Gnangara Mound

It has become known that the EPA is recommending (or insisting on) the shutdown of WaterCorp bores currently drawing water from the Gnangara Mound.
According to the WaterCorp submission to the ERA water price inquiry we draw 150 GL of water per year from the Gnangara Mound, remember this equates to more than three times the proposed new Kwinana Reverse Osmosis Desalination Plant (KRODP) and what proportion of this the EPA want shut off is not clear.
The implications of this are that the 45 GL of water production from the proposed new KRODP might immediately be cancelled out and we will be at square one again.
Just half a billion dollars more in debt.
The EPA is concerned that falling water tables are impacting on wetlands.
Perth people might have some hard choices ahead to balance maintaining some urban swamps as opposed to investing up to a $Billion in new dealination plants.
We think more could be done to engineer recharge zones to increase the proportion of rainwater that goes into the mound.
We would like to see an impartial expert report into Gnangara Mound hydrology, water supply potential and what the options are to balance community needs with the environment.
How many competing bureaucracies do we need all interfering in our water supply ?

Gnangara Pines
Recent news about a plywood industry based on pine plantations on the Gnangara Mound make interesting listening as GovWater trumpets its genius at proposing to clear the pines over the next 30 years  thus improving the capacity of the mound by some 40GL a year in the future.
We wonder if there has been any proper assessment of the current value of the pines taking into account their impact on the Gnangara Mound which at 40 GL per year is almost exactly minus $350Mill, the cost of the Govts. proposed KRODP, thats their estimate, Perth Water Users says more like $500Mill assuming normal cost over-runs.
We wonder what real value this much ballyhooed timber industry is based on; a resource the true cost of which starts at a negative half a billion dollars.
We wonder if another option should be considered, that of accelarated removal of the pines and their sale as lumber.
The UWA Water Resources people estimate that clearing the pines over a decade with the resulting land being used for a mix of  housing and native bush, there would be 130 extra GL of water per year.  Think on that !!
There is another issue, what is the world price for this type of lumber if we did not have the pines and had to import the lumber.
Another path would be to import the plywood.
Both deserve assessment taking into account the $500Mill KRODP cost.
The chart at left shows declining New Zealand export pine log prices over a decade. Prices in $NZ per cub m fob Data from the NZ Ministry of Forests web site.
Perth Water Users look forward to a real economic analysis of the value of the Gnangara Pines balanced against the value of groundwater pumping potential that the pines cancel out every year.
If GovWater is pricing all incremental new water at KRODP prices then we are looking down the barrel of colossal investing in desalination plants, in an time of rising energy prices and we will end up with an increasing part of our water supply subject to strike action.
What a scenario, the Ernie Bridges pipeline looks better all the time.

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