Water Availability Report

Transcription

1 Water Availability Report Authorised by Dan Berry Manager Water System Operations (02) April 2018 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... 5 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 32

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 2 April 2018 was 50.3% of the total active storage capacity. This resulted in a decrease of 0.5% from last week. The total storage level of urban water supplies on 2 April 2018 was 75% of the total storage capacity. This resulted in a decrease of 0.8% from last week. System Risks The Temporary Water Restrictions have been extended in the Barwon Darling system downstream of Boorooma to reinstate connectivity of flow to Wilcannia and Menindee. Connectivity of flows continues from Mungindi to Louth. Cease-to-flow continues from downstream of Louth though flow connectivity is expected to occur over the coming weeks to Wilcannia. 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 have commenced in parts of the Gwydir and Lower Namoi Valleys. Page 2 of 32

3 Climatic Conditions FIGURE 1 - WEEKLY RAINFALL TOTALS FOR NEW SOUTH WALES (W/E 3 APRIL 2018) A moist onshore flow generated showers along north-eastern New South Wales. This brought rain total of up to 10 to 50mm along north coast. Little or no rainfall observed along inland part of the state. Figure 2a First 4 day Forecast (03-6 April 18) Figure 2b Following 4 day forecast (6 April 10 Apr 18) Page 3 of 32

4 3 Month Forecast Climatic Conditions The April to June outlook, issued 29 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 - THREE-MONTH RAINFALL OUTLOOK Page 4 of 32

5 Valley Based Operational Activities Murray Valley Storage Status Hume Dam is currently at 38% of active capacity, releasing about 13,000 ML/d. Predicted Release Patterns Releases from Hume Dam are likely to marginally vary in line with downstream environmental/irrigation demands. Planning is underway to lower Lake Mulwala in late autumn and winter; the draw down is aimed at managing invasive water weed and also to undertake works on the lake foreshore. The flow at downstream Yarrawonga Weir is approximately 8,750 ML/d which is near the limit of channel capacity through the Barmah Choke. Edward River Offtake is currently near the channel capacity limit of 1,600ML/d. Gulpa Creek Offtake is near the channel capacity limit of 350ML/d. Edward River Escape of the Mulwala Canal is being used to meet all the Wakool Canal orders. The Escape orders are about 600 ML/d. Stevens Weir is likely to be maintained at the current level of about 4.63m. The flow at downstream Stevens Weir is currently about 760 ML/d to assist meeting demands in the Lower Murray and the flow is expected to vary between 650 and 900 ML/d. Operating Conditions Diversions into Colligen Creek (350ML/d), Yallakool Creek (450ML/d) and Wakool River offtake (55ML/d) will be managed as per the environmental demands. Flow at Moulamein is currently about 1,170 ML/d and is likely to remain relatively steady over the next week. Flow at Mallan School is currently about 120ML/d and is likely to remain relatively steady over the next week. Inflows from Murrumbidgee River are about 280 ML/d at Balranald, and likely to gradually reduce before stabilising at about 250 ML/d. Lake Victoria is currently holding about 274 GL or 26% of active capacity. End of system flows to South Australia is currently about 6,100 ML/d. Page 5 of 32

6 Potential Blue Green Algae issues. o o o o Hume Dam: Results for 19/03 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. Red alerts continue for the Lake Victoria outlet regulator. Edward R. at Deniliquin and Moulamein are at Green alert level For more information visit: Planned Supply Interruptions: Lowering of Lake Mulwala is being planned for the late autumn and winter season. However, it is not expected to impact the water supply to meet the forecast demands, which are expected to be low with end of irrigation season for MIL. Page 6 of 32

7 Lower Darling Valley Storage Status The lakes currently hold an active volume of about 182 GL or about 11% of active capacity. The total storage is about 256 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 has now ceased. Operating Conditions The net evaporation loss over the last week was about 5,600ML. The average pan evaporation rate at Menindee over the last week was about 7.4mm, which is about 15% lower 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 63ML/d and is expected to remain relatively steady over the next week. As planned, a temporary bank has been installed between Lake Wetherall and Lake Tandure. Pumping started on 25 March 2018 to transfer water at 160ML/day into Lake Wetherall as part of the measures to reduce evaporation losses from Lake Tandure. The pumping has temporarily been suspended due to technical issues at the pumping site. 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 12 March show a red alert at Lake Wetherill Site 3 and Tandure site 8 o The Wetherell sites 1,2,4 and are now at amber alerts o Darling R. at Weir 32 and Darling R. Pumping Station at Menindee are at green alert o Darling R at Pooncarie and Burtundy are at Red Alert. o For more information visit: Page 7 of 32

8 Planned Supply Interruptions Nil Page 8 of 32

9 Murrumbidgee Valley Storage Status Burrinjuck Dam is currently at about 40% releasing about 450 ML/d. Blowering Dam is about 43% releasing about 2,600 ML/d. Predicted Release Patterns While the required release from Burrinjuck Dam as per the Plan rules are about 300ML/day, the current releases are being managed to maintain the minimum flow to operate the Hydro Electric Power Station. Hence the releases are likely to stay around 450ML/day. The system demand is primarily being met from Blowering Dam. It is estimated that the release from Blowering Dam would vary between 1,800 and 3,000ML/d for the next couple of weeks. The current diversion into the Yanco Creek is about 500 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 100 ML/d. The current flow at Kywong is around 20 ML/d. The operational flow target to end of April at Kywong is 60 ML/d. The lower levels in Murrumbidgee River may lead to lower flows or cease to flow conditions in the Beavers Ck and Old Man Ck systems over coming weeks. A customer notice has been issued on 27 March 2018 to alert the customers and landholders on the flow situation. data/assets/pdf_file/0015/131523/beavers-creek-low-flows- 27-March-2018.pdf Operating Conditions Re-regulation storages are being actively used to capture the excess system flows and to meet the downstream demands. Bundidgerry is currently about 70%, Tombullen at about 95%, Hay Weir at about 100%, Maude Weir at about 50% and Redbank Weir at about 50% of capacity. Page 9 of 32

10 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 reduced as expected. The water levels at Darlington Point gauge is currently about 0.77m and is likely to fall to about 0.5m while meeting the lower demands downstream of Gogeldrie Weir. 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. data/assets/pdf_file/0017/131525/murrumbidgee-low-levelriver-forecasts-ds-gogeldrie-march pdf Flows at Balranald are currently about 270 ML/d and are expected to remain marginally 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. The current flow at Darlot is about 380ML/d and is likely to remain steady over the next week. 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 Blowering Dam: Per latest results (14/03) no cyanobacteria were detected downstream and the storage remains at green alert. Burrinjuck Dam: Per latest results (14/03) no cyanobacteria were detected downstream and the storage remains at green alert, while amber alerts are current for Burrinjuck Dam at Goodhope. Red alerts are current for the Hay Weir Pool including Leonard Street and Hay Weir Boy Sites. Amber alert is current for the Murrumbidgee at Carrathool. Lake Albert in Wagga Wagga is still in a state of Red alert Billabong Creek at Walbundrie (13/03) and Jerilderie (13/03) have green alert Samples from other sites have no alert. o Note: The alert levels apply to non-consumptive or recreational contact. Drinking water safety thresholds are much more stringent o For more information visit: Page 10 of 32

11 Planned Supply Interruptions None. 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 End of Month Storage (GL) Dec-18 Feb-19 Apr-19 Jun-19 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 End of Month Storage (GL) Extreme dry scenario (99%) Dry Scenario (80%) Average scenario (50%) Wet scenario (20%) Actual * Including Snowy releases Burrinjuck Dam Forecast Storage Capacity Updated end-february Extreme dry scenario (99%) Dry Scenario (80%) Average scenario (50%) Wet scenario (20%) Actual * Including Snowy releases Page 11 of 32

12 Lachlan Valley Storage Status Carcoar Dam is at 60% and releases have averaged about 60 ML/d during the last week. Wyangala Dam is at 68% and releases have averaged about 1,000 ML/d during the last week. Predicted Release Patterns The releases have increased to around 65 ML/d from Carcoar Dam due to increased demand. The releases from Wyangala Dam have increased to 1100ML/d and are expected to remain steady for next 2-3 days and reduce later in the week. In the Lower Lachlan, the releases at Brewster have been averaging 310ML/d to meet irrigation demands and to meet the minimum flow target. Demand is predicted to reduce further in the coming weeks. 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 were around 3,000 ML. Lake Cargelligo storage is currently at 50% and it is planned to maintain the storage under 50% 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 2 April 2018, Lake Brewster is at 4% holding about 5 GL totally with about 2.5 GL in the main storage. Latest BGA samples from Lake Brewster show that Willandra Weir and Lake Brewster Regulator C are on amber alert and Lake Brewster outlet channel is on green alert. Lake Cargelligo Outlet and Boatshed are on green alert. As of 12 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 Page 12 of 32

13 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. Initially flows of about 195 ML/d are being directed via the inlet channel from Brewster Weir to raise water levels in the lake s outlet channel and then spill into the outflow wetlands. These flows have now been reduced to around 40ML/d. The next delivery of S&D replenishment flows in the lower Lachlan will be in late autumn 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 13 of 32

14 Macquarie Valley Storage Status Burrendong Dam is currently at 39% and Windamere Dam is at 42% capacity. Predicted Release Patterns Currently releases from Burrendong are around 130 ML/d and are planned to stay just over 100ML/d for rest of the week. Releases from Windamere are currently around 70ML/d and are planned to reduce to 50ML/d later during 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 was required in March to trigger an increment in Available Water Determination. Inflows to Burrendong Dam in March were about 7.5 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 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 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. All 8 guide wire cables have been installed to the anchors on the floor of the dam, in readiness for curtain reinstatement in Autumn Carryover evaporation reduction was applied to remaining carryover balances in HS and GS sub-accounts in Macquarie and Cudgegong Rivers for March quarter of A 3.0% Page 14 of 32

15 reduction was applied to Macquarie River Water Source and a 1.8% reduction was applied on Cudgegong River water source. Carryover balances in EWA incurred the 3.0% 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. Planned Supply Interruptions There are no planned supply interruptions to be undertaken for this week. Page 15 of 32

16 Namoi Valley Storage Status Keepit Dam is at 13%, Split Rock Dam is at 16% and Chaffey Dam is at 70% of active capacity. Predicted Release Patterns The release of water for the Commonwealth Environmental Water Holder from Keepit Dam for stream connectivity to Narrabri continues. Releases to maintain this connectivity are forecast to be about ML/d. Split Rock Dam is releasing around 45 ML/d to deliver about 20 ML/d to Upper Namoi water users. Releases are expected to remain relatively stable for the next week. Chaffey Dam releases have decreased to around 125 ML/d and are forecast to stay around this level for the next week. Demand has been split evenly between Tamworth City of approximately 40 ML/d and industry use of around 40ML/d. Operating Conditions There was no rainfall during the past week with temperatures in the mid 30 s. There is no significant rain forecast for the next week, temperatures are forecast to remain in the low to mid 30 s. Irrigation demand in the lower Namoi has ceased. On completion of environmental (general security) releases, intermittent releases from Keepit will be required to satisfy mining requirements in the upper river sections. 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. 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 above 120GL, the end of system flows will be required to be delivered while the combined storage is above 120GL. Page 16 of 32

17 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 Gigalitres (GL) 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. Flow in the lower reaches of the Namoi and Pian Ck systems has ceased. Cease to flow conditions are now present at multiple locations. If additional environmental deliveries are not undertaken during April, releases for the end of system flow may commence during May. 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 Actual Minimum 99% COE DRY 80% COE Median 50% COE WET 20% COE Page 17 of 32

18 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 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 Gigalitres (GL) 300 Split Rock - forecast storage volume Actual Minimum 99% COE DRY 80% COE Median 50% COE WET 20% COE 100 Chaffey Dam - forecast storage volume actual Minimum 99% COE DRY 80% COE Median 50% COE WET 20% COE Page 18 of 32

19 Gwydir Valley Storage Status Copeton Dam is at 29% of active capacity. Predicted Release Patterns Releases have recommenced Tuesday 3 rd for what is anticipated to be the last Pecan farm delivery. Commonwealth environmental orders for downstream demand throughout April/May are possible. Operating Conditions No rainfall was recorded over the past week and temperatures were mostly in the mid 30s. Forecast temperatures are to remain in the mid 30 s. Summer crop demand has ceased. Following the current release for the Pecan farm there is unlikely to be any significant demand throughout autumn 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. Stream flows have ceased in lower stream sections and the system continues to naturally dry down to a series of waterholes. Planned Supply Interruptions No supply interruptions are expected, though planning is underway to undertake inspections and maintenance activities during May/June. Page 19 of 32

20 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 Gigalitres (GL) 1400 Copeton - forecast storage volume Actual Minimum 99% COE DRY 80% COE Page 20 of 32

21 Border Rivers Storage Status Pindari Dam is at 60%. Glenlyon is at 55%. Predicted Release Patterns Pindari releases remain at minimums of 10 ML/d. Releases are expected to maintain at this level for the next week. Glenlyon releases have increased slightly and are expected to remain relatively steady throughout the week as deliveries continue until the growing season ceases in the upper section, or there is rainfall. Commonwealth environmental deliveries are possible throughout April and May. Operating Conditions No rainfall was recorded over the past week and temperatures were predominantly in the mid 30 s. Temperatures are forecast to remain in the mid 30 s for the next 7 days. 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 environmental deliveries may commence in April/May. End of system flows are gradually declining in line with reducing tributary flows and the lowering of Boggabilla weir. 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. Planned Supply Interruptions Boggabilla weir continues to be lowered gradually to the off season operating level of approximately 40% of the full supply level. Page 21 of 32

22 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 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 Gigalitres (GL) Pindari forecast storage volume Actual Minimum 99% COE DRY 80% COE Median 50% COE WET 20% COE 300 Glenlyon forecast storage volume Actual Minimum 99% COE DRY 80% COE Median 50% COE WET 20% COE Page 22 of 32

23 Barwon Darling River System River Flow Status Flows at Mungindi have averaged 59 ML/d during the past week with end of system flow requirements reducing. Flows are currently around 40 ML/d and will reduce slightly throughout the week. A total flow event volume of approximately 8,000ML has entered the Barwon River from the Moonie River. Flows from the Carole/Gil Gil have averaged 25ML/d and are expected to remain less than 10ML/d over the next 7 days. Flows from the Mehi have averaged less than 5 ML/d for the past week and are expected to be less than 5ML/d for the remainder of the week. Flows from the lower Namoi have averaged around 6ML/d as a result of the Pian Ck replenishment flow, these flows have now ceased. Walgett Weir is currently full and spilling 120ML/d. A total of 20,400ML has passed Walgett during the past 9 weeks. Flows will continue to fall as upstream flows reduce. No inflows from the Macquarie valley are current or are expected in the coming weeks without additional rainfall. Flows from the Moonie river flows have reached Brewarrina weir and peaked at around 1,000ML/d on 28 March. Flows from the Culgoa system reached the Darling on the 24 March. 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 peaked at approximately 3,220ML/d at the Brenda Gauge just inside the NSW Border, with a forecast volume of about 13,500ML. It is expected that total flow from the Culgoa River system will be approximately 12,000ML. Flow connectivity is present from Mungindi to below Louth. Bourke peaked 1,800ML/d on 28 March, with a total flow volume of approximately 16,000 to 17,000ML to pass Bourke over the coming weeks. Page 23 of 32

24 Flows recommenced at Louth on 1 April with a total flow of about 11,000 to 12,000ML expected over the next few 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. Forecasts indicate that there could be up to 1,000ML reach the Darling in early to mid-april. Predicted Flow Patterns Connectivity is likely to extend down to Wilcannia, further advice will be provided as the volumes and losses being experienced become clearer. Operating Conditions A section 324 Temporary Water Restriction order is extended. Temporary restrictions on A, B and C class water access licences in the Barwon-Darling Unregulated River announced on 9 March have been extended to 28 April. From 1 April - the pump restrictions only apply to A, B and C water access licence holders downstream from Boorooma - midway between Walgett and Brewarrina to Lake Wetherell at the top of the Menindee lakes system. From 1 April - The pump restrictions will no longer apply to A, B and C class licence holders upstream from Boorooma to Mungindi. Flows from Queensland from the Moonie and Culgoa Rivers reached the Barwon-Darling in mid- March and are making their way down the system. These flows have replenished town water supplies and provided stock and domestic supply for landholders, the primary objective of the temporary pump restriction announced on 9 March. The pump restriction limits the taking of water to: (a) Town water supply (b) Domestic use (c) Stock watering (d) Irrigation of existing permanent plantings such as vineyards and orchards The temporary pump restrictions have been extended to bring benefit further along the Darling River in coming weeks. Page 24 of 32

25 River section Gauging station 27 March March March March March April April 2018 Classification Classification Classification Classification Classification Classification Classification Mungindi to Boomi River Confluence No access No access No access No access No access No access No access Boomi River Confluence to U/S Mogil Mogil Weir No access No access No access No access No access No access No access Mogil Mogil Weir No access No access No access No access No access No access No access D/S Mogil Mogil to Collarenebri No access No access No access No access No access No access No access Collarenebri to U/S Walgett Weir Class A No access No access No access No access No access No access Walgett Weir No access No access No access No access No access No access No access D/S Walgett to Boorooma No access No access No access No access No access No access No access Boorooma to Brewarrina Class A Class B Class B Class A Class A Class A No access Brewarrina to Culgoa River Junction Class A Class A Class A Class B Class B Class A Class A Culgoa River Junc to Bourke Class A Class B Class B Class B Class A Class A Class A Bourke to Louth No access No access No access No access No access No access No access Louth to Tilpa No access No access No access No access No access No access No access Tilpa to Wilcannia No access No access No access No access No access No access No access Wilcannia to U/S Lake Wetherell No access No access No access No access No access No access No access Note: Although flow triggers may be reached, access is restricted while the restriction order is in place. Page 25 of 32

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27 Bega River Storage Status Brogo is under regulated flow conditions and is currently 100% of active capacity. Predicted Release Patterns Releases are currently at about 20 ML/d via valves and will likely remain relatively stable throughout the week. Operating Conditions Downstream flows continue to recede slowly. There is no current access to uncontrolled flow. Temperatures are forecast to fluctuate between low to high 20 s throughout the week. No significant rainfall is currently forecast for the next week. Recent BGA sampling at Brogo indicates a green alert level is maintained Page 27 of 32

28 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 Storage % capacity Brogo Dam - Forecast Storage Levels 140% 120% 100% 80% 60% 40% 20% 0% Actual Dry 80% COE Median 50% COE Wet 20% COE Minimum 99% COE Page 28 of 32

29 Hunter Valley Storage Status Glenbawn Dam is at 75%, while Glennies Creek Dam is at 71%, and Lostock Dam is 100% (spill reducing) of active capacity. Predicted Release Patterns Releases at Glenbawn Dam have increased today to meet AGL demand and are expected to remain relatively stable throughout the week. Glennies Creek Dam releases remain relatively stable around 20 ML/d as downstream tributaries continue to recede. Lostock Dam began to spill 21 March 2008 with peak natural discharge of just below 10,000 ML/d. Spill has reduced to around 70 ML/d. Discharge will continue to reduce throughout the week. Operating Conditions No further significant rainfall occurred throughout the past week. Supplementary access remains available in the Paterson. Recent BGA sampling at Hunter storages indicates a green alert is maintained at Glenbawn and Glennies Creek dam whilst Lostock remains at amber alert. No further significant rain is forecast for the valleys throughout the next week. Planned Supply Interruptions A trash rack change is required at Glenbawn Dam this week while the planned trach rack change at Glennies creek has been postponed due to inflows. Page 29 of 32

30 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 Storage % capacity 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 Storage % capacity 120% Hunter Dams - Forecast Storage Levels % 100% 80% 60% 40% 20% 0% Actual Dry 80% COE Median 50% COE Wet 20% COE Minimum 99% COE % Lostock Dam - Forecast Storage Level % 80.00% 60.00% 40.00% 20.00% 0.00% Actual Dry 80% COE Median 50% COE Wet 20% COE Drought Page 30 of 32

31 1/02/12 1/07/12 1/12/12 1/05/13 1/10/13 1/03/14 1/08/14 1/01/15 1/06/15 1/11/15 1/04/16 1/09/16 1/02/17 1/07/17 1/12/17 1/05/18 1/10/18 1/03/19 1/08/19 1/01/20 Storage % capacity Toonumbar Dam Storage Status Toonumbar Dam 101% and decreasing. Predicted Release Patterns Passing flows of approximately 80ML/d, uncontrolled spill will continue for the next week. Operating Conditions Recent BGA sampling at Toonumbar has remains at amber alert. 120% 100% Toonumbar Dam- Forecast Storage Level 80% 60% 40% 20% 0% Actual Dry 80% COE Median 50% COE Page 31 of 32

32 WaterNSW (Rural) Dam Levels The following table shows the current status of water supplies at 2 April 2018 River Valley Capacity Current Status Storage Dam, Nearest Town (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 Border Rivers Glenlyon Dam, Stanthorpe Qld % Releases continuing <20% 100% 19.62% 90% Pindari Dam, Inverell % Minimum releases 20% 100% 19.62% 90% Gwydir Valley Copeton Dam, Inverell % Releases recommenced <5% 100% 17.59% 60% Namoi Valley Keepit Dam, Gunnedah % 56 0 Environmental deliveries <20% 100% 7% 80% Split Rock Dam, Manilla % 62 0 Releases for upper Namoi users only <5% 100% 100% N/A Chaffey Dam, Tamworth % 69-1 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 60% 22 0 Irrigation deliveries 10% 100% 0% 95% Murrumbidgee Valley Burrinjuck Dam, Yass % Minimum 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 / environmental 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 0 Spill reducing 90% 100% 100% N/A Coastal Area Toonumbar Dam, Kyogle % 11 0 Dam spilling - reducing 100% 100% 100% N/A Brogo Dam, Bega 9 100% 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 32 of 32