Page 36 - VEWH Seasonal Watering Plan 2020-21
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 1.5 How to read the seasonal watering plan
• recent conditions, which describes the factors that will be considered when planning environmental flows in the coming year (such as the past watering regime, climate and rainfall, water availability, system operations, monitoring results and environmental observations)
• scope of environmental watering, which is a table of potential environmental watering actions in 2019–20, their functional watering objectives (that is, the intended physical or biological effect of the watering action) and the longer- term environmental objective they support. Each environmental objective relies on one or more potential environmental watering actions and their associated physical or biological functions. Figure 1.5.2 is an example of this table.
Figure 1.5.2. Example potential environmental watering actions and objectives tables
   Potential environmental watering actions describe the timing, magnitude, duration and frequency of environmental flows to rivers or the timing of releases to wetlands. Subsection 1.3.3 explains how watering actions are prioritised. The seasonal watering statements issued by the VEWH authorise waterway managers to undertake environmental watering actions described in this table. Subsection 1.2.2 explains how seasonal watering statements fit into the environmental watering planning framework.
Environmental objectives are those listed in the environmental objectives table for each system (as the Figure 1.5.1 example above shows). Each environmental objective will be supported by
one or more watering actions and functional watering objectives.
   Potential environmental watering action
  Functional watering objectives
    Environmental objectives
 Macalister River reaches 1 and 2
        Winter to summer low flow (up to 90 ML/day in June to December)
   • Provide hydraulic habitat for fish by increasing water depth in pools
• Provide fish passage for local movement through minimum depth over riffles
• Provide permanent wetted habitat for water bugs through minimum water depth in pools
• Provide connectivity throughout the river for local movement of platypus and water rats, as well as protection from predation, access to food sources and maintain refuge habitats
• Provide flows with low water velocity and appropriate depth and to improve water clarity and enable establishment of in- stream vegetation
• Provide sustained wetting of low-level benches (increasing water depth) to limit terrestrial vegetation encroachment
            Summer-autumn low flow (35-90 ML/day in January-May)
 • Maintain water depth in pools and hydraulic habitat for native fish.
• Maintain permanent wetted habitat in pools and riffles for waterbugs
• Maintain shallow, slow-flowing habitat to enable establishment of in-stream vegetation
• Maintain a minimum depth in pools to allow for turnover of water and slow water quality degradation
• Expose and dry lower channel features for re-oxygenation
                These example icons demonstrate which potential watering actions may be modified to increase benefits to Traditional Owner values or recreational opportunities, provided environmental outcomes are not compromised.
The ability of the VEWH and its partners to modify flows to deliver these benefits will depend on the weather, climate considerations, the available water and the way the system is being operated to deliver water for other purposes.
A functional watering objective is the physical or biological effect that a potential watering action aims to achieve. Each potential watering action will have one or more functional watering objectives.
34 | Victorian Environmental Water Holder | Seasonal Watering Plan 2020–21

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