Page 278 - VEWH Seasonal Watering Plan 2020-21
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 5.6 Campaspe system
Table 5.6.1 Potential environmental watering actions and objectives for the Campaspe River
 Potential environmental watering action
  Functional watering objectives
    Environmental objectives
    Summer/autumn low flow (10–50 ML/day during December to May)
  • Maintain slackwater habitats for zooplankton and nursery habitats for native fish
• Maintain the water quality and depth in deep pools in summer for native fish and platypus
• Allow platypus to safely move between pools while foraging and ensure adequate food for lactating females
            Year-round fresh (five to 200 ML/day for one to 14 days, as needed)
 • A fresh may be required when dissolved oxygen levels are below 5 mg/L, air temperatures are above 28°, there are high water temperatures and/ or low river flows to improve water quality along the river pools and de- stratify pools in reach 4, ensuring adequate oxygen to support aquatic animals (such as native fish and platypus)
           Reduced1 winter/spring low flow (20–40 ML/day during June to November)
• Increase longitudinal connectivity to allow native fish to access new habitats
• Facilitate the long-distance movement of male platypus, especially in the August/October breeding season. Provide foraging opportunities across a wide range of habitats for females to develop fat reserves before breeding.
• Maintain water quality by preventing pools stratifying
           Winter/spring freshes (two freshes of 1,100–1,600 ML/ day for two to five days during June to November)
• Flush accumulated leaf litter from banks and low benches to reduce the risk of blackwater events during high river flow in summer
• Maintain soil moisture for established river red gum and woody shrubs (such as bottlebrush and tea tree)
• Maintain connectivity to allow native fish movement and access new habitats
• Encourage females platypus to select a nesting burrow higher up the bank to reduce risk of high flow later in the year flooding the burrow when juveniles are present
                  Winter/spring low flow (40–200 ML/day during June to November)
    • Increase longitudinal connectivity to allow native fish to access new habitats
• Facilitate long distance movement by male platypus especially in the August/October breeding season
• Provide foraging opportunities across a wide range of habitats for female platypus to develop fat reserves before breeding
• Maintain water quality by preventing pools stratifying
• Reduce terrestrial plants colonising the lower sections of the riverbank and low benches in the channel
• Maintain soil moisture in the riverbank to water established river red gums and woody shrubs
• Help establish littoral vegetation
                 Summer/autumn freshes (one to three freshes 100–200 ML/day for two to three days during December to May)
  • Increase longitudinal connectivity to allow native fish to access new habitats
• Wet submerged wood and flush fine silt and old biofilms to promote new biofilm growth and increase waterbug productivity for native fish and platypus
• Facilitate the downstream dispersal of juvenile platypus in April/May to colonise other habitat areas
          1 Winter low flow of 20-40 ML/day is below the environmental flow recommendation of a minimum of 50 ML/day due to low water availability in the drought- dry scenario
    276 | Victorian Environmental Water Holder | Seasonal Watering Plan 2020–21
 
































































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