Water Availability Report

Transcription

1 Water Availability Report 8 October 218 Table of Contents Overview... 2 System Risks... 2 Climatic Conditions Month Forecast Climatic Conditions... 4 Valley Based Operational Activities... 5 Murray Valley... 5 Lower Darling Valley... 7 Murrumbidgee Valley... 8 Lachlan Valley Macquarie Valley Namoi Valley Gwydir Valley Border Rivers... 2 Barwon Darling River System Bega River Hunter Valley Toonumbar Dam WaterNSW (Rural) Dam Levels Subscribe here for updates to the Water Availability Report. For Greater Sydney Water Availability, please follow the below link: Page 1 of 28

2 Overview WaterNSW manages and operates 42 dams and storages to deliver water for environmental, domestic, town water, stock, industrial and irrigation purposes across the state. WaterNSW storages provide supplies to all the major river systems in Western NSW, Greater Sydney, the Southern Highlands, Shoalhaven Bay as well as the Hunter, Bega, and Iron Pot valleys in coastal NSW. The total active storage percentage of rural water supplies on 8 October 218 was 49.1% of the total active storage capacity. This was a decrease of.9% from last week. The total storage level of urban water supplies on 8 October 218 was 62.9% of the total storage capacity. This was a decrease of.1% from last week. System Risks Low inflows are being experienced across the state with the ongoing drought conditions. The actual inflows to Burrendong Dam since the last AWD in August 217 total about 35 GL. This is only 26% of the previous record low inflow of about 133GL for the 14 months ending in September. Only 7% of remaining carryover can be delivered with the current stored volumes and these new, lower inflows. Environmental water delivered from the environmental licences in the regulated Macquarie River being extracted by the irrigation licences in the unregulated lower Macquarie and Gum Cowal systems. The Barwon-Darling system has ceased to flow for the full length from Mungindi to Menindee as conditions remain dry. The continuing dry conditions in the Namoi Valley, mean that remaining water will be delivered via a single block release strategy from October through to December 218. Planning in relation to timing and duration of releases is being finalised. Cease to flow conditions have been present since late March below Goangra in the Lower Namoi Valley. Drought contingency measures (block releases) are scheduled in the Gwydir valley to deliver the small volumes remaining in customer accounts as conditions remain dry in 218/19. Grouping of water orders and an early cessation to deliveries in the western section of the Border rivers will be required if conditions remain dry in 218/19. Menindee Lakes continues to be below the 48/64GL trigger for NSW control, and reduced releases have been implemented to extend drought security. These lower releases increase the possibility of; access problems with very low flows and decreasing water quality. Temporary block banks are being constructed in the Lower Darling to extend stock and domestic supplies beyond December 218. Page 2 of 28

3 Climatic Conditions Figure 1 - Weekly rainfall totals for New South Wales A trough in the far west of the state is forecast to move through western and southern districts on Monday and north-easterly districts on Tuesday. During Thursday and Friday, the trough is expected linger over parts of the northern inland while a strong high-pressure system moves from the Bight across to the Tasman Sea, extending a ridge along the New South Wales coast as it does so. Figure 2a First 4-day Forecast (9 12 Oct 18) Figure 2b Following 4-day forecast (13 16 Oct 18) Page 3 of 28

4 3 Month Forecast Climatic Conditions A drier end to the year likely for parts of eastern and southern Australia October to December is likely to be drier than average for parts of eastern and southern Australia. Specifically, scattered parts of southern and western NSW are likely to have a drier than average October to December. October is likely to be drier than average for most of NSW, but there are roughly equal chances of a wetter or drier three months over the east of the Great Dividing Range. Much of eastern and southern mainland Australia have been very dry and warm since the start of the year. The October to December outlook indicates current drought areas are unlikely to see significant respite in the coming three months. Figure 3 - Three-month rainfall outlook Page 4 of 28

5 Valley Based Operational Activities Murray Valley Storage Status Hume Dam is currently at 51% of active capacity, releasing about 15,5 ML/d. Predicted Release Patterns Releases from Hume Dam have now increased in response to the low downstream tributary inflows, increased early season demands and higher river losses. As Menindee lakes are not available releases are expected to continue at the current rate to meet irrigation / environmental demands and to transfer water to Lake Victoria. Release downstream of Yarrawonga Weir is about 15,ML/day. This higher flow will be passed through specific forest regulators to take advantage of pre-wetted anabranch channels that can transfer water efficiently around the Barmah Choke. The higher flows are required to ensure sufficient water is transferred to Lake Victoria in advance of expected system demands over summer and into autumn. Forest regulators would be actively used to maintain the Picnic Point below 2.6m. Currently the level at Picnic Point is about 2.48m. The Edward River Offtake is currently about 1,565ML/d and is likely to remain relatively steady below the channel capacity of 1,6ML/day. The Gulpa Creek Offtake is currently about 336ML/d and is likely to remain relatively steady below the channel capacity of 35ML/day. Stevens Weir level is currently about 4.47m and is likely to remain relatively steady to manage the level upstream of Wakool Canal offtake, which is about 1.77m. Flow downstream of Stevens Weir is currently about 3,ML/day and is likely to remain relatively steady. Flows in the Colligen Creek (4ML/day), Yallakool Creek (425ML/day) and Wakool River (6ML/day) are likely to remain steady. The combined Wakool Yallakool flows are augmented with supply from Mulwala Escape at Wakool so that the flows are maintained at about 6ML/day in the Wakool system. Operating Conditions The latest Water Allocation Statement by DOI-Water confirmed that the general security allocation of zero, while Available Water Determinations (AWD) are 1% for towns and 97% for high security. Average carryover into is estimated to be about 31% of general security share components. Returns to Edward River upstream of Toonalook from the environmental water delivered into the Barmah Millewa forest is currently averaging about 1,25ML/d. Environmental water delivery to Wakool-Yallakool and Colligen-Neimur Creek systems as per the hydrograph provided by Fisheries have been suspended. The flows are now managed to maximise the delivery to Murray using the Edward Wakool system subject to channel capacity in the Wakool system. Supply through Perricoota Escape (9ML/day) and Wakool Escape (13ML/day) are expected to continue for next few weeks. Supply to Edward River is also augmented though the use of Billabong Escapes at Finley, (25ML/day). The escape delivery is expected to increase to the capacity of about 3ML/d later this week. Page 5 of 28

6 Flow at Moulamein, which is currently at about 2,4ML/day is likely to increase steadily to about 2,8ML/day by next week. Flow in Niemur River at Mallan School is currently about 5ML/d and is likely to increase gradually to 7ML/day over the next two weeks. Meeran Creek flows are about 163ML/day and is likely to gradually increase to about 2ML/day in the next wo weeks Flow in Wakool River at Stoney Crossing is currently at about 1,ML/day and is expected to gradually increase to about 1,2ML/day in the next two weeks. Flows at Balranald are currently about 1,327 ML/d and likely to increase in the short term due to operational surplus before reducing to target about 1,1ML/day for the rest of October 218. Lake Victoria is currently holding about 373 GL or 47% of active capacity. The flow to South Australia is about 5,98ML/d. Potential Blue Green Algae issues. o Hume Dam: Results for September show a minor detection of benign cyanobacteria (Aphanocapsa sp.) across the storage. The assemblage at all sites was dominated by diatoms. No potentially toxic species were detected. Storage remains at green alert. o For more information visit: Water Quality Algae Planned Supply Interruptions: None. Page 6 of 28

7 Lower Darling Valley Storage Status The lakes currently hold an active volume of about 13 GL or about 6% of active capacity. The total storage is about 15 GL. Lake Menindee has been dry since 6 Feb 218. Predicted Release Patterns Release from Lake Pamamaroo is about 26ML/d, primarily to meet the flow targets of about 22ML/d at Weir 32 to fill the Lower Darling block banks. The following is the tentative plan for releases from upper storages to fill the banks: o Weir 32 target will remain at 22ML/d. The release will be regularly reviewed as the Lake Pamamaroo outlet capacity will reduce as the lake level falls. o The supply to Lower Darling River from Pamamaroo is expected to be maintained at about 26ML/d until mid-november and is subject to Pamamaroo outlet release capacity. o Current level at the block bank near Jamesville is about 2.94, and one pipe has been closed to increase the level at about 2 mm/day. o Current level at the block bank near Ashvale is about 1.94m. The pipes at the bank are closed. The filling rates of both banks are regularly reviewed. Operating Conditions The latest Water Allocation Statement by DOI-Water confirmed the Available Water Determinations (AWD) are 1% for towns for high security, while general security is zero. Average carryover into is about 15% of general security share components. The average pan evaporation rate at Menindee over the last week was about 6.9mm/d equivalent to about 4,6ML from the lakes over the week. The total storage of Menindee Lakes reached the 48GL trigger for NSW control of the lakes on 16 December 217. The releases from the storages will be managed as per the Lower Darling Annual Operations Plan until the storage volume next exceeds 64GL. For more information visit: Lower-Darling Operational Plan. The pumping across the temporary bank between Lake Wetherell and Lake Tandure ceased on 18 May 218 as it reached the targeted water level in Lake Wetherell. Pumping will recommence when required to maintain this target level. Two temporary block banks viz. near Jamesville and Ashvale have been constructed to ensure supply to domestic, stock and permanent plantings. Additional releases from Lake Pamamaroo outlet have commenced to fill these banks. Construction of the temporary bank to separate Lake Pamamaroo and Copi Hollow has been completed and pumping is commenced on Saturday 22/9/18 at the rate of about 3ML/day. About 3,8ML has been transferred into Copi Hollow todate. Potential Blue Green Algae issues. The following warnings are current for the various sampling locations within the Menindee Lake System and Lower Darling River immediately downstream of the storages. o Darling River at Wilcannia, Darling River u/s in Weir 32, Darling River at Weir 32, Lake Wetherell - Site 1,2,3,4, Lake Tandure- Site 8, Lake Pamamaroo Site 9,1,13, Copi Hollow, Darling River Pumping Station at Menindee, Lake Cawndilla Outlet are on green alert. o There is no current alert for Lake Menindee - Site 19. For more information visit: waterquality-algae Planned Supply Interruptions None Page 7 of 28

8 Murrumbidgee Valley Storage Status Burrinjuck Dam is currently at about 42% releasing about 45 ML/d. Blowering Dam is about 64% releasing about 8,8 ML/d. Predicted Release Patterns Releases from Burrinjuck Dam are being maintained as per planned environmental water rules Release from Blowering Dam would be reduced to about 6,5ML/day to meet irrigation and environmental demands in the system The current diversion into Yanco Creek is about 5 ML/d and is likely to remain relatively steady. Delivery to Yanco Creek via CCD escape is about 5ML/day and DC8 about 3ML/day. Delivery to Billabong system via Finley Escapes is about 22ML/day and is likely to increase to about 3ML/day later in the week. The Beavers Creek Offtake is controlled to achieve a target of around 4ML/day as an average flow in October at Kywong. Operating Conditions The latest Water Allocation Statement by DOI-Water confirmed the Available Water Determinations (AWD) are 1% for towns and 95% for high security, while general security is now 7%. Carryover into is 22% of general security share components. Berembed Weir is currently at about 4.27m and the storage would gradually be lowered to meet downstream demands. The weir would be targeted to maintain a level of about 4.m to be filled to full supply level with future rainfall event or with any system surplus. Bundidgerry storage has been drawn down to 2.4m to meet unplanned increase in irrigation demand. The storage is expected to be increased to about 3.6m in the next few days to provide necessary buffer for meeting short term demands. From then on Bundidgerry would be maintained at about the same level to provide sufficient airspace to capture any system surplus. Gogeldrie Weir is currently at about 5.2m. The Weir would be actively used for re-regulation capture any system surplus and then to meet downstream system demands while maintaining sufficient head (about 5.6m) to supply water to meet the pre-watering irrigation demand to Sturt Canal and Coleambally Main Canal. Tombullen storage is about 1.3m and is being used to meet downstream demands. Hay Weir is currently at 8.56m and is likely to be gradually drawn down to 6.5m over the next two weeks to meet downstream demands. Maude Weir will be maintained at operational full supply level of about 5.9m to enable diversion into South Caira channel and Nimmie Creek for environmental water orders for the next six weeks. Redbank Weir is at operational full supply level of about 5.6m to supply environmental water to Yanga wetlands. The supply of ewater commenced on 2 August and is likely to continue into summer. Environmental water delivery to Lowbidgee area via North Redbank channel is likely to continue at about 3ML/day for the next three to four weeks. Flows at Balranald are currently about 1,327 ML/d and likely to increase in the short term due to operational surplus before reducing to target about 1,1ML/day for the rest of October 218. Page 8 of 28

9 For Inter Valley Transfer (IVT) account from Murray to Murrumbidgee refer to WaterNSW website IVT Ordering Potential Blue Green Algae issues: o Green alerts are current for the following sites: Murrumbidgee River at Hay Weir Buoy, Murrumbidgee River at Maude Weir Buoy and Murrumbidgee River at Balranald. o Other sites have no alerts. o For more information visit: water-quality-algae Planned Supply Interruptions The four low level valves at Burrinjuck Dam are currently under maintenance and are expected to return to service in two weeks time. However, during this period the required storage releases would be met from the Hydro Electric Power Station outlet. Planning is underway for the maintenance of Tarabah Weir as the maintenance is team is awaiting a suitable window of low flows. At Spillers Regulator the new gate is to be installed and a suitable window of low flows needs to be provided for the purpose. Meanwhile, a temporary board has been placed to maintain minimal flows in the Washpan Creek. Page 9 of 28

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11 Lachlan Valley Storage Status Carcoar Dam is at 53% and releases have averaged about 45 ML/d during the last week. Wyangala Dam is at 52% and releases have averaged about 2,3ML/d during the last week. Predicted Release Patterns The releases from Carcoar Dam will be around 4 ML/d subject to orders and rainfall. The releases from Wyangala Dam are likely to be around 15 ML/d for the upcoming week. In the Lower Lachlan, the releases at Brewster Weir have been averaging around 45 ML/d. Of this an average of around 14 ML/d was released for Stock & Domestic replenishment flows to Willandra Creek. Operating Conditions There is currently an environmental fish pulse travelling through the system that was released from Wyangala Dam, and this order was released on top of operational demand. The pulse targeted a peak of 2,6ML/d at Forbes between the 3 th August and the 12 th September. This environmental water will then travel through the system to the Cumbung swamp. Environmental flows in Booberoi Creek ended on 18 th Sept and the current flows are just under 3ML/d. The 14 th September Water Allocation Statement confirmed zero for general security and the initial Available Water Determinations (AWD) of 1% for towns, S&D and high security. Carryover into in Lachlan River is about 369GL, equivalent to about 62% of general security share components. It was estimated that a combined dam and tributary inflow volume more than 168, ML were required in September before a further allocation can be made in the Lachlan River. Inflows received in September were around 7,ML. Lake Cargelligo storage is currently at 65% and the level is likely to remain between 4% and 8% during the irrigation season. As of 25 July 218, Lake Brewster main storage is effectively empty. Starting on the 27 September there has been environmental water being delivered into the outflow wetlands, with the goal of building the seedbank through a full growth cycle. Latest BGA samples show that Willandra Weir, Lake Brewster outlet channel, Lake Brewster Regulator C, Lake Cargelligo Outlet and Boatshed are all on green alert. Delivery of annual stock and domestic replenishment flows to effluent creeks in the lower Lachlan have been staggered. Merrimajeel/ Muggabah commenced on 12th June 218 and finished on the 7 th August 218. Stock and domestic replenishment flows into Merrowie Creek started on 11 May 218 and finished on the 2 July 218. Willandra Creek commenced on the 27 July 218 and currently nearing completion. Page 11 of 28

12 Planned Supply Interruptions Nil. Account spill and reset of general security allocations If WaterNSW were to commence dam releases to maintain airspace in Wyangala Dam, it will trigger an account spill and reset of general security allocation accounts, high security spillable sub-accounts and the conveyance licence account as per section 56 of the Lachlan WSP. The Department of Industry - Water has announced that if there is an account spill and reset there will be no further reset in the following 6 months. Page 12 of 28

13 Macquarie Valley Storage Status Burrendong Dam is currently at 24.6% and Windamere Dam is at 4% of capacity. Predicted Release Patterns Currently releases from Burrendong are around 2,1 ML/d and are planned to remain in between18-21ml/d during the week. Releases from Windamere are currently around 5ML/d and are planned to remain steady depending on irrigation demand. Operating Conditions Delivery of environmental flows commenced at Burrendong Dam on 12 July 218. Currently releases for the spring event are being made from the dam with a hydrograph designed to provide a peak flow rate of 2,4 ML/d at Marebone Weir. The current releases from Burrendong Dam are for environmental orders, and for irrigation, town water demand and minimum flow targets. The S&D flow requirements in the lower Macquarie River are likely to be met by the current delivery of environmental flows to the Macquarie Marshes. The flows draining through the Marshes are at Bells Bridge at Carrinda, with a current flow rate of around 8Ml/d and increasing. The timing of all S&D deliveries thereafter in 219 will depend on rainfall events, dam inflows, and contributions from downstream tributaries. The initial Available Water Determinations (AWD) for are 1% for towns, S&D and high security, while general security is zero. Carryover into in the Macquarie River was about 316GL or 52% of general security share component. Carryover into in Cudgegong River was about 12% of share component. However, as per the Temporary Water Restriction Order by DoI Water, the resources in Burrendong Dam, minimum expected inflows, plus planned bulk water transfer of 54, ML from Windamere Dam, will only provide 7 per cent of the 1 July 218 balance of general security and environmental accounts (including EWA). The Order states that, Macquarie regulated river (general security) access licences will be restricted to 7 per cent of the volume of water in the carryover sub-account account as at 1 July 218. Cudgegong regulated river access licences, including general security, are not restricted. As inflows are received during the year the amount of water in the drought reserve will be reduced and be made available to customers. It was estimated that inflows of more than 3 GL are required in September before an increment in Available Water Determination could be made. Inflows received in September are approximately 5GL. The actual inflows to Burrendong Dam since the last AWD in August 217 total about 35 GL. This is only 26% of the previous record low inflow of about 133GL for the 14 months ending in September. This drier than historical minimum inflow confirms that the system has entered into a new drought of record for Burrendong Dam, and the next few months inflows will be important for planning this season s operations. Page 13 of 28

14 Jul-15 Aug-15 Oct-15 Dec-15 Feb-16 Apr-16 Jun-16 Aug-16 Oct-16 Dec-16 Feb-17 Apr-17 Jun-17 Aug-17 Oct-17 Dec-17 Feb-18 Apr-18 Jun-18 Aug-18 Oct-18 Dec-18 Feb-19 Apr-19 Jun-19 End of Month Storage Level in % Under very dry conditions, deliveries in will require water conservation initiatives to reduce losses. This may involve implementation of water order debiting and, where feasible, block releases of irrigation orders in lower parts of the Macquarie River. Burrendong algal results for the 18 th Sept show a minor presence of toxic species at the Dam Wall. Storage is now on Green alert however weekly sampling will continue as part of the curtain reinstatement. Windamere algal results for the 5 th Sept shows a minor presence of toxic species at Dam Wall and mid lake, however storage remains on green alert. The position of the trash rack at Windamere Dam is currently m below the surface. Works to reinstate the temperature curtain at Burrendong Dam have been completed and the commissioning phase has commenced. It is expected that the commissioning of the curtain operation will be completed by the time the water near the surface of the lake begins to warm. This will allow continuation of this trial technology with the release of the lake s warmer surface waters. Customers are reminded that those who repeatedly extract less water than indicated in their approved water order will have their account debited for the full amount ordered, rather than the amount extracted. Please view the approved water order debiting rules as below: data/assets/pdf_file/6/122685/water-order-debiting_rev3.pdf Carryover evaporation reduction was applied on unsuspended (7%) carryover balances in HS and GS sub accounts in Macquarie and on carryover balances in Cudgegong Rivers for first quarter of A 1.3% reduction applied on Macquarie River and a.6% reduction was applied on Cudgegong River. Carryover balances in EWA account will also incur a 1.3% reduction. Planned Supply Interruptions Nil. 14% Burrendong Dam forecast storage levels (assessment done end of August 218) 12% 1% 8% 6% Actual Dry 8% COE Median 5% COE Wet 2% COE Minimum 99% COE 4% 2% % Page 14 of 28

15 Namoi Valley Storage Status Keepit Dam is at 11%, Split Rock Dam is at 13% and Chaffey Dam is at 49% of active capacity. Predicted Release Patterns Releases from Keepit Dam will begin from mid-october. Split Rock Dam is releasing around 5 ML/d to deliver small volumes to upper Namoi users. Chaffey Dam releases are on average 9 ML/day to supply Tamworth and small irrigation demand. Flows are expected to remain relatively stable, until warmer conditions occur. Operating Conditions The initial Available Water Determinations (AWD) for the Lower Namoi are 1% for towns and high security, while general security is zero. Carryover into is estimated to be up to 19% of general security share components. The initial Available Water Determinations (AWD) for the Upper Namoi are 1% for towns, high security, and general security. The initial Available Water Determinations (AWD) for the Peel are 1% for towns and high security, while general security initially was 29%, with an increase in October to a total of 38%. Some rainfall was recorded last week upstream of Chaffey Dam (between 5 and 2 mm); Some rainfall was recorded downstream of Dams (between 5 and 15 mm); no significant rainfall was recorded in other parts of the catchment. Some rainfall (between 5 to 15 mm on Wednesday through to Monday) is expected this week according to rainfall forecast. Temperatures are forecast to remain stable throughout the next week with maximums around 25 degrees and with minimums at 7 degrees. No flow has been present in the Namoi River at Walgett (Station No 41991) since March 218. The continuing dry conditions in the Namoi Valley, mean that remaining water will be delivered via a single block release strategy commencing in October. Planning in relation to timing and duration of releases is being finalised. Supply on demand will continue for the Upper Namoi and the Peel Valley. Recent sampling for BGA indicates that Split Rock Dam, Keepit Dam and Chaffey Dam are on a green alert. Planned Supply Interruptions Mollee fish way is currently unavailable due to infrastructure failure. Mollee and Gunidgera Weirs were both emptied to allow winter maintenance works and will only be replenished in October/November if they are not filled by additional tributary flows. Page 15 of 28

16 Sep-17 Oct-17 Nov-17 Dec-17 Jan-18 Feb-18 Mar-18 Apr-18 May-18 Jun-18 Jul-18 Aug-18 Sep-18 Oct-18 Nov-18 Dec-18 Jan-19 Mar-19 Apr-19 May-19 Jun-19 Jul-19 Aug-19 Sep-19 Oct-19 Nov-19 Dec-19 Jan-2 Feb-2 Mar-2 Apr-2 May-2 Jun-2 Jul-2 Aug-2 Gigalitres (GL) Sep-17 Oct-17 Nov-17 Dec-17 Jan-18 Feb-18 Mar-18 Apr-18 May-18 Jun-18 Jul-18 Aug-18 Sep-18 Oct-18 Nov-18 Dec-18 Jan-19 Mar-19 Apr-19 May-19 Jun-19 Jul-19 Aug-19 Sep-19 Oct-19 Nov-19 Dec-19 Jan-2 Feb-2 Mar-2 Apr-2 May-2 Jun-2 Jul-2 Aug-2 Gigalitres (GL) Keepit forecast storage volume - Chance of Exceedance (COE) Actual Minimum 99% COE DRY 8% COE Median 5% COE WET 2% COE Split Rock - forecast storage volume - Chance of Exceedance (COE) Actual Minimum 99% COE DRY 8% COE Median 5% COE WET 2% COE 1 5 Page 16 of 28

17 Aug-17 Oct-17 Nov-17 Dec-17 Jan-18 Feb-18 Mar-18 Apr-18 May-18 Jun-18 Jul-18 Aug-18 Sep-18 Oct-18 Nov-18 Dec-18 Jan-19 Feb-19 Mar-19 Apr-19 May-19 Jun-19 Jul-19 Aug-19 Sep-19 Oct-19 Nov-19 Dec-19 Jan-2 Feb-2 Mar-2 Apr-2 May-2 Jun-2 Jul-2 Gigalitres (GL) Chaffey Dam - forecast storage volume - Chance of Exceedance (CoE) actual Minimum 99% COE DRY 8% COE Median 5% COE WET 2% COE Page 17 of 28

18 Gwydir Valley Storage Status Copeton Dam is at 21% of active capacity. Predicted Release Patterns Planned releases from Copeton continue at around 15 ML/d. Operating Conditions The initial Available Water Determinations (AWD) are 1% for towns and high security, while general security is zero. Total carryover into is estimated to be up to 22% of general security share components. Some rainfall was recorded early last week upstream of Copeton Dam (from 2 to 7 mm at several locations); some rainfall was recorded downstream of Copeton Dam and upstream of Moree (from 5 to 2mm at several location), and no significant rainfall in other parts of the catchment. Some rainfall (from 5 up to 25 mm on Wednesday through to Friday) is expected this week according to Rainfall forecast. Temperatures are forecast to remain stable throughout the next week with maximums around 25 degrees and with minimums below 1 degrees. Consultation with customers in relation to limited water deliveries this season has begun. Carryover of general security for industry production was limited to roughly 4 GL (about 8% of general security share components). Carryover of general security for environmental use is roughly 71 GL (about 14 % of general security share components), in addition roughly 75 GL is available for the Environmental Contingency Allowance (ECA). The first of two planned 3GL ECA deliveries is underway and flows have already reached the target sites; Millewa and Gingham. The first of two planned 1GL CEWO (Commonwealth Environmental Water Office) Mallowa Creek deliveries is underway, flow has reached Mallowa Creek off-take. The first delivery (1GL) is planned from September to early December. The second (1GL) is planned from end of January to early April. If conditions remain dry the delivery of remaining volumes will need to be managed so that essential supplies can be met going forward. Block releases will be required on western effluent streams. No further winter deliveries to effluent streams will occur. Customer Notice Recent Blue Green Algae (BGA) sampling at Copeton shows Copeton at amber alert level. Planned Supply Interruptions No supply interruptions are expected. Page 18 of 28

19 Sep-17 Oct-17 Nov-17 Dec-17 Jan-18 Feb-18 Mar-18 Apr-18 May-18 Jun-18 Jul-18 Aug-18 Sep-18 Oct-18 Nov-18 Dec-18 Jan-19 Mar-19 Apr-19 May-19 Jun-19 Jul-19 Aug-19 Sep-19 Oct-19 Nov-19 Dec-19 Jan-2 Feb-2 Mar-2 Apr-2 May-2 Jun-2 Jul-2 Aug-2 Gigalitres (GL) Copeton - forecast storage volume - Chance of Exceedance Actual Minimum 99% COE DRY 8% COE Median 5% COE WET 2% COE Page 19 of 28

20 Border Rivers Storage Status Pindari Dam is at 49%. Glenlyon is at 44%. Predicted Release Patterns Pindari Dam is currently releasing around 57 ML/day and are likely to change later this week depending on orders. Glenlyon Dam is currently releasing around 5 ML/day. Operating Conditions The initial Available Water Determinations (AWD) are 1% for towns and high security, while general security A is 23% and general security B is zero. Total carryover into is around 53% of general security share components. Some rainfall was recorded throughout the last week. But that was not enough to generate any significant inflow to the dams. Some rainfall is forecast by BoM for this week. Temperatures are forecast to remain stable throughout the week with maximums around high 2 degrees and with minimums between 5 to 15 degrees. Releases from Boggabilla Weir are currently around 84 ML/day and will charge frequently depending on downstream orders. Boomi replenishment flow is now finished - approximately 2,9 ML was delivered through the Boomi offtake. Recent Blue Green Algae (BGA) sampling at Pindari shows that Pindari is at amber alert level. Water deliveries west of Boomi will be grouped together and a shortened release period will be implemented to ensure efficient deliveries during the 218/19 growing season. Planned Supply Interruptions No supply interruptions are currently forecast. Page 2 of 28

21 Aug-17 Oct-17 Nov-17 Dec-17 Jan-18 Feb-18 Mar-18 Apr-18 May-18 Jun-18 Jul-18 Aug-18 Sep-18 Oct-18 Nov-18 Dec-18 Jan-19 Feb-19 Mar-19 Apr-19 May-19 Jun-19 Jul-19 Aug-19 Sep-19 Oct-19 Nov-19 Dec-19 Jan-2 Feb-2 Mar-2 Apr-2 May-2 Jun-2 Jul-2 Gigalitres (GL) Aug-17 Oct-17 Nov-17 Dec-17 Jan-18 Feb-18 Mar-18 Apr-18 May-18 Jun-18 Jul-18 Aug-18 Sep-18 Oct-18 Nov-18 Dec-18 Jan-19 Feb-19 Mar-19 Apr-19 May-19 Jun-19 Jul-19 Aug-19 Sep-19 Oct-19 Nov-19 Dec-19 Jan-2 Feb-2 Mar-2 Apr-2 May-2 Jun-2 Jul-2 Gigalitres (GL) Pindari forecast storage volume - Chance of Exceedance Actual Minimum 99% COE DRY 8% COE Median 5% COE WET 2% COE Glenlyon forecast storage volume - Chance of Exceedance Actual Minimum 99% COE DRY 8% COE Median 5% COE WET 2% COE Page 21 of 28

22 Barwon Darling River System River Flow Status Flows in the river system from Mungindi to Wilcannia are currently at cease to flow. Some rainfall was observed in the past week but that was not significant enough to generate any flow in the Barwon darling system. Predicted Flow Patterns Flows in the river system from Mungindi to Wilcannia are forecast to remain at cease to flow until there is a significant rainfall event. Weir pool levels are expected to continue to fall due to evaporation, town water use and Basic Landholder Rights extractions. Operating Conditions Below are the river management zones and access availability using daily average data to 6 am, these are provided as an indication only and access may have changed during the 24- hour period. Page 22 of 28

23 WaterNSW HYPLOT V133 Output 8/1/218 Period 1 Month 1/1/218 to 1/11/ BARWON MUNGINDI Hour Mean Discharge (ML/d) CP BARWON U/S PRESBURY Hour Mean Discharge (ML/d) CP 4224 MOGIL MOGIL Hour Mean Discharge (ML/d) CP Hour Mean Discharge (ML/d) CP TARA Hour Mean Discharge (ML/d) CP 4221 DANGAR BDGE Hour Mean Discharge (ML/d) CP BOOROOMA Hour Mean Discharge (ML/d) CP GEERA Hour Mean Discharge (ML/d) CP Jan Feb Mar Apr May Jun Jul Aug Sep Oct WaterNSW HYPLOT V133 Output 8/1/218 Period 1 Month 1/1/218 to 1/11/ BREWARRINA Hour Mean Discharge (ML/d) CP BEEMERY Hour Mean Discharge (ML/d) CP DARLING@WARRAWEENA Hour Mean Discharge (ML/d) CP 4253 DARLING@BOURKE TOWN Hour Mean Discharge (ML/d) CP 4254 DARLING@LOUTH Hour Mean Discharge (ML/d) CP 4259 DARLING@TILPA Hour Mean Discharge (ML/d) CP 4258 DARLING@WILC. MAIN C Hour Mean Discharge (ML/d) CP Jan Feb Mar Apr May Jun Jul Aug Sep Oct Page 23 of 28

24 1/1/217 1/12/217 1/2/218 1/4/218 1/6/218 1/8/218 1/1/218 1/12/218 1/2/219 1/4/219 1/6/219 1/8/219 1/1/219 1/12/219 1/2/22 1/4/22 1/6/22 1/8/22 Bega River Storage Status Brogo is currently at 6% of active capacity. Predicted Release Patterns Releases are currently at 25 ML/day via valves and likely to remain around this level during the week. Operating Conditions Regulated conditions are present throughout the system. Around 2mm rainfall has been observed in Bega during the last week. Around 1-5mm rain is forecasted over the week. Maximum temperatures are forecast to be around mid-2 s. Minimums around high-single digit temperatures. Recent BGA sampling at Brogo indicates a green alert level is maintained. 12% Brogo Dam - Forecast Storage Volumes - chance of exceedance (COE) 1% 8% 6% 4% 2% Actual Minimum 99% COE Dry 8% COE Median 5% COE Wet 2% COE % Page 24 of 28

25 Hunter Valley Storage Status Glenbawn Dam is at 63%, while Glennies Creek Dam is at 66%, and Lostock Dam is 11% of active capacity. Predicted Release Patterns Releases from Glenbawn are currently around 22 ML/d and are likely to remain at this level for the current week. Glennies Creek Dam releases are currently around 5 ML/d and are likely to remain the same during the week. Lostock Dam is currently spilling at around 25 ML/d. Operating Conditions Significant rain (average across the valley around 25-5mm) has been observed across the valley in the last week. Some rain (around 1-5mm) is forecasted over the week. Maximum temperatures are forecast to be around high-2 degrees, with minimums around early 1 degrees. Recent BGA sampling at Hunter storages indicates a green alert is maintained at Glenbawn and Glennies Creek and Lostock. Planned Supply Interruptions Nil Page 25 of 28

26 Storage % capacity Storage % capacity Hunter Dams - Forecast Storage Levels -- Chance of Exceedance (COE) 12% 1% 8% 6% 4% 2% % Actual storage level minimum 99% COE DRY 8% COE Median 5% COE 12% Lostock Dam - Forecast Storage Volume - chance of exceedance (COE) 1% 8% 6% 4% 2% Actual minimum DRY 8% COE Median 5% COE WET 2% COE % Page 26 of 28

27 Storage % capacity Toonumbar Dam Storage Status Toonumbar Dam is currently at 89%. Predicted Release Patterns Releases from Toonumbar are currently around 16ML/d and are likely to remain at this level for the current week. Operating Conditions Recent BGA sampling at Toonumbar indicates that a green level is present. 12.% Toonumbar Dam- Forecast Storage Level Chance of Exceedance (COE) 1.% 8.% 6.% 4.% 2.% Actual Minimum 99% COE DRY 8 % COE Median 5% COE WET 2% COE.% Page 27 of 28

28 WaterNSW (Rural) Dam Levels The following table shows the status of water supplies at 8 October 218 River Valley Capacity Current Status Storage Dam, Nearest Town (GL) % of active capacity Active (GL) Weekly change (GL) Comments Supply Issues Likelihood of fill and spill High Security Allocations for 218/19 General Security Est 1/7/18 Border Rivers Glenlyon Dam, Stanthorpe Qld % Releases reduced <2% 1% 1.8% 53% Pindari Dam, Inverell % Releases continue for orders 2% 1% 1.8% 53% Gwydir Valley Copeton Dam, Inverell % Regulated & Planned environmental Namoi Valley releases. <5% 1% % 22% Keepit Dam, Gunnedah % 44 - Releases ceased <2% 1% % 19% Split Rock Dam, Manilla % 53 - Releases for upper Namoi <5% 1% 1% N/A Chaffey Dam, Tamworth 98 49% 5-1 Regulated releases <5% 1% 38% N/A Macquarie Valley Burrendong Dam, Wellington % Environmental and irrigation releases, Restricted access to carryover <2% 1% % 52% Windamere Dam, Mudgee 367 4% Irrigation deliveries <5% 1% % 12% Lachlan Valley Wyangala Dam, Cowra % Environmental & Irrigation deliveries <2% 1% % 62% Carcoar Dam, Carcoar 36 52% 19 - Regulated releases 1% 1% % 67% Murrumbidgee Valley Burrinjuck Dam, Yass % Transparent / translucent releases 2% 95% 7% 22% Blowering Dam, Tumut % Irrigation / environmental deliveries 2% 95% 7% 22% Murray Valley Dartmouth, Mitta Mitta (Vic) % Transfers to Hume N/A N/A N/A N/A Hume Dam, Albury % Irrigation & env and L Vic deliveries <25% 97% % 31% Lower Darling Menindee Lakes, Broken Hill % Drought contingency releases N/A 1% % 15% Hunter Valley Glenbawn Dam, Scone 75 63% Regulated releases 2% 1% 1% 21% Glennies Ck Dam, Singleton % Regulated releases 2% 1% 1% 21% Lostock Dam, Gresford 2 11% 2 1 Spilling 9% 1% 1% N/A Coastal Area Toonumbar Dam, Kyogle 11 89% 1 - Regulated releases 1% 1% 1% N/A Brogo Dam, Bega 9 59% 5 - Regulated flow conditions 1% 1% 3% N/A TOTALS 17, % WaterNSW has water resources in Dartmouth, Hume and Glenlyon Dams. TWS = Town Water Supplies 1 Gigalitre (GL) = 1, Megalitres (ML) 1 ML = 1,, litres For information on WaterNSW (Urban) Dam Levels, follow this link: waternsw.com.au/supply/dam-levels/greater-sydneys-dam-levels Page 28 of 28