Waterways -rivers and inland and wetlands
The waterways of East Gippsland are important features of the landscape, providing water for agriculture and domestic use, having high social and cultural values and for being largely in good condition, with approximately 82% assessed as being of ‘Excellent’ or ‘Good’ condition in Victoria (EGCMA, 2014).
Asset vulnerability
In East Gippsland, rivers were not considered as being highly vulnerable to climate change, because of their generally good condition (Spatial Vision & Natural Decisions, 2014). The rivers with the highest potential vulnerability in the region are the upper reaches of the (unregulated) waterways such as Suggan Buggan River, Rocky River, Little River East Branch, Butchers Creek, Bonang River, Boggy Creek and Bendoc River.
Unlike waterways in other regions, the vulnerability of these rivers is due to their inherent sensitivity rather than their adaptive capacity. The vulnerable waterways in East Gippsland are all located in the upper catchment and are unregulated and, due to their location in the catchment, are sensitive to changes in rainfall in order to maintain their flow regimes.
Regarding inland wetlands, shallow freshwater marshes and freshwater meadows on freehold and public land within the Gippsland Lakes and Hinterlands, the East Coast Landscape Areas and the Alpine Peatlands were found to be the most vulnerable as a result of their low adaptive capacity (lack of connectivity and remnant vegetation) and their sensitivity to changes in rainfall and increases in temperature (Spatial Vision & Natural Decisions, 2014).
The impact of climate change on existing threats to natural assets in East Gippsland was assessed through a simple framework. For rivers and inland wetlands, climate change was assessed as having the highest impact on threats from invasive plants, degraded riparian zones and altered flow regimes. For alpine wetlands there is also likely to be a high impact on threats from invasive animals (through increased populations and range of invasive species) and fire regime (from a predicted increased frequency of fire). A focus on managing these threats will contribute to improving the adaptive capacity of waterways in the region to adapt to a changing climate.
Potential adaptation options
Potential adaptation options for rivers and inland wetlands in response to key climate change variables are set out in Table 1 below and have formed the basis of analysis for development of this Plan:
Table 1. Potential adaptation options for rivers and inland wetlands in East Gippsland.
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Climate Change Variables |
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Reduced and more variable rainfall |
Increased temperature and extreme heat |
Increased intensity and frequency of rainfall events (including flooding) |
Increased frequency of fire |
Storm surge and sea level rise |
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Rivers |
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Increase extent of riparian vegetation and improve connectivity of corridors to provide shading of waterways
Provision of environmental flows
Protection of summer base flows (regulation of timing / magnitude of extraction) |
Protection of refuge areas for fish and aquatic fauna in conjunction with pest species programs
Establishment of riparian vegetation; in stream habitat restoration
Control competing aquatic species (plant and animal) |
Maintenance of ground cover in strategic areas
Geomorphic recovery through works (vegetation and structural)
Management of flashy surface water inflows in urban / agricultural environments through swale drains and constructed wetlands |
Focus fuel reduction burning to protect vulnerable areas.
Increase effort in recovery programs to assist with rehabilitation of burnt habitats. |
Allow for migration of habitats as salinity level increases
Consider artificial barriers to maintain freshwater / brackish habitats |
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Wetlands |
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Removing existing artificial barriers or lowering ‘commence to fill’ levels
Preventing disturbance to the peat structure of alpine wetlands (e.g. through fire, physical damage etc), which can accelerate drying |
Weed and pest control to improve condition and adaptive capacity
Improve connectivity between wetland habitats
Restore buffer vegetation around wetlands
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Management of flashy surface water inflows in urban / agricultural environments through swale drains and constructed wetlands |
As for rivers |
As for rivers |
