Environmental watering – CEWH 2016 Improved native fish breeding success: Golden perch, Silver perch, Murray hardyhead, Bony bream, Murray cod and rainbowfish and gudgeon species. Native bird breeding boom, including first of internationally protected Eastern great egrets since 2011, following environmental water to the Yanga National Park in early 2015. Significant increases in waterbird species diversity and total abundance at sites that received environmental water in Gwydir river system Revegetation stabilising banks in Goulburn River system Improved dissolved oxygen and black water mitigation

Just add water 2750GL and 3200GL targets derived from models aiming to deliver flow rates in river sections, not environmental outcomes in key indicator or high value sites. Assumption that flow targets will deliver overbank flooding to achieve desired environmental outcomes ‘naturally’. Constraints: Regulatory, physical, environmental, socio-economic Obtaining flood easements Upgrading roads, bridge and other infrastructure Flood mitigation works – ie, levees Increasing dam outlet capacities $200 m for above measures Constraints restrict environmental watering to in-stream, riverbank and lower floodplain. Environmental offset works and measures to improve extent of environmental watering and its success

450GL upwater and relaxed constraints “Hydrologic modelling of the relaxation of operational constraints in the southern connected system: Methods and results”. October 2012, MDBA. Region Location Existing constraint ML/d Relaxed constraint in model ML/d Murray Hume to Yarrawonga 25,000 40,000 Downstream of Yarrawonga 22,000 Lower Darling Weir 32/increase Menindee outlet capacity 9300 18,000 Darling Anabranch Water flows into anabranch over 9300 ML/d (no regulator) Regulator added and closed >9300 ML/d when water supplied for enviro in Murray Murrumbidgee Gundagai 30,000 50,000 Balranald 9000 13,000 Goulburn Seymour 12,000 15,000 McCoy’s Bridge 20,000

Environmental effects Flows increased from 60,000 ML/d to 80,000 ML/d at SA border 40% of wetlands inundated vs 75% between Darling River and Lock 1 (additional 60,000 ha of Chowilla/Riverland, watering to mid-level floodplain) * 27,500 ML/d Swan Hill late October 2016; **94,600 ML/d at SA border last week November 2016 Frequency Pre-1788 Pre-Basin Plan 2800GL 3200=RC 3 years 10 years 8 years 5.5 years High-flow targets: 450GL, relaxed constraints – possible improved bird breeding 35,000 ML/d for 30 days at Barmah-Millewa forest 40,000 ML/d for 60 days at Gunbower-Koondrook-Perricoota 20,000 ML/d for 150 days at Gunbower-Koondrook-Perricoota* 70,000 ML/d for 42 days at Hattah Lakes 80,000 ML/d for 30 days at Riverland-Chowilla floodplain**

Lower lakes, Coorong and Murray Mouth Subtle environmental outcomes but environmental indicators unlikely to be particularly sensitive compared with upstream sites that rely on high flows to inundate mid-high floodplain levels. (Note: Keystone species Ruppia tuberosa seagrass salinity tolerance range: up to 80-90g/l Indicator BP Target Pre-1788 2009 baseline 2800 GL BP 3200 GL BP - RC Average salinity in Coorong southern lagoon Less than 60g/l 24 62 44 41 Max. days salinity over 130 g/l in southern Coorong 323 % years salinity <100 g/l in southern Coorong >95% 100% 82% 96% Average salinity in Coorong northern lagoon Less than 20g/l 12 29 21 20 Max. days salinity over 50 g/l in northern Coorong 604 75 Lower Lakes level (mAHD) 0.4m AHD -0.4m (Jan 2009) 0.4m (Jan 2003) 0.2m (Jan 2009) 0.7m (Jan 2003) Murray mouth bed level -1m -2.5m 2009 -2.5m 2003 0.0m (Jan 2009) -0.5m (Jan 2003) -0.5m (Jan 2009 -1.5m (Jan 2003) -0.5m (Jan 2009) -1.0m (Jan 2003)

MDBA conclusions “Hydrologic modelling of the relaxation of operational constraints in the southern connected system: Methods and results”. October 2012, MDBA. If constraints can be overcome, likely to be increased ecological benefits for floodplains, particularly if combined with great water recovery. (pxiv) Work done previously by MDBA shows increasing impacts on communities of water recovery greater than 2750GL/y, and this was an important consideration in MDBA’s proposed ESLT. (pxiv) Overcoming constraints: “This would require a commitment and significant investment from both State and Federal governments and would be subject to further assessments, cost/benefit analysis (including assessments of any third party impacts) and extensive community consultation.” (piv) - Federal water special account has $200 million budget for addressing constraints