By Robert Stewart
No flow in the River Murray that sustains us? Population growth is our total problem — a problem of consumption of resources and the means of producing them that is overwhelming the natural recovery of the Lower Lakes. Left alone the area will recover.
When I was a kid, about 1937 standing with my brother on the high sandhill south point of the Murray mouth, the millions of fish fighting to get out to sea on the fast tidal flow into the lakes was an exciting spectacle. The lakes then were salt water at high tide and flushed out at low, so long as there was a river flow, and of course the 56 flood cleaned the area out fairly well. The old Greek fisherman baiting his long line (with mullet?) waited until the inflow reversed so that he could safely wade out into the stream to cast the baited long line for huge mulloway waiting in the outflow. No flow in the river now? Then flood it with sea water and the oxygenation will fix part of the lakes problem, and time will fix the rest — it always has.
The drought of 1914 reduced the Murray at Waikerie to a series of puddles that one could jump across. My grandfather related stories of the lakes and tide flows across the salt pans drying out to a stage where the salt could be scraped off the surface.
Population interferes with the natural order of things because man wants to experiment, to discover sometime by intent and mostly by accident, and having succeeded wants to sustain. Another 2.8 billion over the next 40 years ( U,N,) will just add to the environmental problems caused by consumption that we know about. That is part of our evolution which got into the fast lane when some fool invented the wheel.
A high tide surge of 1.2 meters in addition to the melting of the polar caps increasing the sea levels cannot be avoided. King Canute found out. What effect that might have is the subject of much deliberation for the low lying Pacific Island nations as it is for the Mayor of Glenelg. Such a level creating a flow into the lakes both at the present mouth and possibly at Maria Creek further south would also contravene the principles of the Ramsar Convention and be a very permanent situation long into the future.
Robert Stewart (Retired)
Engineering & Environmental Risk Surveyor
With permission from the original article