Legislative Assembly for the ACT: 2002 Week 4 Hansard (10 April) . . Page.. 919..
MS MacDONALD: My question is to the Minister for Urban Services, Mr Wood. There have been several instances of lake pollution this year. Of which instances is the minister aware, what has caused them and what is the department doing to minimise such occurrences?
MR WOOD: Mr Speaker, this is a question I could have faced seven or eight years ago when I was minister for the environment, because the same sorts of problems emerged in those times. This year there have been high levels of faecal coliforms in the lake for some time. A similar problem occurred about the same time last year and has occurred at various other times over the years.
Warnings from the National Capital Authority effectively closed the lake to all recreational and commercial activities for most of the last three weeks. The latest water-quality samples for Lake Burley Griffin have shown an improvement in bacterial levels. The National Capital Authority now advises that West Lake, West Basin and Central Basin are considered safe for boating. Restrictions were lifted yesterday on Tarcoola Reach and Yarramundi Reach. East Basin is the only area still considered to be off limits to boating, but the contamination levels in that part of the lake appear to be declining.
The National Capital Authority says people are still advised against swimming, if they are so inclined at this time of the year, in any sections of the lake. As yet, there has been no confirmation of the cause of the high faecal coliform levels. As pollution of Lake Burley Griffin comes under the responsibility of the NCA, we have been working in coordination with them to address this problem.
The pollution of Lake Burley Griffin is being investigated by a joint working group consisting of the National Capital Authority, Canberra Urban Parks and Places, Environment ACT, Environmental Health, and the Cooperative Research Centre for Freshwater Ecology. A research program to determine the cause of the contamination has been agreed upon by that joint group and will commence shortly.
With respect to the faecal bacteria and other bacteria and health issues, it is the case that current monitoring and subsequent warnings are based on nationally-accepted guidelines. The monitoring is intended to provide an indicator of faecal contamination, but it does not differentiate between faecal sources of bacteria and other sources, such as the decay of vegetation.
The non-faecal sources of bacteria rarely pose a significant health risk. However, as there is uncertainty about the origin of the most recent bacterial outbreak, health authorities are, quite rightly, concerned to ensure that the public is not put at risk. The working group has been working in consultation with the National Health and Medical Research Council and Health and Community Care to develop appropriate health risk assessment and management protocols which it is hoped will reduce the frequency and extent of closures in future years.