Water Availability Report

Transcription

1 Water Availability Report 19 March 2018 Authorised by Dan Berry Manager Water System Operations (02) Table of Contents Overview... 2 System Risks... 2 Climatic Conditions Month Forecast Climatic Conditions... 3 Valley Based Operational Activities... 3 Murray Valley... 5 Lower Darling Valley... 7 Murrumbidgee Valley... 8 Lachlan Valley Macquarie Valley Namoi Valley Gwydir Valley Border Rivers 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 29

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 of 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 19 March 2018 was 51.3% of the total active storage capacity. This resulted in a decrease of 0.8% from last week. The total storage level of urban water supplies on 19 March 2018 was 75.9% of the total storage capacity. This resulted in a decrease of 0.6% from last week. System Risks Connectivity of flows in the Barwon Darling system continues from Mungindi to Bourke Weir pool, while cease-to-flow continues from Bourke to Menindee. Inflows from the Moonie River and Culgoa system are expected to refill the Bourke Weir pool within the next week and extend to at least Tilpa. Menindee Lakes have fallen below the 480GL 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. Drought contingency measures (block releases) will be needed in the Namoi and Gwydir valleys to deliver the small volumes remaining in customer accounts if conditions remain dry in 2018/19. Cease to flow conditions will now start in the Gwydir and Lower Namoi Valleys. Page 2 of 29

3 Climatic Conditions There was negligible rainfall during the week, except for isolated falls of 5 50mm around the Sydney Metropolitan area. Figure 1 - Weekly rainfall totals for New South Wales (w/e 19 March 2018) A low pressure trough is lingering over northeast New South Wales today, as a high pressure ridge develops over the west. A strong high pressure system is expected to build over the southern Tasman Sea during Tuesday and Wednesday, pushing a new ridge along the New South Wales coast. This should result in good rainfall to the east of the state, with minor falls over the rest of the state. Figure 2a First 4 day Forecast (19 22 Mar 18) Figure 2b Following 4 day forecast (23 26 Mar 18) Page 3 of 29

4 3 Month Forecast Climatic Conditions The April to June outlook, issued 15 March 2018, shows southeast NSW is likely to be wetter than average. April is slightly more likely to be wetter than average near the east coast of NSW. Days are likely to be warmer than average for parts of southeast Australia Nights are likely to be warmer than average for New South Wales. The La Niña in the tropical Pacific Ocean has ended, and ENSO neutral conditions now prevail. With neutral conditions also in the Indian Ocean, there is no strong push towards broad scale wetter or drier conditions for much of the country. Figure 3-3 month rainfall forecast Page 4 of 29

5 Valley Based Operational Activities Murray Valley Storage Status Hume Dam is currently at 43% of active capacity, releasing about 13,400 ML/d. Predicted Release Patterns Releases from Hume Dam are likely to vary to meet changing irrigation demands. The flow at downstream Yarrawonga Weir is approximately 8,900 ML/d and is likely to remain steady to meet the downstream demands. Stevens Weir is likely to be maintained at the current level of about 4.63 m, primarily to manage the upstream Wakool Canal offtake water level. The flow at downstream Stevens Weir is currently about 1,100 ML/d, and the flow is expected to remain steady. Environmental watering events in the Wakool / Yallakool and Colligen systems have ceased since 6 March due to algal alerts. Edward River Offtake is currently about 1,600ML/d. Gulpa Creek Offtake is 350ML/d, which is the normal operational level. Edward River Escape of the Mulwala Canal is being used to meet all the Wakool Canal orders. The Escape orders are about 950 ML/d. Operating Conditions The 15 March 2018 AWD review saw an increase of 2% increase to general security category. The current allocation to general security licences is 51%. Diversions into Colligen Creek (170ML/d), Yallakool Creek (280ML/d) and Wakool River offtake (60ML/d) will be managed as per the system demands. Flow at Moulamein is currently about 530 ML/d and is likely to increase to about 1,200ML/day over the next week. Flow at Mallan School is currently about 120ML/d and is likely to reduce to 90ML/day over the next week. Inflows from Murrumbidgee River are about 275 ML/d at Balranald, and likely to vary in line with minor system operational surplus in the next week. Lake Victoria is currently holding about 303 GL or 35% active capacity. End of system flows to South Australia is currently about 6,900 ML/d. Potential Blue Green Algae issues. o Hume Dam: Results for 07/03 were again at Green Alert levels at each lake site. The lake is now at Green Alert and will return to routine monthly sampling. Diatoms are currently dominant in the lake. Page 5 of 29

6 o o o o A Red Alert has been lifted for Edward River at Deniliquin following two weeks of results below triggers. A further result below Red Alert levels at Gulpa Creek at Mathoura is required to lift the alert. Results for Murray River at Picnic Point and Moama were relatively low. Red Alert remains in place for Lake Victoria, Darling River at Wilcannia, and Darling River at Pooncarie and Burtundy For more information visit: Planned Supply Interruptions: None. Page 6 of 29

7 Lower Darling Valley Storage Status The lakes currently hold an active volume of about 198 GL or about 12% of active capacity. The total storage is about 284 GL. Lake Menindee has been dry since 6 Feb Predicted Release Patterns Release from Lake Pamamaroo is about 300ML/d, primarily to meet the flow targets of about 200ML/d at Weir 32 and at least 20ML/d at Burtundy. Release from Lake Cawndilla outlet to Redbank Creek ceased on 19/3/2018 as there is no further irrigation demand. Operating Conditions The net evaporation loss over the last week was about 7,900 ML. The average pan evaporation rate at Menindee over the last week was about 10.mm/d, which is about 17% higher than the climatic average for the month of March. The total storage of Menindee Lakes reached the 480GL trigger for NSW control of the lakes on 16 December The releases from the storages will be managed as per the Lower Darling Annual Operations Plan until the storage volume next exceeds 640GL. For more information visit: data/assets/pdf_file/0006/129831/lower-darling-operational-plan-december-2017.pdf The current flow rate at Burtundy is about 38 ML/d and is expected to trend to 20ML/day over the next week. As planned a temporary bank has been installed between Lake Wetherall and Lake Tandure. The pumping to transfer water into Lake Wetherall as part of the measures to reduce evaporation losses is set to start. 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 Results to the 5th March show a red alert at Lake Wetherill Site 3 o The Wetherell sites 1,2,4 and Tandure site 8 are now at amber alerts o Darling R. at Weir 32 and Darling R. Pumping Station at Menindee are at amber alert o Darling R at Pooncarrie and Burtundy are at Red Alert. o For more information visit: Planned Supply Interruptions Nil Page 7 of 29

8 Murrumbidgee Valley Storage Status Burrinjuck Dam is currently at about 41% releasing about 3,000 ML/d. Blowering Dam is about 42% releasing about 1,100 ML/d. Predicted Release Patterns The current release rates from Burrinjuck Dam will be decreased in steps to the minimum transparent releases (450 ML/d) this week. From then on the system demand would primarily be met from Blowering Dam. It is estimated that the release from Blowering Dam will be around 3,000ML/d for the next couple of weeks. The increased proportion of releases from Burrinjuck Dam over the last eight weeks has reduced the chance of Burrinjuck Dam spilling by September 2018 to less than median conditions. The current diversion into the Yanco Creek is about 650 ML/d. The delivery through Coleambally escapes averages about 200 ML/d to meet demands in the Yanco Creek / Billabong system. At the Beavers Creek Offtake the flows are about 250 ML/d. The current flow at Kywong is around 100 ML/d. The operational flow target to end of April at Kywong is 60 ML/d. Operating Conditions The 15 March 2018 AWD review saw an increase of 4% to 38% for general security. The Water Operations team is working with major customers to review water orders on a day to day basis to forecast the irrigation demands. As the focus is on avoiding system shortfalls, releases from head water storages are targeting advance water orders while maximising the use of en-route reregulation storages. Due to over ordering there is some system surplus, which is being captured in the re-regulatory storages at. Bundidgerry and Tombullen. Re-regulation storages are being actively used. Bundidgerry is currently about 85%, Tombullen at about 30%, Hay Weir at about 70%, Maude Weir at about 50% and Redbank Weir at about 50%. Over the next week the above re-regulation storages, except Tombullen, will continue to remain at current levels. Tombullen is expected to rise to about 50%. The weather has generally been very dry in the irrigation areas. Watering for rice and corn is largely complete. A small demand exists for watering soy and pasture, while the demand for cotton is variable. The water orders for all summer crops have slowed down in the Murrumbidgee as expected. The water demand is picking up in the Yanco Billabong system mainly for pre-watering winter pastures. The current system operations target of 0.85m at Darlington Point will end by next week. The water levels at Darlington Point gauge is likely to fall to about 0.5m with flows dropping while meeting the lower demands downstream of Gogeldrie Weir. Page 8 of 29

9 The river sections downstream of Gogeldrie Weir to the Murray confluence may experience low river levels, particularly between Gogeldrie Weir to the influence of the Hay Weir, and downstream of Redbank Weir to the Murray confluence. Customers should take the necessary steps to adjust their pumping activities accordingly and monitor the river level closely. Flows at Balranald are currently about 270 ML/d and are expected to remain above the end of system flow target (180ML/d) in order to maintain a steady level at Balranald Weir. At this time, regular monitoring of the Balranald Weir pool will occur and operations adjusted as necessary in an effort to maintain the weir pool. A small additional flow from the current system surplus will be maintained at Balranald to assist the fishing competition over the coming weekend. The current flow at Darlot is about 116ML/d and is likely to steadily increase in line with the downstream demands. Inter Valley Transfer (IVT) account from Murray to Murrumbidgee closed on 20 October The current balance is 6.8 GL. Potential Blue Green Algae issues. o o o o o o o o o Blowering Dam: Latest results (14/02) showed only small counts of benign cyanobacteria (Aphanocapsa sp.). Biomass has increased slightly from the January sampling run but is generally low and not of concern. No cyanobacteria were detected downstream and the storage remains at green alert. Burrinjuck Dam: February sampling (28/02) saw relatively low numbers of algae with diatoms and green alga dominant at most sites. Goodhope was again uncharacteristically higher although much lower than January. No increased sampling has been actioned as yet. The latest blue-green algal results for the Murrumbidgee River at Maude Weir Buoy as well as Weir Pool sites that include Hay Weir Boy and Leonard Street Sites, indicate that the blue-gre cell numbers are lower than the red alert range. According to blue-green algal management however, the sites remain on Red alert until two consecutive laboratory results indicate that th levels have reduced to lower than red alert level. New water samples were taken for analysis a sites this week. Results for these samples are expected to be available by this week. Amber alerts are current for Burrinjuck Dam at Goodhope, Murrumbidgee River at Carrathool and Redbank Weir Buoy Sites The results further indicate that Burrinjuck Dam at Woolgarlo, Blowering Station 1 (Dam Wall) and Tombullen Outlet at Weir D/S are on Green alert Billabong Creek at Walbundrie (14/03) and Jereldrie (13/03) have green alert Samples from other sites have no alert. Note: The alert levels apply to non-consumptive or recreational contact. Drinking water safety thresholds are much more stringent For more information visit: Planned Supply Interruptions None. Page 9 of 29

10 Burrinjuck Dam Forecast Storage Capacity Updated end-february End of Month Storage (GL) Extreme dry scenario (99%) Dry Scenario (80%) Average scenario (50%) Wet scenario (20%) Actual Jul-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 * Including Snowy releases Blowering Dam Forecast Storage Capacity Updated end-february Jul-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 End of Month Storage (GL) Jun-19 Extreme dry scenario (99%) Dry Scenario (80%) Average scenario (50%) Wet scenario (20%) Actual * Including Snowy releases Page 10 of 29

11 Lachlan Valley Storage Status Carcoar Dam is at 63% and releases have averaged about 50 ML/d during the last week. Wyangala Dam is at 69% and releases have averaged about 2,500 ML/d during the last week. Predicted Release Patterns The releases have increased to around 60 ML/d from Carcoar Dam due to increased demand. The releases from Wyangala Dam have reduced to 750ML/d and are expected to remain steady over the week. The Lower Lachlan releases at Brewster have been averaging 450ML/d to meet irrigation demands and to meet the minimum flow target. Demand is predicted to reduce further in the coming weeks as the final cotton watering takes place. Operating Conditions As releases from Wyangala Dam are receding, a minimum flow target of 350 ML/d has been set at downstream Jemalong Weir to ensure adequate flows into Island Creek and Wallamundry Ck system to meet demand for autumn watering. It is estimated that a combined dam and tributary inflow volume in excess of 36,000 ML was required in March before a further allocation could be made in the Lachlan River. Inflows to Wyangala Dam in March to date have totalled 3,500 ML. Lake Cargelligo storage is currently at 51% and it is planned to gradually draw down the storage level to 40% in autumn to maximise the capture of any surplus flows from tributaries. Landholders along the foreshores of Lake Cargelligo are advised to fill their stock and domestic storages prior to the drawdown in lake level. As of 13 th March 2018, Lake Brewster is at 3% holding about 4 GL totally with about 3 GL in the main storage. Latest BGA samples from Lake Brewster show that Willandra Weir, the Outlet Channel and Lake Brewster Regulator C are on red alert. Lake Cargelligo Outlet and Boatshed are on amber alert. As of 12 th March no more water has been drawn from Lake Brewster storage as the remaining water is set aside to be delivered as Environmental Contingency Allowance (ECA) from Lake Brewster. Consequently releases from Lake Cargelligo have been managed to meet more of the demand in the lower Lachlan. Delivery of licenced environmental water to replenish the outflow wetlands has commenced on 12 March. Flows of about 150 ML/d are being directed via inlet channel from Brewster Weir to raise water levels in the lake s outlet channel and then spill into the outflow wetlands. The next delivery of S&D replenishment flows in the lower Lachlan will be in late autumn Planned Supply Interruptions Page 11 of 29

12 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 29

13 Macquarie Valley Storage Status Burrendong Dam is currently at 39% and Windamere Dam is at 43% capacity. Predicted Release Patterns Currently releases from Burrendong are around 250 ML/d and are planned to be around 200 ML/d for the rest of the week due to reducing irrigation demand. Releases from Windamere are currently around 50ML/d and are planned to stay steady for the rest of the week. Operating Conditions All the current releases from Burrendong Dam are for irrigation and town water demand and minimum flow targets. It is estimated that an additional 185 GL of inflow is required in March to trigger an increment in Available Water Determination. Inflows to Burrendong Dam from 1 st of March to date were about 8.5 GL. It is forecasted that a total of less than 400 GL of licenced water may be extracted for irrigation and environment this water year. Algal sampling results from 7 th Feb 2018 at Burrendong shows a minor detection downstream however this does not appear to relate to upstream results. The storage remains at green alert. Sampling results from 6 th March 2018 at Windamere shows Red alert levels of BGA at the dam wall. The storage is now at Red alert. The position of the trash rack at Windamere Dam is currently 9-12 m below the surface. Deep water diving work at the intake tower to reinstate the CWP temperature curtain has been completed before Christmas. All 8 guide wire cables have been installed to the anchors on the floor of the dam, in readiness for curtain reinstatement in Carryover evaporation reduction was applied to remaining carryover balances in HS and GS subaccounts in Macquarie and Cudgegong Rivers for December quarter. A 1.3% reduction was applied to Macquarie River Water Source and a 1.0% reduction was applied on Cudgegong River water source. Carryover balances in EWA incurred the 1.3% reduction. The Dept of Industry (water) water allocation statement (WAS) dated 14 March 2018 confirmed that the forecast usage in 2018/19, including environmental watering plans, is deliverable from the stored water currently in Burrendong and Windamere Dams. A bulk water transfer from Windamere Dam may be required, commencing in January 2019 if conditions remain dry. Stock and domestic replenishment flows will be scheduled for delivery in late autumn/winter The timing of deliveries thereafter in 2019 will depend on rainfall events, dam inflows, and contributions from downstream tributaries. Page 13 of 29

14 Planned Supply Interruptions There are no planned supply interruptions to be undertaken for this week. Page 14 of 29

15 Namoi Valley Storage Status Keepit Dam is at 14%, Split Rock Dam is at 16% and Chaffey Dam is at 72% of active capacity. Predicted Release Patterns A release of water for the Commonwealth Environmental Water Holder from Keepit Dam has begun. The release is to maintain stream connectivity for the upper section of the Namoi River to Narrabri. Releases to maintain this connectivity are forecast to be about ML/d. Split Rock Dam is releasing around 35 ML/d to deliver about 15 ML/d to Upper Namoi water users. This will increase to approximately 45ML/day as tributary flows reduce. Releases are expected to remain relatively stable for the next week. Peel releases have increased to 145ML/day and are forecast to stay around 130 to 140ML/ for the next week. Demand has been split evenly between Tamworth City of approximately 40ML/day and industry use of around 40ML/day. Operating Conditions There was no rainfall during the past week with temperatures ranging from low to high 30 s. There is less than 5mm of rain forecast for the next week, though temperatures are to reduce to low 30 s. Irrigation demand in the lower Namoi has ceased. Ongoing intermittent releases from Keepit will be required to satisfy mining requirements in the upper river sections, although these can be tied in with environmental connectivity flows in the short term. It is likely that some additional environmental deliveries may commence in April/May in both the Peel and Lower Namoi Valleys. Recent sampling for BGA indicates that Chaffey, Split Rock and Keepit remain at amber alert. Deliveries below Bugilbone and Rossmore gauges have ceased in line with the agreed strategies to reduce system losses. The replenishment flow is currently underway in the Pian Creek system and flows have reached Waminda gauging station. Water will be available for these stock and domestic requirements for the next couple of weeks. Under minimum inflows and forecast demand the combined storage levels of Split Rock and Keepit are forecast to be below 120GL by May this year. If inflow is better than minimum and or demand is less than forecast the combined storage may be above 120GL. If the combined storage is below 120GL by early May, no end of system flows will be undertaken, if above 120GL end of system flows will be required to be delivered while the combined storage is above 120GL. Water deliveries have ceased in the first week of March 2018, and if conditions remain dry, remaining water in licences will be delivered via a complete block release strategy throughout 2018/19. It is likely that only one release will occur during the winter months and up to three releases during spring and summer below Mollee Weir. Release upstream of Mollee will occur every 6 to 8 weeks. Page 15 of 29

16 Lower Namoi customers and landholders are encouraged to ensure that they have adequate stock and domestic supplies while there are current flows available as cease to flow conditions may now begin in the western reaches as well as the upper reaches. Supply on demand will continue for the Upper Namoi and the Peel Valley, though customers will notice reduced river levels. Planned Supply Interruptions Mollee fish way is currently unavailable due to infrastructure failure. Planning is underway to determine the appropriate time to undertake inspections of Mollee fish way as well as Mollee and Gunidgera weir gates. 450 Keepit forecast storage volume Gigalitres (GL) Mar-17 May-17 Jun-17 Jul-17 Aug-17 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 Feb-19 Mar-19 Apr-19 May-19 Jun-19 Jul-19 Aug-19 Sep-19 Oct-19 Nov-19 Dec-19 Jan-20 Feb-20 Actual Minimum 99% COE DRY 80% COE Median 50% COE WET 20% COE Page 16 of 29

17 300 Split Rock - forecast storage volume Gigalitres (GL) Mar-17 May-17 Jun-17 Jul-17 Aug-17 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 Feb-19 Mar-19 Apr-19 May-19 Jun-19 Jul-19 Aug-19 Sep-19 Oct-19 Nov-19 Dec-19 Jan-20 Feb-20 Actual Minimum 99% COE DRY 80% COE Median 50% COE WET 20% COE 100 Chaffey Dam - forecast storage volume Mar-17 May-17 Jun-17 Jul-17 Aug-17 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 Feb-19 Mar-19 Apr-19 May-19 Jun-19 Jul-19 Aug-19 Sep-19 Oct-19 Nov-19 Dec-19 Jan-20 Feb-20 actual Minimum 99% COE DRY 80% COE Median 50% COE WET 20% COE Page 17 of 29

18 Gwydir Valley Storage Status Copeton Dam is at 29% of active capacity. Predicted Release Patterns Releases have been made to satisfy the pecan farm requirements, and will continue until Wednesday 21 st at the current rate of 130ML/d and then reduce to approximately 30ML/d. Operating Conditions No rainfall was recorded over the past week and temperatures ranged from low 30 s to high 30s and are forecast to remain at the high end until mid-week when they will reduce to low 30 s. Summer crop demand has ceased and it is likely only minor releases from Copeton will be required to satisfy pecan farm requirements in the upper reaches for the next month. It is possible that some additional environmental deliveries may commence in April/May. Recent Blue Green Algae (BGA) sampling at Copeton shows a continuation of amber alert. Consultation with customers in relation to limited water deliveries next season has begun. It is forecast that there will be less than 50GL available for industry production at the end of 2018 summer growing season and approximately 145GL of environmental water. If conditions remain dry the delivery of remaining volumes will need to be managed so that essential supplies can be met going forward. As such block releases will be required on western effluent streams and discussions will continue with customers around delivery options through winter. Customers and landholders are encouraged to ensure that they have adequate stock and domestic supplies while there are current flows available as river flows will start to cease during March. Planned Supply Interruptions No supply interruptions are expected. Page 18 of 29

19 1400 Copeton - forecast storage volume Gigalitres (GL) Mar-17 May-17 Jun-17 Jul-17 Aug-17 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 Feb-19 Mar-19 Apr-19 May-19 Jun-19 Jul-19 Aug-19 Sep-19 Oct-19 Nov-19 Dec-19 Jan-20 Feb-20 Actual Minimum 99% COE DRY 80% COE Median 50% COE WET 20% COE Page 19 of 29

20 Border Rivers Storage Status Pindari Dam is at 60%. Glenlyon is at 56%. Predicted Release Patterns Pindari releases reduced to 20ML/d on Monday 19 March. Releases are expected to maintain at this level for the next week. Glenlyon releases have increased as tributary flows have reduced, releases will be reduced from 500ML/day to approximately 100ML/day on Tuesday 20 March, releases will continue until the growing season ceases in the top end or there is another rainfall event. Operating Conditions No rainfall was recorded over the past week and temperatures ranged from low 30 s to high 30s and are forecast to remain at the high end until mid-week when they will reduce to low 30 s. Large irrigation demand in the Border has ceased and it is likely only minor releases from Pindari and Glenlyon will be required to satisfy the smaller irrigation enterprises east of Goondiwindi. It is possible that some small environmental deliveries may commence in April/May. End of system flows have increased due to rainfall events several weeks ago. Recent BGA sampling at Pindari maintain the amber alert. Customers and landholders are encouraged to ensure that they have adequate stock and domestic supplies while there are current flows available as river flows will start to cease during March. Planned Supply Interruptions Boggabilla weir will be lowered to the off season operating level from the 1 of April, this means that the weir operating level will be at approximately 40% of the full supply level. Page 20 of 29

21 Pindari forecast storage volume Gigalitres (GL) Mar-17 May-17 Jun-17 Jul-17 Aug-17 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 Feb-19 Mar-19 Apr-19 May-19 Jun-19 Jul-19 Aug-19 Sep-19 Oct-19 Nov-19 Dec-19 Jan-20 Feb-20 Actual Minimum 99% COE DRY 80% COE Median 50% COE WET 20% COE 300 Glenlyon forecast storage volume Gigalitres (GL) Mar-17 May-17 Jun-17 Jul-17 Aug-17 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 Feb-19 Mar-19 Apr-19 May-19 Jun-19 Jul-19 Aug-19 Sep-19 Oct-19 Nov-19 Dec-19 Jan-20 Actual Minimum 99% COE DRY 80% COE Median 50% COE WET 20% COE Page 21 of 29

22 Barwon Darling River System River Flow Status Flows at Mungindi have averaged 273 ML/d during the past week due to end of system flow requirements and small inflows from the weir river. Flows will reduce to around 100ML/day for the next 7 days. A total flow event volume of approximately 7,200ML has entered the Barwon River from the Moonie River. These inflows are now reducing and a total flow event volume of around 8,000ML is expected. Flows from the Carole/Gil Gil have averaged 150ML/d and are expected to reduce to less than 10ML/day in the next 7 days. Flows from the Mehi have averaged around 24 ML/day for the past week and are expected to be less than 5ML/day for the remainder of the week. Flows from the lower Namoi have averaged around 24ML/d as a result of the Pian replenishment flow, these flows will continue to reduce and it is expected that cease to flow conditions will be present at the bottom of the Namoi. Walgett weir is currently full and spilling 800ML/day. A total of 9,400ML has passed Walgett during the past 8 weeks. Flows will increase over the coming week as flows from the Moonie River pass through the river at Walgett. No inflows from the Macquarie valley are current or are expected in the coming weeks without additional rainfall. Flow connectivity is present from Mungindi to Bourke Weir pool. Bourke Weir pool is currently rising and is expected to spill within the next 7 days. While flows have reduced back to approximately 70ML/day at Brewarrina Weir, these flows will increase in the next 4 to 5 days with increased flows from the Moonie starting to arrive. It is now expected that flows in the Culgoa River will make it to the Darling. Flows peaked at St George at approximately 13,000ML/d on the 10/03/2018 with a total flow volume of approximately 54,000ML. This has equated to a flow peak of approximately 3,220ML/d at the Brenda Gauge just inside the NSW Border, with a forecast volume of between 10,000ML and 13,000ML. It is expected that total flow from the Culgoa and Bokhara river system will be in the range of 6,000ML to 10,000ML and will start to reach the Darling system between 23 and 25 March. It is likely that flow connectivity may be restored down to Tilpa over the coming weeks. Preliminary forecast indicate that there may be a small volume of water from the Warrego system. Flows peaked at Wyandra Gauge upstream of Cunnamulla in QLD on 12 March at just under 18,000ML/d, with a total flow of approximately 80,000ML. Early forecasts indicate that there could be 1,000ML to 4,000ML reach the Darling in early to mid-april. Predicted Flow Patterns Connectivity is likely to extend down to at least Tilpa and potentially to beyond Wilcannia, further advice will be provided as the volumes and losses being experienced become clearer. Page 22 of 29

23 Operating Conditions A section 324 Temporary Water Restriction order took effect on Friday 9 March which restricts access for A, B and C class access licences until 31 March WaterNSW will continue to assess current and forecast flows and will provide appropriate advice. Cease to flow conditions are present at multiple locations, Bourke approximately 65 Days, Louth approximately 71 Days and Wilcannia approximately 59 days (Cease to flow is determined as 10ML/day or below). Regional councils are planning to reduce water restrictions as weir pools fill and commence to spill, though it will be an additional month before flows have worked through the system. Below are the river management zones that currently had access availability from Mar 2018 using 6am flow data, these are provided as an indication only and may have changed during the 24 hour period. A Section 324 Temporary Water Restriction Order is in place that restricts access for A, B and C class licences from the 9 March, and although flow triggers may be reached, access is restricted while the Order is in place. Page 23 of 29

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25 Bega River Storage Status Brogo is back under regulated flow conditions and is currently 99% of active capacity. Predicted Release Patterns Releases up to about 30 ML/d via valves have continued and will likely remain stable around this level for the next week. Operating Conditions With no further rainfall throughout the past week, combined with and extreme temperatures and bush fires, stream flows continue to recede. Access to uncontrolled flow has ceased in all sections. Temperatures are forecast to reduce back to low 20 s with chances of rainfall toward the end of the week. Recent BGA sampling at Brogo indicates a green alert level is maintained Brogo Dam - Forecast Storage Levels 140% 120% Storage % capacity 100% 80% 60% 40% 20% 0% 1/02/12 1/06/12 1/10/12 1/02/13 1/06/13 1/10/13 1/02/14 1/06/14 1/10/14 1/02/15 1/06/15 1/10/15 1/02/16 1/06/16 1/10/16 1/02/17 1/06/17 1/10/17 1/02/18 1/06/18 1/10/18 1/02/19 1/06/19 1/10/19 1/02/20 Actual Dry 80% COE Median 50% COE Wet 20% COE Minimum 99% COE Page 25 of 29

26 Hunter Valley Storage Status Glenbawn Dam is at 76%, while Glennies Creek Dam is at 69%, and Lostock Dam is 80% (2% increase) of active capacity. Predicted Release Patterns Releases at Glenbawn Dam are currently 178ML/d, though are expected to increase to 750ML/d on Tuesday 20 March in line with power station demand. Glennies Creek Dam releases remain relatively stable around 50 to 80 ML/d. Lostock Dam releases has remained at about 10ML/d, and it is unlikely that these will increase with rain forecast between 50 and 100mm.. Operating Conditions Additional rainfall throughout the past week was limited, stream flows in the Paterson from previous rainfall continue to recede. Recent BGA sampling at Hunter storages indicates a green alert is maintained at Glenbawn and Glennies Creek dam whilst Lostock remains at amber alert. Rain is forecast from 20 to 100mm across the Hunter valley. Planned Supply Interruptions A trash rack change is required at Glennies Creek which will be scheduled dependant on staff availability. Page 26 of 29

27 120% Hunter Dams - Forecast Storage Levels % 100% Storage % capacity 80% 60% 40% 20% 0% 1/02/12 1/06/12 1/10/12 1/02/13 1/06/13 1/10/13 1/02/14 1/06/14 1/10/14 1/02/15 1/06/15 1/10/15 1/02/16 1/06/16 1/10/16 1/02/17 1/06/17 1/10/17 1/02/18 1/06/18 1/10/18 1/02/19 1/06/19 1/10/19 1/02/20 Actual Dry 80% COE Median 50% COE Wet 20% COE Minimum 99% COE % Lostock Dam - Forecast Storage Level % Storage % capacity 80.00% 60.00% 40.00% 20.00% 0.00% 1/02/12 1/05/12 1/08/12 1/11/12 1/02/13 1/05/13 1/08/13 1/11/13 1/02/14 1/05/14 1/08/14 1/11/14 1/02/15 1/05/15 1/08/15 1/11/15 1/02/16 1/05/16 1/08/16 1/11/16 1/02/17 1/05/17 1/08/17 1/11/17 1/02/18 1/05/18 1/08/18 1/11/18 1/02/19 1/05/19 1/08/19 1/11/19 1/02/20 Actual Dry 80% COE Median 50% COE Wet 20% COE Drought Page 27 of 29

28 Toonumbar Dam Storage Status Toonumbar Dam 101% and decreasing. Predicted Release Patterns Passing flows of approximately 90ML/d, uncontrolled spill will continue for the next week. Operating Conditions Recent BGA sampling at Toonumbar has reduced to amber alert. 120% Toonumbar Dam- Forecast Storage Level 100% Storage % capacity 80% 60% 40% 20% 0% 1/02/12 1/06/12 1/10/12 1/02/13 1/06/13 1/10/13 1/02/14 1/06/14 1/10/14 1/02/15 1/06/15 1/10/15 1/02/16 1/06/16 1/10/16 1/02/17 1/06/17 1/10/17 1/02/18 1/06/18 1/10/18 1/02/19 1/06/19 1/10/19 1/02/20 Actual Dry 80% COE Median 50% COE Wet 20% COE Minimum 99% COE Page 28 of 29

29 WaterNSW (Rural) Dam Levels The following table shows the current status of water supplies at 19 March 2018 River Valley Capacity Current Status Storage Dam, Nearest Town Border Rivers (GL) % of active capacity Active (GL) Weekly change (GL) Comments Likelihood Allocations for 2017/18 Supply Issues of fill and spill High Security General Security 1/7/17 Glenlyon Dam, Stanthorpe Qld % Releases recommenced <20% 100% 19.62% 90% Pindari Dam, Inverell % Minimum releases 20% 100% 19.62% 90% Gwydir Valley Copeton Dam, Inverell % Pecan farm deliveries <5% 100% 17.59% 60% Namoi Valley Keepit Dam, Gunnedah % 57-2 Environmental deliveries <20% 100% 7% 80% Split Rock Dam, Manilla % 63 0 Releases for upper Namoi users only <5% 100% 100% N/A Chaffey Dam, Tamworth % 72-1 Regulated releases steady 50% 100% 100% N/A Macquarie Valley Burrendong Dam, Wellington % Releases reducing 20% 100% 38% 73% Windamere Dam, Mudgee % Irrigation deliveries <5% 100% 38% 137% Lachlan Valley Wyangala Dam, Cowra % Releases reducing 20% 100% 2% 108% Carcoar Dam, Carcoar 36 63% 23 0 Irrigation deliveries 10% 100% 0% 95% Murrumbidgee Valley Burrinjuck Dam, Yass % Irrigation releases 50% 95% 38% 27% Blowering Dam, Tumut % Irrigation releases <20% 95% 38% 27% Murray Valley Dartmouth, Mitta Mitta (Vic) % Minimum releases N/A N/A N/A N/A Hume Dam, Albury % Irrigation releases <25% 97% 51% 44% Lower Darling Menindee Lakes, Broken Hill % Minimum releases N/A 100% 100% 77% Hunter Valley Glenbawn Dam, Scone % Regulated releases primarily power station use 20% 100% 100% 28% Glennies Ck Dam, Singleton % Regulated releases 20% 100% 100% 28% Lostock Dam, Gresford 20 80% 16 0 Coastal Area Minimum releases downstream tribs reducing 90% 100% 100% N/A Toonumbar Dam, Kyogle % 11-0 Dam spilling - reducing 100% 100% 100% N/A Brogo Dam, Bega 9 99% 9-0 Regulated flow conditions 100% 100% 75% N/A TOTALS 17, % WaterNSW has water resources in Dartmouth, Hume and Glenlyon Dams. TWS = Town Water Supplies 1 Gigalitre (GL) = 1,000 Megalitres (ML) 1 ML = 1,000,000 litres For information on WaterNSW (Urban) Dam Levels, follow this link: Page 29 of 29