Page 66 - VEWH Seasonal Watering Plan 2020-21
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 2.3 Thomson system
Table 2.3.2 Potential environmental watering for the Thomson River under a range of planning scenarios
 Planning scenario
   Drought
   Dry
   Average
   Wet
   Expected river conditions
 • Limited natural flow
• Large volume of consumptive water released from storage
 • Natural flow from Aberfeldy River and other tributaries contributes to low flow and freshes
• Moderate volume of consumptive water released from storage
 • Natural flow from Aberfeldy River and other tributaries contributes to low flow, freshes and high flows
• Small volume of consumptive water released from storage
 • Natural flow from Aberfeldy River and other tributaries contributes to low flow, freshes and sustained high flows
• Minimal volume
of consumptive water released from storage
 Expected availability of water for the environment
   • 29,000 ML
   • 32,000 ML
   • 35,000 ML
   • 38,000 ML
   Potential environmental watering – tier 1a (high priorities)
 • Two autumn freshes
• One spring fresh
• Two summer/autumn freshes
• Winter/spring low flow
   • Two autumn freshes
• Two spring freshes
• Two summer/autumn freshes
• Winter/spring low flow
  Potential environmental watering – tier 1b (high priorities with shortfall)
 • N/A
 Potential environmental watering – tier 2 (additional priorities)
  • Summer/autumn low flow
 • N/A
 Possible volume of environmental water required to achieve objectives1
  • 27,000 ML (tier 1a)
• 16,700 ML (tier 2)
   • 31,200 ML (tier 1a)
• 16,700 ML (tier 2)
   • 34,500 ML (tier 1a)
• 6,300 ML (tier 2)
   • 37,300 ML (tier 1a)
  Priority carryover requirements
 • 5,500 ML2
 Heyfield wetlands
           Potential environmental watering – tier 1a (high priorities)
 • Fill (in August)
• Top-ups to maintain water level as required (during October to November)
• Partial drying (during December to February)
 Possible volume of environmental water required to achieve objectives
   • 15–25 ML (tier 1a)
  • 10–17 ML (tier 1a)
   • 7–12 ML (tier 1a)
   1 Environmental water requirements for tier 2 actions are additional to tier 1 requirements.
2 Priority carryover volumes have been incorporated into tier 1a demands.
   64 | Victorian Environmental Water Holder | Seasonal Watering Plan 2020–21









































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