River Murray weekly report
For the week ending Wednesday, 06 April2018
Trim Ref:D16/13532
Rainfall and inflows
It was quite dry across the Murray-Darling Basin this week. There was little rainfall of any note, and most areas remained completely dry (Map 1). Temperatures stayed unseasonably warm for many parts of the Basin. However, a cold front that is currently moving slowly into the region from the west brings the promise of cooler weather for the week ahead, although little worthwhile rainfall is expected.
Map 1- Murray-Darling Basin rainfall week ending 30th March 2016 (Source: Bureau of Meteorology)
Flows along upper Murray tributaries are currently very low due to the recent lack of rain and limited catchment moisture. Most of the smaller tributaries are providing only a trickling inflow, while flows along the main tributaries have receded to base flow rates. For example, flows along both the upper Mitta Mitta River and the Ovens River have averaged less than 200 ML/day at most gauges.
March 2016 Summary
Weather conditions across the Murray-Darling Basin during March were dominated by record-breaking warmth. The Bureau of Meteorology (BoM) has reported that both Victoria and NSW recorded their highest ever mean temperature anomaly for March, with heat wave conditions experienced during the first half of the month. Mean monthly minimum temperatures were of particular note. ‘Very much above average’ minimum temperatures were widespread, with ‘highest on record’ minimum temperatures affecting areas in the north and south of the Basin (Map 2).
Map 2 - Minimum temperature deciles across Australia for March 2016 (Source: Bureau of Meteorology).
Monthly rainfall totals varied across the Basin relative to long-term averages; although for the most part, totals were average to below average. The dry conditions also took place on the back of mostly low rainfall during February. The exception was in far western areas, where above average to ‘very much above average’ rainfall was recorded (Map 3). This rain fell mostly during the middle of the monthwhen a significant rain event of tropical origin lingered over central Australia.
Across the Basin as a whole, the Bureau of Meteorology has reported area-averaged rain for March totalling 21.9 mm. The total was 43% below the long-term monthly mean and it was the 35th driest March observed during the past 117 years of record.
Map 3 - Murray-Darling Basin rainfall deciles for March 2016 (Source: Bureau of Meteorology)
River Murray System inflows during March (excluding Snowy Scheme, Darling River and managed environmental inflows) continued to decrease. The monthly total of around 60 GL was also well below the month’s long-term average of just over 200 GL. In comparison with the historical record since 1891, only about 6% of previous Marches have recorded lower inflows than March 2016.
Estimated evaporation losses from MDBA storages for March 2016 are reported in Table 1. Evaporation is estimated by multiplying the surface area of the storage by the net evaporation. Net evaporation is derived by subtracting the rainfall recorded at the storage from this calculated evaporation. Evaporative losses were relatively high in March due to above average temperatures across the region. However, in comparison with February, percentage evaporative losses were lower at Dartmouth Reservoir, Hume Reservoir and the Menindee Lakes. This would be expected when moving into the cooler and shorter days of autumn. March evaporative losses at Lake Victoria also decreased compared toFebruary. However thepercentage loss actuallyincreasedat this storage,as its overall volume of water was considerably less.
Table 1: Monthly evaporation figures for MDBA storages
Storage / *Approximate (net) evaporative loss in March 2016 (GL) / Average storage volume in March 2016 (GL) / Percentage evaporative loss in March 2016Dartmouth / 3 / 1697 / 0.2
Hume / 10 / 879 / 1.2
Lake Victoria / 15 / 303 / 5.0
Menindee Lakes / 4 / 52 / 7.6
*Evaporative loss from storage = surface area of the storage x net evaporation. Net evaporation = measured evaporation (using a ‘pan’ instrument) - rainfall.
River operations
Red alerts for blue-green algae continue along reaches from Hume Reservoir downstream to Murrabit and on the Edward-Wakool the red alert extends to Moulamein. The alerts apply to the main channel of the river as well as many anabranches and connected lakes and wetlands. More information is available from Goulburn Murray Water and NSW DPIas well as the MDBA website.
A significant break down in blue-green algae may still be several weeks away and will require a reduction in water temperatures and a change to weather conditions over the Murray valley that are less favourable to algal blooms such as decreased sunshine, increased wind andrainfall.
MDBA total storage decreased by 76 GL this week, with the active storage now 2,453 GL (29% capacity).
At Dartmouth Reservoir, the storage volume decreased 3 GL to 1,680 GL (44% capacity). The release from Dartmouth, measured at Colemans, remains at 600 ML/day. A similar release rate is planned for the coming week.
At Hume Reservoir, the storage volume decreased by 64 GL to 721 GL (24% capacity). The storage is currently forecast to continue decreasing during the coming weeks and may be around 500 GL by the end of the current irrigation season in May if conditions remain dry. The release from Hume Reservoir has been reasonably steady for much of the last week and is currently targeting a flow at Doctors Point (downstream of the Kiewa River junction) of about 12,000 ML/day.
Diversions from Lake Mulwalacontinued at similar ratesto last week.Total diversion into the YarrawongaMain Channel and the Mulwala Canal averaged close to 4,300ML/day. The downstream release from Yarrawonga Weirwas reduced slightly this week as overall system demands downstream continued to decline. The current release is 7,000 ML/day. Downstream release requirements will remain under constant review during the coming weeks. Further release reductions are possible as we move towardsthe end of the irrigation season in May.
On the Edward-Wakool system, inflows from the Murray via the Edward River offtake have been averaging about 1,500 ML/day. However, to balance overall flow requirements between the Murray and Edward sides of the system, this flow is now planned for reduction. Flows around 1,100ML/day are expected later in the coming week. At the Gulpa Creek offtake, the inflow has eased slightly to a rate just under 300 ML/day. Downstream at Stevens Weir the release target has been reduced to 600ML/day, compared with a target of 1,000 ML/day just over a week ago.Diversions through the Wakool Main Canal have increased slightly and averaged 600 ML/day this week. Further downstream, flows along both the lower Edward and Wakool Rivers are slowly receding along most reaches (Figure1).
On the Goulburn River, the flow at McCoys Bridge has receded to a target just under 1,000ML/day following the recent delivery of environmental water with peak flow rates above 4,000ML/day. The current target includes an additional component of environmental water that is providing for flows a little above the Goulburn River’s normal end of system target for this time of year.
At Torrumbarry Weir, the downstream flow is steadily receding towards 4,000 ML/day. Flow rates between 3,500 and 4,000 ML/day are expected during the coming week. Diversions of about 2,900ML/day continue at National Channel.
Further downstream, inflows to the Murray from the lower Murrumbidgee River at Balranald continue to fall away following the completion of inter-valley trade (IVT) delivery in late March. Flow rates under 500 ML/day are expected during the coming week.
Figure 1 - Sheep and boaters enjoying a recent sunrise on the dusty banks of the Edward River downstream of Moulamein.
Photo, Will Lucardie, MDBA.
At Euston Weir, the flow peaked early in the week at8,700 ML/day and has since receded to the current rate of 6,900 ML/day. Flows under 4,000 ML/day are expected in about 10 days’ time. The weir pool level hasreducedto 47.51 m AHD, which is 9 cm below the full supply level (FSL). The level will be further reduced during the coming days to a target of47.40 m AHD, or 20 cm below FSL.This action is being undertaken as part of the on-going weir pool level variability trial.
On the Darling River system, small flows resulting from rainfall in the northern Basin during January are now receding at Wilcannia. Without further rainfall, this flow is expected to cease within a few weeks. Only about 4 GL will have flowed into theMenindee Lakesat the completion of this event.The storage volume this week remained steady at 53 GL (3% capacity).
At the confluence of the Darling and Murray Rivers at Wentworth, the flow is currently peaking at about 7,100 ML/day with the on-going arrival of additional environmental water originating from the Goulburn River. A steady recession is now expected during the coming weeks. The weir pool remains around 10cm above full supply level to assist water users on the Lower Darling arm of the weir pool.
At Lake Victoria, the storage volume decreased by 10 GL to 246 GL (36% capacity). The flow into South Australia averaged 7,200 ML/day and has been boosted by the on-going delivery of Goulburn River environmental water. However these flows are now being decreased and will continue decreasing during the coming week. Flows of about 5,100 ML/day are planned for one week’s time.
At the Lower Lakes, the 5-day average water level in Lake Alexandrina has remained steady at 0.55m AHD.Small releases are continuing through the Tauwitchere barrage and via the fishways.However large swells and high tides forecast over the coming weekend may force the closure of barrage gates to limit the reverse flow of seawater into Lake Alexandrina.
For media inquiries contact the Media Officeron 02 6279 0141
DAVID DREVERMAN
Executive Director, River Management
Water in Storage Week ending Wednesday 06 Apr 2016
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 / 444.32 / 1 680 / 44% / 71 / 1 609 / -3
Hume Reservoir / 192.00 / 3 005 / 176.06 / 721 / 24% / 23 / 698 / -64
Lake Victoria / 27.00 / 677 / 23.00 / 246 / 36% / 100 / 146 / -10
Menindee Lakes / 1 731* / 53 / 3% / (- -) # / 0 / -0
Total / 9 269 / 2 700 / 29% / - - / 2 453 / -76
Total Active MDBA Storage / 29% ^
Major State Storages
Burrinjuck Reservoir / 1 026 / 370 / 36% / 3 / 367 / -13
Blowering Reservoir / 1 631 / 660 / 40% / 24 / 636 / +24
Eildon Reservoir / 3 334 / 1 113 / 33% / 100 / 1 013 / -43
*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 05 Apr 2016
Storage / Active Storage (GL) / Weekly Change (GL) / Diversion (GL) / This Week / From 1 May 2015Lake Eucumbene - Total / 1 568 / -37 / Snowy-Murray / +8 / 655
Snowy-Murray Component / 811 / -10 / Tooma-Tumut / +1 / 166
Target Storage / 1 340 / Net Diversion / 7 / 489
Murray 1 Release / +8 / 852
Major Diversions from Murray and Lower Darling (GL) *
New South Wales / This Week / From 1 July 2015 / Victoria / This Week / From 1 July 2015Murray Irrig. Ltd (Net) / 21.6 / 389 / Yarrawonga Main Channel (net) / 10.8 / 224
Wakool Sys Allowance / 2.7 / 74 / Torrumbarry System + Nyah (net) / 18.8 / 446
Western Murray Irrigation / 0.3 / 19 / Sunraysia Pumped Districts / 1.4 / 100
Licensed Pumps / 5.8 / 179 / Licensed pumps - GMW (Nyah+u/s) / 1.6 / 39
Lower Darling / 0.2 / 9 / Licensed pumps - LMW / 2.4 / 267
TOTAL / 30.6 / 670 / TOTAL / 35 / 1076
* 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 the delivery of additional environmental water. / Entitlement this month / 135.0 *
Flow this week / 50.3 / (7 200 ML/day)
Flow so far this month / 42.5
Flow last month / 219.0
Salinity (EC) (microSiemens/cm at 25o C)
Current / Average over the last week / Average since 1 August 2015Swan Hill / 70 / 70 / 70
Euston / - / - / -
Red Cliffs / 100 / 100 / 120
Merbein / 100 / 100 / 120
Burtundy (Darling) / 1 630 / 1 650 / 1 240
Lock 9 / 110 / 110 / 130
Lake Victoria / 230 / 220 / 210
Berri / 200 / 200 / 210
Waikerie / 240 / 230 / 270
Morgan / 260 / 260 / 270
Mannum / 270 / 280 / 320
Murray Bridge / 310 / 310 / 340
Milang (Lake Alex.) / 870 / 890 / 800
Poltalloch (Lake Alex.) / 810 / 800 / 670
Meningie (Lake Alb.) / 2 210 / 2 210 / 2 100
Goolwa Barrages / 1 530 / 1 520 / 1 210
River Levels and Flows Week ending Wednesday 06 Apr 2016
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 / - / - / - / 1 760 / F / 1 160 / 3 160
Jingellic / 4.0 / 1.35 / 207.87 / 1 930 / R / 1 820 / 4 150
Tallandoon ( Mitta Mitta River ) / 4.2 / 1.48 / 218.37 / 690 / S / 710 / 1 820
Heywoods / 5.5 / 3.04 / 156.67 / 11 200 / S / 11 550 / 12 110
Doctors Point / 5.5 / 2.75 / 151.22 / 11 950 / S / 12 300 / 12 890
Albury / 4.3 / 1.77 / 149.21 / - / - / - / -
Corowa / 4.6 / 2.56 / 128.58 / 11 310 / F / 11 610 / 12 180
Yarrawonga Weir (d/s) / 6.4 / 1.25 / 116.29 / 6 980 / S / 7 210 / 7 940
Tocumwal / 6.4 / 1.84 / 105.68 / 7 330 / F / 7 710 / 8 400
Torrumbarry Weir (d/s) / 7.3 / 1.49 / 80.03 / 4 150 / F / 4 770 / 6 620
Swan Hill / 4.5 / 0.99 / 63.91 / 4 580 / F / 5 070 / 6 560
Wakool Junction / 8.8 / 2.47 / 51.59 / 5 710 / F / 6 610 / 7 300
Euston Weir (d/s) / 9.1 / 1.43 / 43.27 / 6 910 / F / 7 970 / 7 070
Mildura Weir (d/s) / - / - / 7 430 / F / 7 340 / 5 740
Wentworth Weir (d/s) / 7.3 / 2.96 / 27.72 / 7 080 / R / 6 600 / 5 280
Rufus Junction / - / 3.51 / 20.44 / 6 580 / R / 6 830 / 6 930
Blanchetown (Lock 1 d/s) / - / 0.66 / - / 4 950 / F / 5 180 / 4 660
Tributaries
Kiewa at Bandiana / 2.8 / 0.76 / 153.99 / 220 / S / 230 / 350
Ovens at Wangaratta / 11.9 / 7.73 / 145.41 / 160 / R / 190 / 240
Goulburn at McCoys Bridge / 9.0 / 1.48 / 92.90 / 940 / F / 1 240 / 2 230
Edward at Stevens Weir (d/s) / 5.5 / 0.79 / 80.57 / 570 / F / 700 / 890
Edward at Liewah / - / 1.42 / 56.80 / 790 / S / 820 / 1 050
Wakool at Stoney Crossing / - / 1.39 / 54.88 / 370 / R / 360 / 440
Murrumbidgee at Balranald / 5.0 / 1.22 / 57.18 / 820 / F / 1 160 / 1 630
Barwon at Mungindi / 6.1 / 3.18 / - / 50 / S / 60 / 50
Darling at Bourke / 9.0 / 3.97 / - / 20 / F / 30 / 50
Darling at Burtundy Rocks / - / 0.57 / - / 0 / F / 0 / 0
Natural Inflow to Hume / 1 270 / 650
(i.e. Pre Dartmouth & Snowy Mountains scheme)
Weirs and LocksPool levels above or below Full Supply Level (FSL)
Murray / FSL (m AHD) / u/s / d/s / FSL (m AHD) / u/s / d/sYarrawonga / 124.90 / -0.11 / - / No. 7 Rufus River / 22.10 / -0.19 / +1.22
No. 26 Torrumbarry / 86.05 / +0.00 / - / No. 6 Murtho / 19.25 / +0.02 / +0.13
No. 15 Euston / 47.60 / -0.09 / - / No. 5 Renmark / 16.30 / +0.05 / +0.18
No. 11 Mildura / 34.40 / +0.06 / +0.23 / No. 4 Bookpurnong / 13.20 / +0.04 / +0.85
No. 10 Wentworth / 30.80 / +0.10 / +0.32 / No. 3 Overland Corner / 9.80 / +0.13 / +0.28
No. 9 Kulnine / 27.40 / +0.00 / -0.35 / No. 2 Waikerie / 6.10 / +0.08 / +0.12
No. 8 Wangumma / 24.60 / -0.45 / +0.01 / No. 1 Blanchetown / 3.20 / -0.08 / -0.09
Lower LakesFSL = 0.75 m AHD
Lake Alexandrina average level for the past 5 days (m AHD) / 0.55Barrages Fishways at Barrages
Openings / Level (m AHD) / No. Open / Rock Ramp / Vertical Slot 1 / Vertical Slot 2 / Dual Vertical SlotsGoolwa / 128 openings / 0.48 / All closed / - / Open / Open / -
Mundoo / 26 openings / 0.49 / All closed / - / - / - / Open
Hunters Creek / - / - / - / - / Open / - / -
Boundary Creek / 6 openings / - / All closed / - / Open / - / -
Ewe Island / 111 gates / - / All closed / - / - / - / Open
Tauwitchere / 322 gates / 0.50 / 2 / Open / Open / Open / -
* Mundoo Barrage Dual vertical slots are currently under construction.
AHD = Level relative to Australian Height Datum, i.e. height above sea level
GPO Box 1801 Canberra ACT 2601Telephone: 02 6279 0100Facsimile: 02 6248 8053
Page 1 of 8
Email: Web: ABN 13679821382
Week ending Wednesday 06 Apr 2016
State Allocations (as at 06 Apr 2016)
NSW - Murray Valley / Victorian - Murray ValleyHigh security / 97%
General security / 23%
/ High reliability / 100%
Low reliability / 0%
NSW – MurrumbidgeeValley / Victorian- GoulburnValley
High security / 95%
General security / 37%
/ High reliability / 90%
Low reliability / 0%
NSW - Lower Darling / South Australia – MurrayValley
High security / 75%
General security / 0%
/ High security / 100%
NSW : /
VIC : /
SA : /
Page 1 of 9