Regional water availability report · 8. Rural Dam Levels ... The total storage level of urban water supplies on 14 September 2020 was 95.3 percent of the total ... with the exception

1

Regional

water availability

report Weekly edition

14 September 2020

Water availability weekly report 2

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 ........................................................................................................................................... 15

6. Northern valley based operational activities ................................................................................... 17

6.1 Namoi valley ................................................................................................................................................... 16

6.2 Gwydir valley .................................................................................................................................................. 18

6.3 Border rivers ..................................................................................................................................................... 19

6.4 Barwon-Darling River system ........................................................................................................................ 19

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

7.1 Bega river ........................................................................................................................................................ 22

7.2 Hunter valley ................................................................................................................................................... 23

7.3 Toonumbar Dam ............................................................................................................................................ 24

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


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 14 September 2020 was 49.6 percent

of the total active storage capacity. This was an increase of 0.3 percent since last week.

The total storage level of urban water supplies on 14 September 2020 was 95.3 percent of the total

storage capacity. This was a decrease of 0.8 percent since last week.

2. System risks

Rainfall along the southern and central west slopes and ranges over the previous weeks has

maintained stream flows and inflows to the dams in the Murray, Murrumbidgee, Lachlan and

Macquarie valleys. Operational plans are being reviewed as these inflows accumulate.

WaterNSW is working with BOM in assessing the likelihood of filling storages, with the positive

seasonal rainfall forecasts, particularly for Burrinjuck Dam, 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.


3. Climatic Conditions

Figure 1 - Weekly rainfall totals

A high-pressure system will move across southeast Australia to the Tasman Sea today, while a weak

coastal trough decays. The high is expected to maintain a ridge across New South Wales through

Wednesday. before weakening on Thursday as a cold-front skims across the state's south. A new

high is then forecast to move across Tasmania to the Tasman Sea on Friday, as a broad low-

pressure system approaches from the west. For the first part of the week, the majority of the state is

predicted to remain dry, with the exception of negligible rainfall along the coastal fringe. As the

week progresses, the entire state is forecast to receive between 10 and 50 mm of rainfall.

Figure 2a – First 4-day forecast (15 – 18 September 2020) Figure 2b – Following 4-day forecast (19 – 22 September 220)


Climate outlook overview

Issued 10 September 2020

Wetter September to November for much of NSW

• The fortnight of 14 to 27 September is likely to be wetter than average for much of NSW

• The outlook for September to November indicates a wetter than average three-month period

for NSW (a greater than 65 - 80 percent chance).

Figure 3 – 3-month rainfall outlook

A La Niña ALERT remains.

Key indicators of the El Niño–Southern Oscillation are at or approaching La Niña thresholds. This includes

further cooling in the central tropical Pacific Ocean over the past fortnight to levels just shy of the La Niña

thresholds, while the Southern Oscillation Index (SOI) has been at La Niña values since late August.

All climate models surveyed by the Bureau indicate further cooling is likely, and that La Niña thresholds are

likely to be met in October and will continue until at least the end of the year.

Bureau climatologists will continue to closely monitor model outlooks and conditions in the tropical Pacific for

further signs of La Niña development.


4. 4Southern valley based operational activities

4.1 Murray Valley

Storage and release status

• Hume Dam is currently at 64 percent of active capacity and at minimum

releases of 5,500 ML/d.

• Release downstream of Yarrawonga Weir is at approximately 7,000 ML/d and is likely to vary

between 6,500 and 7,500 ML/d over the next week.

• Due to receding tributary inflows (particularly flows from the Goulburn R), increasing irrigation

demands due to warmer temperatures, supplementary access in the upper- and mid-reaches

of the Murray and Edward systems have also ceased. Lake Victoria is being filled from

unregulated flows remaining in the lower part of the system with the expectation that, without

rainfall unregulated flows may cease within the coming week.

• The Edward River offtake flow (1,000 ML/d) will vary in line with Murray River water levels.

• The Gulpa Creek offtake flow (240 ML/d) will remain below the operational channel capacity of

250 ML/day.

• Stevens Weir level is at approximately 4.5 m and is likely to vary marginally. The water level

upstream of Wakool Canal offtake is at approximately 1.75 m.

• Flow downstream of Stevens Weir is approximately 800 ML/d and is likely to reduce to

approximately 600 ML/d over the week.

• Flows into Colligen Creek (170 ML/d) and Yallakool Creek (200 ML/d) to Wakool River (25 ML) will

continue to be relatively steady.

• Flow in Niemur River at Mallan School is currently at approximately 200 ML/d and the flow is likely

to vary marginally over the week.

• Merran Creek flows upstream of its confluence with Wakool at approximately 130 ML/d and the

flow is likely vary marginally.

• Flow in Wakool River at Stoney Crossing is currently at approximately 550 ML/d and is likely to

increase over the week.

• Flow at Balranald is currently at approximately 1,350 ML/d and will fluctuate a little to meet the

end of system target of 1,300 ML/day for September 2020.

• Lake Victoria is currently holding approximately 665 GL or 98 percent of active capacity. The

lake is effectively full under the Lake Victoria operating strategy that maintains airspace in the

lake while unregulated flows ensure the lake can be filled. The flow to South Australia is at

approximately 9,130 ML/d.

https://www.waternsw.com.au/supply/regional-nsw/supplementaryhttps://riverdata.mdba.gov.au/system-view


Environmental water operations

• Plans to commence eWater spring flow delivery into Wakool-Yallakool system and into the

Colligen-Niemur system have been proposed to fit in with the proposed Murray watering event,

the dates of which are not yet finalised.

Water availability

• The Water Allocation Statement (WAS) by the NSW Department of Planning, Industry and

Environment (DPIE) (dated 15 September 2020) 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. There is a three percent increase to all General Security (GS)

entitlements with a commensurate increase in the Conveyance entitlement in the NSW Murray

Regulated River water source. This brings the total allocation for 2019-20 to 15 percent and with

average GS carryover of 21 percent, it means NSW Murray total GS water availability has

reached 36 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:

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 an Amber Alert Level.

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.

https://www.industry.nsw.gov.au/water/allocations-availability/droughts-floods/update/critical-valleys-in-droughthttps://www.waternsw.com.au/about/newsroom/2019/algal-red-alert-issued-for-lake-humehttps://www.waternsw.com.au/water-quality/algae


4.2 Lower Darling valley


• The Menindee Lakes system collectively holds approximately 463 GL of

total volume of water (or 26 percent of active capacity) and is releasing

approximately 410 ML/d.

• The status of individual lakes are as follows: Lake Wetherell – 67.9 percent, Tandure – 84.4

percent and Lake Pamamaroo – 116.1 percent, Copi Hollow – 128 percent, while Lakes

Menindee and Cawndilla remain dry.

• The Water Sharing Plan minimum flows for the months of May 2020 to October 2020 is 200 ML/d

measured at Weir-32. An additional 200 ML/d will be delivered at Weir-32 as ordered by the

environmental water holder until the end of October 2020.

• Transfer of additional inflows arriving at Lake Wetherall to Lake Pamamaroo has commenced

and is likely to continue for few days until the levels in both these lakes equalise. The action has

been taken to minimise the lake evaporation (Lake Pamamaroo has got relatively smaller

surface area and greater mean depth).

Water availability

• To date the current inflows have not resulted in the total storage volume reaching 640 GL 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 WAS by DPIE (dated 15 September 2020) 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.


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

Water quality

• A Green Alert Level has been assessed 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 at Menindee (N1095).

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


• Nil.

https://www.industry.nsw.gov.au/water/allocations-availability/allocations/summaryhttps://www.waternsw.com.au/water-quality/algae


4.3 Murrumbidgee valley


• Burrinjuck Dam is currently at 80 percent of active capacity, releasing

approximately 5,000 ML/d to meet the system demands for irrigation and

environmental orders.

• Blowering Dam is currently at 78 percent of active capacity releasing approximately 3,000 ML/d

to meet the system demands for irrigation and environmental orders.

• The Beavers Creek offtake regulator gates are fully open and are aimed at achieving an

average flow of about 600 M/d at Kywong during the month of September 2020 as per the work

approval conditions.

• Due to the tributary flows and translucent releases from Burrinjuck Dam in late August 2020 an

eight-day supplementary event in the valley was announced. The event has concluded in the

Murrumbidgee river, Colombo Creek and Yanco Creek. However, the event is continuing in the

lower end of Billabong Creek.

• Berembed Weir is at full supply level (4.96 m) and will be drawn down to 3.7 m over the week to

meet downstream demands.

• Bundidgerry storage is currently at approximately 3.87 m and will vary marginally over the week

depending on the diversions by Murrumbidgee Irrigation.

• Golgeldrie Weir is at approximately 6.00 m and will be drawn down to 5.7 m over the week to

meet downstream demands.

• The Tombullen storage (2.27 m) is being drawn down to meet the downstream demands. Water

is being released at a rate of about 1,100 ML/d and the release rates will gradually reduce to nil

as the storage is fully drawn down over the next two weeks.

• Hay Weir is at approximately 7.7 m. The water level is likely to vary within 300 mm/d over the next

few weeks as the weir would be used for active re-regulation. The water stored in the Weir will be

used to meet downstream demands until the Weir level reaches 6.0 m before restoring to 6.5m,

which is the operational target until the start of summer season.

• The water level at Maude Weir 5.6 m to deliver environmental water into the Nimmie Creek (250

ML/d) and North Caira (500 ML/d). The weir level is likely to vary between 5.3 m and 5.6 m.

• Currently, the Redbank Weir water level is at approximately 5.65 m. The Weir will remain relatively

steady over the next few weeks to deliver environmental water to assets in the Lowbidgee area.

• Flow at Balranald is currently at approximately 1,350 ML/d and will fluctuate a little to meet the

end of system target of 1,300 ML/day for September 2020.

• The current diversion into Yanco Creek is at approximately 450 to 480 ML/d and will remain

relatively steady for the rest of the week. The flow into the Yanco arm below Tarabah Weir will

remain approximately 70 ML/d, while the split into the Colombo arm will be approximately 380

ML/d to supply water to Forest Creek for environmental flows.



• The Burrinjuck Dam Translucent Rules operate between 22 April 2020 and 21 October 2020. These

rules mean that a proportion of daily inflows are released, which means releases can be larger

when inflows are higher.

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

• A significant eWater delivery of approximately 59,200 ML (34,000 ML of Planned Environmental

Water, 19,000 ML of Held eWater and 6,200 ML of supplementary) over a period of

approximately 15 weeks commenced on 6 July 2020 via Yanga 1AS into Lowbidgee.

• A second event to deliver approximately 6,800 ML (5,800 ML of Held eWater and 1,000 ML of

supplementary) through Waugorah 1ES, commenced on 23 July 2020 and will continue at a rate

of approximately 50 to 100 ML/d. The event is expected to run for more than 12-weeks.

• A third event to deliver approximately 21,500 ML (10,000 ML of Planned Environmental Water,

12,500 ML of Held eWater and 4,000 ML of supplementary flows) commenced on 28 July 2020 at

the Nimmie Creek offtake. The event will continue for ten weeks.

• A fourth event to deliver approximately 23,500 ML (9,500 ML of Planned Environmental Water,

10,000 ML of Held eWater and 4,000 ML of supplementary flows) commenced on 17 August 2020

to Lowbidgee assets via North Redbank Channel.

• A fifth event to deliver approximately 5,800 ML (800 ML of supplementary flows and 5,000 ML of

Planned Environmental Water) commenced on 31 August 2020 at the Warriston Weir in the

Forest Creek.

• A sixth event to deliver 60,900 ML (45,500 ML of Planned Environmental Water, and 6,000 ML of

supplementary flows) is being delivered to North Caira channel since the end of August 2020.

• Total combined environmental water orders for the current events stand at approximately

187,000 ML including planned eWater, held eWater and supplementary (Lowbidgee category).

Water availability

• For the Inter Valley Transfer (IVT) account from Murray to Murrumbidgee, please refer to the

Murrumbidgee IV Account Status section of WaterNSW website.

• The WAS by DPIE (dated 15 September 2020) confirmed that all high priority entitlements have

received full opening allocations as per the Valley’s Water Sharing Plan. This includes all LWU, D

& S and HS licences. GS licence holders have received an increase in allocation of two percent

taking the total allocation to-date to 46 percent. Carryover is fully available and estimated to be

approximately 348 GL or 18 percent of GS entitlement on average. Conveyance entitlements

have received commensurate increase in allocations as per the Water Sharing Plan.

• Supplementary event has ended in most part of the river system except for the lower Billabong

creek. The dates of access for different river sections are published on approval from DPI&E.

https://www.waternsw.com.au/customer-service/ordering-trading-and-pricing/trading/murrumbidgeehttps://www.waternsw.com.au/supply/regional-nsw/supplementary



• 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 persist.

Water quality

• Potential Blue Green Algae issues:

Burrinjuck Dam at Station One (Dam Wall), Downstream, Burrinjuck Water State Park, Woogarlo

and Goodhope are at Green Alert Level. Blowering Dam is at Green Alert Level.

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

Unplanned supply interruptions:

• Nil


• Painting of the Maude Weir Super Structure has started and will be completed by 30 October

2020. The Painting program for Gogeldrie started on 30 June 2020 and will continue until mid-

January 2021. However, the maintenance activity under the coating program is not expected

to impact normal River Operations and Weir levels.

https://www.industry.nsw.gov.au/__data/assets/pdf_file/0007/270772/WAS-Murrumbidgee-190815.pdfhttps://www.waternsw.com.au/water-quality/algae


5. Central valley based operational activities

5.1 Lachlan valley


• Carcoar Dam is currently at 29.8 percent of capacity and is releasing

approximately 2 ML/d.

• Wyangala Dam is currently at 58.7 percent of capacity and is releasing approximately 14 ML/d.

Releases are forecast to remain at 10-20 ML/d for the rest of the week as downstream tributary

flows are meeting all demands.

• Lake Cargelligo is currently at approximately 77 percent of capacity and will remain steady at

approximately 77 percent for the rest of the week.

• Releases downstream of the Brewster Weir are around 4,000 ML/d. Releases are forecast to

remain between 3000-4000 ML/d during the week. The flows passing through Lake Brewster weir

are translucent flows which finish Wednesday morning and followed by licenced environmental

water releases.

• Good tributary inflows have resulted from recent rain events. The delivery of S&D replenishment

flows have been commenced into Willandra Ck, Merrowie Ck, Merrimajeel and Muggabbah.

These S&D flows will continue to completion, after the translucent flow event, if required.

• The recent rain and tributary flows downstream of the dam have produced some surplus flows.

These flows are being passed as translucent flows below Lake Brewster and a small portion is

being diverted into the Lake Brewster Outflow Wetlands and into the main cell from Lake

Brewster Weir. The current Lake Brewster storage volume is 63 percent of capacity with a volume

of approximately 92,000 ML.


• Due to drought conditions, the end of system daily environmental flow requirements in the

Belubula River have been suspended and are only being met intermittently with contribution

from tributaries. However, due to recent rain and tributary inflows since February 2020, flows past

Helensholme are more than minimum required.

• Under the environmental water provisions of the Lachlan Water Sharing Plan, once 250 GL of

inflows are reached for the calendar year, translucent flow rules are triggered. With the recent

rain that continued from the weekend of 8-9 August 2020 the translucent condition has been

triggered and delivery of translucent water is under way from Lake Brewster instead of

Wyangala Dam. For more information on trigger and delivery of translucent flow, please visit the

relevant section of the WaterNSW website.

• The rules require releases of a portion of the inflows from each event as environmental water to

meet target flows below Lake Brewster.

https://www.waternsw.com.au/__data/assets/pdf_file/0008/159803/Lachlan-Translucent-Environmental-Release-9-Aug-20.pdfhttps://www.waternsw.com.au/__data/assets/pdf_file/0008/159803/Lachlan-Translucent-Environmental-Release-9-Aug-20.pdf


• Licenced Environmental water release will follow at the same rate when the translucent flow at

Willandra weir cease on Tuesday

Water Availability

The DPIE WAS published on 4 September 2020, confirmed that an initial allocation of 28 percent

has been made to general security licence holders.

• There has also been commensurate increase in Conveyance allocation, in accordance with the

water sharing plan. In addition, all temporary water restrictions have been lifted, enabling full

access to GS water in accounts.

• 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.

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

WaterNSW website.

• Supplementary and Uncontrolled flows in Belubula are continued to be available for access.

Water Quality

• The Latest BGA samples show that the Lake Cargelligo Boatshed, Lake Cargelligo TWS, Lake

Cargelligo Outlet and Lake Cargelligo intake downstream of Curlew Water are on Green Alert

Level.

• The Wyangala Storage results (on 18 August 2020) ) show that productivity is now low at all sites.

Few cyanobacteria were observed, only a Microcystis sp. detection noted at the Inland Waters

Park. Assemblage is dominated by diatoms and green alga. Downstream showed no

cyanobacteria were detected. The storage is now at Green alert level.

• 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.


• Booberoi Ck desilting work is now finished and the flows are being diverted into the creek from

the offtake.

https://www.waternsw.com.au/__data/assets/pdf_file/0006/159036/Belubula-Operations-Update-1-July-20.pdfhttps://www.waternsw.com.au/__data/assets/pdf_file/0006/159036/Belubula-Operations-Update-1-July-20.pdf


5.2 Macquarie valley


• Burrendong Dam is at 44.8 percent of active capacity and currently releasing

approximately 2,000 ML/d for translucent flows. Releases are forecast to remain

between 1,000 – 1,700 ML/d depending on the inflows to the dam.

• Windamere Dam is currently at 29 percent of active capacity (107 GL) and releasing 10 ML/d.

Releases are forecast to stay at approximately 10 ML/d during this week.

• The recent storms and isolated stream flows have delayed 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 water in both active and translucent accounts is available.

• Translucent environmental water delivery from Burrendong Dam restarted from 31 August 2020

and is ongoing. The downstream tributary flows are receding.

• 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.

Water availability

• The WAS published by DPIE on 8 September 2020 confirmed that an initial allocation of 12

percent AWD has been made to GS licence holders and Improve the Macquarie Drought Stage

from Drought Stage 2 to Drought Stage 1.

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

• The temporary water restriction on Macquarie GS and EWA water accounts is lifted.

• 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 within 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 has gained approximately 27,000 ML so far this month.


• 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 from the recent rainfall events and contributions from

downstream tributaries.


Water quality

• Results for the 18th August showed few cyanobacteria detected across the reservoir. Minor counts

were observed in the Mookerawa and Cudgegong arms, but no potentially toxic species were

detected. Green and flood alga are present in low numbers suggesting current low productivity.

No cyanobacteria were detected downstream. Storage remains at Green Alert Level.

• Results for 5 August 2020 show that the Microcystis sp. bloom has declined. The storage continues

to show elevated productivity but is now dominated by green alga. Downstream showed a minor

Dolichospermum sp. detection. Windamere Dam is now at Green Alert Level.

• Works to reinstate the temperature curtain at Burrendong Dam have been done. The curtain is

now operational and is currently 10m below the surface, d/s temperatures are being monitored.


• Nil.


6. Northern valley based operational activities

6.1 Namoi valley

Storage, release and inflow status

• Split Rock Dam is at 4.9 percent of active capacity and is currently

releasing 12 ML/d.

• Keepit Dam is at 24.8 percent of active capacity and releases have ceased.

• Chaffey Dam is at 25.9 percent of active capacity and is currently releasing 5 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.


• 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 have recommenced as the dam

has risen above the 20 percent trigger in the Chaffey pipeline authorisation.

Water availability

• The WAS, published by DPIE (dated 6 August 2020) confirmed that in the Peel Valley LWU and

D&S allocation are 70 percent; HS and its sub-categories are 50 percent, and GS is zero percent.

• Current resource deficit for current commitments in the Peel Valley is 10.6 GL

• The latest Water Allocation Statement, published by DPIE (dated 8 September 2020) confirmed

resource improvements high enough to warrant increase in allocations in the Upper Namoi

Valley: local water utility and D&S have 100 percent, while HS has received additional 10

percent (100 percent total) allocation and the GS 50 percent allocation. Approximately 39

percent of the GS has been carried over into 2020-21 Water Year.

• Lower Namoi local water utility and D&S have 100 percent while HS has received additional 10

percent (100 percent total) allocation and GS has received 4.2 percent. The restrictions on

access to carryover have been repealed and this volume is equivalent to approximately 6

percent of total GS share components.


• The Peel Valley is in Drought Stage 3, downgraded from 4. 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 very low environmental flows of 3 ML/d.

• The Upper Namoi Valley is at Drought Stage 2. Releases recommenced on 30 March 2020 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

https://www.waternsw.com.au/supply/regional-nsw/operations-updateshttps://www.industry.nsw.gov.au/__data/assets/pdf_file/0004/317875/WAS-peel-20200806.pdfhttps://www.industry.nsw.gov.au/__data/assets/pdf_file/0008/321659/WAS-namoi-20200908.pdf


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 3 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 Valley until further inflows occur.

Water quality

• Split Rock Dam is on Green Alert Level in the storage;

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

• Chaffey Dam is on Green Alert Level in the storage.


• Mollee Fishway is currently unavailable due to infrastructure failure.


6.2 Gwydir valley


• Copeton Dam is at 16 percent of active capacity and is currently releasing 21

ML/d.


• No environmental flow orders are currently in place.

Water availability

• The latest Water Allocation Statement published by DPIE -Water (dated 7 September 2020)

confirmed an increase of 3.07 per cent for general security water users in the Gwydir (in total it is

at 4.77 percent of the entitlement).

• 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.

Water quality

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

in the storage.


• The Gwydir Valley 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. Please see the 1 July 2020 Operations Update for Gwydir Operations Update section of

the WaterNSW website.

• Planned supply interruptions

• No supply interruptions are expected.

https://www.industry.nsw.gov.au/__data/assets/pdf_file/0003/321528/WAS-Gwydir-20200907.pdfhttps://www.waternsw.com.au/__data/assets/pdf_file/0008/145286/Operations-Update-Gwydir-1-July.pdfhttps://www.waternsw.com.au/__data/assets/pdf_file/0008/145286/Operations-Update-Gwydir-1-July.pdf


6.3 Border rivers


• Pindari Dam is at 17 percent of capacity. Pindari low level valve

maintenance work has been completed and transparent releases have

resumed.

• Glenlyon Dam is at 14.6 percent of capacity and releases have ceased.

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

• Continued rainfall since February 2020 had generated significant flows across the Northern

valleys. The catchment is wet now and responses from further rainfall will be faster.

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


• There are no current additional releases for Environmental Water orders.

Water availability

• The latest WAS, published by DPIE -Water (dated 21 August 2020) confirmed 6.9 percent

allocation for General Security A in the NSW Border Rivers regulated water source that totals 14.2

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.


• The Border River is in Drought Stage 2. Customers are advised that if dry conditions persist, future

deliveries, including essential supplies, will be grouped together (as block releases) and where

possible with tributary flows, to improve delivery efficiency.

Water quality

• Recent Blue Green Algae (BGA) sampling at Pindari shows an Amber Alert Level.


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

https://www.waternsw.com.au/supply/regional-nsw/operations-updateshttps://www.industry.nsw.gov.au/__data/assets/pdf_file/0005/320000/WAS-Border-Rivers-20200821.pdfhttps://www.industry.nsw.gov.au/water/allocations-availability/droughts-floods/update/critical-valleys-in-drought


6.4 Barwon-Darling River system

River flow status

• The 2020 Northern Basin inflow event provided significant inflow to the

Barwon Darling system. 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 2020 and contributed approximately 695 GL inflow at Wilcannia.

• Currently Barwon-Darling system is receiving some inflows from Macquarie and Bogan rivers for

which access is available to the management zones downstream of Boorooma. Access

availability is forecast to drop below A class for all zones by the end of September 2020 unless

there is further rainfall.


• Planned Environmental Water (PEW) is water in the system that is below the Commence to Pump

conditions for access licences.

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.

• Flow has resumed between Mungindi and Wilcannia and access is allowed, as per licence

conditions, for customers for all management zones.

• 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 WaterInsights

Portal for recent flow class announcements.


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

https://www.industry.nsw.gov.au/__data/assets/pdf_file/0015/313035/WAS-Unregulated-River-20200701.pdfhttps://waterinsights.waternsw.com.au/16001-barwon-darling-unregulated-river/flow-classhttps://waterinsights.waternsw.com.au/16001-barwon-darling-unregulated-river/flow-classhttps://www.industry.nsw.gov.au/water/allocations-availability/droughts-floods/update/critical-valleys-in-droughthttps://www.industry.nsw.gov.au/water/allocations-availability/droughts-floods/update/critical-valleys-in-droughthttps://www.industry.nsw.gov.au/water/allocations-availability/droughts-floods/update/critical-valleys-in-drought


WaterNSW HYPLOT V134 Output 08/09/2020

Period 9 Month 01/01/2020 to 01/10/2020 2020416001 BARWON R @ MUNGINDI 141.0012 Hour Mean Discharge (ML/d) CP

416050 BARWON U/S PRESBURY 141.0012 Hour Mean Discharge (ML/d) CP

422004 BARWON @ MOGIL MOGIL 141.0012 Hour Mean Discharge (ML/d) CP

422003 BARWON @COLLARENEBRI 141.0012 Hour Mean Discharge (ML/d) CP

422025 BARWON @ TARA 141.0012 Hour Mean Discharge (ML/d) CP

422001 BARWON @ DANGAR BDGE 141.0012 Hour Mean Discharge (ML/d) CP

422026 BARWON @ BOOROOMA 141.0012 Hour Mean Discharge (ML/d) CP

422027 BARWON @ GEERA 141.0012 Hour Mean Discharge (ML/d) CP

036007200

108001440018000

036007200

108001440018000

036007200

108001440018000

036007200

108001440018000

036007200

108001440018000

036007200

108001440018000

036007200

108001440018000

036007200

108001440018000

Jan Feb Mar Apr May Jun Jul Aug Sep

WaterNSW HYPLOT V134 Output 15/09/2020Period 9 Month 01/01/2020 to 01/10/2020 2020

422002 BARWON @ BREWARRINA 141.00 12 Hour Mean Discharge (ML/d) CP

422028 BARWON @ BEEMERY 141.00 12 Hour Mean Discharge (ML/d) CP

425039 DARLING@WARRAWEENA 141.00 12 Hour Mean Discharge (ML/d) CP

425003 DARLING@BOURKE TOWN 141.00 12 Hour Mean Discharge (ML/d) CP

425004 DARLING@LOUTH 141.00 12 Hour Mean Discharge (ML/d) CP

425900 DARLING@TILPA 141.00 12 Hour Mean Discharge (ML/d) CP

425008 DARLING@WILC. MAIN C 141.00 12 Hour Mean Discharge (ML/d) CP

0

3600

7200

10800

14400

18000

0

3600

7200

10800

14400

18000

0

3600

7200

10800

14400

18000

0

3600

7200

10800

14400

18000

0

3600

7200

10800

14400

18000

0

3600

7200

10800

14400

18000

0

3600

7200

10800

14400

18000

Jan Feb Mar Apr May Jun Jul Aug Sep


7. Coastal valley based operational activities

7.1 Bega river


• Brogo Dam is at 101 percent of capacity and spilling.


• 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 and Uncontrolled flows are still continuing.


• The Bega/Brogo Regulated River water source is assessed to be in normal conditions now,

improved from Drought Stage 4 to Drought Stage 1.

• WaterNSW held an online River Operations Stakeholder Consultation Committee (ROSCCo)

meeting on 9 Sept 2020 and provided the operational updates to the group.

Water quality

• Recent BGA sampling at Brogo (1 Sept 2020) ) showed very low productivity across the

storage. No cyanobacteria were observed either upstream or downstream. The

assemblage is dominated by small counts of green alga. Storage remains on green

alert.

Planned supply interruptions

• Nil.


7.2 Hunter valley


• Glenbawn Dam is currently at 46 percent of capacity and is releases are

back to minimum, only release around 2 ML/d. Releases are forecast to

remain in steady, while the downstream demand is met by downstream tributary flows.

• Glennies Creek Dam is at 39.5 percent of capacity and releases are currently at minimum

release of 20 ML/d. Releases are forecast to remain in between 8-10 ML/d for rest of the week.

• Lostock Dam is at 100 percent of capacity.


• All environmental flow targets are being met by the tributary flows.

Water availability

• The recent WAS published by DPIE confirms that HS and GS licence categories have received

allocation increase.

• GS licenses in the Hunter Valley received an additional 23 percent allocation on 1 Aug 2020,

bringing the total AWD to 53 percent in this year. Carryover is equivalent to approximately 23

percent of the total share component. HS licences received an additional 10 percent allocation

bringing total AWD to 100 percent this year. All other categories received 100 percent

allocation.

• The EWA will be credited with 20 gigalitres (GL) in accordance with the Water Sharing Plan.

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


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

operations.

Water quality

• Recent BGA sampling at Glenbawn Dam shows that the Microcystis sp presence is continuing at

all upstream sites and is the dominant taxa. Densities at all monitoring locations appear to be in

decline. Downstream results also showed a minor Microcystis sp detection. Storage remains at

Amber Alert Level awaiting another clear result. However Green Alert Level is maintained at

Glennies Creek and Lostock Dams.


Nil


7.3 Toonumbar Dam


• Toonumbar Dam is at 67 percent of capacity and releasing approximately 8 ML/d. This release

may remain steady at 8 ML/d.


• No current additional operations.

Water availability

• All licence categories have 100 percent availability.

• WaterNSW held an online ROSCCo meeting on 24 June 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.


• The Drought Stage level has eased from Drought Stage 2 to Drought Stage 1 with normal

operations resuming.

Water quality

• Recent results for Toonumbar show that productivity is still reducing across the storage. Minor

counts of benign Cyanobacteria and green algae were noted. Small counts of Microcystis sp

were observed. A similar assemblage of Cyanobacteria was observed downstream. The storage

remains at Green Alert Level.


• Scheduled works to commence on 5 August 2020 for replacement of the 610” valve have been

cancelled, until further notice.


8. Rural Dam Levels

The following table shows the status of water supplies at 14 September 2020.

River Valley Active

Capacity Current Status

Weekly

change

(GL)

Comments

Likely-

hood of

fill and

spill

Allocations for 2020/21

Storage Dam, Nearest Town (GL)

percent of

active

capacity

Active

(GL)

Weekly

Change

(GL)

Supply Issues High

Security

Gen.

Security

C’over

avail @

1/7/20

Border Rivers

Glenlyon Dam, Stanthorpe

(Qld)

253 15% 37 0 Release ceased & good d/s tribs


1 Gigalitre (GL) = 1,000 Megalitres (ML) 1 ML = 1,000,000 litres

More information

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Documents

Regional water availability report · 8. Rural Dam Levels ... The total storage level of urban water supplies on 14 September 2020 was 95.3 percent of the total ... with the exception