Dam crazy - part 1

when is enough enough

John O'Grady once wrote a book called "they're a weird mob" I think an appropriate sequel today would be "they're dam crazy people"

Let me start this post with a quote from a paper on "FLOW RESTORATION AND PROTECTION IN AUSTRALIAN RIVERS" published in 2003

"Since 1857 new Australians have constructed many thousands of weirs (3600 in the Murray-Darling Basin alone) and floodplain levee banks, 446 large dams (>10m crest height) and over 50 intra- and inter-basin water transfer schemes to secure water supplies for human use."

So we've been building more dams than a family of beavers and we still haven't got enough water? Leaving any theory out of this and just looking at this in a "black box" way it is pretty apparent to the most common person in Australia that banging the same drum is not going to produce a solution.

Instead, all that seems to have resulted from that is increased spending, increased requirement of management and increasingly degrading our environment.


Despite these negative effects our government seem "hell bent" on pushing through the same strategies which have been shown to be inadequate and not provide sustainable answers to the question.

It seems that no matter how much we build dams we're always playing a game of catchup, but its now getting worse as now (due to the expansion of our population and urban sprawls) we find that we're rapidly running out of locations where we can actually put a dam without needing to drive people out of their homes or flood productive grazing and farmlands.

Actually this isn't a new phenomenon, back in the 1970's in the Gold Coast hinterland a small town in the Numinbar valley was "resumed" a dam built and the valley flooded. This dam was the Hinze dam and it served the population of the Gold Coast well for over 20 years.

But in the scale of things 20 years isn't really a long period and now the population is living on a dependency of "good years" of rainfall as it was shown in 2003 that if there is just 2 years of low rainfall that the dams run very close to failing to meet demands.

In fact if it was not for the evocation of water restrictions (close to martial law) on the population its certain that the dams would indeed fail.

This image was taken from a locatoin well below the ideal water line of the Hinze dam during the water crisis of 2003, and infact the dam got so low that some of the traffic signs from the immersed town began to appear.

Chicken little cry of "drought"

There's a drought there's a drought... The common thing is to blame this on drought and suggest that we're in the grip of the worst drought in living memory or some such nonsense. The solution to the problem is often ingeniously put forward that: we need to (wait for it ... drum roll) build more dams to drought proof the region.

Gosh ... that hasn't been tried before. Actually we've been trying to "drought proof" ourselves by building dams since the beginning of the 20th Century. Melbourne Water even has a nice reference to this on their history page.

We all know that Australia is a dry country, from the poems of Dorothea Mackellar through surveys as done by our early pioneers (Goyder) to our iconic images, we know we are intrinsically a dry land with limits to our water supply.

So why is it then that lack of rain is a "surprise" when it happens?

Short memory or media created social belief?

Perhaps its down to our short memories, perhaps because we're all so media fed we've forgotten how to remember ... I don't know. There seems to be a case however, that people believe what they're told and the the group believes what the group leaders tell them is true.

Firstly lets look at some data. Below is a chart showing the rainfall at Southport for around 100 years.

Two things are clear looking at this graph; firstly there are some serious spikes in the rainfall history with a big spike in around 1976 (when we had our worst flooding on record) and secondly that there is an overall trend up in rainfall around the middle of the period.

This data amount is short really (after all its only a hundred years) but it could well mean that its been drier than it has been in the last 50 years and that its a little early to be wondering if this is climate change or some other trend.

So what's changed?

Part of the problem is that the population goes up as 1) we move more people into our cites from the countryside 2) our population in Australia grows.

To take things from the general to the specific, lets pick a case study.

The Gold Coast and Brisbane represent a large fraction (like most) of the population of South East Queensland.

Since 1960 the population has grown to nearly 10 times its number, so when the Hinze Dam was being planned I think its fair to say that no one was thinking that the population would grow to around half a million people. Especially since at the time there was the "Little Nerang Dam" which was built just a few years earlier to supply the region.

Looking around at the topography there are not many clearly obvious sites for another dam, the ranges are close. Have a look around your self...


View Larger Map

go much further west and its too dry, go much further north and you hit Brisbane.

With more and more pressure (may someone please tell me why and where it is comming from?) to move to the area there is pressure to build more dams. Currently there is some targeting of the Mary river around the north side of Brisbane but there is strong opposition to that for a number of good reasons.


Planners seem to be bent on more dams as the solution to the problem (despite it not having solved it yet). There have been quite a many proposals for Dams in the South East Queensland regions which have either been scuttled, shelved, renamed or on the go.

But it continues to look bad for dams as if its not public opposition it internal problems. For example one of the requirements for a project these days is (thank god) that there must be an economic fesability study done to demonstrate that the project is justifiable. This seems to be quite an obstacle, as it is seldom found that the dam will provide water at a price which the market will accept.

For example One study done for the government into a previous dam proposal (Paradise Dam) suggests that it will not be economically viable and that water needs could be met with alternatives.

Alternatives ...?

You mean there is an alternative to building more dams? One thing is for sure, while we may have had droughts in the past we weren't as reliant on dams as we are now. In fact I'm not even entirely sure that they make good sence in our environment / geography / climate. The idea after all has come from Europe, where topography similar to the (quite successful) Little Nerang Dam exists.

You don't have to look far in outback Australia to find a house with a tank on the side to store rain water.

Now before you get steamed up on the problems with tank water I'd like to point out something important... diversity.

Something which seems to have come from the modern world is the destruction of our understanding of diversity of supply. We get all our water from reticulated water supply, we buy everything in Shopping Malls, we all seem to get our ideas from TV ....

Think about it ... Do you eat only one thing?

Like do you eat only bread or only meat?

Having a rainwater tank adds to your houshold water supply, you may not want to drink it, but do you really need to be flushing your toilet with water treated to high "drinking water quality" standards?

In part 2 I would like to present more about the alternatives and explain more on why I just don't get the Australian (government) mentality towards dams.