Dams of doom

Paul de Burgh-Day

IT staggers me that the subject of WATER – when it comes up on Tasmanian Times – provokes little comment: Here

This I have to say is bizarre!

Some relatively trivial threads provoke a flurry of comment – some of it I fear even more trivial!

WATER should be seen as one of the most profoundly important issues confronting us today.

Unless we wake up and realise what is happening, unless we rise up and force a change of direction, much of our island will be stuffed!

One of my Tasmanian heroes is an all too little known scientist, geo-hydrologist David Leaman.

David is my ideal scientist – a man of the highest integrity. He does his research and analysis and present the facts. He will not bend his results to suit government of corporations. Oh that all scientist had his integrity!

David has fought an incessant battle with the Tasmanian powers that be to try and prevent the destruction of this state’s all important hydrology. Over many years, his warnings have been ignored by government, by FT and by the forest/plantation industries.

They know only too well the importance of water, and they have set out to ‘get it first’.

The most serious offenders are the plantation corporations. It is they who have been destroying natural forests in upper catchments – in the highest rainfall zones of this state. They have been planting vast monocultures of very thirsty, fast growing (they grow year round with no practical variation according to seasons) blue gums. The runs are now on the board – streams fed by these catchments – in many cases year round, even through past droughts – are now dry in summer and autumn periods. Never mind the chemical contamination that goes with it – though I hasten to add here that todays so called ‘conventional’ agriculture is also responsible for appalling levels of contamination.

In the following report from the latest edition of Tasmanian Country, David Leaman spells out a very clear warning that Tasmania is rushing headlong into a hydrological doom!

The only rational course is to first know where we are.

To know this, an full and totally independent water audit of our island is essential. It MUST include groundwater resources.

Only when we know and understand where we are at, warts and all, can valid decision be made about viable steps for the future.

Those who have hijacked our water so far must be brought to account.

We must set out with total determination to get our politicians to face reality.

I am talking here about OUR WATER! OUR RESOURCE!

OUR fundamentally important and critical element of LIFE!

OUR WATER is not there for politicians to hand over, free of cost, to corporations!

TASMANIAN COUNTRY
July 25th 2008

Front page report
Dams of Doom
By Karolyn MacGregor

The Sate Government push for more large instrem dams will worsen Tasmania’s water woes, and expert has warned.

Some of the state’s catchments already were becoming “mini Murray Darlings” because of the irrigation explosion of the past decade, hydrologist David Leaman said.

Relainse on historical rainfall averages and over estimating water availability in catchments was compounding the problem, he said. Carefully planned and managed off-stream dams could be used successfully, Dr Leaman said, but evaporation would still be a concern.

“If you are pumping water into a dam you can control it and you know what you’re doing, and so does everyone else,” he said.

“With instream dams there is no control. They do too much damage and there is a lot of wastage.”

Up to 70per cent of water can be lost from dams each year through evaporation, depending on seasonal conditions, Dr Leaman said.

“As soon as you put in a major in-stream dam, you start wasting water through evaporation,” he said.

Dr Leaman’s comments came as the State Government investigates major in-stream dam developments across the state.

Plans are in place to increase Tasmania’s irrigation water storage by 50 per cent over the next eight years.

About $220 million in Federal and State Government funding has been committed to boost water development.

If successful, the developments will see Tasmania’s annual irrigation storage increased to 250,000ML a year by 2015.

Dr Leaman, who worked for the State Government assessing water catchments in the 1960s, said lack of planning was a fundamental flaw in many catchments now.

“One of the most important questions that should be asked when you start looking at water management is how how much water there is and how much can we safely use,” Dr Leaman said.

Declining rainfall over the past 30 years across much of the state due to climate change was a significant factor.

A lack of planning in the establishment of tree plantations across the state has also impacted heavily on the state’s drier catchments.

“It is an issue that no one wants to touch and ask questions about . . . the tree lobby doesn’t want this water included because then they may have to pay for it. But then there is no doubt, when you start planting large amounts of trees, you make a catchment drier,” Dr Leaman said.

“It’s not an anti-tree question. There are some catchments where the trees will make very little difference, but you can’t ignore it, you’ve got to put it into the mix.

Dr Leaman said the general perception in mainland states that Tasmania was wet, is wrong.

There are parts of Tasmania that receive a lot of rain like the West Coast, but the eastern half of the state is drier than a lot of the mainland and that’s where most of the agriculture happens and major urban areas are,” he said.

Pro[osals to pipe Tasmanian water interstate have been labelled as “insulting” by Tasmanian Farmers and Graziers Association acting general manager Chris Oldfield.

“We think this discussion is insulting to Tasmanian farmers who desperately need water in one of the worst droughts in history,” he said.

Mr Leaman agreed.

“We shouldn’t even be thinking about selling it to somewhere else until we get things sorted out here,” he said. Tasmania is in a better situation than many areas of the mainland because we do have water here, but it needs to be carefully managed.

“If we’re clever we can move our water around, but we need to be very careful about how we do it.. You need to ask what will the consequences be at both ends of the pipe.”