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Subscribe to the River Murray Weekly Report River Data website Water in Storages River Murray Weekly Report For the week ending Wednesday, 29 July 2020 Trim Ref: D20/28516 Rainfall and inflows Across the week rainfall was influenced by several weather systems: west-south-westerly air mass; a trough and low-pressure system; and a deepening low along the NSW coast. Though the upper catchments received some rainfall, generally little to no rainfall occurred across much of the River Murray system (Map 1). Map 1 - Murray-Darling Basin rainfall totals for week ending 29 July 2020 (Source: Bureau of Meteorology) Stream flows in the upper and mid-Murray tributaries receded this week. 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.

River Murray Weekly Report · 7/29/2020  · River Murray Weekly Report Subscribe to the River Murray Weekly Report River Data website Water in Storages The Bureau of Meteorology

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Page 1: River Murray Weekly Report · 7/29/2020  · River Murray Weekly Report Subscribe to the River Murray Weekly Report River Data website Water in Storages The Bureau of Meteorology

Subscribe to the River Murray Weekly Report River Data website Water in Storages

River Murray Weekly Report For the week ending Wednesday, 29 July 2020

Trim Ref: D20/28516

Rainfall and inflows Across the week rainfall was influenced by several weather systems: west-south-westerly air mass; a trough and low-pressure system; and a deepening low along the NSW coast. Though the upper catchments received some rainfall, generally little to no rainfall occurred across much of the River Murray system (Map 1).

Map 1 - Murray-Darling Basin rainfall totals for week ending 29 July 2020 (Source: Bureau of Meteorology)

Stream flows in the upper and mid-Murray tributaries receded this week. 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.

Page 2: River Murray Weekly Report · 7/29/2020  · River Murray Weekly Report Subscribe to the River Murray Weekly Report River Data website Water in Storages The Bureau of Meteorology

River Murray Weekly Report

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The Bureau of Meteorology (BoM) is currently forecasting a small amount of rainfall over the southern Murray-Darling Basin in the coming 8 days and has also issued an outlook for August to October (Map 2). The BoM outlook is forecasting higher than median rainfall over the Basin during this period.

Map 2 – Chance of exceeding median rainfall from August to October 2020 (Source: Bureau of Meteorology)

River operations

Unregulated flow event Tributary inflows downstream of Hume Dam have resulted in continued elevated flows through the mid and lower Murray. Lake Victoria is at 93% capacity and in accordance with the requirements of the Lake Victoria Operating Strategy the MDBA has been actively slowing the rate of fill of the lake.

These conditions enabled the commencement of an unregulated flow period from 27 June 2020. For the Murray (excluding the lower Darling) the extension of unregulated conditions will be highly dependent upon future rainfall. For more information on the expected duration and the river reaches where unregulated flow currently applies, refer to supplementary announcements from WaterNSW.

• Dartmouth and Hume storages continue to rise • Tributary inflows downstream of Yarrawonga extend period of unregulated flow • Unregulated flow at the Lower Lakes boosts release to the Coorong

Page 3: River Murray Weekly Report · 7/29/2020  · River Murray Weekly Report Subscribe to the River Murray Weekly Report River Data website Water in Storages The Bureau of Meteorology

River Murray Weekly Report

Subscribe to the River Murray Weekly Report River Data website Water in Storages

River operations and the COVID-19 virus The MDBA is continuing to work with government partners and stakeholders during this challenging time. In response to the impact of COVID-19, the MDBA has enacted business continuity arrangements to ensure the continued operation of our business functions. River operations have been identified as a priority in this time as running the river is essential to supporting irrigation supply to agricultural industries.

We hope all our community members remain safe at this time. We encourage all river users to evaluate plans against government advice, social distancing and travel, and to support actions to limit the spread of COVID-19.

Water quality impacts An amber alert for blue-green algae remains current in the River Murray system at Buronga. 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.

Operations Over the past week, MDBA total active storage (Dartmouth, Hume and Lake Victoria) increased by 81 GL to 3,965 GL (50% capacity).

At Dartmouth Reservoir, the storage increased by 9 GL to 2,053 GL (53% capacity). During the week the power station operator (AGL) continued to release entitlement water from Dartmouth to generate electricity. The release rate targeted around 1,000 to 1,200 ML/day (measured at Colemans gauge) for much of the week, as compared with the 200 ML/day minimum release standard for this time of year.

Photo 1: Dartmouth Dam with wattle (Photo Courtesy Peter Liepkalns)

Page 4: River Murray Weekly Report · 7/29/2020  · River Murray Weekly Report Subscribe to the River Murray Weekly Report River Data website Water in Storages The Bureau of Meteorology

River Murray Weekly Report

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At Hume Reservoir, the storage increased by 76 GL to 1,477 GL (49% capacity). This includes around 40 GL released from Snowy Hydro’s Khancoban Pondage into the Murray River upstream of Bringenbrong. Hume storage is expected to rise in the coming weeks as unregulated tributary inflows and releases from Snowy Hydro continue. The release from Hume remains at the minimum flow rate of 600 ML/day as elevated inflows from the Kiewa and Ovens Rivers meet and exceed minimum flow requirements downstream at Yarrawonga.

Photo 2: Nariel River above Staceys Bridge (Photo Courtesy Hugo Bowman)

At Lake Mulwala, Murray Irrigation Limited (MIL) has diverted up to 2,500 ML/day this week in order to refill irrigation channels and make supplementary access available to customers. Goulburn-Murray Water also commenced diverting small volumes into Yarrawonga Main Canal in preparation for refilling of irrigation channels. In response to the increase in diversions and receding tributary inflows, the release downstream of Yarrawonga Weir was gradually reduced from 7,400 ML/day to 4,000 ML/day. In the coming week, the Yarrawonga release is expected to continue at relatively low flows unless further rainfall increases tributary inflow.

Corresponding with the reduction in the Yarrawonga release, a number of regulators were closed in the Barmah-Millewa Forest to manage river levels through the forest and river channel.

Accordingly, on the Edward River, flows returning from the Millewa Forest are gradually receding. Approximately 30 ML/day is passing through the Wakool offtake regulator, 230 ML/day through Yallakool Creek offtake and near 240 ML/day into Colligen Creek. At Stevens Weir, diversions to the Wakool Main Canal averaged around 1,070 ML/day and the release downstream of the weir averaged near 700 ML/day.

On the Goulburn River, the flow measured at McCoys Bridge increased from near 3,500 ML/day early in the week to the current rate of near 5,000 ML/day. Inflows from the Goulburn River to the Murray are forecast to gradually recede over the coming week. Allocation trade from the Goulburn to the Murray system is currently closed. Information regarding opportunities for allocation trade between the Goulburn and Murray Valleys is available at the Victorian water register website.

Page 5: River Murray Weekly Report · 7/29/2020  · River Murray Weekly Report Subscribe to the River Murray Weekly Report River Data website Water in Storages The Bureau of Meteorology

River Murray Weekly Report

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The level of the Torrumbarry Weir pool will recommence raising gradually towards Full Supply Level (FSL) in the coming days. Flow downstream of Torrumbarry Weir fell from around 12,300 ML/day to near 9,000 ML/day and is expected to continue to fall over the coming week. In line with ongoing unregulated conditions, diversions to National Channel have increased to around 1,400 ML/day.

Inflow from the Murrumbidgee River, measured at Balranald, gradually receded from 1,400 ML/day to 1,000 ML/day. Elevated flows at Balranald have resulted from rain further upstream over the past month. Flows are expected to steadily recede during August as the lower reaches of the Murrumbidgee River return to regulated conditions. The Murrumbidgee IVT balance is open for trade from the Murray to the Murrumbidgee (99.9 GL) but remains closed to trade from the Murrumbidgee to the Murray.

At Euston Weir, the weir pool level is planned to be gradually raised back to FSL in the coming weeks. The downstream release peaked near 15,500 ML/day this week and over the coming fortnight is anticipated to recede towards 7,000 ML/day.

This week the Menindee Lakes storage decreased by 3 GL to 465 GL (27% capacity). The storage level will continue to ease over the coming weeks with no significant inflows forecast. The downstream release, measured at Weir 32, averaged around 80 ML/day over the past week. Despite the rainfall and streamflow responses during recent months, in many parts of NSW drought conditions persist with extensive water restrictions still in place. Links to drought services and assistance can be also accessed via the MDBA drought webpage.

At Wentworth Weir, the weir pool level is being managed to target around FSL (30.80 m AHD) but is expected to vary 10 cm above and below this level as part of normal operations. The current downstream flow of 14,700 ML/day is close to a peak.

This week, the Lake Victoria storage volume remained steady at 630 GL (93% capacity). The storage level in Lake Victoria will continue to be managed over the coming weeks in accordance with the Lake Victoria Operating Strategy. The strategy aims to fill the storage as late as possible while also holding a steady level for as short a time as possible to minimise erosion and inundation impacts on sensitive foreshore vegetation and cultural heritage material.

The current flow to South Australia of 13,400 ML/day is well above July entitlement (3,500 ML/day) due to ongoing unregulated flows. During the coming week flow to South Australia will recede below 10,000 ML/day as additional water is captured in Lake Victoria.

The Lower Lakes 5-day average water level is currently 0.82 m AHD. The arrival of unregulated flows to the Lower Lakes has allowed around 88 GL to be released to the Coorong this week via Tauwitchere, Goolwa, Mundoo, Ewe Island and Boundary Creek Barrages. Increased barrage releases will continue to be made when conditions allow to target outcomes in the Coorong. 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 REYNOLDS Executive Director, River Management

Page 6: River Murray Weekly Report · 7/29/2020  · River Murray Weekly Report Subscribe to the River Murray Weekly Report River Data website Water in Storages The Bureau of Meteorology

River Murray Weekly Report

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Water in Storage Week ending Wednesday 29 Jul 2020

MDBA Storages Full

Supply Level

Full Supply Volume

Current Storage

Level Current Storage Dead

Storage Active

Storage

Change in Total Storage for the

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

Dartmouth Reservoir 486.00 3 856 453.16 2 053 53% 71 1 982 +9 Hume Reservoir 192.00 3 005 182.78 1 477 49% 23 1 454 +76 Lake Victoria 27.00 677 26.60 629 93% 100 529 -1 Menindee Lakes 1 731* 465 27% (- -) # 0 -3 Total 9 269 4 624 50% - - 3 965 +81 Total Active MDBA Storage 47% ^ Major State Storages

Burrinjuck Reservoir 1 026 462 45% 3 459 +10 Blowering Reservoir 1 631 1 036 64% 24 1 012 +26 Eildon Reservoir 3 334 1 713 51% 100 1 613 +1

* 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 28 Jul 2020 Storage Active Storage (GL) Weekly Change (GL) Diversion (GL) This Week From 1 May 2020 Lake Eucumbene - Total 917 +2 Snowy-Murray +32 360 Snowy-Murray Component 376 -6 Tooma-Tumut +3 80 Target Storage 1 170 Net Diversion 29 280 Murray 1 Release +38 447

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) 17.8 59 Yarrawonga Main Channel (net) 1.2 1 Wakool Sys Allowance 3.4 13 Torrumbarry System + Nyah (net) 0 0 Western Murray Irrigation 0.1 0 Sunraysia Pumped Districts 0.8 2 Licensed Pumps 3.9 21 Licensed pumps - GMW (Nyah+u/s) n/a 1 Lower Darling 0.0 0 Licensed pumps - LMW 1.9 5 TOTAL 25.2 93 TOTAL 3.9 9

* 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 unregulated flows.

Entitlement this month 108.5 * Flow this week 91.7 (13 100 ML/day) Flow so far this month 331.7 Flow last month 104.7

Salinity (EC) (microSiemens/cm at 25o C) Current Average over the last week Average since 1 August 2019 Swan Hill 110 110 80 Euston - - - Red Cliffs 120 120 60 Merbein 130 130 100 Burtundy (Darling) 340 340 540 Lock 9 120 120 100 Lake Victoria 140 130 120 Berri 130 140 160 Waikerie 240 200 220 Morgan 220 190 230 Mannum 260 270 260 Murray Bridge 290 310 290 Milang (Lake Alex.) 990 980 910 Poltalloch (Lake Alex.) 400 460 780 Meningie (Lake Alb.) 1 730 1 710 1 800 Goolwa Barrages 2 130 2 890 3 140

Page 7: River Murray Weekly Report · 7/29/2020  · River Murray Weekly Report Subscribe to the River Murray Weekly Report River Data website Water in Storages The Bureau of Meteorology

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River Levels and Flows Week ending Wednesday 29 Jul 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 - - - 5 240 F 5 730 5 250 Jingellic 4.0 2.53 209.05 12 110 R 11 550 8 790 Tallandoon ( Mitta Mitta River ) 4.2 1.83 218.72 1 670 F 1 710 1 690 Heywoods 5.5 1.42 155.05 600 S 600 600 Doctors Point 5.5 1.62 150.09 1 840 R 2 220 2 490 Albury 4.3 0.79 148.23 - - - - Corowa 4.6 0.70 126.72 2 010 F 2 300 2 870 Yarrawonga Weir (d/s) 6.4 0.73 115.77 4 010 S 4 820 8 970 Tocumwal 6.4 1.26 105.10 3 890 F 5 410 9 110 Torrumbarry Weir (d/s) 7.3 2.93 81.48 9 000 R 10 050 13 400 Swan Hill 4.5 1.80 64.72 10 120 F 12 370 12 040 Wakool Junction 8.8 4.00 53.12 12 900 F 14 040 12 750 Euston Weir (d/s) 9.1 2.55 44.39 15 340 F 15 340 14 370 Mildura Weir (d/s) - - 15 290 F 14 860 14 170 Wentworth Weir (d/s) 7.3 3.45 28.21 14 680 S 14 390 13 860 Rufus Junction - 4.42 21.35 12 900 S 12 650 12 510 Blanchetown (Lock 1 d/s) - 1.06 - 13 090 R 12 900 14 340 Tributaries Kiewa at Bandiana 2.8 1.66 154.89 1 420 R 1 730 1 990 Ovens at Wangaratta 11.9 8.97 146.65 3 330 F 3 870 5 560 Goulburn at McCoys Bridge 9.0 3.79 95.21 5 550 F 4 490 6 770 Edward at Stevens Weir (d/s) 5.5 0.82 80.59 520 F 700 550 Edward at Liewah - 1.09 56.47 550 R 680 1 230 Wakool at Stoney Crossing - 1.44 54.93 520 S 540 480 Murrumbidgee at Balranald 5.0 1.36 57.32 950 F 1 130 1 910 Barwon at Mungindi 6.1 3.19 - 120 F 130 140 Darling at Bourke 9.0 3.99 - 60 F 60 100 Darling at Burtundy Rocks - 0.71 - 160 S 160 160 Natural Inflow to Hume 9 220 9 860

(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 -0.12 - No. 7 Rufus River 22.10 +0.04 +2.11 No. 26 Torrumbarry 86.05 -0.24 - No. 6 Murtho 19.25 +0.11 +0.55 No. 15 Euston 47.60 -0.30 - No. 5 Renmark 16.30 +0.11 +0.62 No. 11 Mildura 34.40 +0.01 +0.60 No. 4 Bookpurnong 13.20 +0.24 +1.24 No. 10 Wentworth 30.80 +0.00 +0.81 No. 3 Overland Corner 9.80 +0.00 +0.73 No. 9 Kulnine 27.40 +0.04 -0.04 No. 2 Waikerie 6.10 +0.14 +0.72 No. 8 Wangumma 24.60 -0.56 +0.61 No. 1 Blanchetown 3.20 +0.15 +0.31

Lower Lakes FSL = 0.75 m AHD Lake 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 0.85 4 - Open Open - Mundoo 26 openings 0.79 2 - - - Open Hunters Creek - - - - Open - - Boundary Creek 6 openings - 1 - Open - - Ewe Island 111 gates - 2 - - - Open Tauwitchere 322 gates 0.82 12 Open Open Open -

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

Page 8: River Murray Weekly Report · 7/29/2020  · River Murray Weekly Report Subscribe to the River Murray Weekly Report River Data website Water in Storages The Bureau of Meteorology

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Week ending Wednesday 29 Jul 2020

State Allocations (as at 29 Jul 2020)

NSW - Murray Valley Victorian - Murray Valley High security 97% General security 2%

High reliability 15% Low reliability 0%

NSW – Murrumbidgee Valley

Victorian - Goulburn Valley High security 95% General security 14%

High reliability 37% Low reliability 0%

NSW - Lower Darling

South Australia – Murray Valley High security 100% General security 30%

High security 77%

NSW : https://www.industry.nsw.gov.au/water/allocations-availability/allocations/summary

VIC : http://nvrm.net.au/seasonal-determinations/current

SA : https://www.environment.sa.gov.au/topics/river-murray/water-allocations-and-announcements