River Murray weekly report
For the week ending Wednesday, 11 January 2017
Trim Ref: D17/2011
Rainfall and inflows
A strong high pressure system in the Tasman Sea maintained hot and mostly dry conditions across most of the Murray-Darling Basin, before an extensive cloud band stretching from Western Australia brought rain to South Australia, areas of southern New South Wales and much of Victoria.
The heaviest falls were in the NSW and Victorian ranges, with 52 mm recorded at Thredbo AWS and 79 mm at Falls Creek AWS. In South Australia 34 mm fell at Mindarie in the Murray Mallee region.
Temperatures are expected to remain warm to hot along the Murray this week, with some rainfall forecast for Friday.
Map 1 - Murray-Darling Basin rainfall week ending 11 January 2017 (Source: Bureau of Meteorology)
Tributaries in the upper Murray catchments slowly receded this week before rainfall delivered short-lived rises. Hinnomunjie, on the Mitta Mitta River upstream of Dartmouth Reservoir, decreased to 550 ML/day before peaking near 1,700 ML/day. Similarly, Biggara on the upper Murray receded to 540 ML/day before peaking near 1,600 ML/day following Monday’s rain. The Kiewa River at Bandiana has fluctuated throughout the week, averaging near 1,300 ML/day, while the flow in the Ovens River at Wangaratta receded from 2,000 ML/day to below 1,300 ML/day before rising to 2,300 ML/day. Tributaries are expected to recede over the coming week.
River operations
MDBA total storage fell by 124 GL this week to 7,071 GL (82% capacity).
Dartmouth Reservoir storage increased by 8 GL to 3,014 GL (78% capacity). The release, measured at Colemans gauge, remained at 300 ML/day this week but is scheduled to be increased for three days starting on Friday 20 January 2017. This pulse of water is provided for by MDBA’s minimum release provisions for Dartmouth and is designed to mimic a small natural pulse that will provide water quality and ecosystem function benefits in the Mitta Mitta River downstream of Dartmouth Dam (see attached flow advice).
The storage volume at Hume Reservoir fell by 55 GL this week to 2,691 GL (90% capacity). Releases from Hume were increased to 15,800 ML/day during the week to help meet growing downstream demands before being gradually wound back to 11,800 ML/day. Downstream at Corowa, the flow has risen to 16,300 ML/day and is expected to gradually decline over the coming days.
This week’s hot weather contributed to higher than anticipated irrigation diversions (Photo 1) from Lake Mulwala. On the Victorian side, diversion to Yarrawonga Main Channel increased to near 1,600 ML/day before rain over Victorian irrigation districts eased demands back to 1,100 ML/day later in the week. Diversion to Mulwala Canal increased from 3,700 ML/day to 6,400 ML/day this week and is expected to increase further in the coming days. Currently, about 1,200 ML/day is being delivered via Mulwala Canal to the Edward River upstream of Deniliquin to supply customers on the Wakool Main Canal, where demand increased to around 1,700 ML/day. Given the higher than anticipated diversions from Lake Mulwala, the pool level dipped to 124.69 m AHD before additional water released from Hume increased the pool level.
Releases from Yarrawonga Weir have remained around 8,000 ML/day this week and are expected to average near this rate over the coming weeks. These releases are lower than experienced over the last few years at this time of year due to downstream demands being supplemented by water from the Goulburn, Campaspe, Murrumbidgee and Menindee Lakes. This allows more water to be conserved in the major storages of Hume and Dartmouth than would otherwise have been the case.
On the Edward River system, the flow through the Edward and Gulpa offtakes has remained near 1,600 ML/day and 500 ML/day, respectively. Downstream at Stevens Weir the flow is 600 ML/day and is expected to remain near this rate over the coming week.
The flow in the Goulburn River at McCoys Bridge fluctuated this week, falling from 2,900 to 2,000 ML/day before rising to 3,000 ML/day. The flow is expected to recede to around 1,500 ML/day in the next few weeks. Dissolved oxygen readings in the lower Goulburn dropped to near 1 mg/L (hypoxic) at the start of the week before recovering in the following days. No notable change in dissolved oxygen has been recorded in the Murray from this event.
Inter Valley Trade (IVT) deliveries from the Goulburn and Broken Creek to the Murray have now begun, and deliveries from the Campaspe are to begin shortly. These deliveries are expected to persist for the next few months and will help meet downstream demands in the Murray system. Once sufficient volumes have been delivered to the Murray, trade out of the Goulburn, Campaspe, Broken and Loddon system may be made available.
Photo 1 – This week’s hot temperatures helped drive up irrigation demands in the Riverina.
At Torrumbarry Weir, the diversion to National Channel has remained steady around 2,300 ML/day. This includes a small component of environmental water to maintain higher flows in Gunbower Creek for juvenile Murray Cod development. The majority of this environmental flow will return to the River Murray upstream of Barham and will be used to help meet downstream demands. The release from the weir increased to 7,500 earlier in the week before receding to 6,400 ML/day.
On the lower Murrumbidgee River, the flow at Balranald receded further, falling from 4,100 ML/day to near 600 ML/day. IVT deliveries from the Murrumbidgee system are to begin in about 3 weeks’ time and may persist beyond February. This will result in the flow at Balranald increasing to around 2,000 ML/day. Once a sufficient volume of IVT has been delivered from the Murrumbidgee to the Murray, trade out of the Murrumbidgee may become available. Further information on IVT in the Murrumbidgee system is available from WaterNSW.
Downstream on the Murray at Euston, the flow receded from 16,500 ML/day to 12,000 ML/day. The flow is expected to further recede over the coming week. The lock at Euston is closed due to repair works being undertaken on one of the upstream lock gates (see attached media release). In the coming weeks the Euston weir pool may be lowered below the Full Supply Level (FSL) but will be returned to near FSL during important recreational times.
Photo 2 – An inundated wetland surrounded by Redgum Forest in Gulpa Island, Millewa Forest. Source: Sarah Commens, MDBA.
Total storage in Menindee Lakes reduced by 54 GL this week and is now 1,454 GL (82% capacity). Releases, measured at Weir 32, had averaged around 1,800 ML/day for around three weeks. A portion of this release was environmental water aimed at supporting the growth and dispersal of Murray Cod that have spawned in the Lower Darling River over the past few months. However this week the release changed to an operational release to begin supplying water to the River Murray System. The operational release has been shaped to mimic a more natural pulse to benefit native fish in the lower Darling. Releases have increased to 4,600 ML/day this week and will increase to 6,500 ML/day in the coming days before being gradually returned to a steady flow of 5,000 ML/day later in January. Releases will continue as needed until the end of the irrigation season. Even without further flows past Wilcannia, MDBA is not expecting the total volume in the Lakes to fall below about 600 GL by the end of May.
On the Murray, weir pools at Locks 9, 8 and 7 are currently close to Full Supply Level (FSL) but are planned to be lowered below FSL in the coming weeks. Weir pool variability helps to restore a more natural wetting and drying cycle to riverbanks along weir pool affected reaches. More information on possible weir pool levels in the coming weeks is available on the MDBA website.
The Lake Victoria storage volume reduced by 24 GL this week 586 GL (87% capacity) and is forecast to continue decreasing over coming months if conditions are dry. Currently water in Lake Victoria is supplementing Murray flows to target a flow to South Australia of 17,000 ML/day. This flow rate will be gradually reduced throughout the remainder of this month.
At the Lower Lakes, the 5-day average level in Lake Alexandrina is 0.80 m AHD. As the flooding subsides in South Australia, barrage releases have fallen from over 70,000 ML/day last week to below 10,000 ML/day this week.
For media inquiries contact the Media Officer on 02 6279 0141
DAVID DREVERMAN
Executive Director, River Management
Water in Storage Week ending Wednesday 11 Jan 2017
(m AHD) / (GL) / (m AHD) / (GL) / % / (GL) / (GL) / (GL)
Dartmouth Reservoir / 486.00 / 3 856 / 472.18 / 3 014 / 78% / 71 / 2 943 / +8
Hume Reservoir / 192.00 / 3 005 / 190.39 / 2 691 / 90% / 23 / 2 668 / -55
Lake Victoria / 27.00 / 677 / 26.24 / 586 / 87% / 100 / 486 / -24
Menindee Lakes / 1 731* / 1 454 / 84% / (480 #) / 974 / -54
Total / 9 269 / 7 745 / 84% / - - / 7 071 / -124
Total Active MDBA Storage / 82% ^
Major State Storages
Burrinjuck Reservoir / 1 026 / 950 / 93% / 3 / 947 / -32
Blowering Reservoir / 1 631 / 1 485 / 91% / 24 / 1 461 / -59
Eildon Reservoir / 3 334 / 2 587 / 78% / 100 / 2 487 / -27
* 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 Jan 2017
Storage / Active Storage (GL) / Weekly Change (GL) / Diversion (GL) / This Week / From 1 May 2016Lake Eucumbene - Total / 1 929 / -21 / Snowy-Murray / +8 / 880
Snowy-Murray Component / 884 / -1 / Tooma-Tumut / +0 / 320
Target Storage / 1 520 / Net Diversion / 8 / 560
Murray 1 Release / +15 / 1 273
Major Diversions from Murray and Lower Darling (GL) *
New South Wales / This Week / From 1 July 2016 / Victoria / This Week / From 1 July 2016Murray Irrig. Ltd (Net) / 43.5 / 410 / Yarrawonga Main Channel (net) / 9.2 / 90
Wakool Sys Allowance / 1.7 / 1 / Torrumbarry System + Nyah (net) / 12.7 / 194
Western Murray Irrigation / 1.1 / 11 / Sunraysia Pumped Districts / 4.6 / 48
Licensed Pumps / 8.6 / 95 / Licensed pumps - GMW (Nyah+u/s) / 2.6 / 11
Lower Darling / 0.2 / 3 / Licensed pumps - LMW / 20 / 167
TOTAL / 55.1 / 520 / TOTAL / 49.1 / 510
* 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 trades and environmental deliveries. / Entitlement this month / 217.0 *
Flow this week / 120.2 / (17 200 ML/day)
Flow so far this month / 191.8
Flow last month / 1,915.3
Salinity (EC) (microSiemens/cm at 25o C)
Current / Average over the last week / Average since 1 August 2016Swan Hill / 110 / 100 / 130
Euston / - / - / -
Red Cliffs / 160 / 180 / 160
Merbein / 160 / 190 / 160
Burtundy (Darling) / 400 / 400 / 650
Lock 9 / 210 / 230 / 170
Lake Victoria / 190 / 190 / 180
Berri / 300 / 300 / 200
Waikerie / 460 / 520 / 260
Morgan / 510 / 590 / 260
Mannum / 600 / 540 / 260
Murray Bridge / 430 / 390 / 260
Milang (Lake Alex.) / 360 / 370 / 540
Poltalloch (Lake Alex.) / 380 / 380 / 320
Meningie (Lake Alb.) / 1 620 / 1 610 / 1 770
Goolwa Barrages / 430 / 480 / 1 230
River Levels and Flows Week ending Wednesday 11 Jan 2017
Minor Flood Stage / Gauge / Height / Flow / Trend / Average Flow this Week / Average Flow last WeekRiver Murray / (m) / local (m) / (m AHD) / (ML/day) / (ML/day) / (ML/day)
Khancoban / - / - / - / 1 930 / F / 2 820 / 3 130
Jingellic / 4.0 / 1.70 / 208.22 / 4 240 / R / 3 870 / 6 090
Tallandoon ( Mitta Mitta River ) / 4.2 / 1.60 / 218.49 / 1 020 / F / 970 / 1 200
Heywoods / 5.5 / 2.80 / 156.43 / 12 170 / F / 12 090 / 8 150
Doctors Point / 5.5 / 2.90 / 151.37 / 13 760 / F / 14 110 / 10 220
Albury / 4.3 / 1.86 / 149.30 / - / - / - / -
Corowa / 4.6 / 3.30 / 129.32 / 16 320 / R / 12 930 / 10 580
Yarrawonga Weir (d/s) / 6.4 / 1.35 / 116.39 / 7 910 / S / 8 030 / 9 750
Tocumwal / 6.4 / 2.20 / 106.04 / 9 860 / F / 9 940 / 11 940
Torrumbarry Weir (d/s) / 7.3 / 2.13 / 80.68 / 6 410 / F / 8 110 / 7 670
Swan Hill / 4.5 / 1.54 / 64.46 / 8 340 / F / 7 930 / 7 910
Wakool Junction / 8.8 / 3.60 / 52.72 / 10 840 / R / 6 990 / 8 940
Euston Weir (d/s) / 9.1 / 2.17 / 44.01 / 12 000 / F / 13 820 / 17 380
Mildura Weir (d/s) / - / - / 13 620 / F / 15 250 / 18 100
Wentworth Weir (d/s) / 7.3 / 3.41 / 28.17 / 13 340 / F / 14 710 / 17 650
Rufus Junction / - / 4.82 / 21.75 / 16 070 / R / 16 190 / 18 160
Blanchetown (Lock 1 d/s) / - / 1.42 / - / 18 400 / R / 18 610 / 56 890
Tributaries
Kiewa at Bandiana / 2.8 / 1.65 / 154.88 / 1 450 / R / 1 270 / 1 470
Ovens at Wangaratta / 11.9 / 8.68 / 146.36 / 2 340 / R / 1 570 / 2 960
Goulburn at McCoys Bridge / 9.0 / 2.59 / 94.01 / 3 020 / R / 2 510 / 2 160
Edward at Stevens Weir (d/s) / 5.5 / 0.84 / 80.61 / 610 / F / 610 / 980
Edward at Liewah / - / 1.73 / 57.11 / 1 040 / F / 1 200 / 1 500
Wakool at Stoney Crossing / - / 1.74 / 55.23 / 1 320 / F / 1 670 / 2 180
Murrumbidgee at Balranald / 5.0 / 0.97 / 56.93 / 580 / F / 1 790 / 5 590
Barwon at Mungindi / 6.1 / 3.16 / - / 30 / R / 10 / 90
Darling at Bourke / 9.0 / 4.06 / - / 220 / S / 290 / 420
Darling at Burtundy Rocks / - / 1.14 / - / 1 370 / S / 1 390 / 1 390
Natural Inflow to Hume / 4 980 / 8 830
(i.e. Pre Dartmouth & Snowy Mountains scheme)