Upload
others
View
1
Download
0
Embed Size (px)
Citation preview
23 July 2020
Namoi ROSCCo(River Operations Stakeholder Consultation Committee)
WaterNSW
Namoi Valley Map
2
WaterNSW
• Rainfall and climate
• Allocations and Usage
• Restrictions
• Supplementary access
• 14 media releases relating to restrictions and extraction in northern valleys alone
from 17 Jan to 25 Feb 2020
• https://www.waternsw.com.au/__data/assets/pdf_file/0009/145287/Operations-
Update-Namoi-1-July.pdf
• https://www.waternsw.com.au/__data/assets/pdf_file/0018/151641/191206-
Operations-Update-Upper-Namoi.pdf
• https://www.waternsw.com.au/about/newsroom/2020/324-temporary-pump-
restrictions-for-northern-valleys
3
Part 1 - Overview of 2019/2020
WaterNSW4
Rainfall – last 24 months
WaterNSW5
Rainfall – last 12 months
WaterNSW6
Temperature – last 12 months
WaterNSW7
Rainfall – last 3 months
WaterNSW
https://waterregister.waternsw.com.au/water-register-frame
8
2019/20 Water AvailabilityUpper Namoi
WaterNSW
2019/20 Water AvailabilityLower Namoi
9
WaterNSW
• The 2020 Northern Basin First Flush Event:
• Followed an extensive period of hot and dry conditions with record low rainfall and record low inflows
• Included significant inflows from across the Northern Basin including the Border, Moonie, Gwydir, Namoi, Culgoa, Bokhara, Macquarie, Bogan and Warrego systems.
• Involved a large number of Temporary Water Restrictions being placed on extractions in the Northern Basin.
• Raised issues regarding communication and decision making processes.
• Resulted in the appointment of an Independent Panel to assess the management of the event
– https://www.industry.nsw.gov.au/water/allocations-availability/northern-basin-first-flush-assessment
– Terms of Reference, consultation, Water User Reference Group
– Final report with recommendations – end of August 2020
• Resulted in around 585 GL of inflow arriving into the Menindee Lakes system.
WaterNSW published regular Operations Updates throughout the event at https://www.waternsw.com.au/supply/regional-nsw/operations-updates
A draft report is available at https://www.industry.nsw.gov.au/water/allocations-availability/northern-basin-first-flush-assessment
A webinar will also be held on Monday 27 July from 1:00 to 2:30pm. Registration for the Webinar is required.
10
Northern Basin First Flush Event
WaterNSW
• 17 Jan - https://www.waternsw.com.au/about/newsroom/2020/324-temporary-pump-restrictions-for-northern-valleys
• 26 Jan - https://www.waternsw.com.au/about/newsroom/2020/pump-restrictions-lifted-for-peel-high-security-and-unregulated-use-on-mooki-and-quirindi-systems
• 31 Jan - https://www.waternsw.com.au/about/newsroom/2020/324-pump-restrictions-extended-for-northern-valleys
• 7 Feb - https://www.waternsw.com.au/about/newsroom/2020/temporary-rule-change-to-allow-some-stock-water-trade
• 7 Feb - https://www.waternsw.com.au/about/newsroom/2020/temporary-pump-restriction-on-floodplain-harvesting
• 10 Feb - https://www.waternsw.com.au/about/newsroom/2020/approval-to-take-under-temporary-water-restrictions-information
• 11 Feb - https://www.waternsw.com.au/about/newsroom/2020/approval-to-take-under-temporary-water-restrictions-11-february
• 11 Feb - https://www.waternsw.com.au/about/newsroom/2020/324-orders-on-floodplain-harvesting-in-the-northern-basin
11
Media releases
WaterNSW
• 12 Feb - https://www.waternsw.com.au/about/newsroom/2020/amendment-to-
temporary-pump-restriction-on-floodplain-harvesting
• 12 Feb - https://www.waternsw.com.au/about/newsroom/2020/temporary-
water-restriction-northern-nsw-murray-darling-basin-yarraman-creek-12-
february-2020
• 13 Feb - https://www.waternsw.com.au/about/newsroom/2020/temporary-
water-restrictions-on-river-and-overland-flows-in-the-northern-basin
• 14 Feb - https://www.waternsw.com.au/about/newsroom/2020/324-pump-
restrictions-extended-for-northern-valleys2
• 21 Feb - https://www.waternsw.com.au/about/newsroom/2020/barwon-darling-
flows-a-blessing-for-towns,-farmers
• 25 Feb - https://www.waternsw.com.au/about/newsroom/2020/324-pump-
restrictions-lifted-in-namoi,-border-rivers
12
Media releases
WaterNSW13
Supplementary Access 19/20
Event Volume calculations MLNarrabri Creek @ Narrabri 9/02/2020 to 7/03/2020 117422
Brigalow Creek inflow 9/02/2020 to 7/03/2020 2653
Total Flow 120075
Total Available Share 120075
less volume proir to trigger 94
less volume to fill weirs 0
less volume to meet Pian Creek repenishment 4700
D/S orders/requirements (riparian flows) 1783
less volume after cease 164
Available flow to be shared 113334
50% Consumptive share 56667
Volume Announced A 2452
Volume Announced B 0
Total Volume Announced 2452
Total Supplementary extracted 2452
Over Pumping debited to other accounts 0
Total Supplementary Pumping 2452
Percentage announced 2.2%
Percentage extracted 2.2%
Notes:
10 hours access for A Class Narrabri to Weeta.
48 hours access for A class Weeta to Walgett.
No B class access.
Up to 50% supplementary volume able to be extracted 1 November to 30 June
Restrictions applied to event.
Lower Namoi Supplementary Event 1 2019/2020
WaterNSW
Supplementary Access 19/20
Event Volume calculations MLBugilbone gauged inflow 12 March to 14 March 3016
Total Flow 3016
Total Available Share 3016
less volume proir to trigger 0
less volume to fill weirs 0
less volume to meet Pian Creek repenishment 0
D/S orders/requirements (riparian flows) 362
less volume after cease 0
Available flow to be shared 2654
50% Consumptive share 1327
Volume Announced A 1388
Volume Announced B 0
Total Volume Announced 1388
Total Supplementary extracted 1388
Over Pumping debited to other accounts 0
Total Supplementary Pumping 1388
Percentage announced 52.3%
Percentage extracted 52.3%
Notes:
8 hours access for A Class - Weeta to Walgett.
No B class access.
Up to 50% supplementary volume able to be extracted 1 November to 30 June
Lower Namoi Supplementary Event 2 2019/2020
14
WaterNSW15
Supplementary Access 19/20
Event Volume calculations MLNarrabri Creek @ Narrabri 8 April to 17 April 7382
Ungauged inflow (positive AUD Weeta to Bullawa 12 to 16 April) 1437
Brigalow Creek inflow - gauged flow 11 April to 13 April 399
Total Flow 9218
Total Available Share 9218
less volume prior to trigger 121
less volume to fill weirs 0
less volume to meet Pian Creek repenishment 0
D/S orders/requirements (incl riparian flows) 0
less volume after cease 286
Available flow to be shared 8811
50% Consumptive share 4406
Volume Announced A 4074
Volume Announced B 0
Total Volume Announced 4074
Total Supplementary extracted 4074
Over Pumping debited to other accounts 0
Total Supplementary Pumping 4074
Percentage announced 46.2%
Percentage extracted 46.2%
Notes:
Total 45 hours access for all A Class
No B class access.
Up to 50% supplementary volume able to be extracted 1 November to 30 June
Lower Namoi Supplementary Event 3 2019/2020
WaterNSW16
Supplementary Access 19/20
Event Volume calculations MLBugilbone gauged inflow 17 to 18 April 371
Total Flow 371
Total Available Share 371
less volume proir to trigger 0
less volume to fill weirs 0
less volume to meet Pian Creek repenishment 0
D/S orders/requirements (riparian flows) 0
less volume after cease 0
Available flow to be shared 371
50% Consumptive share 186
Volume Announced A 195
Volume Announced B 0
Total Volume Announced 195
Total Supplementary extracted 195
Over Pumping debited to other accounts 0
Total Supplementary Pumping 195
Percentage announced 52.6%
Percentage extracted 52.6%
Notes:
20 hours access for A Class - Bugilbone to Walgett.
No B class access.
Up to 50% supplementary volume able to be extracted 1 November to 30 June
Lower Namoi Supplementary Event 4 2019/2020
WaterNSW
• Drought Update
• Drought Map
• Inflows
• WNSW Water Insights Portal
17
Part 2 - Current Situation
WaterNSW
WaterNSW
Regional drought map
WaterNSW
• Split Rock Dam inflows since Jan 2020
to end June 2020 have been 16GL
• Just above 50th%ile of 12.7GL
• Split Rock Dam inflows since July 2018
to end June 2020 have been 20GL
just above minimum of 11GL (95th%ile
is 24GL)
20
Namoi Valley Inflows
WaterNSW
• Keepit Dam inflows since Jan 2020 to end June 2020 have been 61GL
• In line with 50th%ile inflows of 61.5GL
• Downstream tributary flow has been approximately 105GL.
• Keepit Dam inflows since July 2018 to end June 2020 have been 66.5GL(excluding BWT) just above minimum of 53GL
• Downstream tributary flow for the 24 month period has been approximately 116GL.
21
Namoi Valley Inflows
Water Insights
• Storage levels
• Inflows
• Releases
• Compare multiple years
• Allocations
• Outlook
• more
22
WaterNSW23
https://waterinsights.waternsw.com.au/11986-lower-namoi-regulated-river/updates
Keepit & Split Rock Dam
WaterNSW24
Allocations (screen shots from WaterInsights)
WaterNSW
• Storage Forecasts
• Climate outlook
• Allocations
• Operations
• Projects
25
Part 3 – Outlook for 2020/2021
WaterNSW26
Storage Forecast
WaterNSW27
Storage Forecast
WaterNSW28
Rainfall outlook August to October
WaterNSW29
Rainfall outlook September to
November
WaterNSW30
Operations 2020/2021
River section Licence category Type of restriction Period of
applicability
Method of placing water order
Upper Namoi
(Split Rock Dam to upstream of Keepit)
High Security
General Security
Stock & Domestic
Local Water Utility
Tributary inflows will continue to be utilised where possible. Minimal dam releases will be made to provide access to account water.
A water order is still required to be placed and needs to be approved by WaterNSW.
Until further notice Via iWAS or the customer help desk
Confirmation of water order from WaterNSW is required.
Lower Namoi
(downstream of Keepit Dam to Walgett)
High Security
General Security
Stock & Domestic
Local Water Utility
Tributary inflows will continue to be utilised where possible. No Dam releases will be made to supply orders or the Pian Ck replenishment flow however in order to provide for some deliveries, a block release strategy may be considered with favourable downstream conditions
Access will be made available from tributary inflows where possible.
A water order is still required to be placed and needs to be approved by WaterNSW.
Until further notice Via iWAS or the customer help desk
Confirmation of water order from WaterNSW is required.
WaterNSW
▪ Potential Block release: S&D/riparian/replenishment/general security for Lower
Namoi
▪ Namoi @ U/S Walgett gauge – impacted by back water
31
Discussion Points
WaterNSW
• $2000 Water Carting rebate
available through Service NSW
• https://www.service.nsw.gov.au
/transaction/apply-water-
carting-rebate
• helps with the cost of carting
water or installing water tanks
and pipes
• to help secure domestic water
needs
• available in the Upper Namoi
downstream of Manilla and in
the Lower Namoi downstream
of Keepit
32
Water Carting Rebate
WaterNSW
33
GROUNDWATER RESOURCE STATUS INFORMATION
• Upper and Lower
Namoi Alluvium
Groundwater
Sources
• This presentation is an initiative by WaterNSW to gather groundwater resource status information for various groundwater sources in NSW
Part 4 – Groundwater (a snapshot)
WaterNSW
• The surface geology of the Namoi Catchment comprises five main units namely:
➢ Palaeozoic New England Fold Belt
➢ Palaeozoic to Mesozoic Gunnedah Basin
➢ Mesozoic Great Artesian Basin (GAB)
➢ Cenozoic unconsolidated sediments
➢ Cenozoic extrusive volcanics
➢
34
Geology
WaterNSW35
Cross Section
Upper Namoi Alluvium
Gunnedah-Oxley Basin MDB, GAB and New England Fold Belt
WaterNSW
• Upper Namoi Alluvium
➢ Groundwater salinity across the Upper Namoi Alluvium is generally less than 1,500 μS/cm
➢ Some areas of higher salinity up to 20,000 μS/cm
➢ Upper Namoi Zone identified increasing depth salinity
➢ The shallow alluvium salinity ranges between approximately 6,000-18,000 μS/cm
➢ The deeper aquifer ranged between 600 and 14,000 μS/cm
36
Groundwater Quality
Lower Namoi Alluvium
➢ Groundwater salinity in the main body of the Lower Namoi Alluvium is generally less than 1,500 μS/cm
➢ Salinity increases with distance from the recharge areas to more than 20,000 μS/cm in the southern and western margins
➢ At the western margin of the Lower Namoi Alluvium, deeper low salinity groundwater is overlain by a highly saline water table aquifer
➢ Lack of river recharge in this area has the potential for deep aquifer salinization due to vertical leakage
WaterNSW
• correlation between water level response and extraction pattern
37
Groundwater Extraction and
Winter Recovery Level
0
5
10
15
20
25
30
350
20
40
60
80
100
120
140
2006-2007 2007-2008 2008-2009 2009-2010 2010-2011 2011-2012 2012-2013 2013-2014 2014-2015 2015-2016 2016-2017 2017-2018 2018-2019 2019-2020
Win
ter
Re
co
ve
ry L
eve
l (
m)
An
nu
al G
rou
nd
wa
ter
Extr
ac
tio
n (
GL)
Water Year
LOWER NAMOI ALLUVIUM GROUNDWATER SOURCE
Groundwater Extractions and Recovered Water Level 2006-2020
GW Extraction
Winter Recovery Level 2006-2020 GW021266 Screen Depth 107.3-113.4 mbgl
No data
WaterNSW
Visit the website at:
waternsw.com.au/drought
For information including water availability reports and
drought reports go to:
https://www.waternsw.com.au/supply/drought-
information/regional-nsw
Call us on:
1300 662 077
Subscribe at:
waternsw.com.au/subscribe
For weekly customer drought updates and more
information
38
To keep updated
WaterNSW
End of Presentation