May 2006
The River Torrens has been subject to some recent media attention
regarding the levels of heavy metals in its sediments, such as
The Australian and Channel Nine news on 22 March 2006 and
The Advertiser on 7 April 2006. These media releases portrayed
a relatively negative impression about the condition of the River
Torrens and they were based on a recent article in the journal
Environmental Geology¹. Amongst other things,
the article claimed that the sediments in the Torrens were contaminated
such that in some locations "immediate investigation is
required if ecological damage is to be prevented".
The following points address the issues of metal concentrations,
river ecology and what is being done to improve its condition.
Metal concentrations
A recent EPA study of sediments in waters across the State identified
elevated metal concentrations in the River Torrens. These concentrations
were elevated compared with rural sites (typically double the
concentrations), however results in the River Torrens were consistent
with those collected from other urban waters, including the Patawalonga
River and Dry Creek.
River Ecology
It is likely that the metal pollution in the River Torrens is
having some impact on the ecosystem. However, several EPA studies
indicate that these impacts are not as significant as suggested
by the above article, and are likely to be significantly less
than other impacts associated with catchment urban development.
The EPA recognises the need for continual improvement within the
catchment to further mitigate potential pollution impacts.
Past ecological sampling by the EPA indicates that the impacts
of habitat and vegetation disruption and clearance in the lower
River Torrens is typical of urban rivers and is likely to be causing
a far greater impact than metal pollution. Numerous animal species
have been identified in the lower River Torrens that would not
be present if the metal pollution was having significant impacts.
What is being done?
Numerous initiatives undertaken by government, industry and the
community are targeted at reducing metals and other pollutants.
These include Catchment
Water Management Plans, on-ground works such as pollution
and silt traps, stormwater pollution prevention programs, community
education programs, KESAB
initiatives, industry audits and development of the Environment
Protection (Water Quality) Policy 2003 and supporting
Codes of Practice and guidelines.
¹ Gale RJB, Gale SJ and Winchester
HPM (2006) Inorganic pollution of the sediments of the River Torrens,
South Australia, Environmental Geology DOI: 10.1007/s00254-006-0187-3
This page was last modified 26-02-2008
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