Introduction
The Tod River is a brackish to saline stream located on the eastern
side of the Eyre Peninsula which meets the Spencer Gulf just north
of Port Lincoln. The main water quality impacts are likely to
be increased turbidity and nutrients. The Tod River is the only
permanently flowing waterway on the lower Eyre Peninsula and is
one of the main sources of potable water for the region. This
site at White Flat is one of two being monitored on the Tod River
(see Tod River: Koppio) and is located
in the lower section of the catchment, below the Tod River reservoir.
The land surrounding this site is predominantly used for grazing
and cropping. This site has limited riparian vegetation and some
aquatic reed growth in the river. >>
Map (415KB PDF)
Water quality assessment
Water quality is assessed as being in good, moderate or poor
condition by interpreting water chemistry data in the context
of protecting environmental values. >>
More
The ecological health is assessed in spring and autumn. We use
macroinvertebrates for this purpose because they provide a relatively
simple way to assess the health of an aquatic ecosystem. >>
More
Water chemistry is measured each month (or every 3 months in
some locations) because some parameters can cause stress or toxicity
in an ecosystem. >> More
Ecological health
We collect two samples of macroinvertebrates, one from riffle
(or flowing water) habitat and one from edge (still water) habitat.
The diversity of the macroinvertebrate community is used to describe
ecological health as being in good,
moderate or poor
condition.
Go
here to find out how we classify ecological health in streams.
Ecological health assessment for June 2006
| Habitat |
Ecological health
|
| Edge |
Good
|
| Riffle |
Good
|
Both the edge and riffle habitat are usually rated in good condition
at this site downstream from the Tod Reservoir. Small flows almost
always occur in autumn and most spring periods, although the riffle
habitat was absent in spring 2005.
The edge habitat had 26 different types of macroinvertebrates
present. The most common species were nematodes (roundworms),
oligochaete worms and amphipods (Austrochiltonia australis).
The riffle had 24 different macroinvertebrates, the most common
being worms, Austrochiltonia australis, hydrobiid snails
and the predatory caddisfly Cheumatopsyche species.
Waterbugs, beetles and leptocerid caddisflies were absent, and
only 2 damselfly larvae were collected despite the stream having
good aquatic plant cover for a range of odonate species. Similar
patterns were noted from the Tod River at Koppio,
upstream from the Tod Reservoir, during autumn 2006.
Download ecological health data
Water chemistry
The indicators that are measured in the Tod River at White Flat
are nutrients (nitrogen and phosphorus), turbidity and salinity.
The concentrations of these indicators are used to classify the
water chemistry as being in good,
moderate or poor
condition, according to the needs of aquatic ecosystem protection.
Go here
to find out how we organise and classify the chemistry data.
Water chemistry classification for April to September 2006
|
Indicator
|
Classification
|
|
|
Good
|
|
|
Good
|
|
|
Good
|
|
|
Good
|
|
|
Good
|
Nutrient and turbidity levels were low during this period, such
that water quality was classified as good for all indicators.
The total nitrogen and total phosphorus concentrations tend to
be higher during the summer months due to the increase in phytoplankton
growth in the river. This pattern is similar to that occurring
in the Tod River at Koppio although the
summer maxima are generally lower. The minimal shading over the
river tends to encourage algal growth during the summer months.
>> Archived results
Download water chemistry graphs
Download raw chemistry data
What is being done to improve the condition
of South Australian rivers and streams
Efforts to improve the condition of South Australia's rivers
and streams are being driven through various Government agencies,
primarily
The Environment Protection Authority
The Department
of Water, Land and Biodiversity Conservation
Natural
Resource Management Boards
Department
for Environment and Heritage (SA)
Collaborative projects and programs being run in these agencies
are based on the protection of environmental values, as explained
in the National
Water Quality Management Strategy. >>
More
This page was last modified 25-09-2007
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