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 5.3 Ovens system
Table 5.3.1 Potential environmental watering actions and objectives for the Ovens system
    Potential environmental watering action
 Autumn fresh (one fresh of greater than 430 ML/day for three days in reaches 1 and 4, and greater than 130-260 ML/day in reach 5 during March to April)
• Provide flow cues to stimulate the movement of native fish
• Maintain connectivity between pools for fish movement
• Mix pools to improve the water quality
• Provide small variations in river levels and velocity, to flush sediment from hard substrates and maintain waterbug habitat
• Scour biofilm from the river bed
      Summer/autumn low-flow variability (greater than 80 ML/day for one to two days during February to March in reaches 1, 2 and 3)
• Maintain connectivity between pools for fish movement and water quality
• Provide small variations in river levels to move sediment and maintain waterbug habitat
              Mullinmur Wetland (top- up during November to February)
Scenario planning
Table 5.3.2 outlines the potential environmental watering and expected water use under a range of planning scenarios.
The weather and inflows into storages have a large effect on how water for the environment is likely to be used in the Ovens system. Under dry and average conditions, water for the environment may be used to provide low flow variability and avoid cease-to-flow events in the river reaches immediately below the storages. Under average conditions, water for the environment may also be used in conjunction with operational water bulk transfers from Lake Buffalo to deliver larger freshes and achieve environmental outcomes over a much greater length of river. Planned watering actions under a drought scenario remain the same as those under a dry scenario, however access to entitlements may be restricted if rights to environmental water are qualified.
Watering Mullinmur Wetland is a high priority under dry
and average scenarios. No potential watering actions have been identified for the Ovens system under a wet scenario because the environmental flow requirements are likely to be achieved naturally through storage spills and unregulated tributary inflows.
• Maintain the water level to support the growth and recruitment of aquatic vegetation
• Maintain habitat for freshwater catfish
         244 | Victorian Environmental Water Holder | Seasonal Watering Plan 2020–21
Functional watering objectives
Environmental objectives
                 











































































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