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River Murray Weekly Report For the week ending Wednesday, 11 November 2020 Trim Ref: D20/46325 Rainfall and inflows Over the past week a low-pressure trough and associated thunderstorm activity produced moderate to heavy falls across parts of the northern Murray-Darling Basin (Map 1). In New South Wales light to moderate falls were mostly confined to areas along the Great Dividing Range, while in the southern Murray-Darling Basin the highest rainfall totals were over the upper Murrumbidgee and Lachlan River catchments. Map 1 - Murray-Darling Basin rainfall totals for week ending 11 November 2020 (Source: Bureau of Meteorology). Given the drier and warmer conditions across upper Murray catchments, upper Murray tributary inflows continued to ease this week. Further specific information about flows at key locations can be found at the MDBA’s River Subscribe to the River Murray Weekly Report River Data website Water in Storages

Rainfall and inflows - Murray-Darling Basin Authority · Web view2020/11/11  · level increased by 17 GL to 2,348 GL (61% capacity). The release, measured at Colemans, continued

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Page 1: Rainfall and inflows - Murray-Darling Basin Authority · Web view2020/11/11  · level increased by 17 GL to 2,348 GL (61% capacity). The release, measured at Colemans, continued

River Murray Weekly ReportFor the week ending Wednesday, 11 November 2020

Trim Ref: D20/46325

Rainfall and inflowsOver the past week a low-pressure trough and associated thunderstorm activity produced moderate to heavy falls across parts of the northern Murray-Darling Basin (Map 1). In New South Wales light to moderate falls were mostly confined to areas along the Great Dividing Range, while in the southern Murray-Darling Basin the highest rainfall totals were over the upper Murrumbidgee and Lachlan River catchments.

Map 1 - Murray-Darling Basin rainfall totals for week ending 11 November 2020 (Source: Bureau of Meteorology).

Given the drier and warmer conditions across upper Murray catchments, upper Murray tributary inflows continued to ease this week. Further specific information about flows at key locations can be found at the MDBA’s River Murray data webpage. Up-to-date river data for sites in the upper Murray can also be found on BoM’s website and in the Murray River Basin Daily River Report at the WaterNSW website. BoM produce 7-day stream flow forecasts for a number of tributaries including the Ovens and Kiewa Rivers and these are available on their website.

The Bureau of Meteorology’s (BoM) current 8 day rainfall forecast shows modest rain for the Basin, primarily in southern and eastern areas.

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Page 2: Rainfall and inflows - Murray-Darling Basin Authority · Web view2020/11/11  · level increased by 17 GL to 2,348 GL (61% capacity). The release, measured at Colemans, continued

River Murray Weekly Report

River operations

Water quality impactsAmber alerts for blue-green algae have been extended and now include the River Murray downstream of Yarrawonga Weir, Cobram, Picnic Point, Tooleybuc, Buronga and Lock 8, plus the Edward River at Old Morago and the Wakool River at Stoney Crossing. It is important that water users regularly keep up to date with algal alerts, notices and health warnings. This information is available through Goulburn-Murray Water and WaterNSW.

Following the Bureau of Metrology’s declaration of La Niña and continued wet rainfall outlook across south eastern Australia, Murray Darling Basin communities should be aware there is a significant risk of hypoxic blackwater events occurring particularly in New South Wales. After three hot and dry years, floodplains have a high load of leaf litter and other organic material. La Niña conditions in spring increase the risk of heavy rain and flooding, which can wash organic matter into waterways and lead to hypoxic blackwater events. For more information, including the Basin water quality risk map, please see the MDBA website.

Monthly snapshot of water in the systemRiver Murray communities can now access a monthly point-in-time snapshot that shows what proportion of water in the river has been provided for the environment compared with water for towns, industries and irrigators.

Every day, water enters the river at different points and for different purposes, including irrigation, town water supply, industries and specific environmental benefits. The monthly snapshot shows in simple terms the volume of flow and the extent to which it comprises water for the environment at five locations—in the River Murray at Yarrawonga and the South Australian border, and in the Murrumbidgee, Goulburn and Darling rivers just upstream of their junction with the Murray. Find out more on Flows in the River Murray system.

River operationsOver the past week, MDBA total active storage increased by 4 GL to 5,220 GL (62% capacity).

At Dartmouth Reservoir, the storage level increased by 17 GL to 2,348 GL (61% capacity). The release, measured at Colemans, continued to target the minimum flow rate of 200 ML/day.

After reaching a peak storage level late last week, this week the Hume Reservoir storage level decreased by 28 GL to 2,410 GL (80% capacity). The current Hume release is near 13,500 ML/day and is expected to increase in coming days as downstream tributary inflows further ease and demands slowly increase.

Currently, the majority of the Hume release is water for the environment, released to help meet a target flow rate downstream of Yarrawonga Weir. Over the coming weeks, should dry conditions prevail, MDBA may commence bulk transfers to slow the rate of storage decline at Lake Victoria. This operation would help ensure system demands can be met over the peak summer period. These transfers may include Hume to Lake Victoria transfers and call of water held in Inter Valley Trade accounts in the Goulburn and Murrumbidgee valleys. Further information will be provided in coming weeks.

At Lake Mulwala, the pool level remains near 124.74 m AHD and within the normal operating range of between 124.6 and 124.9 m AHD. Diversion to Mulwala Canal is currently 1,250 ML/day and on the Victorian side, about 1,200 ML/day is being diverted into Yarrawonga Main Channel. Diversions are anticipated to gradually increase over the coming week, in-line with the warm and mostly dry forecast conditions.

The release from Yarrawonga Weir has continued to target 15,000 ML/day and a similar rate is expected over the coming week. This release continues to support the Murray Cod nesting season, while also increasing lateral connectivity between the River Murray and the Barmah—Millewa Forest. This greater connectivity has been

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Hume Dam release increased to meet downstream demands Water for the environment supporting Murray Cod in the Murray and Lower Darling Lake Victoria storage level to peak in coming week System transfers to Lake Victoria may commence in coming weeks

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River Murray Weekly Report

enabled by the opening of selected regulators in the forest. Together, these actions promote increased productivity in the river and supports plants and animals in the forest. All actions associated with water for the environment are tracked and water usage debited from environmental water holder accounts.

Flow through the Edward River Offtake is steady near 1,540 ML/day, while flow through the Gulpa Creek Offtake continues to target 700 ML/day to help fill wetlands adjacent to the creek. Downstream return flows from Millewa forest to the Edward River continue and will persist over coming weeks. Flow through the Wakool River, Yallakool Creek and Colligen Creek offtakes is currently around 100, 500 and 400 ML/day, respectively. This week the flow downstream of Stevens Weir fluctuated around 2,400 ML/day and may ease this week if diversions to Wakool Main Canal increase above the current take of 580 ML/day.

On the Goulburn River, the flow measured at McCoys Bridge gradually reduced this week from around 1,500 ML/day to 1,100 ML/day. Later this week flows are anticipated to gradually increase and peak the following week, due to the release of water for the environment. This action is aimed at supporting large-scale Golden Perch migration and spawning in the Goulburn River. Information regarding opportunities for allocation trade between

the Goulburn and Murray Valleys is available at the Victorian water register website .

Diversions to National Channel increased to 2,100 ML/day and similar diversion is expected over the coming week to help improve storage levels in Kow Swamp and other mid-Murray lakes within the Torrumbarry Irrigation system.

Elevated baseflows continue to be supplied to Gunbower Creek to provide increased habitat for native fish and other aquatic animals over the spring period. Flow in Gunbower Creek returns to the River Murray via Koondrook Spillway, downstream of Torrumbarry Weir near Barham. This week the release downstream of Torrumbarry Weir reduced from around 9,750 ML/day to 8,100 ML/day.

Inflow from the Murrumbidgee River, measured at Balranald , averaged around 2,700 ML/day for the week. Flows are expected to increase to around 4,000 ML/day over the coming week, before receding. This higher flow is primarily due to the release of water for the environment from Burrinjuck Dam last month. For information on any supplementary access in the Murrumbidgee system, please refer

to the WaterNSW website . The Murrumbidgee IVT balance is open for trade from the Murray to the Murrumbidgee (102 GL) but remains closed for trade from the Murrumbidgee to the Murray.

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Photo 1 – Nardoo (Marsilea drummondii) that has grown in response to water for the environment being pumped (outlet in background) at Wallpolla Creek East; Wallpolla Island. Photo Credit: David Wood, MalleeCMA

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River Murray Weekly Report

At Euston Weir, the weir pool level remains at FSL. The downstream release peaked at around 15,500 ML/day before receding to the current flow of 13,500 ML/day and flows are expected to vary around this rate for the coming week.

Menindee Lakes storage eased this week to 438 GL (25% capacity). The downstream release, measured at Weir 32, remains near 480 ML/day, with small releases of water for the environment continuing to help boost the rate above the normal minimum target. These flows aim to improve the condition of the lower Darling and help Murray Cod breed this spring. For more information refer to the Commonwealth Environmental Water Office and NSW Department of Planning, Industry and Environment. Some water restrictions remain current in NSW. Links to drought services and assistance can be accessed via the MDBA drought webpage .

At Wentworth Weir, the weir pool level is being managed at around FSL. The downstream flow peaked at around 14,200 ML/day and is forecast to slowly decrease over the coming week.

Downstream at Lock 9, Lock 8 and Lock 7 weir pools continue to vary near FSL, within their normal operating range.

The storage level at Lake Victoria increased this week by 14 GL to 656 GL (97% capacity) as the storage continued capturing water in transit from upstream tributaries. The volume stored in Lake Victoria is forecast to continue to slowly rise over the coming week before falling in coming weeks and months under drier scenarios. No unregulated flows are currently forecast.

The flow to South Australia averaged around 9,900 ML/day and included the South Australian monthly Entitlement for November plus water for the environment and traded volumes. Over the coming days the flow is forecast to remain around 9,500 ML/day before increasing later in the week.

The Lower Lakes 5-day average water level is 0.82 m AHD. Increased barrage releases will continue to be made when conditions allow to push fresh water into the Coorong and to support Black Bream spawning over the coming months. For information on barrage releases and South Australia’s Entitlement flow, see the South Australian Department for Environment and Water Weekly River Murray Flow Report.

For media inquiries contact the Media Officer on 02 6279 0141

ANDREW REYNOLDSExecutive Director, River Management

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River Murray Weekly Report

Water in Storage Week ending Wednesday 11 Nov 2020

MDBA StoragesFull

Supply Level

Full Supply Volume

Current Storage Level

Current Storage Dead

StorageActive

Storage

Change in Total Storage for the

Week  (m AHD) (GL) (m AHD) (GL) % (GL) (GL) (GL)

Dartmouth Reservoir 486.00 3 856 459.47 2 348 61% 71 2 277 +17Hume Reservoir 192.00 3 005 188.85 2 410 80% 23 2 387 -28Lake Victoria 27.00 677 26.83 656 97% 100 556 +14Menindee Lakes   1 731*   438 25% (- -) # 0 -10Total   9 269   5 852 63% - - 5 220 -6Total Active MDBA Storage             62% ^  

                 

Major State StoragesBurrinjuck Reservoir   1 026   974 95% 3 971 +25Blowering Reservoir   1 631   1 412 87% 24 1 388 +17Eildon Reservoir   3 334   2 322 70% 100 2 222 +15

* Menindee surcharge capacity – 2050 GL ** All Data is rounded to nearest GL ** # NSW has sole access to water when the storage falls below 480 GL. MDBA regains access to water when the storage next reaches 640 GL.^ % of total active MDBA storage

Snowy Mountains Scheme Snowy diversions for week ending 10 Nov 2020

Storage Active Storage (GL) Weekly Change (GL) Diversion (GL) This Week From 1 May 2020

Lake Eucumbene - Total 1 412 +8 Snowy-Murray +8 467Snowy-Murray Component 686 +10 Tooma-Tumut +2 191Target Storage 1 450   Net Diversion 6 277

     Murray 1 Release +11 698

Major Diversions from Murray and Lower Darling (GL) *New South Wales This

Week From 1 July 2020 Victoria This Week From 1 July 2020

Murray Irrig. Ltd (Net) 12.0 209 Yarrawonga Main Channel (net) 6.8 50Wakool Sys Allowance 1.5 36 Torrumbarry System + Nyah (net) 9.7 89Western Murray Irrigation 0.6 4 Sunraysia Pumped Districts 2.6 18

Licensed Pumps n/a 61Licensed pumps - GMW (Nyah+u/s) n/a 4

Lower Darling n/a 0 Licensed pumps - LMW n/a 74TOTAL 14.1 310 TOTAL 19.1 235

* Figures are derived from actual and estimates where data is unavailable. Please note that not all data may have been available at the time of creating this report. ** All data above is rounded to nearest 100 ML for weekly data and nearest GL for cumulative data

Flow to South Australia (GL)* Flow to SA will be greater than normal entitlement for this month due to environmental flows.

Entitlement this month 180.0 *  Flow this week 69.4 (9 900 ML/day)Flow so far this month 109.5Flow last month 313.3

Salinity (EC) (microSiemens/cm at 25o C)

  Current Average over the last week Average since 1 August 2020

Swan Hill 80 80 110Euston - - -Red Cliffs 130 130 140Merbein 130 120 160Burtundy (Darling) 320 320 320Lock 9 130 130 140Lake Victoria 120 110 120Berri 180 180 160Waikerie 230 230 210Morgan 220 230 210Mannum 230 230 220

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River Murray Weekly Report

Murray Bridge 240 240 240Milang (Lake Alex.) 740 730 820Poltalloch (Lake Alex.) 420 510 480Meningie (Lake Alb.) 1 600 1 620 1 660Goolwa Barrages 880 900 1 290

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Page 7: Rainfall and inflows - Murray-Darling Basin Authority · Web view2020/11/11  · level increased by 17 GL to 2,348 GL (61% capacity). The release, measured at Colemans, continued

River Levels and Flows Week ending Wednesday 11 Nov 2020

 Minor Flood

Stage Gauge Height Flow Trend Average Flow this Week

Average Flow last Week

River Murray (m)local (m)

(m AHD) (ML/day)   (ML/day) (ML/day)

Khancoban - - - 1 700 F 1 940 4 530Jingellic 4.0 1.88 208.40 6 150 F 7 650 12 960Tallandoon ( Mitta Mitta River ) 4.2 1.61 218.50 1 050 F 1 150 1 410Heywoods 5.5 3.02 156.65 13 460 R 12 650 9 680Doctors Point 5.5 2.99 151.46 14 720 R 13 940 11 650Albury 4.3 2.00 149.44 - - - -Corowa 4.6 2.77 128.79 13 170 F 13 400 10 700Yarrawonga Weir (d/s) 6.4 2.25 117.29 15 050 F 15 110 15 070Tocumwal 6.4 2.87 106.71 15 280 S 15 210 15 240Torrumbarry Weir (d/s) 7.3 2.71 81.25 8 130 F 8 740 10 570Swan Hill 4.5 1.67 64.59 9 200 F 9 900 12 220Wakool Junction 8.8 3.85 52.97 12 110 F 12 950 14 210Euston Weir (d/s) 9.1 2.29 44.13 13 470 F 14 670 14 800Mildura Weir (d/s)   - - 14 190 F 14 810 14 440Wentworth Weir (d/s) 7.3 3.31 28.07 13 570 F 13 930 14 040Rufus Junction - 3.79 20.72 8 570 F 8 950 8 940Blanchetown (Lock 1 d/s) - 0.83 - 7 710 F 6 930 8 950               Tributaries              Kiewa at Bandiana 2.8 1.63 154.86 1 370 F 1 700 2 360Ovens at Wangaratta 11.9 8.93 146.61 3 220 F 3 840 5 840Goulburn at McCoys Bridge 9.0 1.58 93.00 1 140 F 1 270 2 140Edward at Stevens Weir (d/s) 5.5 2.26 82.04 2 400 F 2 430 2 560Edward at Liewah - 2.95 58.33 2 450 R 2 320 1 830Wakool at Stoney Crossing - 1.58 55.08 870 R 760 640Murrumbidgee at Balranald 5.0 3.46 59.42 3 560 R 2 670 2 440Barwon at Mungindi 6.1 2.94 - 0 F 0 0Darling at Bourke 9.0 3.93 - 40 F 50 60Darling at Burtundy Rocks - 0.80 - 330 F 370 340               Natural Inflow to Hume           11 350 18 450

(i.e. Pre Dartmouth & Snowy Mountains scheme)

Weirs and Locks Pool levels above or below Full Supply Level (FSL)

Murray FSL (m AHD) u/s d/s  FSL (m AHD) u/s d/s

Yarrawonga 124.90 -0.16 - No. 7 Rufus River 22.10+0.1

2 +1.48No. 26 Torrumbarry 86.05

+0.00 - No. 6 Murtho 19.25

+0.06 +0.56

No. 15 Euston 47.60+0.0

1 - No. 5 Renmark 16.30+0.4

2 +0.51

No. 11 Mildura 34.40+0.0

0 +0.50 No. 4 Bookpurnong 13.20+0.2

9 +0.91

No. 10 Wentworth 30.80+0.0

0 +0.67 No. 3 Overland Corner 9.80+0.0

3 +0.55

No. 9 Kulnine 27.40+0.0

3 +0.25 No. 2 Waikerie 6.10+0.2

1 +0.40

No. 8 Wangumma 24.60+0.0

8 +0.43 No. 1 Blanchetown 3.20+0.1

3 +0.08

Lower Lakes FSL = 0.75 m AHDLake Alexandrina average level for the past 5 days (m AHD) 0.82

Barrages Fishways at Barrages

  Openings Level (m AHD)No. Open Rock Ramp Vertical Slot 1

Vertical Slot 2 Dual Vertical Slots

Goolwa 128 openings 0.78 3 - Open Open -

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River Murray Weekly Report

Mundoo 26 openings 0.83All

closed - - - OpenHunters Creek - - - - Open - -Boundary Creek 6 openings - 1 - Open - -

Ewe Island 111 gates -All

closed - - - OpenTauwitchere 322 gates 0.80 4 Open Closed Open -

AHD = Level relative to Australian Height Datum, i.e. height above sea level

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Page 9: Rainfall and inflows - Murray-Darling Basin Authority · Web view2020/11/11  · level increased by 17 GL to 2,348 GL (61% capacity). The release, measured at Colemans, continued

Week ending Wednesday 11 Nov 2020

State Allocations (as at 11 Nov 2020)NSW - Murray Valley Victorian - Murray Valley

High security 97%General security 36%

High reliability 77%Low reliability 0%

NSW – Murrumbidgee Valley Victorian - Goulburn ValleyHigh security 95%General security 66%

High reliability 93%Low reliability 0%

NSW - Lower Darling South Australia – Murray ValleyHigh security 100%General security 30%

High security 100%

NSW : https://www.industry.nsw.gov.au/water/allocations-availability/allocations/summaryVIC : http://nvrm.net.au/seasonal-determinations/currentSA : https://www.environment.sa.gov.au/topics/river-murray/water-allocations-and-announcements

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