The amount of water that flows off Australian rooves is around 900GL each year regardless of climate change. With rainwater yield from a roof, what you see is what you get. This compares with rainfall in catchment areas where what you see is three-times what you get (a 14% decline in Perth’s rainfall led to a 52% decline in runoff into its catchments – must have those pesky trees).

85% of Australians live within 50KM of the coast and coastal rainfall is probably the most reliable source of water.

About one-half of the water that falls onto roofs can be economically captured in rainwater tanks and used in replacement of mains-supply drinking water.

This will be sufficient to supply 20% - 25% of the nation’s drinking water requirements.

Well might Governments, as Jennifer notes, “be frightened to make some of the necessary and practical decisions which could alleviate some of our water problems because they might be unpopular”.

What’s unpopular about rainwater tanks?

The National Water Commission is one Government agency that stands ready to take action should the integrated water cycle be threatened by rainwater tanks.

Says the Commission: “If rainwater tanks were to be adopted on a large scale such that their existence impacts significantly on the integrated water cycle, consideration could be given to setting an entitlement regime for this class of water.”

Sounds like a dry argument to me.

Greg Cameron

Jennifer, what a dangerous and misleading statement you make in your article: "The boogey man is now climate change, and according to the popular press and some meteorologists, it is responsible for the current drought."

I would suggest that you research further afield amongst the scientific community (climate scientists for a start) before declaring your position as a climate change skeptic. I would also suggest that from your statement "the popular press" your reading on the subject has been very limited.

Australia is a dry country, there is no doubt about that but activities by humans have changed weather patterns (climate change)and therefore the amount of rain that we receive has changed.

Historically, (read Jared Diamond) civilisations have perished because of unsustainable consumption of resources, which have ulitmately changed weather patterns and created permanent drought. What we are now experiencing here in Australia is not dissimilar.

What we do have now is the chance to alter the pattern by stopping our destructive behaviour burning fossil fuel for our energy - it's as simple as that!

Alternative energy represents a paradigm shift away from "dirty energy" and Australia has more than enough solar and wind power to energise our nation.

It will take a bag full of money and a huge committment by all sections of our community but if the Europeans can do it with their limited renewable energy sources, then we can do it sitting down.

We need to make this shift - for the sake of our children.

Phil Bramley
Tanja
NSW

“In summary, there is a water shortage in Australia but rainfall has not been exceptionally low and it is indeed drawing a long bow to blame climate change.”

Agreed Jennifer. But we still need to address the greenhouse gas emissions / climate change issue as best we can, not because our emissions are significant on the world scale, but because we need to set an example for the US and China and thus pressure the big emitters into stronger action. And we certainly must NOT be seen to setting the opposite example, of business (and very high per-capita emissions) as usual.

“But perhaps the water shortage in our cities has more to do with a lack of investment in water infrastructure coupled with a steady increase in population, than global warming?”

Absolutely. There has certainly been a lack of investment in water infrastructure, and thus a failure to keep up a secure supply to the rapidly growing population. But of much more significance is the rapidly growing population itself….that has stressed one of our most basic and eminently renewable resources to the point that the supply is no longer sustainable.

We need to do all sorts things to improve this situation. And one of the biggest and most fundamental, and relatively easy, steps has surely got to be to slow and then stabilise this population-driven demand.

We should thus be gearing immigration down to at least net zero over the next few years…. and killing off Costello’s baby-buying bonus once and for all.

How crazy is it to continue to have rapid expansion of all things human while our basic resources (life-support systems) are under great stress?

Good post Greg.
The national water commission is obviously worried about the loss of state & council income, if it looses too much of the water rip off.
It can't be about any ecological effect. If we caught all the water from our roofs, the run off from built up areas would still be much more than natural, for the area.
Of course the bull sh#t runs much deeper than the water.

Jennifer your piece is quite hilarious. I mention just a few holes:

“Geological history and modelling, including by the National Center for Atmospheric Research in Colorado, indicates that as the world warms it will generally get wetter. Yet we have a drought in southern Australia.”

The word to pay attention to here is generally. It does not mean everywhere will be wetter. The drought in SE Australia is likely caused by a weak El Nino and also cooler than normal sea surface temperatures over the NW of the continent. This has starved inland areas of the NW cloud band that in the past preceded cold fronts in low pressure troughs, often delivering heavy rain. Heavy rain means run-off, something we haven’t seen for almost 6 years over Sydney’s water catchment. Nonetheless we cannot entirely dismiss the possibility that human induced climate change is partly responsible for recent changes in weather patterns.

“Rainfall may not have been exceptionally low, but there is certainly a water shortage and not just in the Murray Darling Basin. .....perhaps the water shortage in our cities has more to do with a lack of investment in water infrastructure coupled with a steady increase in population, than global warming? Perhaps water shortages in the Murray Darling Basin have been exacerbated by how we are now managing the landscape based on a past fear of rising ground water?”

The lack of water in the Murray is due to extremely low rainfall this year. Why? Because last winter was characterised by an almost complete absence of cold fronts that normally deliver snow to the Snowy Mountains. It was one of the worst snow seasons on record, like 1982. You are correct in saying that reducing CO2 emissions will not solve our drought. However, the supply of fossil fuels is fixed and will eventually run out, so there is no harm in starting to do something now, in addition to measures to harvest rainwater. In addition, as Ludwig suggests, stop the rising population and we may save ourselves the need to invest in costly, energy wasting and polluting infrastructure.

You guys at this forum really know how to argue logically - not!
Robg, I think your response is so lacking in logic and so misleading it is truly sad. You actually agree with me that as it warms the world will generally get wetter and that low inflow rather than low rainfall is the problem for the Murray. Your El Nino explaination is not inconsistent with the idea of changed wind patterns.Your explaination may have more relevance to Sydney. But probably not to southern Australia more generally.
As regards fossil fuels running out before we move beyond the oil age... well you are a pessimist.