Page 253 - VEWH Seasonal Watering Plan 2020-21
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Table 5.4.1 Potential environmental watering actions and objectives for the Goulburn River
5.4 Goulburn system
 Potential environmental watering action
  Functional watering objectives
  Environmental objectives
  Year-round low flow (500- 830 ML/day in reach 4 and 540-940 ML/day in reach 5)
    • Provide slow, shallow habitat required for the recruitment of larvae/juvenile fish and habitat for adult small-bodied fish
• Provide deep-water habitat for large-bodied fish
• Submerge snags to provide habitat for fish and waterbugs and a substrate for biofilms to grow
• Maintain habitat for aquatic vegetation and water the root zone of low- bank vegetation
• Vary flow within a specified range to encourage planktonic production (for food), disrupt biofilms and maintain water quality
                 Winter/spring fresh (one
to two freshes of more than 6,600 ML for 14 days during July to October in reaches 4 and 5)
 • Improve macroinvertebrate habitat by improving water quality and by increasing the wetted perimeter
• Provide carbon (e.g. leaf litter) to the channel
• Wet bench habitats to encourage plant germination
• Remove terrestrial vegetation and trigger the recruitment of native bank vegetation
           Provide slower recession to unregulated flows or releases from Goulburn Weir (3,000 ML/day and below in summer/autumn and from 6,000 ML/day
in winter/spring) in reaches 4 and 5
  • Minimise the risk of bank erosion associated with rapid drying
• Minimise the risk of hypoxic blackwater after natural events
           Spring/autumn/winter low flow (400 ML/day during July to September and April to June in reach 1)
 • Wet and maintain riffles to provide habitat for biofilms and waterbugs
• Scour fine sediment from the gravel bed and riffle substrate
• Maintain the wetted perimeter of the channel and habitat for aquatic vegetation
• Maintain existing beds of in-channel vegetation
• Maintain habitat for small-bodied native fish
              Winter fresh (up to 15,000 ML/day with more than 14 days above 6,600 ML/day in June/July 2021, reaches 4 and 5)
    • Improve macroinvertebrate habitat by improving water quality and by increasing the wetted perimeter
• Provide carbon (e.g. leaf litter) to the channel
• Wet bench habitats to encourage plant germination
• Remove terrestrial vegetation and trigger the recruitment of native bank vegetation
               Flows should not exceed 1,000 ML/day for five to six weeks after a spring fresh (in late spring/summer) in reaches 4 and 5
 • Allow newly grown littoral emergent and semi-aquatic plants to become established and persist
• Provide habitat for small-bodied fish and macroinvertebrates
               One spring/summer fresh (greater than 6,600 ML for one day between November and December in reaches 4 and 5)
  • Provide a cue for golden and silver perch to spawn
         Victorian Environmental Water Holder | Seasonal Watering Plan 2020–21 | 251
 




























































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