Great Artesian Basin

05 Jun 2007 questionsarchive

I seek leave to make an explanation before asking the Minister for Environment and Conservation a question about the Great Artesian Basin.

The Hon. J.M.A. LENSINK: The Great Artesian Basin Sustainability Initiative (GABSI) is a joint commonwealth state funded program, the main purpose of which is to achieve an increase in artesian pressure as well as more sustainable infrastructure and groundwater management through the capping control and decommissioning of bores.

A report into the scheme published in October 2003 advised that, at the time of reporting, New SouthWales had exceeded its five-year target and South Australia had made ‘more modest gains in pressure’.

The Great Artesian Basin Strategic Management Plan aims to save 211 gigalitres over a 15-year period. The opposition has been advised that, because the water is coming out of the ground at such extreme temperatures, the polypipe used in the cooling grids is failing and that fibreglass resins used to rehabilitate and decommission bores is failing. Urgent attention is needed to ‘uncontrol’ bores which are a threat to occupational health and safety and to the environment. Some 20 bores remain uncapped or rehabilitated and one bore is seeping 14 litres per second which, on my calculations, is more than 20 000 litres a day or nearly 7.5 million litres. My questions to the minister are:

1. Will she provide a progress report of GABSI?

2. Will she advise whether the government is considering alternative material which is better able to withstand the pressures and temperatures?

3. Did South Australia fully match the commonwealth funding?

4. Is phase 3 of the program the final stage?

The Hon. G.E. GAGO(Minister for Environment and Conservation): Indeed, GABSI commenced in 1999-2000 and, as members know, it is jointly funded by the state and commonwealth governments. The two components of the initiative are the well and bore drain replacement programs.

To date under the initiative, nine wells have been decommissioned, three rehabilitated and 12 replacement wells drilled, saving 6.6 megalitres per day, which is 2 407 megalitres a year.

Work has commenced on the drilling of a replacement well for Mt Gason bore on the Birdsville track. The original Mt Gason bore will be decommissioned on completion of a replacement well. There are 37 uncontrolled flowing wells remaining in the Great Artesian Basin, of which 29 wells are considered eligible for initiative type funding. The bore drain replacement program has delivered approximately 185 kilometres of pipe and associated tanks and troughs to 22 pastoral leases, saving an estimated 53 megalitres per day—and that translates to about 19 345 megalitres a year.

As members can see, there are quite substantial savings from these significant works. The benefits which have resulted from investments under the initiative include obviously greater security of water supply for existing users and groundwater dependent wetlands, including the mound springs and other related ecosystems; improved management of pastoral leases; and, of course, increased availability of water for new development and users. A business plan for investment in risk management and infrastructure in the Great Artesian Basin has been prepared by DWLBC, and its aim is to complete outstanding works under the initiative involving well rehabilitation, removal of bore drains and construction of cooling grids; investigate the failure of the fibreglass case wells where that has occurred; and investigate the possibility of establishing a contributory funding scheme for pastoralists to take up responsibility for the long-term maintenance or replacement of bores in the basin.

An economic analysis on the feasibility of those options for a bore insurance scheme has also undergone some preliminary work. The issues that have emerged in relation to the failure of several bores with this fibreglass casing and a work program have been submitted with the business plan to investigate the cause of the failure. It is very disappointing.

We initially spent a great deal in putting in a very high quality fibreglass casing. We could have gone for a much cheaper option but went for the one which was suggested to be the best product of the day.We went for that option, rather than going for anything cheaper. Obviously, we put a lot of work and consideration into the type of casings used.

Issues have emerged in relation to the depositing of a carbonate material and also algae blooms on the cooling grids used to lower temperatures—the water comes out at a very high temperature in some of these water systems—and a water circulation device and epoxy resin have been trialled on a cooling grid to reduce the depositing of that carbonate material. That is work in progress and we are monitoring how that is going. In terms of future well maintenance, obviously the responsibility for bores resides with pastoralists and lessees of the land, and acceptance of this responsibility is obviously constrained by the high replacement costs—around $250 000 to $700 000 per bore. Members can see that it involves large amounts of money.

The higher costs are incurred by the bores which require deeper placement, and also the higher pressure and the higher temperatures that can be associated with those bores. In developing a business plan, DWLBC has investigated the feasibility of potential funding models for contributory funding schemes, as I mentioned, to help them take up longterm funding responsibilities in the longer term. In terms of the future phasings, they are under negotiation with the commonwealth government and the chamber will be informed when that has been finalised.

The Hon. J.M.A. LENSINK: I have a supplementary question arising from the answer. Can the minister advise whether the business plan includes a contingency for pastoralists who did not previously take up the offer to participate in the scheme?

The Hon. G.E. GAGO: I do not have the answer to that question. I doubt it, but I am happy to check and bring back a response.

Thursday 18 October 2007

In reply to the Hon. J.M.A. LENSINK (5 June 2007).

The Hon. G.E. GAGO (Minister for Environment and Conservation, Minister for Mental Health and Substance Abuse, Minister Assisting the Minister for Health): I have been advised that: Provision has been made in the business plan for the inclusion of pastoralists who previously did not take up the offer to participate in the bore drain replacement scheme to replace open bore drains with piped water distribution systems. The contingency covers up to three pastoral properties, one major and two with minor systems.