Victorian Waterways Management Strategy: Submission from the Concerned Waterways Alliance

, By Yarra

Waterways, wetland and estuarine health in Victoria will come under an existential threat in the life of the next Victorian Waterway Management Strategy (VWMS).  In that time climate change is going to bite and we will see many of our streams start to show the impacts of landscape and hydrologic changes.  We are likely to witness many permanent streams become more seasonal or indeed ephemeral.  There will be massive challenges from those with a utilitarian bent to prevent the diminished water resource being plundered by those who see river flows to the sea as a waste.  To overcome this DEECA will need to have a strong waterway management philosophy underpinned by a strong protective culture and political will.

Recent work done for the Southern Victorian Long Term Water Resource Assessment and the CGRSWS showed that our waterways are already significantly over diverted and utilized and that mean annual yields have declined noticeably due to climate change.  Whilst recovery targets have been set for each catchment within the Central and Gippsland region, it is hard to see where the offset water is going to come from even in the medium term. In the time ahead we will see stream flows decline and the associated ecosystems will also decline with wetted perimeter being smaller providing less habitat so less robust instream communities, less fish and fewer platypus.  Essentially all the ecosystem services that waterways provide to communities will be seriously degraded.  This is likely to become very evident in the drier parts of the state – particularly north of the Dividing range and in the west.  Our waterways systems have been significantly modified over the last century to provide for irrigation waters, even into semi-arid landscapes.  As a result we have few unregulated waterways left in the state.  This has left a legacy of highly disturbed waterways that are no longer natural in their presentation but are now seasonally upside down in their flow regimes and ecology, particularly the nutrient and carbon cycles.

The next 10 years are going to be critical to preparing and adjusting to a severe change in the landscape as waterways cease to flow and wetlands dry.  No longer will we see the abundance of vegetation and wildlife along stream corridors and over wetlands as their ability to sustain life diminishes with climate change.   We must move into a far more proactive protection mode, particularly of the unregulated waterways and those that are least modified.  The activities will arise from physical protection and rehabilitation through to administrative procedures such as giving rivers full legal rights and protections under the Planning and Environment Act.  It is likely that our waterway rehabilitation works will need to shift from physical stability works, to ensuring natural flow regimes are provided, including base flows which sustain the ecosystems along with rewilding and provision of habitats.

Our Groundwater Dependent Waterways (GDEs) are particularly vulnerable to massive changes as groundwater levels decline or are over extracted.  The VWMS must be more protective of GDEs and therefore must provide an interconnection to groundwater management policies – they should not be managed as silos as they are at the moment.

We are supportive of the CMAs and Melbourne Water in the work that they have done to date on limited budgets and a controlled delivery environment.  They are doing a good job under a challenging environment and have done some good works.  But the task left to be done is enormous – we have had a huge legacy of so much disturbance to our waterways and wetlands, in addition to the impacts of climate change.  This strategy is the place to start.

Read our submission here: Concerned Waterways Alliance submission to the Victorian Waterway Management Strategy Discussion Starter FINAL