Page 160 - VEWH Seasonal Watering Plan 2020-21
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 4.3 Wimmera system
Table 4.3.1 Potential environmental watering actions and objectives for the Wimmera system
 Potential environmental watering action
  Functional watering objectives
  Environmental objectives
  Wimmera River (reaches 2 & 3)
  Winter/spring low flow (100 ML/day during June to November)
 • Provide fish passage to allow fish to move through the reach
• Maintain soil moisture for streamside vegetation and a near-permanent wetted stream channel for aquatic vegetation
• Prevent the growth of terrestrial plants in the stream bed
          Wimmera River (reach 4)
    Summer/autumn low flow (15 ML/day or natural during December to May)
  • Maintain edge habitats in deeper pools and in-stream habitat to support native fish populations and waterbugs
• Maintain soil moisture for streamside vegetation and near-permanent wetted stream channel for aquatic vegetation and to prevent the growth of terrestrial plants in the stream bed
         Winter/spring low flow (30 ML/day during June to November)
 • Maintain access to habitat for native fish, waterbugs and in-stream vegetation
           Summer/autumn fresh (one to five freshes of 70 ML/day for one to four days during December to May)
  • Flush pools to prevent decline of water quality and maintain habitat for fish and waterbugs
• Provide fish passage to allow fish to move through the reach
                Small winter/spring fresh (one to three freshes of 70 ML/day for one to five days during June to November)
    • Increase water depth to provide stimulus for fish movement
• Provide flow variability to maintain water quality and diversity of fish habitats
          Large winter/spring fresh (one to three freshes of 200 ML/day for one to three days during June to November)
    • Wet lower benches, entrain organic debris and increase habitat availability for waterbugs and fish
            MacKenzie River (reach 2)
    Summer/autumn low flow (two ML/day or natural during December to May)
  • Maintain edge habitats and deeper pools and runs for waterbugs, platypus and fish
• Maintain soil moisture for streamside vegetation and a near-permanent wetted stream channel for aquatic vegetation
• Prevent the growth of terrestrial plants in the stream bed
           Winter/spring low flow
(27 ML/day or natural during June to November)
 • Facilitate the annual dispersal of juvenile platypus into the Wimmera River
          158 | Victorian Environmental Water Holder | Seasonal Watering Plan 2020–21
 

































































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