Murray Valley: a recent visit
Last week I was invited to participate in a panel discussion at a meeting of the Murray Basin Association (MBA) in Renmark. The topic was the future of the barrages on Lake Alexandrina near the mouth of the Murray River. For some time I have been reviewing information on the future of the barrages in relation to the interconnectedness of marine sand ingress into the mouth and river flows. The MBA arranged a Q&A type session to flush out various views. It was a great opportunity for me to meet local council and other members of the MBA plus other invited speakers with an interest in the many challenges that face those living and working throughout the Basin.
The visit to Renmark provided me with another opportunity—to traverse the southern Basin by driving from Albury to Renmark and back following the Murray River. My driver was Terry Hillman, another member of the Wentworth Group who is a life member of the MBA. I did note it took an hour longer driving back (uphill?) than driving down the valley, but then we followed the NSW side on the way down, say no more! Terry has remarkable knowledge on all aspects of life past, present and future in the Basin and it was a privilege to go on this journey with him.
As an undergraduate at Sydney University in the late 50s I was exposed to many aspects of the geography and geomorphology of southern regions of the Murray Darling Basin. Professor James Macdonald Holmes had published a book that summarised the work of many of his students. Trevor Langford-Smith and John Rutherford had just completed their doctorates on aspects of settlement history, geomorphology and agricultural economics of the Riverina. Debates over the timing and forces responsible for the giant paleo meanders or prior streams were raging at the time in the now defunct Australian Journal of Science between Langford-Smith and Bruce Butler of CSIRO. I met up with Butler in 1958 while hitch-hiking near Griffith and heard his side of the argument in person. In the 1970s while I was at ANU, results of field studies in the southern Basin by Jim Bowler and archaeologists such as Alan Thorne came to light greatly expanding our knowledge of past processes and occupation of river, lake and dune landscapes. Work on the dunefields and coastal ranges in the western part of the southern Basin from the 1980s onwards also expanded our understanding of the geomorphic/geologic history.
Travelling west down the Murray Valley is a delight to anyone interested in geographic gradients defined by climate and topography. The wet foothills of the Eastern Highlands around Albury stand in marked contrast to the vast, dry flat fluvial surface south of Hay which then transitions into the dunefields of late Pleistocene age. Vegetation reflects both the drying climate, soil type and micro-topographies. The river traverses all these landscapes cutting a gorge through uplifted Tertiary sediments near Renmark. It provides the backbone to the history of settlement since the 1840s first as a means of transport and then from the 1890s the basis for irrigation. Capturing the waters of the river has been a blessing for intensive agriculture but also at the same time creating environmental and social problems. One can only be impressed with the enormous human efforts in clearing Mallee scrub, in digging the water channels, in building river locks, in planting broad acre horticultural and other irrigated crops, while establishing townships to service this “food bowl”. Yet there have been great personal and district hardships along the way, including soldier settler scheme after the First World War, and the insidious impacts of salinization following the clearing of trees.
It was a pleasure to see many neat towns flanking the river with obvious signs of civic pride in gardens and history. However, there are also places that appear to be losing population with deserted shops and even decaying sporting facilities. The Basin is in transition. New industries are emerging such as new almond factories and tourist resorts, while technology is helping drive less on-farm employment. The region will be subjected to forces of climate change, as well as to demands for more food for export. I detect a lack of R&D commitment to meeting future challenges in the different regions of the Basin. Is it now the right time to place more emphasis on the longer term future challenges than to just meeting the pressures of the present? This is something the Wentworth Group of Concerned Scientists will have more to say before the end of the year.
Words by Prof Bruce Thom. Please respect the author’s thoughts and reference appropriately: (c) ACS, 2017, posted 16 October 2017, for correspondence about this blog post please email email@example.com