I was in Perth last week when the Opposition leader, Colin Barnett, announced a $2 billion water canal from the Kimberley to Perth. The proposal is to channel 200 gigalitres of water a distance of 3,700 km each year.
This is really an incredibly long distance for what, at least in a Murray Darling Basin context, could be considered a rather small volume of water.
The Living Murray initiative agreed to by the Council of Australian Governments (COAG) last year proposes to return more than twice this volume (500 gigalitres) to Murray River environmental icons as environmental flow.
The canal project is being proposed as the solution to Perth's water shortage and has been described as the "barbecue stopper" of the state election campaign so far.
I had thought there would not be any more big water infrastructure projects announced in Australia. The Barnett promise certainly goes against what has been a trend from politicians on both sides of politics: to promise to give back water to the environment rather than build new infrastructure.
It is a pity that whether the intention is to give water back to the environment (for example, the Living Murray Initiative) or to take water from the environment (such as the Kimberley to Perth water canal) proper economic and environmental studies are considered only after the promise has been made. It seems proponents of big infrastructure can be as gung-ho as the environmental lobby.
The canal project will take 200 gigalitres annually out of the Fitzroy River, equivalent to 2 per cent of the river's annual flow, and apparently without the need for a dam.
The Kimberley Environment Group is against the plan because they are concerned about the environmental impact of taking any water from their river.
Professor Peter Cullen from the Wentworth Group has indicated that a desalination plant -- already planned for construction if the Labor government is re-elected -- is a more economical solution to Perth's water shortage.
The plant would provide Perth with 45 gigalitres of water.
By comparison a single wetland working group along the Murray (The NSW Murray Wetlands Working Group) has an annual allocation of 32 gigalitres to just water red gums and wetlands.
The day before the canal announcement a local Perth newspaper suggested that clearing regrowth in the Perth catchment would increase runoff to dams by 40 gigalitres. This would almost replace the need for the desalination plant!
There has been an ongoing debate in WA about the relative impact of climate change versus vegetation thickening on inflow into dams.
Apparently about 25 years ago active management of Perth's water catchment ceased (including burn-offs and vegetation thinning) with significantly reduced surface water runoff a consequence.
That water runoff volumes will be significantly affected by land clearing is very relevant to eastern Australia, but an issue the NSW, Victorian and Queensland governments have so far chosen to ignore.
When COAG signed-off on the National Water Initiative (NWI) in June last year, WA Premier, Geoff Gallop, was the only mainland Premier to opt out. He argued WA was different, and that the NWI was too focused on Murray Darling Basin issues which had little relevance to WA.
The Murray Darling Basin may be a long way from Perth, but so is the Kimberley. The States share one land mass, one interconnected environment and can learn from each other.
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