On 12 June 2009 we hosted the second “Acid Trip” of thirty Adelaideans who were keen to learn more of what is happening around the Lower Lakes and the tributaries (Finniss River and Currency Creek). Like the first trip on 22 March, David Winderlich and his trusty staff took care of the Adelaide end of the arrangements and community members in Milang, Clayton, Finniss and Point Sturt took care of the local logistics.
The bus arrived at Milang around 10.30am where we heard from the school children and their mentors about their work saving the turtles. “It breaks my heart to see these turtles covered in tube worm,” said the eight-year student as she prepared to lever the encrustation off a 30-year-old turtle.
Karyn Bradford, Coordinator of the Milang Old School House Community Centre (MOSHCC) spoke of the enthusiasm of the community to be involved in green projects and the struggle to secure funding that supported community initiatives.
Prof Keith Walker, fresh water ecologist, and Prof Diane Bell, anthropologist, joined the trippers and we took a walk to Lake Alexandrina, talked about the regrowth along the shoreline. The recent rains have refreshed the country. The water levels in the lake have risen from more than a metre to below sea level to minus 0.85 metre at Clayton Bay and minus 0.95m at Milang.
Next we visited the property of Anne Hartnett, Chair of RLCAG, on Point Sturt where acid sulfate soils were first reported in this area. We tested the soil pH according to the CSIRO methodology and found that the soils at the old lake shore line were indeed acid. Our readings ranged through pH 3.5-5.0. However, the pH of the lake remains high at pH 8.72. The most sensible management option then is to keep the ASS covered and undisturbed so that the acid does not enter the lake.
Next stop at the warm and welcoming Clayton Community Hall where Suzy Rex, Peter Bullock and Pat Ingleton had hot homemade soup and local pastries waiting. Carole Richardson spoke to the trippers about her role as Bioremediation Project Officer and work with the Clayton Foreshore Committee; Marian Thompson of her daily observations and dramatic loss of local species in the last 18 months; Keith Walker of the folly of weirs in managing the river; Diane of the planned interventions around the lakes and Suzy Rex of the “sounds of silence” in the once vibrant Dunn’s Lagoon.
After lunch we tracked around to Snug Cove observed the impact of low water levels and recent rains on this wetland and visited the site of proposed weir (regulator) at Clayton Bay.
By 2.30pm we were testing the water running under the Finniss Ford and recorded pH 6.9. Next stop Wally’s Landing, an anabranch of the Finniss River and the location Minister Maywald cited on May 12 as having an acidified stream. We tested the banks (pH 6.4) and in the river, just below the point where the acidic stream joins the anabranch, the pH was 7.2. Several hundred metres further down the river, the lime bank is keeping the water alkaline. The frogs are croaking. The water was flowing and the regrowth at Wally’s Landing is lush.
By 4.30pm the trippers were on their way back to Adelaide and they were asking questions.
Why build regulators when ASS hotspots can be managed locally?
Why can’t we see the most recent EPA monitoring?
Why are local solutions and knowledge not being pursued by the government agencies responsible for looking after the area?
