allocation Statement by DPIE (dated 1st July 2020) confirmed the allocations in the Upper Namoi: local water utility and D&S have 100%, while high security has received 90% allocation and the general security a 0% allocation. About 39% of the general security has been carried over into 2020/21 water year. The restrictions on access to carryover have been repealed.

• Lower Namoi local water utility and D&S have 100%, high security has 90% and general security has 0%. The restrictions on access to carryover have been repealed and this volume is equivalent to about 6%.

Drought operation measures

• The Peel valley is in drought stage 4. Commissioning of the Chaffey to Dungowan pipeline is complete and operation of the pipeline commenced on 17 June. Operational flow targets below Chaffey will be for very low environmental flows.

• The Upper Namoi is now at Stage 2, down from stage 3. Releases recommenced on 30 March and 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 (were possible) using the inflows from the Namoi Unregulated River. Customers

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wishing to take water from their high security, general security or stock and domestic licences are reminded to place an order for their water

• The Lower Namoi is at Stage 3, down from the Stage 4, the highest level under the Incident Response Guide.

• Deliverability of this water will rely on tributary flows and/or improved storage volumes. No further block releases are planned for the Lower Namoi until further inflows occur.

Water quality

• Split Rock Dam is on a Green alert in the storage,

• Keepit Dam is on a Green alert in the storage, and

• Chaffey Dam is on a Green alert in the storage.

Planned supply interruptions:

• Mollee fish way is currently unavailable due to infrastructure failure.

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6.2 Gwydir valley

Storage, release and inflow status

• is at 13.5% of active capacity and is currently releasing 28ML/d.

Environmental water operations

• No current environmental flow orders.

Water availability

• The latest Water Allocation Statement by DPIE -Water (dated 1st July 2020) confirmed 0 per cent allocation for General Security (GS) water users in the Gwydir regulated river water source. About 5% of the general security has been carried over into 2020/21 water year.

• The local water utility and domestic and stock access licence holders have 100% of entitlement. High security has 100% and general security have access to about 5% carried over from the previous water year.

Water quality

• Recent Blue Green Algae (BGA) sampling at Copeton shows Copeton on a Red alert in the storage.

Drought operation measures

• The Gwydir is in drought Stage 2. Management action will focus on ensuring water is available for critical needs for as long as possible.

• However, deliverability will rely on downstream tributary contributions and infrequent block releases. Operations Update Gwydir 1-July

Planned supply interruptions:

No supply interruptions are expected.

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6.3 Border rivers

Storage, release and inflow status

• is at 12.8% of capacity and releasing around 13ML/d (minimum release).

• Glenlyon Dam is at 13.4% of capacity. Releases ceased.

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

• Flow arrived Mungindi weir pool on 15 Feb and continues to spill.

• Continued rainfall since February had generated significant flows across the Northern valleys. Catchment is wet now and response from further rainfall will be quicker.

• For regular updates, refer to the Operations Update page in WaterNSW website.

Environmental water operations

• No current additional releases for environmental water orders.

Water availability

• The latest Water Allocation Statement by DPIE -Water (dated 1st July 2020) confirmed 7.3% per cent allocation for General Security A class water users in the NSW Border Rivers regulated water source. No allocation to General Security B class is possible until A class receives a full (100%) 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 general security, have received full allocations.

Drought operation measures

• The Border Rivers is in drought Stage 3. Customers are advised that if dry conditions persist, future deliveries, including essential supplies, will be grouped together (block releases), and where possible with tributary flows, to improve delivery efficiencies.

Water quality

• Recent Blue Green Algae (BGA) sampling at Pindari shows an amber alert level.

Planned supply interruptions:

• No supply interruptions are currently forecast

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6.4 Barwon-Darling River system

River flow status

• Significant rainfall observed across northern valleys since January 2020.

• Inflows arrived from the Border, Moonie, Gwydir, Namoi, Culgoa, Bokhara, Castlereagh, Bogan and Warrego systems.

• The Barwon-Darling is now flowing from Mungindi to Wilcannia. Flow arrived at Lake Wetherell on 10 March.

• The Temporary Water Restriction Order for A, B and C class licences was removed for Mungindi to upstream of Culgoa junction section on 27 February. Temporary Water Restriction removed from downstream of Culgoa junction to upstream of Lake Wetherell section on 6 March 2020.

https://www.industry.nsw.gov.au/water/allocations-availability/temporary-water-restrictions

Environmental water operations

• Planned Environmental Water (PEW) is water in the system that is below the commence to pump conditions for access licences.

Water Availability

• The latest Water Allocation Statement by DPIE -Water (dated 1st July 2020) confirmed 100% per cent allocation for all licence classes in Barwon Darling unregulated river water source.

• Flow has resumed between Mungindi and Wilcannia and access is allowed, as per licence conditions, for customers for all management zones.

• According to amended Water Sharing Plan, from 1 July 2020, flow class announcements will be made every day when the flow class availability is A class or above. Refer to the WaterInsights Portal for recent flow class announcements.

Drought operation measures

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

Flow forecast

• The Barwon-Darling system is an unregulated river, which travels through a very arid environment with significant losses from the system due to high evaporation and long travel times. It is very difficult to accurately forecast downstream flows as local conditions can vary significantly over the number of weeks it takes the water to travel along the river.

• The below summaries are the current forecast estimates of flows along the system. This information is regularly updated as required.

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• Menindee inflow forecast is now for 587,500ML to 590,000ML.

• Small increase in forecast inflows from Border Rivers due to rainfall.

• No significant changes in forecast inflows from the Moonie, Namoi and Gwydir Rivers.

• Small inflow may arrive from Bogan river.

• The Condamine Balonne has contributed around 177 GL from Culgoa River upstream of Warraweena and around 32 GL from Bokhara River upstream of Beemery.

• Around 45GL inflow was observed at Dick’s Dam as inflow from the Warrego River, including flows from local rain that commenced on 6 March. Additional Warrego flows also arrived at Louth from flows that bypass Dick’s Dam.

• Forecasts include estimated extractions from Mungindi to Culgoa junction from 27 Feb 2020 and downstream of Culgoa junction from 6 Mar 2020.

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Location Observed Total forecast Date of flow Comments about inflows to each volume volume – arrival section (ML) including observed (ML)

Mungindi 83,709 85,000 – 86,000 15 Feb 2020 Inflows are from the Border Rivers

Presbury 73,072 74,500-75,500 5 Feb 2020

Mogil Mogil 213,697 215,000-216,000 27 Jan 2020 Expected total inflows (observed and forecast) are 17-18 GL from Gil Gil and about 76 GL from Moonie. Gain from localised inflows.

Collarenberi 252,217 253,500 – 255,000 6 Feb 2020 Expected total inflows (observed (total flow and forecast) are 25 GL from Mehi.

including Old Total observed flows at Garwon Pockataroo (Old Pockataroo) are 10 GL anabranch)

Tara 272,733 274,500 – 276,000 7 Feb 2020 Gain from localised inflows

Walgett 377,691 378,000 –379,000 9 Feb 2020 Expected total inflows (observed and forecast) are about 92.5 GL from Namoi at Goangra

Boorooma 415,423 415,600 – 417,000 13 Feb 2020 Flows were out of bank

Geera 529,972 530,000 - 531,000 12 Feb 2020 Significant inflow from Castlereagh River and Marthaguy Ck from April rainfall

Brewarrina 496,276 496,300 – 496,800 16 Feb 2020

Beemery 635,116 635,200 – 635,500 18 Feb 2020 Around 32 GL inflow arrived from Bokhara. Gain from localised inflows.

Warraweena 773,473 773,500 – 774,000 19 Feb 2020 Around 176.6GL* inflow from Culgoa.

Bourke 719,838 719,900 – 720,500 20 Feb 2020

Louth 715,257 715,270 – 715,400 24 Feb 2020 Around 45 GL* inflow from Warrego

Tilpa 682,525 682,700 – 683,200 28 Feb 2020

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Wilcannia 671,043 671,500 – 672,500 5 Mar 2020

Lake Wetherell, 587,154 587,500 - 590,000 10 Mar 2020 Around 10-20 GL expected from Lake Tandure Dolo-Bonley Creek system and Lake downstream of Wilcannia. Higher Pamamaroo losses between Wilcannia and Lake Wetherell.

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WaterNSW HYPLOT V134 Output 14/07/2020 Period 7 Month 01/01/2020 to 01/08/2020 2020 416001 BARWON R @ MUNGINDI 141.008 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 416050 BARWON U/S PRESBURY 141.008 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 422004 BARWON @ MOGIL MOGIL 141.008 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 422003 BARWON @COLLARENEBRI 141.008 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 422025 BARWON @ TARA 141.008 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 422001 BARWON @ DANGAR BDGE 141.008 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 422026 BARWON @ BOOROOMA 141.008 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 422027 BARWON @ GEERA 141.008 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 Jan Feb Mar Apr May Jun Jul

WaterNSW HYPLOT V134 Output 14/07/2020 Period 7 Month 01/01/2020 to 01/08/2020 2020 422002 BARW ON @ BREW ARRINA 141.00 8 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 422028 BARWON @ BEEMERY 141.00 8 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 425039 DARLING@W ARRAW EENA 141.00 8 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 425003 DARLING@BOURKE TOW N 141.00 8 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 425004 DARLING@LOUTH 141.00 8 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 425900 DARLING@TILPA 141.00 8 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 425008 DARLING@WILC. MAIN C 141.00 8 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 Jan Feb Mar Apr May Jun Jul

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7. Coastal valley based operational activities

7.1 Bega river

Storage and release status

• Brogo Dam is at 92.3% of capacity.

Environmental water operations

• No current additional operations.

Water availability

• An AWD of 40% for general security, and 100% for all other licence categories was announced on 1 July 20.

Drought operation measures

• The Bega/Brogo regulated river water source is assessed to be in normal conditions now, improved from drought Stage 4 to Stage 1.

• WaterNSW held an online ROSCCo meeting on 7th May 20 and provided the operational update to the group.

Water quality

• Recent BGA sampling at Brogo (23/06) showed very low productivity across the storage. No cyanobacteria were observed either upstream or downstream. The assemblage is dominated by green alga. Storage remains on green alert. Planned supply interruptions:

• Nil

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7.2 Hunter valley

Storage and release status

• is currently at 39% of capacity and releasing around 22ML/d. Releases are forecast to remain at this minimum.

• is at 37% of capacity and releases are currently around 20ML/d. Releases are forecast to remain steady during the week after rainfall events contributed to instream flows and reduced demand.

• is at 100% of capacity and spilling.

Environmental water operations

• An Environmental Water Allowance (EWA) flow event in Hunter commenced on 5th June 2020 and finished on 30 June. A total of up to 10,000 ML was delivered over and above the extractive water orders.

Water availability

• General Security licenses in the Hunter Valley received 30% allocation on the 1 July 2020 and carryover is equivalent to about 23% of total share component. High Security received a 90% allocation with carryover equivalent to 19% of share component. All other categories received 100%.

• The Environmental Water Allowance will be credited with 20 gigalitres (GL) in accordance with the water sharing plan.

• Paterson valley allocations are 100% for all licence categories.

Drought operation measures

• The Hunter regulated river water source is assessed to be at drought Stage 1, however if conditions remain dry the drought stage may escalate to stage 2 or higher.

Water quality

• Recent BGA sampling at Hunter storages indicates a green alert is maintained at Glennies Creek, however an amber alert is for Glenbawn and Lostock.

Planned supply interruptions:

• Nil

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7.3

Storage and release status

• Toonumbar Dam is at 67% of capacity and releasing about 5ML/d. A small inflow is coming into the dam from recent rainfall. This should maintain the storage volume.

Environmental water operations

• No current additional operations.

Water availability

• All licence categories have 100% availability.

• WaterNSW held a River Operations Stakeholder Consultation Committee (ROSCCo) online on 24th June 2020 and advised the stakeholders of the current situation and future operations Plan.

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

Drought operation measures

• The drought criticality level has eased from Stage 2 to Stage 1 – normal operations.

Water quality

• Recent results for Toonumbar shows that benign cyanobacteria dominate the assemblage with minor counts of Microcystis sp. noted. No cyanobacteria were detected downstream. Storage remains at amber alert awaiting another clear result

Planned supply interruptions:

• Scheduled works to commence on 5 Aug 20 and continue for 2 weeks for replacement of 610” valve have been cancelled, until further notice.

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8. Rural Dam Levels

The following table shows the status of water supplies at 13 July 2020.

Likely- Weekly hood of River Valley Capacity Current Status change Comments Allocations for 2020/21 fill and (GL) spill

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

Border Rivers

Glenlyon Dam, Stanthorpe (Qld) 253 13% 34 0 d/s trib flows continue <20% 100% 0.6% 2%

Pindari Dam, Inverell 312 13% 40 0 d/s trib flows continue <20% 100% 0.6% 2% Gwydir Valley Copeton Dam, Inverell 1346 13% 181 1 d/s trib flows continue <5% 100% 0% 5% Namoi Valley Keepit Dam, Gunnedah 419 15% 64 1 d/s trib flows continue <20% 100% 0% 6% Split Rock Dam, Manilla 394 5% 18 -0 d/s trib flows continue <5% 100% 0% 39% Chaffey Dam, Tamworth 98 15% 15 0 d/s trib flows continue <50% 50% 0% N/A Macquarie Valley

Burrendong Dam, Wellington 1154 24.1% 278 6 d/s trib flows continue <20% 100% 0% 6.7% Windamere Dam, Mudgee 367 27% 99 0 Low releases <5% 100% 0% 58% Lachlan Valley Wyangala Dam, Cowra 1217 17% 208 2 Minimum releases <20% 70% 0% 2.2% d/s trib flows, access to UCF and Carcoar Dam, Carcoar 36 17% 6 0 <10% 100% 0% 28% Supp flows ceased

Murrumbidgee Valley Burrinjuck Dam, Yass 1025 44% 449 2 WSP Plan min releases 40% 95% 14% 18% Blowering Dam, Tumut 1604 59% 944 19 WSP Plan min releases <10% 95% 14% 18% Murray Dartmouth, Mitta Mitta (Vic) 3837 51% 1958 8 WSP Plan min releases N/A N/A N/A N/A Hume Dam, Albury 2982 43% 1273 89 WSP Plan min releases <25% 97% 2% 21% *Lower Darling Menindee Lakes, Broken Hill 1633 27% 434 -6 WSP Plan min releases <30% 100% 30% 48% Hunter Valley Glenbawn Dam, Scone 750 39% 291 1 Min release <20% 90% 30% 23% Glennies Ck Dam, Singleton 282 37% 104 -0 Small d/s trib flows <20% 90% 30% 23% Lostock Dam, Gresford 20 100% 20 0 spilling 100% 100% 100% N/A Coastal Area Toonumbar Dam, Kyogle 11 67% 7 0 d/s trib flows continue 100% 100% 100% N/A Brogo Dam, Bega 9 93% 8 -0 Regulated releases 100% 100% 40% N/A Total 17747 36.2% 6433 123

*Total volumes were reported for the Menindee lakes previously which is now changed to active volume.

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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