Page 56 - VEWH Seasonal Watering Plan 2020-21
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 2.2. Latrobe system
Table 2.2.3 Potential environmental watering actions and objectives for the lower Latrobe wetlands
     Potential environmental watering action
Sale Common
Partial fill (during July to December, with top-ups as required to maintain water height above 0.3m AHD [Australian Height Datum])
Fill (during August to November and maintain at full level for at least two months)1
Top-up (anytime, following bird breeding event if required)
Dowd Morass
Partial fill (during April to December, with top-ups over summer to maintain surface coverage)2
Fill (during August to November)
Trigger-based fill or
partial fill to control salinity (any time)3
Top-up (anytime, following bird breeding event if required)
Functional watering objectives
Maintain a water level at 50 percent or greater (0.3m AHD) to:
• encourage the growth and flowering of semi-aquatic plants
• provide appropriate wetland habitat for frogs and turtles
• provide conditions that support waterbug communities and food resources for waterbirds
• wet key habitats within the wetland for sufficient duration to discourage invasive plants, particularly the excessive spread of giant rush
• Wet the outer boundaries of the wetland to support the growth and flowering of streamside and fringing wetland plants, increasing foraging opportunities for waterbirds
• Encourage bird breeding by providing nesting habitat to wet reed beds and provide deep water next to reedbeds
• Provide connectivity between the river and wetlands and increase habitat and feeding opportunities for frogs and turtles
• Prolong wetting of reed beds to maintain habitat and food resources for nesting waterbirds and protect chicks from predators
• Provide seasonal variation in water depth throughout the wetland to support the growth and flowering of semi-aquatic plants
• Wet vegetation and soils at middle elevations within the wetland to increase the abundance of waterbugs and other food resources for frogs, turtles and waterbirds
• Provide connectivity between the river and wetlands and between wetlands, increasing available habitat for frogs and turtles
• Support bird breeding (when delivered in spring/early summer following earlier fill) by maintaining wetted habitat around reed beds
• Wet reed beds and deep water next to reedbeds to provide waterbird nesting habitat and to stimulate bird breeding
• Wet high-elevation banks and streamside zone to support vegetation growth, creating nesting habitat for waterbirds
• Wet vegetation and soils at higher elevations to stimulate ecosystem productivity and increase the abundance of waterbugs and other food resources for frogs, turtles and waterbirds
• Provide connectivity between the river and wetlands and between wetlands, increasing available habitat for frogs and turtles
• Dilute salt concentrations within the wetland that may be caused by king tides from Lake Wellington (likely occurring between March to May) or other sources
• This watering action is likely to be triggered4 if electrical conductivity is rising and reaches 7,000 μS/cm
• Prolong wetting of reed beds to maintain habitat for waterbirds and protect chicks from predators, following an observed breeding event
Environmental objectives
                                                          54 | Victorian Environmental Water Holder | Seasonal Watering Plan 2020–21
 






























































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