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Water Pollution

Dr Rosalie Woodruff MP

Dr Rosalie Woodruff MP  -  Thursday, 28 November 2019

Tags: Irrigation, Water Restrictions, Oxygen Levels, Algal Blooms, Derwent River

Dr WOODRUFF (Franklin) - Madam Speaker, we heard yesterday that Hobart could face drinking water restrictions and that farmers will need to cut back their water usage through irrigation schemes. This is very disturbing news, particularly for people who live in Hobart and who are labouring under the pretext that TasWater and Tas Irrigation and this Government would have worked out a situation to have safeguarded drinking water supplies for people in Hobart.

We know when it gets hot and dry this summer we will be almost entirely reliant on the Derwent River to supply water to the greater Hobart area and also to supply water for irrigation. That is, treated water that goes to irrigation that gets paid for to be treated before it goes to irrigation. Despite our complete reliance on that water, the Government appears very careless about the pollution that is entering the waterways and that is tainting our drinking water supply and damaging the environment.

We have been warned countless times of the risk of high levels of nitrogen and phosphorous entering waterways. These compounds lead to algal blooms and can make water unusable. We have seen that in the upper reaches of the Derwent. It has happened. We have even had reports of atrocious levels of nutrient pollution from the Wayatinah and Florentine hatcheries that were published early this year from the Saltas hatchery there.

These facilities were only recently required to perform any form of filtration to the megalitres of waste that are pouring from their factories into the upper reaches of the Derwent. Despite that, the EPA has waved through another large hatchery right next to Meadowbank Lake, which supplies water to Hamilton, the Derwent and ultimately to Hobart.

The esteemed scientist, Christine Coughanowr, stated that she was prepared to be:

Impressed by the effluent of the quality of Tassal's new hatchery.

But she also said she was:

Really surprised by the high level of nitrates and salinity that appeared to be produced.

Local seventh generation farmers, the Headlams (TBC), have been shocked to hear of that development. They know that the volume of waste produced by the hatchery that is intended to be used as irrigation will eventually end up in their lake, their drinking water and ultimately into Hobart's drinking water.

The Headlams know that their land, where they have lived for generations, and they know the effect that the proposal will have on it. The hatchery was approved by stealth, with a piecemeal process that was designed to fly under the radar and get approved as quickly as possible. There is very extensive concern in the communities surrounding the Headlams and the Central Highland Council about the processes around this approval.

Why is the EPA bending over backwards to approve Tassal's hatchery when we know it will contribute to algal blooms and add even more nutrients to a system already close to breaking point? The question not being answered by anyone is: what happens when Tassal's reuse dam is full and the paddocks are irrigated? Are they going to shut down the hatchery and let their products die or are they going to continue running the pivot irrigators, pouring the nutrient-rich waste into the Meadowbank and Derwent Rivers? The latter, I think, and so do those in the headlands and other people in the community. What we are worried about is the height of the summer when the rivers are at their lowest flows and we will feel the brunt of global heating with more record temperatures and an Upper Derwent experiencing the possibility of a catastrophic algal bloom.

Water, as minister Barnett said today, is indeed liquid gold, but we are squandering it and putting the security of its quality at risk with unfettered growth of the fish farming industry and this new mega-sized hatchery, which has raced through the approval process without the opportunity for proper oversight or independent assessment. We are now risking a Derwent River crisis with the massive fish farm expansion planned in Storm Bay, likely to cause nutrients to flow up the Derwent with the saltwater and that water is going to be met by the fish waste flowing down from the hatcheries, resulting in likely algal blooms and a crash in dissolved oxygen.

What I do not want to see is our beautiful Derwent estuary lined up with dead fish like the Murray River, because that is where we are heading with the current management of our waterways. It is not good enough and we are going to keep asking questions, despite the fact that this is the last opportunity in parliament this year. We will continue to ask this because it will only become hotter and a pinch on water availability is yet another thing that we are going to be talking more about as a community because that is where we are heading with global heating. They are the process and the independence we need to make sure we can have these systems working for us, not for business interests only.