EYRE PENINSULA WATER SUPPLY

In reply to Mrs PENFOLD (Flinders) (25 September 2007).

The Hon. K.A. MAYWALD (Chaffey—Minister for the River Murray, Minister for Water Security, Minister for Regional Development, Minister for Small Business, Minister Assisting the Minister for Industry and Trade): SA Water has provided the following information:

The groundwater used to supply most of Eyre Peninsula has naturally occurring levels of Calcium Carbonate that leads to the water being particularly 'hard', and can be associated with scaling of pipes and fittings.

SA Water undertakes regular monitoring of water quality on Eyre Peninsula. The results of these analyses show that total hardness (measured as calcium carbonate) has dropped in the water supply to Streaky Bay, Ceduna and Wudinna over the last 10 years.

SA Water's investigations indicate that elevated water temperature in customer private pipe system is the main cause of scaling. The problems generally occur if polyethylene pipe is used to transport water over long distances by private landowners. When polyethylene pipe is used on the ground surface or in shallow trenches (i.e. less than 200mm below the surface) water in non flowing or low flowing situations can absorb large amounts of heat, giving rise to increased scaling and precipitation problems and in extreme circumstances, can block the pipe. Polyethylene storage tanks, particularly if they are a dark colour can also have similar problems.

SA Water has informed the public about this issue through communication with councils, schools and the community across Eyre Peninsula. SA Water recommends that private polyethylene piping be buried greater than 200mm below the surface to reduce the likelihood of water heating.

SA Water is currently working with the community to develop a longer term water plan across the Eyre Peninsula.