Table 2. Summary of 2015–16 watering actions targeting stream metabolism and generic ecosystem functioning in Selected Areas. Selected Area Dates Flow component type Commonwealth environmental water volume delivered (GL) Monitored site(s) Expected ecological outcome Observed ecological outcomes Influences Goulburn River (lower river channel) 01/07/15 – 08/07/15 Fresh 10.661 McCoy’s Bridge Support ecosystem function to commencement of data collection in August 2015. Goulburn River (lower river channel) 09/07/15 – 02/10/15 Base 10.549 McCoy’s Bridge Support ecosystem function Small increases in rates of primary production (GPP) and ecosystem respiration (ER). Increased rates due to increasing water temperatures and longer days coupled with possible enhanced nutrient and organic carbon availability. Goulburn River (lower river channel) 03/10/15 – 29/10/15 99.139 Bridge Support ecosystem function Rates depressed by large dilution effect but increasing on the receding limb of the hydrograph. Eventual rate increased due to increasing water temperatures and longer days coupled with possible enhanced nutrient and organic carbon availability. Goulburn River (lower river channel) 30/10/15 – 12/03/16 Base 0.915 McCoy’s Bridge Support ecosystem function Rates generally increased over this period. Unable to distinguish effects of watering action from seasonal changes. Goulburn River (lower river channel) 15/03/16 – 05/04/16 Base 26.961 McCoy’s Bridge Support ecosystem function Rates depressed by significant dilution effect. Increases in ER but not GPP on falling hydrograph. Lack of response in GPP on the falling hydrograph likely due to cooler water temperatures and shorter days. Goulburn River (lower river channel) 06/04/16 – 30/06/16 Base 33.356 McCoy’s Bridge Support ecosystem function Any effects of this watering action were after completion of 2015–16 monitoring. Gwydir 10/04/16 – 30/05/16 Base 2.600 Pallamallawa Support fundamental ecosystem function processes No data available.
Table 3. Summary of 2015–16 watering actions targeting stream metabolism and generic ecosystem functioning at unmonitored sites. Valley name (Water Action Reference) Commonwealth environmental water delivered (ML) Flow component type Location Expected ecological outcomes Lachlan (10039) 03/08/15 – 15/10/15 24 059 Fresh Lachlan – Great Cumbung Swamp Contribute to ecosystem functions. Moonie (111-27) 28/08/15 – 02/09/15 201 QLD Moonie – Lower Moonie River and fringing wetlands Contribute to natural flow events to support key ecosystem functions and aquatic habitats. Border Rivers (111-26) 26/07/15 – 07/08/15 409 Fresh QLD Border Rivers – Dumaresq–Macintyre River and fringing wetlands Contribute to nutrient and sediment cycling (from inundation of channel areas, some anabranch channel and near-stream wetlands).Other fish and hydrological objectives. Border Rivers (111-26) 26/08/15 235 Fresh QLD Border Rivers – Dumaresq–Macintyre River and fringing wetlands Nutrient and sediment cycling (from inundation of upper channel areas, some anabranch channel and near-stream wetlands). fish and hydrological objectives. Border Rivers (111-26) 07/11/15 244 Fresh QLD Border Rivers – Dumaresq–Macintyre and fringing wetlands Nutrient and sediment cycling (from inundation of upper channel areas, some anabranch channel and near-stream wetlands). Other fish and hydrological objectives. Border Rivers (111-26) 02/02/16 137 QLD Border Rivers – Dumaresq–Macintyre River and fringing wetlands Nutrient and sediment cycling (from inundation of upper channel areas, some anabranch channel and near-stream wetlands). Other fish and hydrological objectives. Murrumbidgee (10035-09) 17/11/15 – 11/01/16 10 000 Wetland inundation (via the most direct path to Tarwillie Swamp to minimise incidental inundation of vegetation that has achieved its required flooding regime in recent years) Murrumbidgee – Yanga National Park waterbird support Support ecosystem functions.
(10004-02) 25/04/16 20 Release with a bulk release if one occurs, otherwise when advised by Ovens River with benefit to Buffalo River en route from Lake Buffalo Improve primary production through the disruption of biofilms. Lower Murray 12/10/15 – 23/10/15 5348 Wetland Hattah Promote exchange and cycling of nutrients and carbon between the river and the lakes.
Annex A. Other watering actions associated with water quality Table A1 lists those watering actions that explicitly targeted water quality outcomes (as distinct from stream metabolism) or for which water quality was a target of monitoring. The three Barwon–Darling watering actions listed in Table 2 also had the water quality objective ‘Water quality improvement including salinity and potential for algal blooms’. Similarly, three of the six Goulburn River watering actions in Table 2 also had the water quality objective ‘Maintain water quality’. A1. Watering actions explicitly targeting water quality outcomes (as distinct from stream metabolism) or for which water quality was the target of monitoring. Location (CEWO Action Reference) Dates Flow component type Commonwealth environmental water volume delivered (ML) Expected ecological outcome Monitored site(s) Observed ecological outcomes Influences Broken Creek (lower) – Reach 3 (10041-01 2015–16) 18/08/15 – 30/11/15 Base flow 7183 Manage excessive azolla growth. Rices Weir Broken Creek (lower) 3 (10041-01 2015–16) 01/10/15 – 16/05/16 Base flow 23 542 Maintain water quality, including dissolved oxygen (DO) levels >5 mg/L. Rices Weir Low oxygen in early March 2016 (O2 < 2mg/L) High temperature (30 °C), decomposition and respiration of blue-green algae Broken Creek (lower) 3 (10041-01 2015–16) 28/09/15 – 30/11/15 Fresh 6188 Remove azolla blooms. Rices Weir Campaspe – Reach 4 (10003-02 2015–16) 26/08/15 – 05/09/15 Fresh 1700 and mix pools for improved water quality. Not monitored Not monitored Campaspe – 4 (10003-02 2015–16) 27/10/15 – 04/11/15 Fresh flow 1559 Flush and mix pools for improved water quality. Mitigate threat of a summer toxic blackwater event. Not monitored Not monitored Edward–Wakool (10038-05) 17/09/15 – 22/11/15 Base flow; fresh 2000 Maintain/improve water quality (especially dissolved oxygen, pH and salinity). Tuppal Creek
Gwydir (10043-03, 10043-05) 2016 Base flow 409 Mitigate declining water quality. Carole No water quality issues reported Gwydir (10043-04, 10043-05) April–May 2016 Base flow 2191 Maintain water quality. Mehi River No quality issues reported Gwydir (10043-05) 2016 Base flow 3400 Mitigate declining water quality. Gwydir No water quality issues reported Lachlan (10033-01, variation) 11/11/15 – 15/12/15 Fresh and/or regulated flow 9379 Improve quality. Lower Lachlan River Channel Loddon – Reach 4 (10001-02 2015–16) 24/08/15 – 07/09/15 Fresh 1477 Maintain hydrological connectivity and water quality. Lower Murray – SA (10031-03, 10047-01) 01/07/15 – 30/11/15 Base flow 556 000 Support the managed transport and export of salt and nutrients from the Murray system. Australian River Murray and Coorong Lower Murray – SA (10031-03, 10047-01) 01/12/15 – 01/07/16 Base flow 242 000 - Reduce peak salinity in Coorong. South Australian River Murray and Coorong Salinity in north lagoon decreased Lower Murray – NSW, Vic and SA Murray – weir pool manipulation, Lock 15 raising and lowering (10031-06, 10031-09) 01/07/15 – 30/06/16 Fresh 5249 Support the managed transport and export of salt and nutrients from the River Murray system. Lower Murray – NSW, Vic and SA Murray – weir pool manipulation, Lock 7 raising and lowering (10031-06, 10031-09) 01/08/15 – 30/05/16 Fresh 2739 Support the managed transport and export of salt and nutrients from the Murray system.