Regional
water availability
report
Weekly edition 25 May 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 ...... 10
5. Central valley based operational activities ...... 10
5.1 Lachlan valley ...... 13
5.2 Macquarie valley ...... 10
6. Northern valley based operational activities ...... 18
6.1 Namoi valley ...... 19
6.2 Gwydir valley ...... 21
6.3 Border rivers ...... 22
6.4 Barwon-Darling River system ...... 22
7. Coastal valley based operational activities ...... 27
7.1 Bega river ...... 27
7.2 Hunter valley ...... 28
7.3 Toonumbar Dam ...... 30
8. Rural Dam Levels ...... 31
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1. Overview
WaterNSW manages and operates 42 dams 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 Sydney, 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 25 May 2020 was 31.1% of the total active storage capacity. This was an increase of 0.7% since last week.
The total storage level of urban water supplies on 25 May 2020 was 81.8% of the total storage capacity. This was an increase of 0.1% since last week.
2. System risks
Inflows adding to over 565 GL are continuing to flow into Menindee Lakes over the next few weeks and releases to the Lower Darling have reached the Murray River.
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 large 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 deep low pressure system over the Tasman Sea is bringing large surf as well as windy, cool and wet weather to parts of the east. This low is expected to linger offshore, gradually weakening and moving a little further north during Tuesday and Wednesday, before moving away to the east mid- week as a trough skims the south of the state. Meanwhile, a high pressure system near Tasmania extends a ridge across the state's west.
Figure 2a – First 4-day Forecast (26 – 29 May 2020) Figure 2b – Following 4-day forecast (30 May – 2 June 2020)
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Rainfall for the fortnight 30 May to 12 June is likely to be average across western NSW.
There is a much higher chance of a wetter than average June to August for western NSW.
Figure 3 – 3-month rainfall outlook
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4. 4Southern valley based operational activities
4.1 Murray Valley
Storage and release status
• Hume Dam is currently 24% of active capacity, and at min releases of 600ML/d.
• Release downstream of Yarrawonga Weir are at about 6,000ML/day and likely to remain steady over the week.
• The Edward River Offtake flow is currently about 1,200 ML/d and is likely to recede further as Murray flows recede.
• The Gulpa Creek Offtake flows are at about 220ML/d and is likely to recede over the coming days.
• Stevens Weir level is about 4.51m and will marginally vary. Water level upstream of Wakool Canal offtake is about 1.83 m.
• Forest regulators have been closed with the falling river levels.
• Flow downstream of Stevens Weir is about 2,100 ML/day and is likely that flows return to within channel capacity but remain close to channel capacity as Murray Irrigation commenced drainage of their channel system.
• Flows in the Colligen Creek (350ML/day), Yallakool Creek (420ML/day) and Wakool River (50ML/day) and flows are likely to remain relatively steady. On top of the above, MIL is escaping about 100ML/day into the Wakool River.
• Flow in Niemur River at Mallan School is currently about 450ML/d and increasing. Flow will continue to rise due to flow via Werai forest through this week.
• Merran Creek flows upstream of its confluence with Wakool is about 200 ML/day and is likely to gradually increase this week.
• Flow in Wakool River at Stoney Crossing is currently at about 730 ML/day and is likely to gradually increase this week.
• Flow at Balranald is currently about 786 ML/d and will fluctuate over the next week. The end of system target at Balranald for the month of May is 297ML/day.
• Lake Victoria is currently holding about 406 GL or 53% of active capacity. The flow to South Australia is about 5,700ML/d.
Environmental water operations
• eWater delivery has now ceased into Wakool-Yallakool system and into Colligen-Niemur system.
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Water availability
• The latest Murray Water Allocation Statement 15 May 20 confirmed that general security allocation have increased by 3 per cent.
Drought operation measures
• The NSW Murray regulated river water source has 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.
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4.2 Lower Darling valley
Storage and release status
• Menindee Lakes system collectively holds about 27% of total capacity, and is releasing about 220 ML/d.
• The status of individual lakes: Lake Wetherall - 67%, Tandure – 84%, and Lake Pamamaroo – 118%, Copi Hollow – 133%; while Lakes Menindee and Cawndilla remain dry.
• As per the Water Sharing Plan, the planned minimum flows for the months of May and June will be 200 ML/day measured at Weir-32.
• Water is being transferred from Lake Wetherell to Lake Pamamaroo to equalise the level in these sections of the storage. The purpose of this is to minimise the surface area and area of inundation for the volume in storage, therefore minimising losses from the storage system. The transfer is as per standard filling procedure.
• Inflows to the lakes commenced on 10 March 2020 and so far about 642 GL (with updated ratings) has reached Wilcannia.
• Current forecast in the Barwon-Darling system indicates that in total about 570 GL is expected to reach the lakes including the water in transit.
Water availability
• To date the current inflows have not resulted in the storage volume reaching 640GL and are currently not forecast to reach this trigger in the current event. As such the storage remains in NSW control and the resources shall be managed for Lower Darling operations.
• Water allocations for 2019/20 have been increased to 100% for domestic and stock licence holders, local water utility licence holders, and high security licence holders. General security has now increased to 30% and access to carryover is available.
Drought operation measures
• The temporary water restriction that came into effect on 4 December 2018 limiting the taking of water to town water, domestic and stock, permanent plantings, and, from Copi Hollow, high security licences has been repealed on 30 March 2020. DPIE Media Release
• The Lower Darling regulated river water source is assessed to be in drought Stage 2.
Water quality
• Amber Alert for Copi Hollow (site N1094) and Darling river u/s of Weir 32 (site N1171
• Green alert for Lake Wetherell (site 1, 2, 3 and 4), Wilcannia (N1042), Darling River at Weir 32 (N1086) and Daring River Pumping Station @ Menindee (N1095).
– For more information visit: Water Quality Algae.
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Planned supply interruptions:
None
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4.3 Murrumbidgee valley
Storage and release status
• Burrinjuck Dam is currently at 41% of active capacity, releasing about 560 ML/d transparent releases.
• Blowering Dam is currently at 50% of active capacity, releasing about 560 ML/d. The release is likely to remain steady as per transparent release rules.
• With the early May rainfall an announcement has gone out for a two-day supplementary event starting on the 3rd May and completed in the Murrumbidgee River on 24th May. However, the event in Yanco-Billabong Creek system is still progressing and more likely to end by first week of June 2020.
• The Beavers Creek offtake regulator is fully open as per the work approval conditions. However, due to lower flows at Wagga (about 1,500ML/d), the flow at Mundowey is negligible.
• Berembed Weir is currently at operational full supply level of about 4.96m and will remain steady over the week.
• Bundidgerry storage is currently at about 4.17 m and is likely to reduce to about 4.0 m over the week.
• Gogeldrie Weir is currently at about 3.36 m and is being drawn down for routine winter maintenance activities. The gates are expected to be taken out of water by end of May 2020 and the weir will be returned to service by 1 July 2020.
• Hay Weir is currently at about 8.16m and is being used to capture surplus flows in the system. The weir is expected to be at operational full supply level of 8.6m by later this week.
• Maude Weir is at about 3.2 m and will increase to about 3.5m over the week. The maximum water level at Maude will be maintained below 3.7 m in order to keep the Nimmie-Caira offtake channels drier for maintenance works in the Nimmie Creek Regulator.
• Currently, the Redbank Weir level is about 5.68 m. The level is to remain steady.
• Flow at Balranald is currently about 786 ML/d and will fluctuate over the next week. The end of system target at Balranald for the month of May is 297ML/day.
• The current diversion into Yanco Creek is about 250 ML/d and is likely to remain steady.
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 large.
• Planned environmental water flow rules are fully complied with at both Balranald and Darlot.
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• Held environmental water is being delivered to North Redbank assets via N. Redbank Channel (about 500ML/day) and Pato’s pipe (about 50ML/day).
Water availability
• For Inter Valley Transfer (IVT) account from Murray to Murrumbidgee refer to WaterNSW website WaterNSW website
• As per the Murrumbidgee Water Allocation Statement 15 May 20 there is a general security increase of 5%, with cumulative allocations for 2019/20 to general security licences now totalling 11% of entitlement in the Murrumbidgee regulated water source. Allocation is at 100% for towns and 95% for high security. General security licence holders in the Murrumbidgee have full access to water carried over from 2018-19, which is a volume equivalent to about 8% of general security share component.
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.
Water quality
• Potential Blue Green Algae issues:
– Burrinjuck Dam at State Park and Woolgarlo are on an Amber alert level, while Station 1 (Dam Wall), Downstream 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:
• As part of the coating program, the Nimmie Creek offtake gates would be removed for a period of 5-weeks stating from 1 June 2020. Supply to North Caira, South Caira and Nimmie Creeks are impacted. The Nimmie Creek regulator is expected to be returned to service by mid-July 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 Mid-July.
• Planning for painting super-structure of the Maude Weir and Gogeldrie weirs under the coating Programme is in final stages.
• Planning is underway to commence regular winter maintenance of Gogeldrie Weir. In preparation of the planned maintenance, the Gogeldrie weir is being gradually lowered and
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gates are expected to be clear of water by 30th May 2020. The weir would be reinstated by first week of July 2020.
• Planning is underway to commence regular winter maintenance of Berembed Weir. In preparation of the planned maintenance, the Berembed Weir would be gradually lowered starting from 22 June 2020 and gates are expected to be clear of water by 3 July 2020. The weir would be reinstated by end of July 2020.
• Planning is underway to commence regular winter maintenance of Hay Weir. In preparation of the planned maintenance, the Hay Weir would be gradually lowered starting from 30 June 2020 and gates are expected to be clear of water by last week of July 2020. The weir would be reinstated by mid-August 2020.
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5. Central valley based operational activities
5.1 Lachlan valley
Storage and release status
• Carcoar Dam is currently 15% of capacity and releasing 2ML/d.
• Wyangala Dam is currently 14.9% of capacity and releasing around 80ML/d. Releases are forecast to remain at 80M/d for rest of the week.
• Lake Cargelligo is currently around 93% of capacity and will stay around 93% by end of the week.
• Releases downstream of Brewster Weir are reduced to around 30ML/d. Releases are forecast to remain around 30-40ML/d during the week.
• Willandra Ck flow ceased from 1st December 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. Some of these flows are diverted into Lake Cargelligo and most of the flows are being diverted into Lake Brewster outflow wetlands and into the main cell from Lake Brewster weir.
Environmental water operations
• As part of the 2019–20 spring pulse, 2GL of environmental water was held in Brewster Weir to help maintain the habitat for the endangered population of olive perchlet over summer.
• This environmental water is now being released from Brewster weir piggy backing the recent rainfall events. An another ~400ML of licensed environmental water will also be released downstream of Brewster weir pool to support a wetland refugia upstream of Oxley for the arrival of migratory birds in spring.
• Releases for environmental water from Brewster weir ceased Monday 18th May and are now passing through Booligal.
• 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 313GL is required in May before a further allocation can be made in the Lachlan River. Inflows received in May so far are around 34GL.
• The DPIE Water Allocation Statement (WAS) published on 15 May 2020 provided expected 1 July 2020 water availability for 2020-21 water year.
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• Full (100%) allocation for all Local Water Utilities and Domestic & Stock license holders • At least 70% allocation for High Security license holders.
• Conveyance will receive its commensurate allocation in accordance with the water sharing plan.
• No allocation to General Security water users will be possible. • 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.
• The detailed October WAS by Dept Planning, Industry & Environment can be viewed at: WAS
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 124 114 313
By end of July 124 139
By end of Aug 124 219
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
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• 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.
• 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 event.
Water Quality
• Latest BGA samples show that Lake Cargelligo Boatshed is on Amber alert. However, Lake Cargelligo TWS, Lake Cargelligo Outlet, Lake Cargelligo intake d/s of Curlew Water is at Green Alert.
• Wyangala Storage results results (6th May) show that overall productivity has declining at all sites. Microcystis sp. remains the dominant species but in much smaller concentrations. Downstream showed low level detections of the same species. The storage remains at amber alert awaiting another clear result.
• 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 will commence in the first week of July 2020 and is planned to last for one week. During this period, the weir gates will be fully raised and a flow around 180 ML/d would be maintained past the weir, this will meet the downstream requirements.
• In preparation for the works the Jemalong Weir pool will be lowered to normal river levels commencing the last week of June. As irrigation demand is normally low in June/July, the lower flows resulting from planned works should not cause any disruptions.
Wyangala Dam maintenance
• There will be an outage at Wyangala Dam starting the first week of June ending second 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.
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5.2 Macquarie valley
Storage and release status
• Burrendong Dam is at 21.4% of capacity and currently releasing around 40ML/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 from 1 April to 25 May are around 163GL.
• Windamere Dam is currently 27.1% of capacity (100GL) and releasing 25ML/d. Releases are forecast to stay around 20- 30 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 June 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 accounts in Burrendong were suspended to extend supplies for towns and critical industries. Link. This suspension is now being repealed and both active and translucent account water will be available
Water availability
• The DPIE Water Allocation Statement (WAS) published on 13 May 2020 provided increased water availability for this year.
• Local Water Utility (LWU), Stock & Domestic (SD) licences and High Security allocations have been lifted to 100 per cent of entitlement for 2019-20.
• The temporary water restriction on Macquarie general security water accounts is being amended to allow the transfer of 30 per cent of the drought sub-account balance to the active account for use.
• All higher security licence categories forecast to receive100% allocation on 1July 2020.
• Trade from the Cudgegong down to the Macquarie water source has been closed as an emergency drought measure to protect Burrendong Dam supplies and particularly water security in the Macquarie for critical needs. The restriction can now be lifted, allowing trade to resume in accordance within the water sharing plan.
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• 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 complete, from the recent rainfall events and contributions from downstream tributaries.
• The actual inflows to Burrendong Dam since the last AWD in August 2017 totalled about 273 GL to end of April 2020. This was just 50% of the previous record low inflow for the 33 months ending in April.
• 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 21st April show low productivity at all upstream sites. Minor counts of benign cyanobacteria dominate the assemblage. A detection of Microcystis sp. was noted in the Mookerawa arm. Few cyanobacteria were detected downstream. Storage remains at green alert.
• Windamere dam results for 12/05 show the assemblage at the Dam Wall is dominated by low counts of Microcystis sp. Results from mid-lake continue to show elevated counts of the same species with few other cyanobacteria detected. Downstream showed only a minor cyanobacterial detection. Windamere remains on red 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
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6. Northern valley based operational activities
6.1 Namoi valley
Storage, release and inflow status
• Split Rock Dam is at 4.58 % of active capacity, is currently releasing 2ML/d; releases have recommenced in April.
• Keepit Dam is at 14.06% of active capacity, releases have ceased after recommencing briefly for limited domestic and stock near the dam.
• Chaffey Dam is at 14.0% of active capacity and currently releasing 10ML/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.
• Environmental releases of 30ML per week continue in the Peel Valley.
Water availability
• Limited supplementary and uncontrolled flow access was available in the Namoi and Peel Valleys in recent weeks. See announcements here.
• There is a shortfall of more than 31 GL (down from 35GL in March) before there is likely to be an AWD increment in the Lower Namoi valley.
• The Water Allocation Statement by DPIE (dated 15th April 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%.
• The latest Water Allocation Statement by DPIE (dated 7th May 2020) confirmed that in the Upper Namoi local water utility and D&S have 100%, while high security has received 100% allocation and the general security a 50% allocation – as the Split Rock Dam storage volume has exceeded the 5 % full trigger (as per the water sharing plan). The restrictions on access to carryover have been repealed.
• Lower Namoi local water utility and D&S have 100%, high security has 100% and general security has 0%. The restrictions on access to carryover have been repealed.
Drought operation measures
• The Peel valley is in drought stage 4. Drought measures are underway, including restricting flows below Dungowan from 30 November to secure town water supply. Current operational targets below Dungowan are for very low flows over the temporary weir once every 4 days. Commissioning of the Chaffey to Dungowan pipeline has commenced in mid-April.
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• 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 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 an Amber alert in the storage,
• Keepit Dam is on a Green alert in the storage, and
• Chaffey Dam is on an Amber 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
• Copeton Dam is at 12.7% of active capacity and is currently releasing 21ML/d.
• There are flows in the Horton River at Rider, the first flows since December 2017 and the Gwydir River and Carole/Gil have had flows run to end of system.
• For regular updates, refer to the Operations Update page in WaterNSW website.
Environmental water operations
• Block release containing high security, ECA and environmental water, was finalised at the dam on 10th of January.
Water availability
• Limited supplementary access events have been announced, see copies here Supplementary Announcements.
• The latest Water Allocation Statement by DPIE -Water (dated 7th May 2020 ) confirmed that - a result of the inflows in April - there is now enough water to make an allocation of 1.9 per cent of entitlement to General Security (GS) licence holders. This is the first allocation able to be made for general security licences since February 2018.
• The local water utility and domestic and stock access licence holders have 100% of entitlement. High security has 100% and general security have 1.9%. These licence holders have access to general security account water carried over from the previous water year as well.
Water quality
• Recent Blue Green Algae (BGA) sampling at Copeton shows Copeton on an Amber alert in the storage and no alert downstream of 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
• Pindari Dam is at 11.6% of capacity and releasing around 13ML/d (minimum release).
• Glenlyon Dam is at 13.5% 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 has generated significant flows across the Northern valleys. Catchment is wet now and response from further rainfall will be quicker.
• Significant improvement noted in the 1 May 2020 resource assessment due to recent inflow event. Draft resource assessment indicates that there is no shortfall. If inflow continues, there is a possibility to announce some General Security allocation in near future.
• 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 Available Water Determination (AWD) for 2019-20 is 100% for towns and high security, while general security A-class and general security B-class is zero. Total carryover into 2018-19 is around 1.8% of general security share components.
• Supplementary access was allowed in Border Rivers due to recent rainfall event. Refer to supplementary announcement page in WaterNSW website for details.
• General Security customers can access GS account balance now. Refer to Operations update page in WaterNSW website for details.
Drought operation measures
• The Border Rivers is in drought Stage 3. Customers are advised that if dry conditions persists, 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 red 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. For regular updates, refer to the Operations Update page in WaterNSW website.
• 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
• Flow has resumed between Mungindi and Wilcannia and access is allowed, as per licence conditions, for customers for all management zones.
• Refer to the Barwon-Darling flow class map for up to date information on licence class availability.
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 will be regularly updated as required.
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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 79,544 80,000 – 80,500 15 Feb 2020 Inflows are from the Border Rivers
Presbury 70,506 70,800-71,200 5 Feb 2020
Mogil Mogil 211,111 211,300-211,700 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 249,232 249,500 – 250,000 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 271,045 271,400 – 272,000 7 Feb 2020 Gain from localised inflows
Walgett 378,024 378,500 –379,500 9 Feb 2020 Expected total inflows (observed and forecast) are about 92.5 GL from Namoi at Goangra
Boorooma 413,829 414,000 – 415,000 13 Feb 2020 Flows were out of bank
Geera 527,992 528,500 - 530,000 12 Feb 2020 Significant inflow from Castlereagh River and Marthaguy Ck from April rainfall
Brewarrina 493,846 494,500 – 496,000 16 Feb 2020
Beemery 628,762 630,000 – 635,000 18 Feb 2020 Around 32 GL inflow arrived from Bokhara. Gain from localised inflows.
Warraweena 764,687 768,000 – 773,000 19 Feb 2020 Based on observed flows at NSW gauges, around 175-176 GL inflow from Culgoa.
Bourke 708,207 715,000 – 720,000 20 Feb 2020
Water availability weekly report 24
Louth 705,632 710,000 – 716,000 24 Feb 2020 Around 46-48 GL inflow from Warrego
Tilpa 663,328 670,000 – 678,000 28 Feb 2020
Wilcannia 641,214 650,000 – 660,000 5 Mar 2020
Lake Wetherell, 557,242 565,000 - 580,000 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.
Water availability weekly report 25
WaterNSW HYPLOT V133 Output 25/05/2020 Period 5 Month 01/01/2020 to 01/06/2020 2020 416001 BARWON R @ MUNGINDI 141.00 6 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 416050 BARWON U/S PRESBURY 141.00 6 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 422004 BARWON @ MOGIL MOGIL 141.00 6 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 422003 BARWON @COLLARENEBRI141.00 6 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 422025 BARWON @ TARA 141.00 6 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 422001 BARWON @ DANGAR BDGE141.00 6 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 422026 BARWON @ BOOROOMA 141.00 6 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 422027 BARWON @ GEERA 141.00 6 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 Jan Feb Mar Apr May
WaterNSW HYPLOT V133 Output 25/05/2020 Period 5 Month 01/01/2020 to 01/06/2020 2020 422002 BARW ON @ BREW ARRINA 141.00 6 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 422028 BARWON @ BEEMERY 141.00 6 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 425039 DARLING@W ARRAW EENA 141.00 6 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 425003 DARLING@BOURKE TOW N 141.00 6 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 425004 DARLING@LOUTH 141.00 6 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 425900 DARLING@TILPA 141.00 6 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 425008 DARLING@WILC. MAIN C 141.00 6 Hour Mean Discharge (ML/d) CP 18000 14400 10800 7200 3600 0 Jan Feb Mar Apr May
Water availability weekly report 26
7. Coastal valley based operational activities
7.1 Bega river
Storage and release status
• Brogo Dam is at 98.6% 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 19.
• Due to heavy rainfall on the weekend of 8 and 9 February 2020 Brogo Dam filled to 100%. In these circumstances, full water security has been restored, and the temporary water restrictions on general security was lifted on 12 February 2020.
• This has also resulted in increased allocation for general security licence by 20 per cent, which makes the total allocation to 60 per cent of entitlement. The increase in GS allocation was announced on 24th February 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 shows low productivity across the storage mostly represented by green alga. No cyanobacteria were detected upstream or downstream. Storage remains on green alert.
Planned supply interruptions:
• Nil
Water availability weekly report 27
7.2 Hunter valley
Storage and release status
• Glenbawn Dam is currently at 39% of capacity and releasing around 20ML/d. Releases are forecast to increase to up to 400ML/d if AGL order water, otherwise releases will remain low.
• Glennies Creek Dam is at 37% of capacity and releases are currently around 60ML/d. Releases are forecast to remain steady during the week after rainfall events contributed to instream flows and reduced demand.
• Lostock Dam is at 100% of capacity.
Environmental water operations
• No current additional operations.
Water availability
• General Security licenses in the Hunter Valley received 95% allocation on the 1 July 2019 while all other categories received 100%.
• Paterson valley allocations are 100% for all licence categories.
• Water Allocation Statement published on 20 May 20, by Department of Planning, Industry and Environment provided resource outlook for 2020-21.
• As per 20 May WAS, high security and general security licences can expect an opening allocation of 85% and 20% respectively.
• All other higher priority licences including Local Water Utilities, Major Water Utilities, and Domestic and Stock water access licenses can expect full (100 per cent) allocations.
• The Environmental Water Allowance will be credited with 20 gigalitres (GL) in accordance with the water sharing plan.
• Unused water in accounts (Carryover) can be carried forward (to allowable limits) in accordance with the rules of the water sharing plan and will be fully deliverable in 2020-21.
• General security licence holders can carry over a maximum of 25 per cent of their share component and it is expected that average carryover this year will be 20-25 per cent of entitlement.
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 availability weekly report 28
Water quality
• Recent BGA sampling at Hunter storages indicates a green alert is maintained at Glennies Creek and Lostock., however an amber alert is for Glenbawn.
Planned supply interruptions:
• Nil
Water availability weekly report 29
7.3 Toonumbar Dam
Storage and release status
• Toonumbar Dam is at 67% of capacity and releasing about 10 ML/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) in Casino on 10th March 2020 and advised the stakeholders of the current situation and future operations Plan.
• Full allocations already announced for all entitlement holders in 2019-20 are confirmed and fully deliverable this year, while high priority commitments for 2020-21 are also assured.
• Recent rain and forecast weather conditions indicate a possible shift in weather patterns following months of extreme dry weather. If Toonumbar storage levels are maintained or increased in coming months, there will be a strong possibility of full general security allocation for 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:
• Nil
Water availability weekly report 30
8. Rural Dam Levels
The following table shows the status of water supplies at 25 May 2020.
Likely- Weekl hood Cap- y River Valley Current Status Comments of fill Allocations for 2019/20 acity chang and e (GL) spill
% of C’over Active High Gen. Storage Dam, Nearest Town (GL) active Supply Issues avail @ (GL) Security Security capacity 1/7/19
Border Rivers Glenlyon Dam, 253 13% 34 -0 d/s trib flows continue <20% 100% 0% <1% Stanthorpe (Qld)
Pindari Dam, Inverell 312 12% 36 0 d/s trib flows continue <20% 100% 0% <1%
Gwydir Valley Copeton Dam, Inverell 1346 13% 171 0 d/s trib flows continue <5% 100% 1.9% 5% Namoi Valley
Keepit Dam, Gunnedah 419 14% 59 1 d/s trib flows continue <20% 100% 0% 5%
Split Rock Dam, Manilla 394 5% 18 0 d/s trib flows continue <5% 100% 50% 22%
Chaffey Dam, Tamworth 98 14% 14 0 d/s trib flows continue <50% 50% 0% N/A Macquarie Valley Burrendong Dam, d/s trib flows recession 1154 21.4% 247 3 <20% 100% 0% 3% Wellington continue Windamere Dam, 367 27% 99 -0 Regulated releases. <5% 100% 0% 54% Lachlan Valley Wyangala Dam, Cowra 1217 15% 180 2 C’over restricted to 57% <20% 87% 0% 15% Carcoar Dam, Carcoar 36 15% 5 0 d/s trib flows, access to <10% 100% 0% 38% UCF d S fl
Murrumbidgee Valley Burrinjuck Dam, Yass 1025 41% 420 2 Min Planned eWater 40% 95% 11% 8% Blowering Dam, Tumut 1604 50% 795 -0 Min Planned eWater <10% 95% 11% 8% Murray Dartmouth, Mitta Mitta 3837 49% 1871 16 Minimum releases N/A N/A N/A N/A Hume Dam, Albury 2982 24% 707 72 Minimum releases <25% 97% 3% 18% Lower Darling Menindee Lakes, Broken Water Sharing Plan min 1633 27% 429 29 <30% 100% 30% 19% Hill releases Hunter Valley Glenbawn Dam, Scone 750 40% 297 0 d/s trib flows <20% 100% 95% 23% Glennies Ck Dam, 282 37% 103 -0 Small d/s trib flows <20% 100% 95% 23% Lostock Dam, Gresford 20 100% 20 0 spilling 100% 100% 100% N/A Coastal Area Toonumbar Dam, Kyogle 11 66% 7 -0 d/s trib flows continue 100% 100% 100% N/A Brogo Dam, Bega 9 98% 9 -0 Spilling 100% 100% 60% N/A Total 17746 31.1% 5521 125
Water availability weekly report 31
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
More information
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Water availability weekly report 32