pesticides and drinking water in Tasmania

Friends of the Earth has launched a brief report on the state of Tasmania’s drinking water, which is available here.

The report is part of a longer term strategy to tie in research from across Australia regarding drinking water issues.

The information was sourced from three Right to Information requests from Southern Water, Ben Lomond Water and Cradle Mountain Water.

The information was only sourced from July 2009 to April 2012.

In terms of breaches to the Australian Drinking Water Guidelines, it would appear that the major concern is relatively high levels of Chlorine Disinfection By-Products from 4 communities in Southern Tasmania, with the largest numbers of breaches associated with the small township of Colebrook. 33 breaches to the Australian Drinking Water Guidelines were recorded at Colebrook. 83.7% of all breaches to the Australian Drinking Water Guidelines occurred due to disinfection by products in Colebrook, Hamilton, Ouse and Wayatinah.

Chlorine Disinfection By-Products occur when organic molecules react with the chlorine used to treat the drinking water. Some DBP’s have been asssociated with cancer. High levels of DBP’s have also been regularly detected in some rural supplies in Victoria and South Australia and Friends of the Earth would consider that the issue is national in its range. Some European communities are moving away from chlorine as a water treatment chemical.

Lead occurred above Guideline levels in 9 instances, with the highest level recorded at Gormanston. Lead is detected quite commonly across Australia with old plumbing fixtures the major problem. Although in a Tasmanian context it would appear that the lead is associated more with local mining history. Cadmium was also detected in the water supply at Avoca. Friends of the Earth is unaware (at this stage) of any other areas in Australia that have a cadmium problem in their drinking water. Again it would appear that local mining history is the source of this pollution.

Also of concern is the E.coli problem, particularly in north eastern Tasmania. Numerous communities are under permanent Boiled Water Notices and this is most unsatisfactory in the 21st Century. The worst offending ecoli problem appears to be at Lilydale in the state’s north east, although detailed ecoli information was not included in information submitted from Southern Water and Cradle Mountain Water.

Pesticide detections appear to be limited mainly to the South Esk River catchment that supplies some areas on the western side of Launceston and the Tamar River. Worryingly in December 2010, 5 different pesticides were detected in the South Esk River. It was also worrying to note that many communities in Tasmania had no pesticide testing carried out in their water supplies until July 2009 when the three existing water authorities started.