Water Water everywhere...

...and not a drop to drink

On Saturday 3rd March a rally was held to protest Gunns proposed mill.

While the last rally focused on dioxin pollution of the Bass Strait. this rally focused on Gunns proposed use of 26 Gigalitres (thats 26 billion litres) of fresh water per year.  Gunns have struck a deal to pump their water straight from the Trevallyn Dam which provides Launceston's fresh water.  

1. Launceston's entire domestic water use is 29 Gigalitres. 
2. Water from the dam is also used to supply industry, agriculture and to produce hydro-power. 

The Trevallyn Dam only holds 8.6 Gigalitres, which means that the mill would empty the dam entirely three times a year. Fortunately, this figure isn't as alarming as it sounds because Trevallyn Dam itself is fed from the Great Lake, one of Tasmania's two mega-dams, with a holding capacity of 3 Teralitres (or 3000 Gigalitres). 

Gunns claim that their water usage would only be 1% of the flow of the Tamar river. However, this figure isn't as re-assuring as it sounds because the Great Lake isn't at full capacity.  In fact, its never been at full capacity.

According to figures supplied by Hydro Tasmania, the level of the dam has been:

• 2000,     62.2%
• 2003,     37.0%
• 2005,     32.3%
• 2006,     32.6%
• 2007,     15.7%

This is alarming.   In fact, more alarming than it sounds.  According to Hydro Tasmania,  the Great Lake's levels are supposed to fluctuate over decades, rather than years.  While it would take decades to fill the Great lake, in just one year its levels have almost halved. To give you an idea of the severity of the situation:

• There isn't enough water in the Great Lake to flush out a blue-green algal bloom.  Instead, filtration equipment has to be used to filter out the toxic algae
• There isn't enough water to run Tassie's hydro power stations at their normal rate.  In fact, Tassie is now importing coal fired power rather than exporting hydro power as it used to.  This will cost Tasmania $70million.

Why has the level fallen so dramatically? Two reasons, I believe:

1.  Tasmania is experiencing a dry period, yet it can hardly be called a severe drought.  Unlike the mainland, Tasmania's dry spell has only been going for a few years.  What will happen if Tasmania experiences a 10 year drought like Victoria?  

2.  Thousands of hectares of plantations have been planted in the Great Lakes catchment area. As these young trees grow, they absorb billions more litres than the mature forests or farmland which they have replaced.  This effect has already impacted on Southern Victoria with devastating environmental and economic consequences .

The Pulp Mill's effect on Water levels:

Lets look at what the level would be if Gunns Mill had been operating since 1990. 

• Right now the Great Lake is at 15.7% capacity, meaning that it currently holds 471 Gigalitres.   
• If the mill had been operating since 1990, at 26 Gigalitres per annum , the mill would have consumed 442 gigalitres.

How much water would be left in the Great lake?  Precious little.

Things look like getting worse, not better.

• Climate predictions are that Northern Tasmania will become dryer, not wetter.  
• If the mill proceeds plantation plantings will ramp up, meaning that less and less water will make its way into the Great Lake

Can the Tamar Valley afford 26 Gigalitres of fresh water per annum and increased plantations in the catchment area?

You decide.

      The crowd gathers on land and water to protest. 3rd March 2007