Page 122 - VEWH Seasonal Watering Plan 2020-21
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               3.6 Moorabool system
Scenario planning
Table 3.6.2 outlines the potential environmental watering and expected water use under a range of planning scenarios.
The highest environmental flow priority under all scenarios in the Moorabool River in 2020–21 will be to provide continuous low flows during summer and autumn to maintain habitat for fish, waterbugs, platypus and aquatic vegetation, to allow fish and platypus to disperse and to protect water quality. Maintaining continuous low flows in winter and spring is also a high priority when these flows are not met naturally. Spring freshes are a high priority under dry, average and wet scenarios to cue the upstream migration of juvenile galaxias, tupong, short-finned eel and Australian grayling.
Summer and autumn freshes are important under drought and dry scenarios, to help mitigate against extreme water quality conditions that may threaten fish and other aquatic animals in refuge pools. Autumn and winter freshes may be delivered under average and wet conditions to cue tupong and Australian grayling to migrate and spawn. Freshes at any time of year will help transport nutrients through the system and scour biofilms and algae from the streambed and other hard surfaces.
Although environmental watering in the Moorabool River primarily targets outcomes in reaches 3a and 3b, deliveries will be planned where possible to also provide benefits in reach 4.
Critical carryover of 1,000 ML has been identified to allow delivery of trigger-based freshes in 2021–22, if there is low allocation.
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