Friday, February 09, 2007

Australian cities have no drinking water shortage

The Australian Government has recently released proposals and papers on water, energy saving, Climate Change and The Greenhouse Effect. I have done my bit with some books and products available.

My view is that people and companies need price driven signals to help them change their behavior to use less energy and water. That is, people may want to "do the right thing" but that is difficult to do if it costs them more. Also they need the information and products to help them do it.

As an example, there is no shortage of drinking water in Australian cities. The problem is that the high quality water is underpriced and so is wasted on uses it is not needed for. It seems silly for the Federal Minister for Water, the Premiers of Queensland and NSW, and the ACT Chief Minister to tell us we have to drink recycled sewage, when they know that most of the fresh water is being used to flush toilets and water lawns, not to drink. It would make far more sense to flush toilets and water lawns with recycled water and save the good water for drinking.

This is not as obvious as it seems. I have several acquaintances who, knowing my interest in water conservation, have asked about rain water tanks. But when I suggest they should first install a dual flush toilet, they look a little confused. The new cistern will cost much less than a rain water tank, is much easier to install and will save much more water (and continue to save water even when it is not raining). But you get a larger rebate for a rainwater tank.

To do this people need incentives. My suggestion would be to announce that the aim was to reduce water consumption by half over five years and to one quarter over ten years. At the same time the price of water would be increased gradually: double in five years and four times over ten years. Householders and companies would then have an incentive to save water: those who saved water would save money.

According to "Australia's Water Resources: From Use to Management", (John J Pigram, CSIRO, 2006) 20% of domestic water is used to flush the toilet and 34% in the garden. The average Sydney household water use is 250 kL per year with a water and sewerage charge of $490.

The NSW BASIX rules require a 40% water reduction for new dwellings. This seems conservative. A 50% reduction in domestic water should be possible with no change in the householder's life style and with no need for recycling of water. This could be done by fitting a dual flush toilet, water efficient shower head, water efficient washing machine and dishwasher and a low water use garden. Reducing water use by 75% would require recycling, but faced with the prospect of their water and sewage bill going up from around $500 to $2,000 per year, the householder is likely to think it worth investing in recycling.

The alternative is that expensive large desalination and sewage plants and new dams will be built. Most of the water created will continue to be waster in toilets and on gardens. The result will be a high environmental and economic cost.

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