Introduction
Groundwater in the Eyre Peninsula exists in two regions, the
main region is at southern tip around Port Lincoln and the other
is along the western side near Elliston. Groundwater in the region
is used extensively for domestic needs including drinking water
as well as for livestock watering. The two regions are prescribed
wells areas to ensure a more sustainable use of the groundwater
resources. >> More
There are several types of aquifers in the region with groundwater
used mostly from the unconfined quaternary aquifer. The EPA monitors
water quality mostly in this aquifer as this is at most risk of
being contaminated by past and present agricultural sources.
The use of groundwater access trenches for stock watering has
occurred historically on the Eyre Peninsula. This activity is
illegal as it provides direct pollution access to the aquifer
through faecal contamination and runoff of other pollutants from
the area. Pollutants include nitrogen, organic matter and pathogens.
Dead stock in the trenches are another potential pollution source.
The main problem with groundwater quality in the Eyre Peninsula
is elevated nitrogen levels.
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 various environmental values. >>
More
Groundwater samples are collected annually from six bores in
the Eyre Peninsula. The indicators that are measured are nutrients
(nitrogen and phosphorus), heavy metals and salinity. The environmental
values that need to be protected are freshwater ecosystems, drinking
water, irrigation use and livestock use.
Water quality classification for 2004
|
Indicator
|
Ecosystem
|
Drinking Water
|
Irrigation
|
Livestock
|
|
|
Poor
|
Good
|
NA
|
NA
|
|
|
Poor
|
NA
|
Good
|
NA
|
|
|
Good
|
NA
|
Good
|
NA
|
|
|
Good
|
Good
|
Good
|
Good
|
| Salinity |
NA
|
Moderate
|
NA
|
Good
|
The groundwater is of poor quality for freshwater ecosystems
due to its high nitrogen (mainly oxidised nitrogen) levels, which
are probably due to inappropriate agricultural practices.
The groundwater is also classified as moderate for drinking water
due to elevated salinity in some areas. This is largely due to
excess irrigation water leaching salts through the soil to the
shallow (quaternary aquifer) system. The salinity was between
494mg/L and 1312 mg/L across the region, while the NH&MRC
guideline (for taste) has a low value of 500mg/L and an upper
value of 1000mg/L. >>
More
The groundwater is good quality for irrigation purposes, since
the nutrient and metal concentrations are not high enough to cause
significant pipe clogging problems.
Overall, the groundwater quality in the Eyre Peninsula is considered
good for livestock in terms of the salinity and metal levels.
However, it should be noted that there is considerable variability
both at a local scale and across the region.
Pesticides in groundwater
Groundwater samples are analysed for a number of pesticides that
may leach into it as a result of past or present agricultural
practices. Pesticides analysed in groundwater samples include
several herbicides, fungicides and insecticides. >>
More
If pesticides are detected in an aquifer, the environmental values
of the aquifer are affected. Therefore, the detection of any pesticide
in groundwater is considered to be a significant problem and warrants
further assessment and or management.
The results of groundwater pesticide monitoring in the Eyre
Peninsula
|
Year
|
2005
|
|
Have pesticides been detected?
|
No
|
Download graphs
Periodic water quality monitoring by the EPA in the Eyre Peninsula
was initiated in 2004. There is currently not enough data available
for graphing purposes.
Download raw water quality data
What is being done to improve groundwater quality in the Eyre
Peninsula
The Eyre Peninsula Natural Resource Management Board has developed
a Water Allocation Plan for the Eyre Peninsula Prescribed Wells
Area. The aim is to ensure the sustainable use of the groundwater
and surface water systems.
SA Water is developing the infrastructure to pump River Murray
water from Whyalla to some regions on the Eyre Peninsula to reduce
the pressure on the groundwater resources. This is due to be commissioned
in 2007.
In a more general sense, the EPA works with the Eyre Peninsula
Natural Resource Management Board, the community and industry
to increase awareness of groundwater quality problems and develop
appropriate management strategies. >>
More
Efforts to improve the condition of South Australia's water resources
are being driven by 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 by these agencies
are based on the protection of environmental values, as explained
in the National
Water Quality Management Strategy.
This page was last modified 23-09-2008
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