An analysis of the scale of the proposed desalination plant on other water augmentation options within the Victorian Government’s Water Plan. There is a real question mark over whether the Government has any real intentions of making significant use of recycled water!
Excerpt from Sections 1 & 2
The scoping document produced by the Department of Planning and Community Development (1) for the Environmental Effects Statement (EES) of the proposed desalination plant, being part of the governments Water Plan (2), requires that the scale of the plant and its impacts on other augmentations within Government policy must be considered.
p14 - ‘the EES report should include:
• A description of the project’s objectives and rationale, as well as its relationship to strategic policies and plans’
p20 - ‘describe, explain, and if relevant also assess, feasible concept alternatives for:
• the scale and staging of the plant development’
The EES rightly states that; ‘Scale is without precedent’, this plant will be larger than any currently operating worldwide, and as such it’s place within Greater Melbourne’s water supply network and its effect on other supply options must be considered. Further, the economic and environmental effects of a single plant of this unprecedented scale would be proportionately reduced if the scale could be reduced while still allowing the governments to satisfy overall system needs, perhaps with the addition of other augmentations. Other policy initiatives such as recycling are recognised as having beneficial environmental spinoffs and should not be excluded by the adoption of excessive scale of desalination.
p21 - ‘Economic effects …. In relation to a plant capable of producing up to 150 or 200 GL …..
• Explain the considerations underlying the proposed scale and potential staging of the desalination plant, in terms of supply capacity”
This modelling and analysis of Government data and referenced studies confirms the following:
• In a future scenario approximating a continuation of the last 10 years of drought water storages will be spilling or close to it for typically five years with desalination operating at a 100 GL or 150 GL scale. Additional augmentation of 55GL to supply, above these desalination levels, leads to storage levels at or near spilling for 25 to 40 years.
• In a future scenario where the lowest on record 2006 inflow repeats every third year, demand returns to unrestricted levels under permanent water saving rules, and desalination scale is at 150 GL, additional augmentation produces a similar result. A 55GL additional augmentation has storages at or near spilling for more than 20 years.
This presents a compelling case that the proposed scale of this project is excessive and will have an adverse effect on the uptake of alternatives that are part of current Government policy or may be part of future policy.
Consideration also needs to be given to this scale of desalination tying up storage infrastructure, in particular Cardinia Reservoir, and the adverse effects that this may have on the ability to implement other supply options.
Government policy is rightly to diversify and boost supply to meet future demand, however the current proposal looks like restricting diversity largely to a single option, desalination. Given the Victorian community has considerable economic investment in and desire to implement supply options such as recycling, and that it is Government policy to implement large scale recycling, this scale of desalination seems at odds with the communities expectations of their Government. It should be noted that Government does not have a mandate to implement desalination, in fact it has a mandate that it should be a last resort.
The community also requires their Government to limit Victoria’s greenhouse gas emission to the extent practicable, in order that future generations do not bear too large a costs from climate change. By limiting augmentation largely to the option that produces the greatest greenhouse emissions, the offsets required are significantly larger than would be the case with a more diverse range of supply options. This will mean that a greater quantity of feasible renewable energy is tied up in water infrastructure, and is thus unable to be used to offset other existing Victorian emissions.