Upload
others
View
6
Download
0
Embed Size (px)
Citation preview
River Murray Weekly Report
For the week ending Wednesday, 22 July 2020
Trim Ref: D20/25074
Rainfall and inflows
Conditions were mostly dry across the Murray-Darling Basin this week, with rainfall limited to the southern slopes and ranges (Map 1). The Bureau of Meteorology (BoM) is currently forecasting a small amount of rainfall over the southern Murray-Darling Basin in the coming 8 days.
Map 1 - Murray-Darling Basin rainfall totals for week ending 22 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 operations
· Storage in Dartmouth and Hume continues to rise.
· Tributary inflows downstream of Hume extend period of unregulated flow,
· Unregulated flow at the lower Lakes boosts release to the Coorong.
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 the MDBA is actively slowing the rate of fill of the lake in accordance with the requirements of the Lake Victoria Operating Strategy. There is sufficient surplus flow remaining to extend the period of unregulated flow that commenced on 27 June. For more information on the expected duration and the river reaches where unregulated flow currently applies, refer to supplementary announcements from WaterNSW.
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 88 GL to 3,881 GL (46% capacity).
At Dartmouth Reservoir, the storage increased by 12 GL to 2,044 GL (53% capacity). During the week the power station operator (AGL) continued to release entitlement water from Dartmouth for the purposes of electricity generation. The release rate targeted around 1,000 to 1,200 ML/day (measured at Colemans) for much of the week, compared with normal minimum releases for this time of year of 200 ML/day.
At Hume Reservoir, the storage increased by 76 GL to 1,401 GL (47% capacity). This includes around 37 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.
At Lake Mulwala, the diversion to Mulwala Canal reached around 3,000 ML/day as Murray Irrigation Limited (MIL) continued to refill their irrigation channels and make available supplementary access water to customers. Goulburn-Murray Water also commenced diverting small volumes to the Yarrawonga Main Canal in preparation for refilling their irrigation channels. In response to the increase in diversions and receding tributary inflows, the release downstream of Yarrawonga Weir was gradually reduced from 10,500 ML/day to 7,400 ML/day. The release is expected to continue to reduce over the coming week to below 6,000 ML/day.
Downstream in the Barmah - Millewa Forest, a number of regulators remained open to manage river levels through the Choke within the capacity of the river channel (ie a water level below 2.6 m on the local gauge at Picnic Point). However, with the release downstream of Yarrawonga reducing below 9,000 ML/day over the weekend, the forest regulators will be closed in the coming days (Note: a release of about 9,000 ML/day from Yarrawonga Weir is a proxy for the capacity of the river through the Choke when around 2,000 ML/day is diverted via the Edward-Wakool system, forest regulators are closed and there are low diversions for irrigation in the reach between Yarrawonga and Barmah).
Photo 1: Kiewa River East Branch (Photo Courtesy Hugo Bowman)
On the Edward River, return flows from the Murray via the Millewa Forest increased by around 200 ML/day late in the week. These return flows are expected to continue for another few days before reducing and finally ceasing in around two weeks following the closure of the forest regulators in the coming days. Diversions into the Wakool River, Yallakool and Colligen Creeks remain at levels sufficient to provide entitlement holders with access to unregulated flows. At Stevens Weir, diversions to the Wakool Main Canal were around 1,100 ML/day and the release downstream of the weir averaged 550 ML/day.
On the Goulburn River, the flow measured at McCoys Bridge peaked near 9,000 ML/day early in the week before reducing to the current rate of 4,000 ML/day. Inflows from the Goulburn to the Murray are forecast to remain around 3,000 to 5,000 ML/day 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.
The level of the Torrumbarry Weir pool continues to vary daily within the target range of 20-30 cm below Full Supply Level (FSL) as part of the weir pool variability program. Varying pool levels helps to reduce the incidence of notching and can help improve bank stability for riverbanks within the influence of the weir pool. Diversions to National Channel from the weir pool were steady at around 420 ML/day to maintain winter baseflows in the Gunbower Creek for the benefit of native fish. Around 200 ML/day of this flow returns to the River Murray downstream of Torrumbarry Weir near Barham Bridge, via Koondrook Spillway The additional loss arising from this watering action is debited against environmental water holders’ entitlements. In response to inflows from the Goulburn River, the downstream release from Torrumbarry Weir peaked during the week at 14,500 ML/day and is forecast to continue to steadily reduce over the coming week.
Inflow from the Murrumbidgee River, measured at Balranald, gradually receded from 2,400 ML/day to 1,400 ML/day. Elevated flows at Balranald have resulted from rain further upstream over the past month. Flows are expected to steadily recede over the remainder of July 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 continues to target around 30 cm below FSL as part of the weir pool variability program. The downstream release remained above 14,000 ML/day this week and is expected to reach around 15,000 ML/day in the coming week.
Photo 2: Upper Murrumbidgee River at Tharwa (Photo courtesy Andy Lowes)
This week the Menindee Lakes storage decreased by 4 GL to 468 GL (27% capacity). The storage level will continue to ease over the coming weeks with no significant inflows currently forecast. The downstream release, measured at Weir 32, averaged around 240 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
Photo 3: Lake Pamamaroo (Photo Courtesy Craig Symonds, WaterNSW)
Photo 4: View of Lake Wetherell from the Pamamaroo inlet regulator (Photo Courtesy Craig Symonds, WaterNSW)
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 downstream release averaged around 14,000 ML/day and is expected to remain around this rate over the coming week.
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 flow to South Australia averaged 12,900 ML/day this week, as unregulated flows continued across the border. Flow to South Australia will remain above normal Entitlement into August as high flows continue to arrive from upstream. For more information on South Australia’s Entitlement flow, see the South Australian Department for Environment and Water’s latest River Murray flow report.
The Lower Lakes 5-day average water level is currently 0.8 m AHD. The arrival of unregulated flows to the Lower Lakes has allowed around 65 GL to be released to the Coorong this week via Tauwitchere, Goolwa, Mundoo 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 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
Water in Storage Week ending Wednesday 22 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
452.95
2 044
53%
71
1 973
+12
Hume Reservoir
192.00
3 005
182.20
1 401
47%
23
1 378
+76
Lake Victoria
27.00
677
26.61
630
93%
100
530
-0
Menindee Lakes
1 731*
468
27%
(- -) #
0
-4
Total
9 269
4 543
49%
- -
3 881
+83
Total Active MDBA Storage
46% ^
Major State Storages
Burrinjuck Reservoir
1 026
453
44%
3
450
-2
Blowering Reservoir
1 631
1 010
62%
24
986
+32
Eildon Reservoir
3 334
1 713
51%
100
1 613
+24
* 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 21 Jul 2020
Storage
Active Storage (GL)
Weekly Change (GL)
Diversion (GL)
This Week
From 1 May 2020
Lake Eucumbene - Total
916
-8
Snowy-Murray
+23
328
Snowy-Murray Component
382
-17
Tooma-Tumut
+4
77
Target Storage
1 170
Net Diversion
19
251
Murray 1 Release
+30
409
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)
21.0
42
Yarrawonga Main Channel (net)
0.1
0
Wakool Sys Allowance
4.1
9
Torrumbarry System + Nyah (net)
0
0
Western Murray Irrigation
0.1
0
Sunraysia Pumped Districts
0.5
1
Licensed Pumps
n/a
18
Licensed pumps - GMW (Nyah+u/s)
0
0
Lower Darling
0.0
0
Licensed pumps - LMW
1.7
3
TOTAL
25.2
69
TOTAL
2.3
4
* 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 and environmental flows.
Entitlement this month
108.5 *
Flow this week
90.5
(12 900 ML/day)
Flow so far this month
239.9
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
120
100
Burtundy (Darling)
330
320
560
Lock 9
110
110
100
Lake Victoria
130
130
120
Berri
140
130
160
Waikerie
170
210
220
Morgan
210
230
230
Mannum
320
310
260
Murray Bridge
300
300
290
Milang (Lake Alex.)
970
960
900
Poltalloch (Lake Alex.)
500
480
780
Meningie (Lake Alb.)
1 670
1 690
1 800
Goolwa Barrages
4 050
3 810
3 150
River Murray Weekly Report
Subscribe to the River Murray Weekly Report River Data website Water in Storages
Subscribe to the River Murray Weekly Report River Data website Water in Storages
River Levels and Flows Week ending Wednesday 22 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
-
-
-
6 890
F
4 970
5 300
Jingellic
4.0
2.29
208.81
9 830
R
8 790
10 020
Tallandoon ( Mitta Mitta River )
4.2
1.86
218.75
1 760
F
1 690
2 130
Heywoods
5.5
1.44
155.07
600
S
600
600
Doctors Point
5.5
1.71
150.18
2 280
R
2 490
3 250
Albury
4.3
0.86
148.30
-
-
-
-
Corowa
4.6
0.79
126.81
2 270
F
2 870
3 280
Yarrawonga Weir (d/s)
6.4
1.25
116.29
7 410
R
8 970
9 310
Tocumwal
6.4
1.87
105.71
7 570
F
9 110
9 040
Torrumbarry Weir (d/s)
7.3
3.97
82.51
13 290
F
13 400
10 760
Swan Hill
4.5
2.34
65.26
13 520
R
12 040
10 900
Wakool Junction
8.8
4.12
53.24
13 520
R
12 750
12 700
Euston Weir (d/s)
9.1
2.46
44.30
14 730
R
14 370
14 960
Mildura Weir (d/s)
-
-
14 270
F
14 180
15 050
Wentworth Weir (d/s)
7.3
3.35
28.11
13 720
S
13 860
14 920
Rufus Junction
-
4.33
21.26
12 220
R
12 510
11 740
Blanchetown (Lock 1 d/s)
-
1.06
-
13 750
F
14 340
11 020
Tributaries
Kiewa at Bandiana
2.8
1.91
155.14
1 850
R
1 990
2 650
Ovens at Wangaratta
11.9
9.40
147.08
4 720
F
5 560
7 200
Goulburn at McCoys Bridge
9.0
3.09
94.51
4 020
F
6 770
4 990
Edward at Stevens Weir (d/s)
5.5
0.86
80.64
570
F
550
770
Edward at Liewah
-
1.69
57.07
1 020
F
1 230
1 080
Wakool at Stoney Crossing
-
1.45
54.94
550
R
480
290
Murrumbidgee at Balranald
5.0
1.82
57.78
1 400
F
1 910
2 180
Barwon at Mungindi
6.1
3.21
-
140
F
140
200
Darling at Bourke
9.0
4.01
-
90
F
100
50
Darling at Burtundy Rocks
-
0.71
-
160
S
160
170
Natural Inflow to Hume
9 710
10 730
(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
-0.18
-
No. 7 Rufus River
22.10
+0.01
+2.01
No. 26 Torrumbarry
86.05
-0.23
-
No. 6 Murtho
19.25
-0.01
+0.50
No. 15 Euston
47.60
-0.26
-
No. 5 Renmark
16.30
+0.04
+0.59
No. 11 Mildura
34.40
+0.01
+0.51
No. 4 Bookpurnong
13.20
+0.16
+1.31
No. 10 Wentworth
30.80
-0.02
+0.71
No. 3 Overland Corner
9.80
+0.05
+0.74
No. 9 Kulnine
27.40
+0.01
-0.02
No. 2 Waikerie
6.10
+0.11
+0.75
No. 8 Wangumma
24.60
-0.60
+0.62
No. 1 Blanchetown
3.20
+0.16
+0.31
Lower LakesFSL = 0.75 m AHD
Lake Alexandrina average level for the past 5 days (m AHD)
0.80
Barrages Fishways at Barrages
Openings
Level (m AHD)
No. Open
Rock Ramp
Vertical Slot 1
Vertical Slot 2
Dual Vertical Slots
Goolwa
128 openings
0.82
4
-
Open
Open
-
Mundoo
26 openings
0.80
2
-
-
-
Open
Hunters Creek
-
-
-
-
Open
-
-
Boundary Creek
6 openings
-
1
-
Open
-
-
Ewe Island
111 gates
-
All closed
-
-
-
Open
Tauwitchere
322 gates
0.84
12
Open
Open
Open
-
AHD = Level relative to Australian Height Datum, i.e. height above sea level
Week ending Wednesday 22 Jul 2020
State Allocations (as at 22 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 :
http://www.environment.sa.gov.au/managing-natural-resources/river-murray