Saltwater intrusion in Southern Eyre Peninsula, December 2009

Figure 6. Conductivity slice at -23m AHD showing potential small seawater wedge extending
inland into Uley South. Note: missing data (white strip adjacent to the coast in the
southeastern region) due to wind farm along flight lines (from Fitzpatrick et al. 2009).
The AEM survey also highlighted an area along the southeastern region of Uley
South where the base of the Quaternary limestone aquifer appears to be a
considerable thickness, possibly extending >30m below sea level (Figure 7). These
areas present a higher risk for seawater intrusion, and are in contrast to other areas
where basement is much closer to sea-level (at several points along the coast, the
basement is even understood to be well above sea level, implying no direct
connection to the sea in those locations). The southeastern area identified as highest
risk for seawater intrusion due to the combination of deep basement, thick sediments
and a thin or absent aquitard, is considered the most urgent area for targeted,
ongoing monitoring.
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