Page 2822 - Week 10 - Wednesday, 14 August 1991

Next page . . . . Previous page . . . . Contents . . . . Debates(HTML) . . . . PDF . . . .


ELECTRICITY AND WATER (AMENDMENT) BILL 1991

Detail Stage

Consideration resumed.

MR BERRY: As I said, Mr Prowse requested information in relation to this matter, but he was advised that it would be sent to the respective ministries. Mr Prowse also suggested that fluoride could be mixed with another substance to achieve an acceptable tolerance of fluoride concentration - half fluoride and half something else. The something else is the problem. This would need further investigation. It is a serious matter.

One does not just add substances, inert or otherwise, without planning and making sure that it is not a threat to public health and, of course, is in line with informed sources, as was the case in relation to fluoride. It is clear that the Government decided upon the addition of fluoride to Canberra's water supply in accordance with the recommendation of the National Health and Medical Research Council. One does not consider adding a substance to potable water lightly. The acceptability of a substance, whatever it might be, would have to be examined very closely. I would require that it be considered closely and I suspect that that would take some time.

We then come to the issue of whether or not the equipment that is currently in place could dose the water within acceptable tolerances. The view that I take, from the information that I have in front of me, is that plus or minus 10 per cent is an acceptable tolerance. I will hand around for the information of members a table of fluoridation tolerances which sets out the current arrangements and the proposed new equipment. I will leave the Googong dosing equipment out because it is adjustable, although it services only 10 per cent of the water. I will stick to Stromlo because it services the larger part of the water supply. For a target concentration of 0.5 milligrams per litre, based on a flow rate of 60 to 120 megalitres per day, the upper limit would be 0.7 and the lower limit would be 0.3, and that would be for 40 per cent of the time. That is the first column. The tolerance is plus or minus 40 per cent. That, in my view, is not an acceptable tolerance.

In respect of a flow rate of 120 megalitres a day or 120 megalitres plus, for 60 per cent of the time we could have upper limits of 0.6 and lower limits of 0.4. That is plus or minus 20 per cent and, in my view, that is not an acceptable tolerance either. In respect of the new equipment that is proposed, again for the target concentration of 0.5 milligrams per litre, the upper limit would be 0.55 milligrams per litre and the lower limit would be 0.45 milligrams per litre. That is for all flow rates for all of the time. You would end up with a 10 per cent tolerance.


Next page . . . . Previous page . . . . Contents . . . . Debates(HTML) . . . . PDF . . . .