Rainfall in the state has reduced 75% over the last ten years, which far exceeds the worst case predictions by the CSIRO when they modeled the effects of climate change.
It is therefore appropriate that the Victorian government take fairly urgent action to address this very serious issue that now impacts all Victorians. The question is, have they got the right strategies in place?
The government's Water Plan, also labeled as “Our Water Our Future” details the following key initiatives:
- A new desalination plant for Melbourne
- Modernising Victoria’s Food Bowl irrigation system to capture lost water for farms, the environment and Melbourne
- Expansion of Victoria’s Water Grid
- Upgrading Melbourne’s Eastern Treatment Plant to provide over 100 GL of recycled water in 2012 and assessing a range of alternative uses of this water
- Supporting new and existing water conservation programs for homes and industry.
While elements of this plan seem reasonable, the projects arising out of it to date are highly questionable.
The desalination plant
The proposed desalination plant at Wonthaggi is supposed to provide 150 gigalitres of water per year – enough for one third of Melbourne's consumption. However, this plant will require 90 megawatts of power to run. This translates to 1 terawatt hour per year (1,000 gigawatt hours).
The government has stated that they will source renewable energy for this, but there is significant risk that they won't be able to get enough.
Premier John Brumby stated on ABC Radio 774 on 26 June 2008 that the desalination plant would cost less to install and use less energy than installing domestic rainwater tanks with electric pumps. The information he based this claim on appears to be incorrect. Calculations on domestic pumps supplying one million households indicated that they would only consume 365 gigawatt hours per year, less than half the amount required to power the desalination plant.
More energy is also need to pump water from the desalination plant to Melbourne.
Stopping logging in Melbourne's water catchments would yield about another 30 gigalitres per year.
Modernising Victoria's irrigation system
This $750 million project is part of a government water strategy, which would also modernise infrastructure in the region to save 225 billion litres of water now lost through evaporation, seepage and system inefficiencies.
While replacing fixing leaks and water losses in irrigation infrastructure is a good thing, the Victorian government has announced a plan to pump water from the Goulburn River, which is in the water-deprived Murray Darling catchment, over the Great Dividing Range to Melbourne.
The two glaring problems with this are:
There is not enough water in the Goulburn River to take more out without critically endangering both the Goulburn and Murray Rivers.
- The water taken out, estimated to be 75 gigalitres, will be pumped over the Great Dividing Range to Melbourne, which will result in more carbon emissions
Expansion of Victoria’s Water Grid
The concept behind “expanding the water grid” is to provide interconnections between river systems and storages across the state of Victoria.
The claimed benefits for this include:
Increase the security of water supplies by diversifying the sources of water available for communities connected by the Grid
Enable water to be traded more readily, by making it easier to transfer water to where it is most needed and valued
- Increase the value of supply options (current and future) by increasing the flexibility and diversity of uses.
- The expanded Victorian Water Grid will allow more water to be transferred between water systems.
However, around 10,000km of expensive new pipeline is required to create this network.
There are social equity issues with taking scarce water from rural areas to for Melbourne's domestic water supply.
Environmental flows have not been provided to the Yarra River which flows through Melbourne, contrary to scientific recommendations and a previous government commitment. This environmental flow should be provided to ensure the health of the river.
Carbon emissions are generated every time water pumped through a pipeline unless renewable energy is used for this.
Upgrading Melbourne’s Eastern Treatment Plant to provide over 100 GL of recycled water in 2012 and assessing a range of alternative uses of this water
This proposal is a good one. However, Melbourne produces around 320 GL of wastewater per year. Around 400ML per day is pumped out from Gunnamatta Beach outfall alone.
The government should set a higher target for recycling water of at least 200GL, and eliminate ocean outfalls.
Latrobe Valley power stations consume 140 billion litres (GL) of water per year, so recycled water could be used for this purpose rather than drinking water.
Supporting new and existing water conservation programs for homes and industry
This initiative is commendable. However, Melbourne's daily water usage is still quite high at 277 litres per person per day. A reduction to 150 litres per person per day is achievable, which would greatly reduce demand for water, and expensive new infrastructure to provide it.
The Brumby government has embarked on an expensive plan to address Victoria's water shortage, with a particular focus on ensuring Melbourne's water supply, with some severe impacts on rural areas resulting. In particular, the loss of water from the ailing Goulburn River, and the building of an energy hungry and polluting desalination plant at Wonthaggi will have major impacts to these regions.
The entire Murray Darling River is now at risk. Rather than taking more water from the Goulburn River, increased environmental flows should be provided to both the Goulburn and Murray rivers.
The $4.9b spending on these water projects will be passed onto Victorian taxpayers, with water bills increasing by about 15% already in 2008. It is projected that water prices will double by 2012 to pay for these projects.
Simple proven measures to increase water supply by protecting water catchments from logging are being ignored.
Melbourne's water supply needs would be better and more cheaply met by:
reducing water consumption through increased efficiency measures
stopping logging in water catchments
major investment in domestic water tank systems, which have the added advantage of being installed incrementally
harvesting, storing and using more of the 450 GL of storm water Melbourne loses per year
recycling at least 200GL of sewerage per year and stopping ocean outfalls.
These initiatives can be funded from recurrent spending at cheaper rates (10%) than funds for giant projects such as the proposed $3b desalination plant (20%) under a Public Private Partnership.
The other worrying aspect of the government's water strategy is the apparent lack of supporting information on how their decisions were made, and grossly inadequate public consultation during its development.
The water strategy has been delivered as a fait accompli by government; they are not showing any signs of investigating lower risk and cheaper, more distributed alternatives.