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Table 5.7.1 Potential environmental watering actions and objectives for the Loddon River system
5.7 Loddon system
 Potential environmental watering action
  Functional watering objectives
    Environmental objectives
   Loddon River (targeting reach 4)
    Summer/autumn fresh (one to three freshes of 50–100 ML/day for three to four days during December to May)1
    • Flush fine sediment from hard surfaces
• Increase the water level, to promote the growth of fringing emergent macrophytes
• Increase connectivity to promote the local movement of fish and platypus including juvenile dispersal in autumn
• Freshen water quality and re-oxygenate pools
            Winter/spring high flow (one high flow of
450–750 ML/day for six
to 10 days during August to November)2
     • Scour accumulated sediment from pools and scour biofilms
• Flush accumulated organic matter from the bank and benches, to increase productivity and reduce the risk of a hypoxic blackwater event in summer
• Increase the wetted area, to promote the recruitment and growth of streamside and emergent vegetation
• Stimulate native fish movement and breeding
            Summer/autumn low flow (25–50 ML/day during December to May)3
  • Maintain an adequate depth in pools for aquatic plants and to provide habitat for waterbugs, fish and rakali (water rats)
• Provide continuous flow through the reach, to maintain water quality
• Maintain connecting flows to support in-stream and fringing non-woody vegetation
               Winter/spring low flow (504–100 ML/day during June to November)
    • Increase the water depth for fish, platypus and rakali (water rats) dispersal and to provide foraging habitat
• Prevent silt and fine sediment settling on submerged wood and other hard surfaces
• Water the native fringing bank vegetation and prevent the growth of exotic terrestrial plants in the river channel
                   Autumn high flow
(one high flow of 400 ML/ day for six to 10 days during March to May)
  • Trigger and facilitate the upstream movement of golden perch, silver perch and Murray cod older than one year
• Facilitate platypus dispersal
         Victorian Environmental Water Holder | Seasonal Watering Plan 2020–21 | 287

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